The Dust Cap

[bergerud]

Here are pictures of my dust cap dust collection system. The system is fairly simple and very effective, but it is not ideal. The dust cap must be removed during the initial board and bit measurement. The dust cap simply sits on the tray when the machine is measuring. The dust cap is installed only when the machine is carving. The reason that the dust cap cannot remain installed is that it interferes with the bit plate. (Also, there is not enough room for the hose when the carriage moves all the way to the right.)

As you can see in the pictures, the hose is attached to the top with straps and exits through a 1/2 inch hole drilled in the front. (The 1/2 inch hole is the only machine modification.) One has only to connect it to a cheap vacuum. You do not need a 5 hp shop vac. I use a $20 wet and dry vacuum.

The cap is made of a 1 inch piece of 1 3/4 inch Plexiglas tube. This system will work with the CT and the Rock but it will not work with the QC since the ID of the cap is 1 1/2 inch. The plastic flange ring is too wide. It will work, however, if you take it off and just use the metal chuck.

This is a prototype. There should be easier ways to make the cap and bracket. I have a fairly elaborate twist and lock mechanism which takes time to make. I am sure some of you can think of a simpler way.

[gregsolano]

This is really interesting and creative. I hope some solutions are discovered to the bit measurement issue. I am mulling over it myself.

[Fletcher]

What a great piece of engineering bergerud. Kudos! These latest pictures are great to see the level of work you've put in - I love your twist-lock. You've got me rethinking a dust collection design for another machine I have!

As far as the bit plate issue goes, and I'm purely thinking out loud here for the purpose of discussion, could you make your aluminum mounting bracket step upwards so that it clears the top of the touch-off plate instead of just underneath? Then you could shorten the dust skirt enough to fit, and then mount your hose from the other side so it all just clears the top of the plate. You would lose a little bit of suction due to the increased gap between the board and dust-cap but I bet it would still work beautifully.

[Digitalwoodshop]

It's 1 AM and I just had to look at the Forum as I just finished a batch of tags for the night. The Troubleshooting PDF in another post was a Jewel and now I see this setup.... And I am VERY IMPRESSED......

Had some thoughts.....

The Bit Plate.... Since the metal bracket slides UNDER it and does NOT interfere with the bracket that caused me to think.... WHY can't we Move the Bit Plat HIGHER.... Leaving room for a dust cup between the top of the bracket..... and the Underside of the Bit Plate...

The First Step is to find a block of hardwood that is the Thickness of distance between the end of my longest bit.... The 1/8 inch Cutting Bit... and the top of the bit plate. Leaving a little room.... You would want the Bit to travel down and touch the Wood Block taped to the Bit Plate to Prove the Concept..... You are just telling the machine the end of the bit... I have bent my Bit Plate up and down slightly as it does start to sag after a time..... Never saw a Carving Error after moving it.

We need to know if the machine will FAULT out with a Higher Bit Plate Touch SURFACE.....

I won't get to the Shop until about 10 AM in the morning since it's 1 AM now... So if someone wants to try putting something on the bit plate to raise the touch zone and see if the machine Vomits.... IF the machine plays NICE.... Then we can make a Raised Bit Plate..... CUT the old one off and attach a "RON Conversion Kit" and we now have the room for the Dust Cup......

Let the FUN Continue....

AL

[Digitalwoodshop]

Well I laid awake for an hour thinking about it and came to the conclusion that it would "AIR CARVE" if raised..... Was up at 7 AM and now back in the shop about 7 hours later I need to try it.... and see...

I did get a nice PM telling me that my name was mentioned at the Weekend event.... And my Bearing Tightening procedure was popular.....

Gosh fellows.. Now my Ego will be inflated all day....

AL

[Digitalwoodshop]

First Test was a FAILURE..... Added a 3/4 inch block of wood to the top of the Bit Plate but got a Z Stall.... It went down twice then on the 3rd it stalled....

So it "Could" be that the Window at which the Z Current is looked at is smaller than I thought... Will try it with a thinner block of wood next.... See if I can get it to work without a Air Carve..... It did bend the Bit Plate down with considerable force..... so the Window of soft touch must be narrow depending on the bit....

This could happen to someone loading a 1/8 inch Cutting Bit into the machine TOO LONG and the machine would do the same thing.... Z STALL...... So for anyone getting the Z Stall doing the Bit Plate Check, does it hit 3 times before Stalling....?

Back to the Shop....

Second Test with a 1/4 inch block. This time the Z Touched twice and proceeded to the left to touch the board after bobbing down by the brass roller..... I looked like the bit stopped just short of touching the board surface 3 or 4 times... then moved to the center of the Y and asked me to load the bit again...... Selected Enter and it did this a 2nd time.... SO a NO GO......

SO Plan B..... If we could lower the bit flag below the Z Truck Metal Bracket then place a Pin on it consisting of a bolt facing up..... Then cut a slot in the cup to let the whole cup move over the bit flag.....

OR Plan C.... Same setup as shown above but just cut a slot in it to let the bit flag reach inside the cup.... Looking at picture 2, you can see that the slot in the plastic would cut into the right side still leaving a considerable area to collect the dust...

AL

[bergerud]

It does not look too good does it? The bit plate is tough to beat.


If we raise the dust cap above the bit plate, I think the resulting 1/2 inch gap between the cap and the board would be too large. The cap would also have to be 1/2 inch thinner as not to restrict the truck travel.
Lowering the bit plate below the cap with some "pop up" pin might work but then the plate would conflict with a wide board.
Having a slot in the cap for the bit plate seems impossible. The bit plate nearly decapitates the cap and hose.
Raising the bit plate would work but only (according to Al's tests) if the software parameters can be changed.

Even if one could beat the bit plate, there is no room for the hose. Even the smallest most flexible hose gets jammed under the side of the machine when the carriage moves all the way to the right. The hose system would have to change and connect to the front of the cap.

I think there are two separate directions here to think about.


The ongoing question of how to design the ultimate dust collecting system. (What should the Carvewright version D have?)
How to improve the dust cap system so that it is more effective and simple enough for anyone to make and use. For example:




Is there a better, more flexible hose?
Would a circular brush around the cap base help?
Is there a better spring clip type bracket for the cap which would be easier to make and which would let go of the cap in the (user error) case of jamming into the right of the machine?

and so on.

[Digitalwoodshop]

One option is for LHR to add to the next Designer the option for using a Alternate Location for the Bit Plate.... Like the metal guide near the Brass Roller.... And like the selection for Probe Data we have a selection for Bit Plate or Left Side Guide.

Another option is a hinged dust collector that when it gets near the Bit Plate a metal Post hits the dust collector and the spring loaded collector stays toward the center of the machine then when the bit check is done and the head moves away from the bit plate it returns to the normal position.

As for the hose... I did find a Industrial Plastics company that had some Food Grade Thin Plastic Tubing, some with a metal spiral retainer.

AL

[bergerud]

Every time I make something, as soon as I am finished, I think of a better way . Always. Instead of having the hose connect to the side, have it connect to the front with an elbow which is free to rotate. This puts the hose farther forward over the tray ledge (which is good so it can never sag onto the board). As the carriage moves to the right, the elbow rotates and the hose moves to straight up. The hose can be a little shorter and does not restrict the carriage movement to the right at all.
After this is done, we are free to attack the bit plate problem. (I already have one solution. Did you notice the pin sticking out of the truck and the tapped holes in the side of the machine in the second picture?)

[bergerud]

I missed your reply Al as I was replying! Some good ideas you have. Gettig LHR to change anything is, however, a long shot. The problem with having the dust cap move is that it may move when it is not supposed to and that would be disaster. Better , I think, if it can never move. I tried some of that clear hose and it scared me with its collection of static charge.

Imagine a bit plate altered to be 1 inch higher so it swings over the cap. Change the parameter in the software and we are done. Until the software change, we can make the bit plate end where the bit touches a separate spring loaded part which pushes down into the cap and stops at the right depth. A fairly complicated part but it can be made obsolete by the software change.

[mtylerfl]

I missed ...Gettig LHR to change anything is, however, a long shot...

Well, yes and no. They are constantly trying new things, developing new approaches and experimenting/testing all sorts of techniques and designs that would be hard for most folks to even imagine. I've had the privilege to see (and hear about) several of these innovations that are taking place behind the scenes. You would definitely be very impressed with what is going on!

One thing to keep in mind is that even a minor change by a manufacturer often requires that they go through the UL Approval process all over again. This is both time consuming and very expensive. So, when a change is made, you can bet that it has endured the rigors of hundreds (if not thousands) of hours of testing before committing to a particular modification for outside testing, etc.

In a way, you (and us) have an advantage since we can mod our machines all day long without worrying about passing (and paying for) UL testing as well as covering ourselves legally regarding safety/liability of the general public at large. Where we may be at a disadvantage is not knowing what variations and "improvements" have already been tested and eliminated for various reasons - in other words, some things we think may be great ideas may have already been put through the paces long ago, but just didn't work out.

In any case, modding CNC machines of all brands is commonplace and is actually part of the fun for a lot of folks. I certainly enjoy seeing what people come up with. Glad to see that the CarveWright has entered the world of DIY mods and customization.

[gregsolano]

After visiting and touring LHR (I felt like I had free reign and never asked a question that I did not get a full, complete and honest answer), I can say that they really do pay attention to the forum and try to include ideas into future revisions. I felt lucky to talk to the founder and CEO of the company and we talked about the costs and requirements for UL certification. I will not post some of the innovations he told me they were working on, (I even got to see some of them), but I would bet money they are looking at your design and taking in all the discussion on this thread as I am sure they have on all the other Dust Collection threads.

[bergerud]

Thank you both for standing up for LHR. It makes me happy to think things are as you say. Sometimes I wonder if they are foundering and are just trying to survive. I cannot understand some of the things they have done. I would be thrilled if our discussions and ideas on the form somehow help LHR build a better machine. It does not, however, seem that our ideas matter much since LHR rarely participates in the forum. If for example, LHR has tried a similar idea and found fault in it, it would be nice to hear about it.

[gregsolano]

Connie ( http://forum.carvewright.com/image.php?u=5551&dateline=1302294183 (http://forum.carvewright.com/member.php?5551-lynnfrwd) lynnfrwd (http://forum.carvewright.com/member.php?5551-lynnfrwd)) is always participating and there are others I just don't know them by name. The company has to be very careful about letting out innovations or changes as the competition is always watching as well. Not to mention if they throw something out there pre maturely and then UL or some other thing happens that shoots the idea down. Re-tooling for machine changes at the factory level and creating parts that are outsourced are all logistics that have to be taken into consideration not to mention the costs for all the changes during today's tough economic times. The carve tight system, upgraded belts, new bits introduced in the last few months and software updates are all part of the recent upgrades. I know of a few things they are working on right now but I respect their trust and honesty they had with me during my visit to the headquarters.

I know I sound like a company man but I am just a convinced fan.

[Capt Bruce]

I'll second gregsolano's comments having been there last week for the training as a START U member and for the Conference. They were as open with us as family, a word that came up often in the course of the three days near Houston. The founder Chris and all his Staff members could not have been kinder or more gracious hosts nor more open to ideas and fresh thinking. They do pay attention to all our members Carveoholics, Members and Newbies on the Forum and the comments and innovations we discuss, so never feel like a lone voice in the wilderness. And its important to know that our competition also pays attention to what is being said. Never give your competitor an advantage. Dare I quote "Loose lips sink ships." So even telling us what has been tried and or passed by would be giving others free R&D time. Just know that your innovative thinking is highly valued judging by what we saw last week. You've got some great ideas coming to light in this thread so have at it Gentlemen.

On a side note yes your name did come up Ask Bud and the tone was reverant. Our own league of Folk Heros like many others within the CarveWright Family. Keep on challenging our thinking Bergerud. It's that fresh breeze that helps a spark grow into a strong flame.

[bergerud]

If you have been following this dust cap thread, you know that the dust cap had to be removed during the bit measuring procedure before a carve. This was not only because of the bit plate wanting to chop through the cap, but also because of the hose. There is no room on the right of the machine for the hose when the carriage goes all the way to the right if the hose comes out of the cap from the right. We cannot even begin to solve the bit plate problem until the hose is fixed. Here is the hose fix. The hose now comes out from the front of the cap with an elbow on a bearing. The elbow rotates as the carriage moves back and forth. I am quite happy with this as it shortens the hose, it puts the hose over the shelf edge, and it allows the cap intake to be on the side of the cap (makes a vortex in the same sense as the rotating bit). The clearance is very tight. Look closely at pictures 2 and 3 and note how close the elbow is to the case. An 1/8 th of an inch on each side!

For this test, I removed the bit plate. Note in picture 3 how the pin on the truck hits the brass strip and fools the machine into thinking the bit plate has been touched. (I also needed to put in a stop block. Did you know that the carriage continues to the right until it hits the top of the case if the bit plate is out?) With this trick, I did a carve from start to finish with the dust cap installed.

The bit plate problem is next. Any ideas?

[gregsolano]

More ingenious solutions, how are you manufacturing the caps and rotating hose connections etc. so fast and so professional looking? Do you work in a manufacturing plant? Either way you are doing a great job.

[ibewiggin]

How much pressure does the bit actually press on the bit plate? Also how much pressure can the bit plate create? My thinking, make the dust cap the same height as the bit plate, and some how the bit checks on the dust cap, instead of bit plate. Sliding, spring loaded?

[bergerud]

The bit plate swings in just above the aluminum ring. Too low I think. The force is not much; the brass stop I made does not flex much. That is an idea; the dust cap could have its own built in bit plate. Humm...

Thanks for the compliment Greg. You should see my manufacturing plant - a unimat lathe beside my computer and a garage where you cannot see the floor!

[gregsolano]

Once a month I clean down to the garage floor. It lasts a couple of days.

[chebytrk]

Gentlemen, this is really a great thread and has my curiosity going quite a bit. This just might be the Ultimate DC system for the CW if this last bit plate issue can be resolved. It doesn't look expensive to make or purchase and it doesn't appear to make much modification to the machine. I'll be keeping an eye on this thread for sure!

[henry1]

The bit plate swings in just above the aluminum ring. Too low I think. The force is not much; the brass stop I made does not flex much. That is an idea; the dust cap could have its own built in bit plate. Humm...

Thanks for the compliment Greg. You should see my manufacturing plant - a unimat lathe beside my computer and a garage where you cannot see the floor!
Man love the ideal,, keep us updated I love that plan, and what vaccum system you useing for this project

[bergerud]

I am just using a cheap little ($20) wet and dry mini shop vac (picture back in the posts). It labors with the small hose. The dust cap really needs a higher pressure, less volume type vacuum. Something else to worry about later.

[Jeff_Birt]

The dust cap really needs a higher pressure, less volume type vacuum

Good dust collection requires a high volume of air flow, not high suction. This is why you will see recommendations of ~500cfm per machine, and its why dust collection duct-work is so large, to promote airflow. A high suction, low flow device will typically do a decent job with the larger chips, but the fine dust is left floating about. As it turns out the fine dust is the really dangerous stuff. Dust shoes are a common accessory on larger routers, where they have room to run larger hoses, and the shrouding they require around the bit also can serve as a safety device.

In my experience with the CarveWright machine a combination of an a small air blast, directed towards the back of the machine, and a downdraft does a good job with the larger stuff and a really good job with the fine stuff. I'm glad to see folks trying out different ideas though as it seems that some materials, like Azek, may lead themselves to work better with a dust shoe like this than with other methods.

[bergerud]

Those rules of thumb do not apply here where the dust is being removed from a 2 cubic inch volume. I am not trying to suck the dust out of the whole Carvewright machine. That is the point of the dust cap. The dust cap gets all of the fine dust, it is actually a few of the bigger chunks with momentum (low Reynolds number) that manage to escape. My feeble vacuum has a larger a flow rate than is required. It works hard for nothing because of the air drag in the small tubing. I need a smaller vacuum!

[unitedcases]

You know, between this and that shoe thing I think you guys are onto something, maybe you should merge your ideas?

[bergerud]

Very interesting. I tried to get a pipe up the side of the carriage that would not interfere with the machine and gave up. His whole apparatus has to come of and on between carves and it looks like he had to take off the cover. Might be worth it for carving plastic or corain where my little hose may be insufficient.

[unitedcases]

The more and more I think about this the more I think you should just go with what you got. All you have to do is snap the dust cap on after the bit plate check. I get it, you should be able to load the bit and walk away, so to speak. But this is a really great inexpensive idea. I think it is inexpensive? There are great ideas out there right now for dust collection, I think this with a rotating elbow out the front would definitely seal the deal. Just sayin.....

[eelamb]

Bergerud, someone mentioned including the bit touch plate in the cap. If it is spring loaded, when the truck moves to the right side, it can push the bit plate under the bit for touch down. Then when it moves back the bit plate extracts itself. Just a thought! Oh I do like your progress on this.

[bergerud]

I am working on the built in bit plate right now. The spring.

[ibewiggin]

Ok, so when I suggested the idea I was thinking of a flat spring. Like a leaf spring or diving board style. Not a coil. Hope that helps. I have it in my mind but don't know how to describe it, nor the means to manufacture it.

[bergerud]

I have modified the dust cap to include its own bit plate. It works. The original bit plate has been removed. (It is nice not to hear that awful "whack" anymore.) I still have to work on the carriage stop and the bit plate actuator (Roller). The white roller in the pictures is just something from my junk pile. I will make a plate which holds a smaller roller and a carriage stop and which fits onto the old bit plate pin.

Now that the dust cap has a hose out on the end and a new downward force from the bit pushing on the bit plate, it will need the bracket to be stronger. The bit plate should be made of metal or at least be metal where the bit touches. It is not over.

There are more improvements I can think of but here, finally, is the basic prototype.

http://www.youtube.com/watch?v=WGtNg8MTL-o

[ibewiggin]

Yay, I will put in my pre order for two please. Congratulations on the concept, and getting the functionality worked out. A much needed device I must say.

[gregsolano]

I am bowing down in awe, I think the CW techs need to be calling you to work out details for an agreement on making this part of version D ! I also want to purchase one from you as soon as you are ready to start selling. Connie you need to get this to Chris Lovchilc.

[Digitalwoodshop]

WOW.... That is SWEET !!!!!! A Concept I NEVER THOUGHT OF.... WOW.... YOU are one Smart Cookie...... Put me in for 2...

This is a innovation like the ROCK.... Beating the Market.... WOW.....

Is that a BEARING used for the Hose Attachment? THAT is another GREAT IDEA.... I am IMPRESSED...... WOW....

GREAT JOB !!!!!!!

AL

[ibewiggin]

That will make it a lot nicer to do demos at trade shows, and fairs as well.

[unitedcases]

Freakin sweet. Words cannot convey how impressed I am.

[chebytrk]

Yo ! I'm in for one too! As stated, this will be great especially for the START Team when doing Demos at Lowes and other places. Yup, I'm in for one for sure!

[atauer]

Okay,

As a tech, I have seen and heard of a lot of crazy ideas...

That right there is the craziest, most awesome thing I have seen to date! And the fact that it works for you is even better. I can just imagine the look on the repair techs face if that machine ever had to come in for repair.

[Digitalwoodshop]

You got that right..... The Tech would be suprised....

With this Dust Cap I could Save a bunch of money every year in the hours my 220 volt Dust Collector is running..... A smaller 110 volt unit would do the trick..... WOW... The Savings would pay for the cup.... Imagine if we could get it suck through the Cut Motor.... I know my long term plan is to mount 2 machines on heavy wooden shelves on the Wall of the Wood Shop. Above the Machine would be a bracket that contained the Cut Motor facing 90 degrees from where it is now. The Flex would just droop to the Z Truck, no big turn. The Magnet Speed Sensor would be in the motor with extension wires. The Cut Motor could then be free to suck the dust from the cup..... A regular cleaning schedule would need to done to clean the Fan Parts from Stuck on sawdust. I would then vent the Cut Motor outside the shop or to a large container with a Car Air Filter on the top. This is SO COOL....

The metal bracket could be fashioned to make for a secure Alternate Bit Plate... WOW..... Such Progress is such a Short time....

AL

[ktjwilliams]

UR the man Dan !!! Put me in for 2 .... Did U use a bearing for the hose attachment,,, GENIUS !! You should be at NASA designing the next shuttle fleet ...

[bergerud]

You guys are too kind. Thank you for all the positive feed back. It keeps me going into the night. I love to tinker and solve problems. My dust collection problem is pretty well solved. I will now, with what I have learned, make my final dust cap with proper clips and pins. I do not know, however, about anybody else. Who would make and sell these things? I am still waiting to hear if Ron Justice is going the make ER chucks for Carvewright users. He says he will if there is enough demand and I'll bet he would make a sweet dust cap (injection molding is his business) if there is enough demand. Somebody has to step up to the plate. It would be nice if LHR would. I think LHR should offer an "advanced user" spindle in addition to the CT: an ER chuck with a lock button on the truck. They could also now offer an "accessory" dust cap type system. Otherwise, guys, you are on your own.

[DickB]

Very cool!

The clear cap is nice, but I don't see why a similar cap could not be carved using an opaque material on the machine itself.

[Jeff_Birt]

I would be interested to see how these small dust shoes work with a deep relief carving. Some woods can be kind of stringy and I'm wondering if they might get plugged up. The bit touch plate built into the dust cap is an interesting idea, as long as it is the same height as the OEM piece it should work fine. Also don't forget that the shoe will need to come off for scanning (I think.)

[bergerud]

Good point about the scanning. I had thought about that and since forgotten. Its the wire that is the problem. The wire has to be rerouted up, (not totally trivial, some plastic cutting) or the support ring needs a gap for the wire. I will think further on this. Thanks for the reminder.

As for the deep carves, I think a ring brush and a 1/2 inch elbow instead of 3/8 inch would get most of the dust.

DickB: The dust cap is a simple thing; make it out of a plastic pill bottle. Glue the lid with a hole in it onto the support. Forget the elbow and bit plate. Just do like I did on the first try (beginning of this thread). Attach the cap after the bit measurement and before the carve.

[carrothers]

I've been following this thread for some time. I built a down draft system and have attached a large Shopsmith but want an updraft as well. Has anyone thought about putting some type of suction where the "muffler" or dust filter bag or whatever it is called is located. It looks like a one inch hole. Could a suction coming off this hole pull dust out of the top of the machine? I might just give it a try tonight and see if it makes any difference. I was carving some mahogany yesterday and it is the biggest dust generator of any wood that I have used so far. Keep the thread going.

[mtylerfl]

Bergerud,

I'm really enjoying watching and reading about your ideas and innovations. Thanks for including us in your creative process.

[mtylerfl]

I've been following this thread for some time. I built a down draft system and have attached a large Shopsmith but want an updraft as well. Has anyone thought about putting some type of suction where the "muffler" or dust filter bag or whatever it is called is located. It looks like a one inch hole. Could a suction coming off this hole pull dust out of the top of the machine? I might just give it a try tonight and see if it makes any difference. I was carving some mahogany yesterday and it is the biggest dust generator of any wood that I have used so far. Keep the thread going.

Hi Carrothers,

Probably not the best idea to do full dust collection through the muffler port - all the debris would pass through the motor and fan, likely resulting in motor failure and/or clogging. I know some folks do direct the exhaust flow into a closed container - helps cut down on fine dust floating about.

[bergerud]

The motor has two fans. One cools the motor and the other seems to be a lower flow fan the pulls air from in front of the rear roller. (Look under and see the square inlet hole) (Was this part of an original plan to control dust?) I would really like to see the machine take care of its own dust control. I am hoping to convert the front fan into a dust fan. (This should not pull any more dust through the motor.) The problem, I think, is that it needs a different type of impeller and have closer tolerances. It may take some power away from carving, but with the dust cap, we should not need too much power. It will take some experimenting, that is for sure. (In the picture you can see the plastic disc I tried to increase the vacuum by decreasing the input hole radius. Did not seem to do much.)

[Digitalwoodshop]

Interesting idea with the clear disk inside the Cut Motor......

I did cut 6 PVC Signs and I ended up with a big Brillo Pad of plastic at the collector intake.... I ended up baby sitting the carvings and blowing LP Air on the board to break up the chip stuff. It was Labor Intessive as I was not planning to baby sit the cuttings....

The Township will do the finishing and painting for the Township Park.

AL

[Jeff_Birt]

The duct from the fan to the front of the machine is a blower. It blows sawdust off the X tracking roller area. The areas the fans in the cut motor services are meant to be that way, I would not suggest trying to rerout them for anything else.

[bergerud]

That blower gets air from the motor cooling fan not the front fan I am thinking of altering. It does not blow on the x tracking roller as you say Jeff. It has a deflector and blows horizontally toward the truck. It seems to me it can only be to cool the truck.

What is with the other fan which draws air from the front of the rear roller used for? That one makes no sense to me. It causes a slow drift of air through the machine, but, so what? Is it like many other mysterious castings in the machine; a left over from an idea which was abandoned. An idea like dust collection! Does that muffler make any sense? Like the old Craftsman routers, I'll bet they planned to blow the dust out the back into a bag. They could not make it work and so they stuck a muffler in the output pipe. I cannot see any down side to altering the front fan. If it does have a purpose it must be of a trivial nature. I think it will be worth the sacrifice if it can blow out the dust.

This is all wild speculation, it would be cool if someone at LHR who knows could fill in the blanks for us.

[Digitalwoodshop]

I had thought it sucked air from the Electronics underneeth... But never really traced it.... Because LHR must get UL Approval for all functions of the machine, it is possible that early designs were left un used due to the UL... Someone here worked at the UL in 2007 and talked about the UL Process... The 3 wire power cord was a good one.... UL said.... 2 wire.... Just part of the mystery of the machine.... Like the big round hole under the machine... Was that for dust control or a cooling fan.....

A picture from 2007, my first time looking into the Soft Underbelly of the machne.....

AL

[bergerud]

I would love to know the evolutionary history of this most wonderful invention. I guess this stuff is secret.

Thinking about the front fan again, I think my disc will work if it is closer to the fan. Air is leaking back through the gap between the disc and the fan. I need to do some vacuum design research. Tomorrow.

[AskBud]

bergerud,
As I understand the current function of the "Fan Blades", within the motor housing, it has two functions.
I'm not sure how/where it draws the air, but the motor expels the air out the exhaust and via the channel in the top housing, back to the board surface on the keyboard side. It does move (blow) a small amount of dust away from the keyboard side of the board. Perhaps it was designed to blow dirt off the carving bit, as it rises on the keyboard side on each pass.
AskBud

[Jeff_Birt]

That blower gets air from the motor cooling fan not the front fan I am
thinking of altering. It does not blow on the x tracking roller as you say
Jeff.


No, it is not to cool the truck, it creates air movement to keep the tracking roller area clean. I know this from conversations with CarveWright engineers when I was looking for a built in source of air for my air blast. They strongly advised against trying to redirect any of the built in fans/ducts. I'm just trying to pass along the information I learned from them, FWIW.

EDIT: As I was driving to work it occurred to me that the original beta machines had an optical bit sensor instead of the bit plate. There was a duct that went back direction to keep the sensor clear. I think the cut-motor was redesigned for the current generation of machines, I know the design has been beefed up in the past couple of years to prevent the nose where the flex shaft hooks up form breaking off. (I think Al was the first one with mega-hours on a machine that had that happen.)

I was doing some research yesterday into how commercial circuit board routers maintain the correct height over the PCB laminate and found a few good photos of the dust shoe they use. Keep in mind that there is very little material removed from the PCB and it still looks like they are using a 1" dia hose to get the required air flow. I like the idea of a dust shoe on the CW but I'm still bothered by the idea that a small hose will tend to plug up and/or not have enough airflow. (I hope it works great though.)



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[bergerud]

What you are saying is that the design purpose of the blower is to cause a circulation in the machine which keeps the dust moving toward the right so that dust does not settle on the tracking roller area. Maybe that is right.

The more important question for me is purpose of the other fan.

[bergerud]

My final addition to this Dust Cap prototype is a brush. It makes a noticeable difference. Larger chips which flew out horizontally between the cap and the board now are stopped by the brush. The first picture shows how much escaped during a 45 minute carve. The second shows the brush. See the youtube video of the prototype with brush in action.

http://www.youtube.com/watch?v=Dxyr3iGIiKY

[b.sumner47]

WOW !! You outdid yourself, nice job on the brush. Please let me know if I can get 1 or 2or 3. Thanks, Capt Barry

[bergerud]

I am finished with the Dust Cap 1.0 prototype. It really does to work quite well. Unfortunately, I do not think it will solve the dust collection problem for the large number of Carvewright users who need dust collection. Like the ER spindles, I doubt the idea will be widely used unless somebody makes and sells them. I think these are a little too hard for most people to make themselves and I doubt that anyone (let alone LHR) is going make and sell them. It is just not simple enough. Ideally, a simple dust collection system should be manufactured by LHR and offered as an upgrade option for old machines and included as an integral part of new machines. I do not think the Dust Cap 1.0 is elegant or simple enough to fit this bill.

I do, however, have another idea which might fit the bill. I do not know how long it will take me to experiment and test the idea, so, I thought I would explain it and see what you guys think. I have also made a quick sketch of the idea below. (I know, it looks like a toilet!)

The cut motor has a second, front fan which intakes air from a hole above the rear roller and expels the air out through the muffler. (You can see the hole if you look up underneath. This fan system is independent of the motor cooling fan which has a different input and output.) It should be possible to use this second fan system to power a dust cap. There is a space between the back roller and the lower carriage bearings of a little more than ½ an inch. There is room in this space for a ½” by ¾” by 17” rectangular air manifold. This manifold could be mated to the fan intake on top and could have a slot all along the bottom which the dust cap output could bend up into. The slot could be sealed either by rubber flaps or by brush seals so that air could enter only where the dust cap output separates and penetrates the seals. The dust cap output would be free to slide in the slot connected to the low manifold pressure as the carriage moves back and forth. The bracket which holds the dust cap would have to be thick and hollow to connect the air flow under the carriage to the manifold. There is not much room and the board sensor would need a hole to see though. The bracket and cap can be of low enough profile that it can slide under the (possibly modified) bit plate.

The second fan system did not have enough vacuum to power my Dust Cap though the long small hose. I am hoping that with this direct connection, it will have enough vacuum. If it does not, then an external vacuum could be connected to the muffler port. (Even if it does have enough vacuum, this trick might be good when carving denser plastics. I believe, however, that the fan can be modified to increase its vacuum if it is not enough.)

Take a minute to think about such a system. The machine would keep itself clean with its own power. The vacuum would always turn on when and only when it is needed. There would be no hoses in the machine and no interference to front access. The dust would go out the back into a filter bag or a dust system. I cannot imagine that there is a cleaner solution than this.

I am pretty sure I can make this work. I do not know if LHR has tried this idea or if they have even experimented with dust collection at all lately. If they are interested in dust collection, they would have to be interested in this. If not, I think a third party might step up to the plate and offer this system as a simple bolt in.

[ktjwilliams]

Dan,,,, Do U get any carving done with that supercharged machine of yours ??? My brain hurts from watchin U think .... LOL... Luv UR ideas and designs though... Now because of U,, while my machine is working I sit there sometimes just watching and pondering possible improvements... I've thought of a few, but have yet to put one together. The other day I took my hole machine apart just to see what's what and where I can sneak or weave stuff through... Glad to report the machine is working fine after being put back together... While I had it all apart, every piece got a good cleaning....

[bergerud]

Lately, I only carve to test the machine. If I could just stop thinking of new ways to alter the machine, I could get back to normal life!

[bergerud]

While exploring the space between the carriage and the rear roller (where the manifold is going), I noticed something very interesting. There are places to drill bolt holes already in the casting right where I naturally want to put the bolts to hold the manifold! Now I think I know the meaning of the second fan system. Early in the development of the Carvewright machine, the designers tried or planned to have built in dust collection. The space probably had a manifold bolted in with a long slot in it to pick up dust just like the front loading dust collectors which others have made. My guess is that second fan was simply not powerful enough for such a slot and the idea was abandoned (or postponed). They stuck the muffler on it and gave up.

I would have to say that the second fan system and the muffler attached to it as is has no use whatsoever on the Carvewright machine. It is there as either left over from a failed dust collection design or it is there there to be used in future designs. (I expect a "no comment" from LHR on this one!)

I am finally finished planning and am ready to make the parts for the Dust Cap 2.0. The trick turns out to be in the design of, what I call, the "sliding port manifold". I think I have a neat solution. (the seal idea in the sketch below had too much friction and leaked.) Anyway, I am so confident that my Dust Cap 2.0 idea is going to work that I have started to think about the problem of how to beef up the second fan system. I have already tried some alterations to the input of the fan without success. Now I think the problem is the output. Think about this: the air in a centrifugal fan spins fast in circles and is slowly "thrown out" from the center. The direction of the velocity is mostly tangential and so, in the design of pumps and vacuums, the output is also tangential. On the Carvewright second fan system, the output (to the muffler) is perpendicular! The air cannot get out unless it changes direction by 90 degrees. Do you think this could be the reason that this 20,000 rpm fan has no suck?

[bergerud]

I finally made all the parts to test my dust shoe idea. Sad to say, it did not work very well. (The dust cap leaves it in the dust!) I do think, however, that it is a good idea for many reasons and that it should be made to work.

For the system to work, there must be a large air flow through the constricted passage in the shoe. A good vacuum in the manifold is essential. With the smallest leak in the system, the vacuum is lost and the flow through the shoe drastically drops. My system had leaks. The worst leak was between the manifold and the shoe. With the manifold bolted to the casing and the shoe bolted to the carriage, the critical clearance between them was impossible to control. My parts were just not precise enough. The only way this idea can work is if one can make the “sliding port” manifold totally air tight.

I can see how every one of my parts should be made differently, and so, it’s back to the drawing board. I have other commitments however and so, for now, I have to quit. Someday, I will get back to it because I believe that such a system should be a part of the Carvewright machine. I can only hope that my attempt gives LHR the same belief.

I would like to thank Camosun College for supporting my “research” into dust collection. (This time spent is called “professional development”. I usually spend part of this time carving mathematical models and demonstrations for students.)

[bergerud]

Here are some more pictures of the dust shoe system parts.

[gregsolano]

Your engineering skills amaze me. LHR needs to contract with you to solve this problem once and for all.

[bergerud]

I have to say that the Dust Cap idea really works well. You hardly ever see a speck of dust. I find it such a joy to use.

The "top loader" dust collectors some are making using may be fine for the carvers with "real" wood shops and serious DC systems. The carvewright, however, is a hobby machine and I suspect most carvers do not have or will ever have a 4 inch hose, 5 hp, DC system. The Dust Cap on the other hand works with a disposable mini shop vac.

Do you guys think that many users would carve a dust cap system for themselves if I create all of the files and the procedure? Except for the bearing, hose, spring, and some sort of brush, I think it can all be carved. The parts could be made of cast acrylic (or hardwood I guess). The main parts are the cap, the curved tube, the bit plate, the base plate, and the stop plate. I stayed up late last night seeing what I could do in designer. See below. I think it can be done!

This would be a fairly advanced carving project. The challenge, of course, is to make it all as simple as possible. I would need help from some of you guys as beta testers to test the QC, Rock, and CT and to figure out where the get or make the parts we cannot carve.

I need some honest opinions here. I spent a lot of time on the ER spindle idea thinking that people were going to make them, have them made, or buy them. Only Kevin, who I sent a spindle, realized how good they are and made one himself. I do not want to go to all the trouble with the Dust Cap if it is going to be the same story.

If some of you serious members are onboard with this idea, we can start a new thread and see if we can get the carvewright to mill its own Dust Cap.

[unitedcases]

I would give it a go. I use a mini shop vac. I am just not very good with creating the pieces on my own. I think if you spell it out you will get more responses.

[RogerB]

Nice I like Your Idea. Have sent a pm can you cut aluminum with the cw or the other parts.

RogerB

[b.sumner47]

I'm not a machinist, but would be real glad to get involved in this project. Capt Barry

[Digitalwoodshop]

Nice I like Your Idea. Have sent a pm can you cut aluminum with the cw or the other parts.

RogerB

Aluminum NO.... Parts from Cast Acrylic Yes.... Extruded Acrylic melts to bit and snaps bit. Feed Rate too fast for Aluminum and all the electrical exposed parts.... ZAP !!!!

AL

[bergerud]

I plan to make all of the parts with cast acrylic. (Wood to experiment of course.) The question here is: do you think many users would carve this project if I go to the trouble to iron out all of the bugs? They would have to buy cast acrylic of various thicknesses, some bearings, some hose, and so on. I would call this an advanced project. This would be using the carvewright as more of a miller than a carving machine. I like a challenge but not if no one benefits from it.

[CarverJerry]

I know I'd give it a try. I've been watching you develope this and really like what you have come up with.

CarverJerry

[Gary Koval]

I second what Jerry said. Hmmm, I have a downdraft table and plenty if 1/2" corian to use as the material, course the glue for the corian is astronomical, just a thought.

[gregsolano]

I would be very interested as well

[DickB]

You might also consider buying acrylic, bearings, and hose in bulk and selling packaged kits for us to make our own. I know it can be expensive to buy small quantities like just one bearing or a couple feet of hose. You could make a little money and we'd still save money.

[bergerud]

If I lived in the States, that would be a good idea but I live in Canada. If we get this off the ground maybe someone down there could buy bulk stuff and redistribute.

[eelamb]

Thought I would give this a shot in modeling. And this is what I came up with. I have sliced it and it looks good. But need to slice it a different way and of course it would be made of wood. You would have to make the alum bottom, and come up with a bit plate for it too, such as bergerud made. Will try to slice it better later on and post the MPC. There would be a top and bottom for each section. Thus 4 PTN's all cut from a .75 inch thick board. (two sided carve). Once carved top and bottom would be glued together.

Note: or a top and bottom section glued, and you drill the side hole.

[eelamb]

Decided to post the top and bottom section, where you would drill the side hole.

[eelamb]

I see I did not explain what I had in mind for the pattern.
1) top and bottom of large circle can be sanded down to size desired.
2) side arm can be cut to length

The side section is centered on the outside of larger circle. Overall size is 2" outer wall, 1.5" inner hole, with side section of 1.25" dia. Complete length with side section is 3" with the height of 1.5"

Another thought is the tubing pressed to the bearing, anddrilling a hole for the bearing in the side section. I believe this is what the original had.

Bergerun is this about the right size, and will this work with what you had in mind?

[bergerud]

The clearances are very small. The dust cap I made barely fits in almost all dimensions. The outer diameter is 1.75, the inner is 1.5, the height above the bracket is 1.0, and the diameter of the pipe nipple is 1.0. The pipe nipple cannot be very long or it hits at each end of carriage travel. There is room for a bearing and that's about it. I used 3/8 tubing which I bent as much as I could. It would be better to use a 1/2 formed elbow of some kind. I worry about the friction in the pipe connection you are thinking of. There is little room for bushing length so it may bind. I like the bearing.
I want to have the machine carve all of the parts as completely as possible so that anybody can make it. The hole for the bearing, the slot for the bit plate, and so on.

[eelamb]

In that case with the clearance, making it from wood is out. It would have to be cut in cast acrylic. With the wall thickness of .125 on the larger circle, wood will crack.
Ok help me out here on dimensions:
height = 1"
outside = 1.75"
inside hole = 1.5"
bearing dia = ?
thickness of bearing = ?
suction hole size= ?
length of side suction from edge = ?

I can duplicate the model to the size you give me. It would take 4 patterns to make the suction side hole/bearing hole. Will take a little thought on slicing to get 2 sided carve but I believe it can be done. Thus if a pattern is created, the end user could carve it, and buy the necessary parts.

Is it possible to place the bit plate on the bottom bracket. that way a slot can be cut on the outer circle to fit over the bit plate?

Other thought is the caring bit is tapered!

PM me if you want, maybe we can come up with something for the group.

[bergerud]

Here are some of the mpc files I started on. It would be a four sided carve using carving and cutting bits. The block needs to be held in a jig.

I have found RC bearings that are 1/2 X 3/4 X 5/32 which would allow for a 1/2 inch out pipe. The bit plate has to be in the middle of the cap to match the height of the stock bit plate. I was thinking of making the base plate also from cast acrylic but I want a break in it (like the dust shoe bracket) so that one can use the scanning probe with out having to remove the base plate.

Were you thinking about making the cap in layers?

[eelamb]

Of all the nights the dsl is acting up.
Yes 2 sections glued together. This will allow the inside to be cut to size. The slot can also be cut in the wall in the middle too (both sections) here is an image of some of my thoughts.
The side hole would be larger at the end to allow for the bearing.

[eelamb]

The carve would be two double sided carvings, top section and bottom section, and when the board is flipped, it will be the inside sections of he top and bottom. I need to work on the slicing of the model to obtain this, but I believe it is possible.
With the two sections a slot can be cut into both section (in the middle) with half the slot on both the top and bottom. Or on either one if necessary, to offset the slot. Doing this will eliminate the 4 sided carve and special holders.

This can all be done in wood for testing, but I feel the side walls will not be strong enough in wood, but once finished it may be worth a shot if a wood like iron word is used or another dense hard wood.

I will look at your MPC for further information I need and see if I can come up with something tomorrow.

[ktjwilliams]

Aight Dan.... U and Eddie seem to be moving along on this so I won't add to the process... I have faith that U guyzzzz will get it together... Anyway Dan How ya been,,, Eddie good to meet ya...

Kevin...

[bergerud]

The two halves seems like a good idea. I like it. I was thinking of making up the thickness from 1/4 inch layers instead of one thick piece. Carving and gluing and carving, but, your idea is better. It would be nice to make the cap out of 1/4 inch sheet. Glue layers together and then carve as you suggest.

You know, I put the mpc out there to show it was possible and to see if there was enough interest in this to inspire me to commit the the project. Now you have me hooked.

I was doing two halves for the pipe. See the mpc.