Pattern Jumps Track

[Steven Alford]

This has me stumped but I am sure it is simple.
There are three pictures attached that show my problem. The first picture shows the pattern I was carving and how it "jumped" by 1/8" after about 10% into the carving. This happened maybe three months ago. It never did it again. After about 50 carves or so of the same pattern it did it again last night (second pic) in EXACTLY the same spot. I am positive the wood did not move, nor did the sled move. It is as if the truck jumped track while carving. It was late so I opted to try again this morning. I cleaned the machine good (with air), especially the gears and the belt that moves the truck back and forth. But it did it again, in the exact same spot (third picture). What is going on??

[cnsranch]

Too much of a coincidence to make it coincidental :mrgreen:

That is a weird one - there's no way you have a bad tooth, or a chip stuck when it's skipping in the same place.

Can't be a power spike............

It's got to be in the mpc - is it a big deal to redesign the mpc, re-save it, and try again?

Maybe if you post the mpc, something will show for one of us that doesn't show on your computer.

[Steven Alford]

Here is the MPC, but I doubt that is the problem because I have been using this same MPC all along, for over three months with no changes.
I wonder if something could be wrong with the file that is on the memory card ?

[Steven Alford]

Too much of a coincidence to make it coincidental :mrgreen:

That is a weird one - there's no way you have a bad tooth, or a chip stuck when it's skipping in the same place.

Can't be a power spike............

It's got to be in the mpc - is it a big deal to redesign the mpc, re-save it, and try again?

Maybe if you post the mpc, something will show for one of us that doesn't show on your computer.


Power surge........
That has me thinking. Two days ago we had one hell of a thunderstorm. I was carving away when a big lightening and thunder hit. The lights in the shop went out briefly and the CW slowed down on it's carve but did not quit, it kept on carving, weird!! I thought a power surge like that would shut the machine down. Maybe it did something to the file. I will re-load the file onto the memory card and try to carve again and see if that is the problem.
Of courese, that does not explain why it did this three months ago and never again until yesterday.

[cnsranch]

Gimmie me a minute - it seems to be jumping right where you have the patterns merged...

[mtylerfl]

Here is the MPC, but I doubt that is the problem because I have been using this same MPC all along, for over three months with no changes.
I wonder if something could be wrong with the file that is on the memory card ?

Hello Steven,

I think if you delete the two overlapping pattern outlines (the area where the "skip" occurs), that will eliminate the problem. (MODIFIED mpc attached)

Please let us know if that took care of it for you.

P.S. - if that doesn't work, try making a group of the two patterns (one group for each side...or group all four patterns). Ahh - what the heck - I made one with the patterns grouped for ya. (attached)

[cnsranch]

That's it!!

I'm telling you, MT, you gotta sign up for Millionaire:mrgreen::mrgreen:

[mtylerfl]

That's it!!

I'm telling you, MT, you gotta sign up for Millionaire:mrgreen::mrgreen:

Well...let's see if it actually solved the problem first!;)

[Steven Alford]

How do you delete the overlap??

[cnsranch]

Just highlight the four paths that do not have cutpaths associated with them, right click and delete them.

(Beat you, MT)

[Steven Alford]

Sorry guys, that did not cure the problem. It jumps in exactly the same spot.
And again, keep in mind, this has carved perfectly for the last 50 times or more.

[Steven Alford]

Just highlight the four paths that do not have cutpaths associated with them, right click and delete them.

(Beat you, MT)

OK, I see, you just delete the entire outline, not just the overlap. So in other words, if you have an outline that was used in the pattern making for whatever reason, you should delete it when you are finished, don't leave it in or it will confuse the machine. Right?

[mtylerfl]

(Beat you, MT)

Dang - was in the bathroom.;)

[mtylerfl]

OK, I see, you just delete the entire outline, not just the overlap. So in other words, if you have an outline that was used in the pattern making for whatever reason, you should delete it when you are finished, don't leave it in or it will confuse the machine. Right?

Well, that's the theory. Hope it works. Did you see my other suggestion about grouping the patterns? That was my other guess to try, if deleting the outline overlaps didn't do the trick.

[Steven Alford]

Yes Michael, I saw it, in fact that is the file that I used. Any suggestions??

[eromran]

Not really sure if this is any thing like you are tring but what about get ride of all cut paths and just use peirce would that give you same look ? You would then only be using one bit also.

[cnsranch]

Dang - was in the bathroom.;)

What the hell were you doing in the bathroom for 25 minutes this time of day?

[Steven Alford]

Ed,
What I have is pierce. And it only uses one bit, the 1//16 carving bit.
Your mpc file has no pierces like mine so it does not work for what I need.
Basically, the file was fine until yesterday and something has gone wrong that it won't carve.

[cnsranch]

So in other words, if you have an outline that was used in the pattern making for whatever reason, you should delete it when you are finished, don't leave it in or it will confuse the machine. Right?

Yeah, if you "outline" a pattern in order to create a cut path, once the cutpath is created, you don't need the outline any more.

[Steven Alford]

So if my mpc is ok, then why is it jumping? Is there something wrong with the machine??

[eromran]

Ed,
What I have is pierce. And it only uses one bit, the 1//16 carving bit.
Your mpc file has no pierces like mine so it does not work for what I need.
Basically, the file was fine until yesterday and something has gone wrong that it won't carve.On your original MPC file you posted its not showing peirce checked

[cnsranch]

Steven

Carve the attached - I'll bet you a beer the jumping won't occur (it's your original mpc without the paths that aren't needed).

That's the only thing that could be causing the problem - it shouldn't, that's why it only does it occasionally. I don't know why it does it, but I'm betting that with the paths gone, so goes the jump.

[Steven Alford]

For which part?
All of the "holes" that go through the wood are pierces. The cut out at the bottom of the wood is also a pierce, after I hand drew the outline, made it a carve region and assigned a pierce.

[mtylerfl]

For which part?
All of the "holes" that go through the wood are pierces. The cut out at the bottom of the wood is also a pierce, after I hand drew the outline, made it a carve region and assigned a pierce.

Hello Steven,

The Pierced Regions are fine. No problem there that I can see.

So, if I understand this correctly, you already tried carving the GROUPED_MODIFIEDFrontBack8.mpc and it still skipped in that area - correct?

[Steven Alford]

What kind of beer do you drink???

That one carved fine. Was this file any different from the one Michael gave me where the outline was removed and the four patterns were grouped??

[Steven Alford]

Hello Steven,

The Pierced Regions are fine. No problem there that I can see.

So, if I understand this correctly, you already tried carving the GROUPED_MODIFIEDFrontBack8.mpc and it still skipped in that area - correct?

That is correct Michael. But cnsranch just sent me a file that just had the outline removed and it carved fine. What's the difference from you file, other than the grouping??

[cnsranch]

What kind of beer do you drink???

Really expensive stuff:mrgreen:

That one carved fine. Was this file any different from the one Michael gave me where the outline was removed and the four patterns were grouped??

Not sure.........

[mtylerfl]

That is correct Michael. But cnsranch just sent me a file that just had the outline removed and it carved fine. What's the difference from you file, other than the grouping??

That is strange - there is no difference that I can see at all!

(I used Designer version 1.152 Build 7739)

The last thing I was going to suggest (before you said that the one file did work) was to assign a Merge Style: Additive to the group of patterns - NOT each individual pattern, but the Group itself via the Carving List.

Oh well, it's a mystery!

[Steven Alford]

Thanks guys. I don't know what most of us would do without the good info we get on this forum. I would have spent days trying to figure that one out. And like I said on the first post, it was simple!!

[cnsranch]

Thanks guys. I don't know what most of us would do without the good info we get on this forum. I would have spent days trying to figure that one out. And like I said on the first post, it was simple!!

Same build here, MT

You're welcome, Steven.

Now, pay it forward - go help dvel56 - I can't get his center hole figured out the way he wants it (slow day at the office:mrgreen:)

[mtylerfl]

Same build here, MT
)


Thanks for letting me know.

Still strange though - the first mpc (MODIFIEDFrontBack8.mpc) I posted looks identical to yours, but Steven tried the second file - i.e., the one that had the patterns in a group.

Still, I don't know why that second one didn't work - seems like it should have anyway. I suppose if Steven carves the first one, it would work the same as the mpc you did up for him.

Glad something worked! - got Steven back in the saddle at least!

[cnsranch]

Still, I don't know why that second one didn't work

Mine may have been the lucky one - it may crash on him sometime in the future like the one he has been using.

His shouldn't have crashed anyway - why it did, I have no idea - the outline was the only common thread that could have cause some kind of problem.

[Steven Alford]

Mine may have been the lucky one - it may crash on him sometime in the future like the one he has been using.

His shouldn't have crashed anyway - why it did, I have no idea - the outline was the only common thread that could have cause some kind of problem.

That is my fear Jerry, even though it is working now, it may crash and do the same error in the future. I sure hope it does not. I agree with your thinking; with the outline gone, there should be no problem.

[Digitalwoodshop]

I just jumped into this one and was disappointed when I saw the fix was a Pattern Problem.... Then was happy (sorry) to hear it was still not solved...

I think it is a dull bit AND the screw on top of the right side Y pulley is loose letting the Y Belt skip a tooth or 2 when the going gets tuff.

Try a new bit first. Oak is hard and I believe that is the problem.

AL:rolleyes:

[Steven Alford]

Al, you may be right because it is not fixed, it is still doing it. My bit has about 65 to 70 hours on it so it should be about time for a change.

The first pic shows the jump (two of them!) and next pic shows what it should look like and the third is a close up of the problem.

[Steven Alford]

I just jumped into this one and was disappointed when I saw the fix was a Pattern Problem.... Then was happy (sorry) to hear it was still not solved...

I think it is a dull bit AND the screw on top of the right side Y pulley is loose letting the Y Belt skip a tooth or 2 when the going gets tuff.

Try a new bit first. Oak is hard and I believe that is the problem.

AL:rolleyes:


Al, where is this screw exactly??

[AskBud]

I think this is a prime example as to why we need an option to select the "Hardness" of the material being carved.

Most woodworkers and metalworkers know that you need to adjust your cut feed rate to match the "hardness" of the material at hand. Sometimes we even adjust the "Depth of Cut Per Pass", however, we do not have either option on the raster carve at this time.

We have all seen where the Depth per Pass has eliminated bit breakage on the Cut-Path. We need the same option on the Raster carve.
AskBud

[PCW]

Al, where is this screw exactly??

Steven,

If you follow the Y belt to the end (opposite side of the keyboard). There is a phillip's head screw on top of the idler just loosen stretch the belt then tighten.

I would check the belt for tension with your fingers before adjusting.

[Steven Alford]

Steven,

If you follow the Y belt to the end (opposite side of the keyboard). There is a phillip's head screw on top of the idler just loosen stretch the belt then tighten.

I would check the belt for tension with your fingers before adjusting.

Ahh, said the blind man! The Y-Belt Tensioner Assembly, Part #49 of Parts List Page 12.

If this thing was slipping a tooth on the gear every now and then, can this damage the gear?

[PCW]

Steven,

Not to say it can't happen but more than likely the belt could slip a tooth and screw with the tracking.

[Steven Alford]

I just bought these new bits from Precise Bit and they are supposed to last 2 to 3 times longer than the original CW bit. NOT!! They only lasted about 5 hours longer (50 for CW, 55 for Precise). I guess I will try Ron's bits next time, maybe, if I am lucky, they will be as good as his Rock!!

[PCW]

Also Jeff sells the PreciseBits 1/16 in. Zrn Coated. Have not tried them yet but plan on doing so ($39.95). Link (http://soigeneris.com/PreciseBitsCarving.aspx)

From Jeff's site>

ZrN is shorthand for zirconium nitride. It is a hard chemical coating applied to cutting bits to improve their performance and greatly increase their lifespan. It has proven itself to be a strong surface enhancement coating that is suitable for machining aluminum alloys, high silica aluminum, cast iron, non-ferrous materials, high temperature alloys, stainless steel, glass-filled plastics and wood. It is not recommended for machining carbon steels.

The benefits of the coating will vary somewhat depending on the material being cut. For instance the life of a ZrN coated tool cutting ebony will be increased about 300%; the effect of the coating on the tools cutting edge when cutting in wood causes the bit to cut like a slightly worn bit, but it will maintain this same performance 3 times longer than a non-coated bit. Cutting copper, gold or silver with a ZrN coated bit shows an immediate increase in cut quality with beautiful edges for the 200% greater lifespan of the tool.

[Digitalwoodshop]

The bracket that holds the right Y Pulley has a screw and spring on the side to pull the slack on the belt. The screw on top holds the cover to the cut motor wires and when snug prevents the spring from compressing and letting the Y skip a few teeth causing the offset. Too Tight and you might see a clean Y Rails or Y Stall if the bit is dull. The dull bit might work just fine in pine like I use 99% of the time. But when you are cutting OAK the bit needs to work a little harder and the bit might end up lagging behind the Y motor position.

This is where a "BOARD DENSITY SELECTOR" needs to be added to the DESIGNER SOFTWARE to SLIGHTLY ADJUST THE FEED RATE based on:

Balsa Wood
Pine Wood
Popular Wood
Maple Wood
Oak Wood
IRON Wood
:lol:ACRYLIC:lol:

All with slightly different feed rates. Using the IRON wood setting would let us cut Acrylic at a safer speed then the ONE FEED RATE for EVERYTHING set to PINE..... Make it more User Defined than, you can have any feed rate you want as long as it is the PINE feed rate.....

I think we are at the same point as we were with "DEPTH OF CUT" Cutpath when I and MANY others pitched the idea to LHR.

Just my 2 Cents on the Y

AL

[mtylerfl]

Interesting idea about the wood density being the source of the problem that Steven is having. I did not think of that. It seems to make sense, since Steven said he had carved that pattern more than 50 times before he started having the "skipping" issue.

Could be as the bit became less sharp that the resistance became greater. I'm very curious to see if the bit or the belt adjustment is at fault.

What makes it harder to diagnose is that the problem is somewhat intermittent - at times it carves fine - at other times it skips. I guess if he carves 50 more without a "skip" with a new (sharp) bit and if the belt/gear is verified as ok, then we can assume it didn't have anything to do with the pattern outline overlap at all!

Al, you probably have more carve time than anyone else on the planet I think, so your diagnosis is likely the most informed and accurate.

[PCW]

I just wounder how this would be incorporated. Would it just slow down the travel of the axles or make multiple passes. Maybe that is why they have the optimum setting for. This could be used to take less of a bite on hard surfaces.

It could be a problem with balancing carving time and carving problems. I would hate for a 6 hour carve to turn into 9 plus hours. It has to be hard on the engineers to come up with a sweet spot.

When the machining process is so automated for the ease of use we give up the control of the process in which it is done.

G-code is a alternative but the complexity of learning the programing will turn off the people that are attracted to the simplicity that the CW machine offers.

Tough call

[Steven Alford]

Also Jeff sells the PreciseBits 1/16 in. Zrn Coated. Have not tried them yet but plan on doing so ($39.95). Link (http://soigeneris.com/PreciseBitsCarving.aspx)

From Jeff's site>

ZrN is shorthand for zirconium nitride. It is a hard chemical coating applied to cutting bits to improve their performance and greatly increase their lifespan. It has proven itself to be a strong surface enhancement coating that is suitable for machining aluminum alloys, high silica aluminum, cast iron, non-ferrous materials, high temperature alloys, stainless steel, glass-filled plastics and wood. It is not recommended for machining carbon steels.

The benefits of the coating will vary somewhat depending on the material being cut. For instance the life of a ZrN coated tool cutting ebony will be increased about 300%; the effect of the coating on the tools cutting edge when cutting in wood causes the bit to cut like a slightly worn bit, but it will maintain this same performance 3 times longer than a non-coated bit. Cutting copper, gold or silver with a ZrN coated bit shows an immediate increase in cut quality with beautiful edges for the 200% greater lifespan of the tool.


These ARE the bits I am referring to. They do not last as long as advertised. They are excellent bits, but they will not last any longer than the original CW bit.

[PCW]

These ARE the bits I am referring to. They do not last as long as advertised. They are excellent bits, but they will not last any longer than the original CW bit.

Dam Steven what kind of wood are you cutting.:D
Those are made to cut cast iron.:confused:

[Steven Alford]

Well, I changed the bit this afternoon and checked the Y-Belt and tensioner and all is well. It carved correctly. I am sure that this was the problem and has been solved. Sorry, Al gets the beer!!

Back when I first had this problem and it jumped track the one time, I must have changed the bit simply because I thought it was dull, not because I thought it had anything to do with the skipping.

I agree with the need for a feed rate regulation but I also think there should be some way of warning the user when there is too much pressure on the bit and Y axis from a dull bit. It is hard to tell when the bit is dull, especially with these bits from PreciseBit. Even new, these bits carve with fuzzies. After 50 hours the fuzzies look the same. The only tell tale sign of getting dull is the curly cue wood shavings still attached to the lead side of the project; these have a tendency to get removed with a sharp bit and stay attached with a dull bit. Although this is not necessarily true with a harder wood like oak.

I think I will switch to pine for awhile and see how much carve time I get on these bits. I will have to get used to sanding fuzzies!!!:(

[Digitalwoodshop]

Beer:D Y Thank You !!!!

I live for this stuff.... I miss fixing stuff for a living.....

I am like the Maytag Repair Man.....

Good Interaction.....

I was on the CW Pattern Depot today wanting to buy 3 Grape patterns but could not get it to check out.... It's the simple things that drive us nuts...

AL:mrgreen:

[Billions]

I was having a similar problem and upon calling LHR they recommended tightening that belt! I haven't used that machine yet but I see that this may have solved your problem, so I'll try it too and hopefully the slipping will stop.

[Digitalwoodshop]

The belt has a spring on the outside edge and that holds sufficient tension and if the head is skipping a tooth then there is a mechanical reason... Snugging the top screw takes the spring out of the picture, making it harder to skip a tooth.

Bits do dull, wood can be harder than Pine and this puts strain on the cutting process... Do you ever get a Clean Y Rail message?

AL

[liquidguitars]

looks like the classic y overload error from FW 1.134 I would say to upgrade to 1.151 or rollback to 1.133.

Edit:

woops not 1.151 but 1.152
LG

[PCW]

looks like the classic y overload error from FW 1.134 I would say to upgrade to 1.151 or rollback to 1.133.
LG

I would skip pass 1.151 and go to 1.152.:D