Z stall after screwing up pattern!

[Rkoonz2]

Hi, please help! I have been trying to figure this out for about a week or so, it works fine for a wile then screws up!
I have a C carvewright with 150 hours cutting hours. and about that in scanning hours its past the warranty but I didn't use it for a wile after I got it. I have used the dust collector on it from day one so it is still nice and clean. I only carve pine... Im using designer 2
Im using the new 2" bit (always at best quality) to carve out a 4 piece bird house pattern I made and scanned in. the first time it carved about 75 percent of the way and then it cuts a line through the pattern toward the key pad and came up and then plunged back in and stops at a z stall...
I tried the same pattern again after adding a 0 carve region over the already carved spot... it started a little over the last carved area and was a little off set (carve was already screwed up, so I let it go) it carved for about 20 min and did it again...
Next I was carving a pattern I got from the pattern depot and I came back and it had a error, I forget what one but the flex shaft was frozen, the bit side had wound that guide spring around it and rewound some of its self, the cut motor side snapped... it did not show any indications of going off the pattern this time.
I had a almost new flex shaft on my older machine that I used to fix the newer one.
I redesigned my bird house pattern to do each piece one at a time, I reformatted and flashed a different memory card and this time it got about 85 percent of the way done before doing the same thing.
To top it off I had a dream last night that I tried again and I came back to check on it and it had snapped the bit!!!!!
So now Im here before my dream comes true!


just to clarify these pics are of two different carves that it screwed up on... its done it two other times as well... I thought it could have been the pattern, but it does it a different spots every time...
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[Digitalwoodshop]

It is my belief that this is actually a "Y" problem not a "Z" problem... Normally I would say the 2 685ZZ Bearing s are shot but with 150 hours... not sure... but something is loose in your Y and it is loosing steps...

Dirty Y Encoder
Dirty or Loose Y Belt
Loose Y motor screws.

Seeing the machine cut into the DENSE KNOT then TILT..... Loose Y....

AL

[lynnfrwd]

What is all of that other stuff on the board (grey) Could it have been the knot?

[Rkoonz2]

Hi, thanks for responding! if your talking Y motor then your looking at about 300 or so hours... I have done a lot of scanning! I will go check it out and see what I can find!
I thought the knot was the problem after seeing that photo but it does it with or with out knots. but then again it might be something that helps set off a more or less random error...

Thanks,
Rich

[Rkoonz2]

The gray is concrete floor... that is the hole from one of the other two bird house parts it carved just fine... it failed on on the 3 part of 4... all one long carve tho, for that one. after I tried just one part at a time... I took the finished ones out, so in the pic there is just a hole so you can see the floor its laying on.

[Digitalwoodshop]

So at 300 hours my first choice would be to replace the two 685ZZ Bearings... Remember we recommend replacing them at 250 cut hours but if you are using the machine for deeper and harder cuts, they could fail sooner... And remember when they fail they grind the shaft thin on the big gear and until they stock them again you then need to buy a new motor or gearbox.

And have some cut motor brushes ready too for 250 cut hours too... Brushes are cheaper than a snapped bit when the motor stalls.

:) AL

[Rkoonz2]

So at 300 hours my first choice would be to replace the two 685ZZ Bearings... Remember we recommend replacing them at 250 cut hours but if you are using the machine for deeper and harder cuts, they could fail sooner... And remember when they fail they grind the shaft thin on the big gear and until they stock them again you then need to buy a new motor or gearbox.

And have some cut motor brushes ready too for 250 cut hours too... Brushes are cheaper than a snapped bit when the motor stalls.

:) AL


I only have maybe 20-30 hours on the 2" bit... and only because I have to keep doing them again! Iv been using best quality on pine to keep the stress down... I guess scanning should not put a lot of stress on it like carving... I took the Y motor off and checked it out... everything looks and feels tight, just like new... I had to tap it just to get it to slide out, I call that a tight fit... no rub marks... Im a big believer of the dust collector attachment! it has kept it nice and clean. thanks for the parts tip, iv done a lot of problem solving with my other older carvewrights (that were given to me) and have a good amount of extra parts for them...

here are the pics of the Y motor.

please let me know what you think I should try next.

Thanks,
Rich


79790797917979279793

[bergerud]

I think it might be as simple as a y belt slip. I suggest you re-tighten the y belt. (One could also put a felt pen mark the y belt and y motor sprocket just to confirm if it slips next time.)

[Rkoonz2]

I think it might be as simple as a y belt slip. I suggest you re-tighten the y belt. (One could also put a felt pen mark the y belt and y motor sprocket just to confirm if it slips next time.)

I will give it a try, could it be the encoder disk slipping... I didn't take the back off of the motor because I don't know how I would check that... I did have a carve I did with the 1" bit before all this started happening that moved the second half of the carving over a 1/4 of an inch...
I did loosen and re tighten the tighten for the Y when I put it back in... I will start the carve again... its a 5 hour carve, so I will let you know how it went in about 5 hours.

[bergerud]

I do not think it is an encoder problem. Put that reference mark on the y belt.

At times, I have had to "help" the y tensoner to make the belt just a little bit tighter.

[Digitalwoodshop]

In your one picture I see only one 685ZZ Bearings. Does the Gearbox have 2?

AL

[Rkoonz2]

In your one picture I see only one 685ZZ Bearings. Does the Gearbox have 2?

AL


Yes it has two, it all looks like new. I think the Y tightener must have been loos. I helped it a little and set the screw. I carved the whole pattern without any problems! Thank you all for all your help! made my day! im scanning tonight and will be doing the other 3 parts of the bird house tomorrow.