Cut out (mis)alignment problem +

[scgrout]

Hello Forum Members,

I have a problem with cut out accuracy that I could use help with. When I attempt to cut out designs from a nice flat 1/2 thick material, about 50% of the time the cut path is slightly or even way off on first or second passes. For example when trying cutting a gear design, the machine will start out fine, cut many teeth nicely and then somewhere mid-pattern it will lose its way and go slightly or even way off track. Or, the first pass of the cut out is fine, but the second pass is slighly or significantly mis-aligned with the first pass. This happens with gear design referenced, or any other cut out I attempt.

I searched/read forum for cut-path misalignment and did not seem to find this specific issue. I have checked that the board is flat/smooth on the bottom and is engaging the brass rolling sensor well.

Two other issues I could use your insights on. First, on 100% of the jobs run I get a check motor error just before cutting begins a few seconds after motor start. I just hit enter and the job starts ok from there every time. Any ideas?

Finally, when doing cut outs again, the machine frequently gets stuck in an" infinite loop" looking for the bit. It will home, correctly touch the center of the registration "flapper" on the right, find surface, then ask for cut bit and start all over again. It will follow this cycle endlessly. The only fix I have found is power-down/power-up and even this does not work every time.

Sorry for the lengthy post. Any help would be appreciated.

[pkunk]

Hello Forum Members,

I have a problem with cut out accuracy that I could use help with. When I attempt to cut out designs from a nice flat 1/2 thick material, about 50% of the time the cut path is slightly or even way off on first or second passes. For example when trying cutting a gear design, the machine will start out fine, cut many teeth nicely and then somewhere mid-pattern it will lose its way and go slightly or even way off track. Or, the first pass of the cut out is fine, but the second pass is slighly or significantly mis-aligned with the first pass. This happens with gear design referenced, or any other cut out I attempt.

I searched/read forum for cut-path misalignment and did not seem to find this specific issue. I have checked that the board is flat/smooth on the bottom and is engaging the brass rolling sensor well.

Two other issues I could use your insights on. First, on 100% of the jobs run I get a check motor error just before cutting begins a few seconds after motor start. I just hit enter and the job starts ok from there every time. Any ideas?

Finally, when doing cut outs again, the machine frequently gets stuck in an" infinite loop" looking for the bit. It will home, correctly touch the center of the registration "flapper" on the right, find surface, then ask for cut bit and start all over again. It will follow this cycle endlessly. The only fix I have found is power-down/power-up and even this does not work every time.

Sorry for the lengthy post. Any help would be appreciated.
1/2" stock is borderline for the CW, you might try using a sled. Also check your roller pressure with a bathroom scale at 80 #.
The check cut motor error is a glitch in the current software version-we all have it.
As for the bit finder glitch-that's an odd one. You might have to call CW tech support. First try reformatting the card & load a new project.

[Digitalwoodshop]

The brass roller tracks the wood location and I gave up doing quilt rack cut outs. The stepping was in my case caused by the smoothness of the wood and slipping of the brass roller.

More than one click down pressure could cause the sand paper belts to be pressed hard down onto the plate and making it harder to drive the wood. Lumps of dust on the rubber rollers could cause drive problems too.

Good Luck,

AL

[Jeff_Birt]

The mis-registration of the cut-out has commenly been called 'stair-stepping' here on the forum. It caused by the board slipping due to sawdust buildup under the roller and/or a long board without any extra support rollers. I found that if I carved smaller projects and vacuumed the machine out before doing the cut out it would work fine. I have since added a down draft dust collection / air blast system and have had no trouble since.

If your stock is just under 1/2" it could be throwing off the machine, measure it to be sure. It's also a good idea to check the down pressure as others have said.

[mtylerfl]

Hello scgrout,

You may want to check your outfeed rollers too (misalignment can cause stairstepping).

If a board is under 36" long, I just lower the outfeed rollers down to where they don't touch the board at all with no problems whatsoever.

[scgrout]

Thank you all for the fast responses, I appreciate it.

I will test the downforce. I do blow out all dust prior to each run.

Thickness of stackup is 3/4 inch, not the 1/2 inch I mentioned. I actually am cutting parts out of 1/4 inch plexiglass mounted on a 1/2 inch board with ample carpet tape. Plexi stays very firm/aligned to board. Whole set up is 24x11 inches, so pretty small parts. When it works, the parts are beautiful, very smooth, very accurate. Of course when the y-axis slips, I get a lot of scrap.

Thanks, Scott

[pkunk]

Thank you all for the fast responses, I appreciate it.

I will test the downforce. I do blow out all dust prior to each run.

Thickness of stackup is 3/4 inch, not the 1/2 inch I mentioned. I actually am cutting parts out of 1/4 inch plexiglass mounted on a 1/2 inch board with ample carpet tape. Plexi stays very firm/aligned to board. Whole set up is 24x11 inches, so pretty small parts. When it works, the parts are beautiful, very smooth, very accurate. Of course when the y-axis slips, I get a lot of scrap.

Thanks, Scott
One more thing ;) (in my Columbo voice), check that there is no gear slop in the sandpaper rolls. Push on them like you're trying to turn them. If there is the gears may be loose & out of adjustment.

[scgrout]

Thanks again for all your help. I can see that this is an active forum and this helps users quite a bit.

I checked the sandpaper roller tightness, is good and tight.

I did threee things that seemed to help. First, as suggested, I disengaged the front roller. Second, I tightened the crank down a bit harder than the clutch allows (this can be done by pushing the crank in and turning just a bit more). Third, I put a line of two layers of plain masking tape on the underside edge of the wood that contacts the brass roller sensor to increase engagement.

Have done several cut-outs and no "steps" so far.

Thanks,

Scott