trouble with Y axis

[sail]

I've been carving corian without a dust collection system. I stop and vacume the dust out 4 or 5 times on every piece. This worked great for a while. The problem is that the Y axis movement, perpendicular to the key pad , briefly jams. This is most noticeable when the truck is homing or finding the width of the piece or worse yet , when it searches for the bit flag. I tried to help it along and that got me past the problem a total of once.

Although I did not take the machine apart to clean it, I did a very thorough vac and blow. It still stops and starts in a stuttering kind of movement and fails to move far enough to push the bit flag out at least once per run.

There is no dust on the truck rollers or roller bars.

I already cleared the wire that was blocking movement on the Y axis as others have described as a design flaw in my older machine. So that isn't part of this problem.

I noticed that prior to this problem, once the machine was turned off, I could manually move the truck. Now it seems to be stuck tight to the key pad side of the machine. I also note that the carving is not exactly centered on the corian but rather about 3/16 inch off to the key pad side of the machine even though it is definitely set and programed to cut on center.

So my questions are:

Could the drive belts have skipped a tooth making the machine believe that it's not all the way into position?
Could this " skipped tooth" also be the cause of the non center carve ?
Could this be why the truck won't easily move manually?

If so, why does the truck hesitate about mid way when moving on the Y axis?

Could the drive motor be full of dust and cause this?

And MOST IMPORTANT How do I fix this ?

I will install a dust collection system before the next cut so now is not the time for a lecture thank you. shoulda woulda coulda etc.

Any help will be greatly appreciated.

Phil

if it's not one thing after another, it's the same thing over and over.

[Digitalwoodshop]

Your Y problem is caused by the 2 small bearings in the Y Gearbox have gone bad. The Quick Fix is to use a old gearbox off of a old Z Motor... But not many people joining in 2011 have them.... Guys from 2007 do...

So the bearings have failed and are letting the big plastic gear lean toward the center of the machine. I bet when you do the Bit Checks the Y Clicks 3 times too... If it is clicking than the bearings are shot and they have likely worn the big plastic gear's shaft.


Lucky LHR also sells a replacement Plastic Gear... with shaft... I get the bearings in a 10 pack from a variety of sites... You can also get them locally.


This is just one of many places to get the Bearings.... I recommend replacing the Y Bearings when you replace the Cut Motor Brushes at 250 Cut Hours...

And this is just normal wear and tear.... The Y takes a beating.... If you don't replace the Y Bearings then the shaft will wear.... The Machine will run much better with new bearings.

http://www.avidrc.com/product/1/bearings/170/5x11x5-Metal-685ZZ-bearings.html

The bearings come out from each end as there is a ring inside the center.

AL

[ladjr]

This may be a dumb question, but you mention Vacum and blow several times b never lubrication.

[liquidguitars]

Yes what Al said, as a quick way to check the gear box i push down on the the small pulley gear if it has a spring or moves up or down over 3/32" its a good chance the plastic gear and bearings are shot... This push test also work on the zpack.

[fwharris]

I third the Y bearing and gear as your most likely problem.

Easy to verify, remove the Y belt for the Y motor gears. The truck should move easily. While moving the truck pay attention for any bumps, dragging or resistance. The corian dust will pack and build up on the rails and bearing faces. I've had to use a small pick to get some loose. Dust collection is highly recommended for corian carving to help reduce the amount of chips that stays inside the machine. Even with DC one should pause the caving to clear/clean the chips for the belts, gears, rails and bearings.

[Digitalwoodshop]

Find the 250 hour Maintenance Thread and read my long post on the Y Rebuild... I found a Frozen Y and Z Bearing in the process.... They were sliding along the rails and I did not know it... And bad bearings...

AL

[sail]

Al,
This seems like the most complex and involved suggestion of the lot.. It's also most likely to be the correct one. Although the original owner used it very little (no time to figure it out). And my usage has been minimal, it's the corian that makes me think I'm past the easy fixes.

I will follow all links and get started on service right away.
THANKS

[sail]

It's only a few hours of actual use of the machine since I replaced the chuck with the Carve Tight so those bearing are all new. But a good idea to check everything more often than service recommendations when cutting plastic.

[sail]

This may be a dumb question, but you mention Vacum and blow several times b never lubrication.

There are no dumb questions. But in my lifetime I have heard a LOT of dumb answers. You know what ? I haven't checked the lubrication in a little while. That's now on the list too.

[sail]

I third the Y bearing and gear as your most likely problem.

Easy to verify, remove the Y belt for the Y motor gears. The truck should move easily. While moving the truck pay attention for any bumps, dragging or resistance. The corian dust will pack and build up on the rails and bearing faces. I've had to use a small pick to get some loose. Dust collection is highly recommended for corian carving to help reduce the amount of chips that stays inside the machine. Even with DC one should pause the caving to clear/clean the chips for the belts, gears, rails and bearings.

I guess I've been treating my machine more like a date than a wife. Time to start paying more attention if I expect to get what I want.

THANKS FOR THE HELP

[sail]

This is just one of many places to get the Bearings.... I recommend replacing the Y Bearings when you replace the Cut Motor Brushes at 250 Cut Hours...

And this is just normal wear and tear.... The Y takes a beating.... If you don't replace the Y Bearings then the shaft will wear.... The Machine will run much better with new bearings.

http://www.avidrc.com/product/1/bearings/170/5x11x5-Metal-685ZZ-bearings.html

The bearings come out from each end as there is a ring inside the center.

AL

Al,
That site also has ceramic bearings for $10. Would these last longer in our sort of environment ?

[Digitalwoodshop]

Don't know?

A 250 Cut Hour Maintenance Opportunity will really cut down on the problems with the machine.... Not sure the money for the Ceramic is worth it....

AL

[sail]

The bearings come out from each end as there is a ring inside the center.

AL

Al,
I appreciate your help. When I opened up the top and released tension on the Y belt, the gear on the motor moved more than a little. I opened that up and found the spindle of the main gear sheared. I mean severed. I mean part was in the housing and part in my hand. How the hell this worked at all is a mystery. SO.... I took the snap ring off and am now having trouble getting the bearings out. Do I understand you to say that there are two and one comes out each side? The wear on the post may be such that it will not release. Any advice ?
Phil

[sail]

Don't know?

A 250 Cut Hour Maintenance Opportunity will really cut down on the problems with the machine.... Not sure the money for the Ceramic is worth it....

AL

Now that I've been inside the motor, I agree. The bearing isn't always the problem.

[dean448]

I don't use this machine very much. About 40 min into a cut I started to get warnings to clean the Y axis. I was able to get it to go a few times then the Y axis stalled, which aborted the cut. Took the Y axis gearbox apart and the inner bearing came apart. Luckly no other damage and I was able to tap the outter race out of the bore. Just put an order for sealed 5X11X5 bearings on ebay. I'm pretty sure this is from contamination getting into that gearbox.

[Digitalwoodshop]

Good Job !!!

The Y Gearbox takes a real beating.... It is being asked to do a lot of work for many hours... This is why I have started to recommend that everyone plan a 250 hour maintenance and clean and lubricate the machine and at that time replace the Cut Motor Brushes and the Y Gear Box Bearings.....

That lets you catch the Contamination of the Gearbox before it becomes a problem... As I posted above, I found 2 frozen Roller Bearings during my maintenance.

The Happier your machine, the Happier YOU ARE....

The LHR Maintenance list ALSO lists replacement of the Y Gearbox EVERY 250 Cut Hours... You can replace the whole gearbox or clean and replace the Big Gear with Shaft and the 2 bearings...

AL

[dean448]

Thanks Al, Good advice. I don't see many parts listed for sale on their website. Can you contact LHR and get any of these maintenance parts? Like motor brushes.

Also my X axis has a motor excited vibration that seems to resonate thru the frame (when checking length). Works fine but I'm wondering if thats normal?

[fwharris]

The the conference Chris Rawls went over the Y belt adjustment steps. He said all that is needed is to loosen the screw a few turns and then re tighten. He stated that it is self adjusting and you should not need to add any tension to the belt tension plate. This is also in the Maintenance and Repair PDF on page 12.

I know I would add some tension by using a screw driver to push the tension plate over just a bit before tightening the screw. It would be interesting to know how may of us are adding a bit more tension to the belt and maybe we are causing the undo force/factors that are leading to early bearing and gear fatigue. ?????

[AskBud]

54753From the manual.
AskBud

[sail]

Thanks Al, Good advice. I don't see many parts listed for sale on their website. Can you contact LHR and get any of these maintenance parts? Like motor brushes.



When I took the Y axis motor apart, there was some dust and plastic chips that got past the plastic seal. I now see that a regular cleaning is important. That should include lubrication.
All was right ( as usual) there are two bearing on the plastic gear for the Y axis drive. They come out from opposite sides. Use a drive pin and tap lightly once you have removed the snap ring and washer, they'll come right out.
Parts can be ordered over the phone from LHR.

I also now recommend a good dust collection system too. I just bought one from http://www.erwinproducts.com/erwin_products_004.htm The web site shows it working with a common shop vac but I think for most of my cutting, I'll block off part of the intake to keep the suction over the work.
In 10 or 12 days, all of the parts I ordered should be in. I'll let you know how it all works once installed. I think I need a cpl more carvewrights to keep up.

[Digitalwoodshop]

Good Job !!!!

The Clear Plastic cover over the Y Gear Box has a slight leak in the center where the belt is due to the design. Dust Collection will help keep the machine running GREAT for years.

Happy Carving,

AL

[dean448]

Not to sure how well this 250 cut hour maintenance concept would have helped my Y axis motor bearing going out. Turns out the machine had 83 hours on it. Also found that many folks are selling 5X11X5 on ebay that are actually 5X11X4. VBX had what looks like a quality bearing at the correct size. I ended up replacing bearings in both the Y and Z axis.

[Digitalwoodshop]

83 hours... Did you ever manually tighten the Y Belt by releasing the screw on top of the Cut Motor Electrical cover and push the return away from the Y Motor then tighten? If you did, that can cause premature failure.

What kind of cutting do you do? Lots of Corian? Oak?

Thanks,

Just trying to understand... not point fingers....

GOOD find on the eBay junk.

AL

[sail]

PROBLEM SOLVED !! After paying close attention to the advice given here, I opened the Y axis drive assembly. I found a sheared spindle post and so replaced the gear and both bearings. I thoroughly lubricated the machine and it is working well again. While inside, I found a LOT of acrylic shavings. They got past the mounting plate, the plastic protective sheet and the caulking used to hold it in place. I came to realize that stopping every 15 minutes to vacuum and blow out the dust wasn't near enough. That's when I found the Dust Devil from Erwin Products. http://www.erwinproducts.com/erwin_products_004.htm Easy to install and it worked like a charm with just a shop vac attached. I used an aluminum dryer vent tube and an adapter to reduce the 4 inch to 2 1/2 inches.. I thought I might have to make some sort of reducer to help direct the suction over the work piece but there was so little dust remaining I decided that wasn't necessary. Still, the shop vac is noisy and gets hot on a longer run so I'm shopping for a low cost dust collector to hook up in the near future.

I highly recommend the Dust Devil. Everyone should use it to add life to your Carvewright. The price is right too.

Any way, THANKS for all the help in solving my problem.
Phil