Cut Path inaccuracies and dealing with them

[deemon328]

Well, I've got a bit of an issue with cut path. I just calibrated and cleaned the machine and made these two parts. The cutpaths were the best I've ever made...no stairstepping at all and barely a noticable trace where the bit made each depth stop during each pass.

Here's the jig that has a 2" x 3" inside cutpath, and a block to fit in it that has a 2" x 3" outside cutpath. The jig is .04" oversize and the piece is .04" undersized, creating a poor fitting and useless piece. I cut 6 identical blocks like this one on one long board, and they're all identical.

http://photos.yoderwoodworks.com/images/A_2/4/0/5/15042/DSC04599_9b6ca.Large.jpg

So, I'm wondering what could be the issue? Is it possible that my bit isn't seated perfectly straight in the chuck? The reason I ask is that I'm having some difficulty releasing the bit from the chuck and even operating the chuck with no bit in it. I had my bit stuck in the chuck with the quick release up when I tried to get it out just now. I thought I was going to break the chuck, it was stuck so badly. I'm keeping the inside of the chuck as clean as I can and wipe the inside with dry lube with PTFE on a rag to try and keep it rust free. I've also noticed that my 1/8" straight bit adapter is seeing a good bit or wear after only a small amount of usage. I give it a shot of the same dry lubricant every time I use it as well.

When I try to raise the quick chuck, it doesn't want to go up, but if I try and move it a little bit to the left as I move it up, it goes up fine. I have to reverse the process to get it back down all the way by twisting it a little to the right to let it snap down.

For those of you that do cutpaths all the time, do you have these kind of errors, and do you just compensate by changing the size of the cutpaths to adjust for the error?

Is it also likely that I have a chuck/adapter problem?

I think I just put this little dimple on my adapter after trying to get it out this time...

http://photos.yoderwoodworks.com/images/A_2/4/0/5/15042/DSC04605_d20b8.Large.jpg

Other side of adapter, note the wear marks. I don't know if that's a lot of wear or not. This is less than around an hour or two of total usage with this bit.
http://photos.yoderwoodworks.com/images/A_2/4/0/5/15042/DSC04604_c18ad.Large.jpg

[DrBob]

Chris you might want to add to this!

[liquidguitars]

I see some small dings on the bit adapter 2 so yes it should be repalced. You can clean the QC for now, but I would order a new QC asap,

If you have a press, remove the bit for a new replacment adapter and the collets are just $ 4.95 ea. ;) I Locktight the router bit shaft and set screws to bit adapters to be sure that the bit will not ever come loose.

I also see a lot of rust on the adapters I add a drop of light oil and not dry lube on the adapter everytime I change a bit , this helps with the life of the QC parts.

Cool bed project!

http://www.liquidguitars.com\saltdot\DSC04605_d20b8_Large .jpg

LG

[ChrisAlb]

After we just spent a day in a quest to help Andes...lol

Hi deemon,

I think it's easiest to just point you to the post of my findings after testing for a day on cutouts and vectors. I found the machine / Software calculates them a bit differently.

http://www.carvewright.com/forum/showpost.php?p=41918&postcount=28

[ChrisAlb]

Other side of adapter, note the wear marks. I don't know if that's a lot of wear or not. This is less than around an hour or two of total usage with this bit.

If that's after only an hour or two, and as you say your chuck is hard to move, I'd seriously check the chuck. Make sure it's clean and lubed right and moves freely. After every carve I remove the bit and just lift the the collar and let it "snap" down several times. I'm always surprised by how much falls out. After 10 or so carves I use a mirror and flashlight to look up in there. Make sure it's clean and functioning smooth and lube if needed.

Try cleaning and freeing it up best you can. Use either an unmarked adapter or maybe you can rotate the one in the picture and try another couple hours on it. If it gets new marks, the chuck itself may need attention.

The findings I pointed you to of the test I did seem to hold true (at least on my machine). I tried another set of tests today with same results.

[deemon328]

Thanks for the link, but I don't see how that affects me, since both of my pieces were made using cutpaths, one on the inside of the path and one on the outside of the path. If there's something else I should be gleaning from that post, please elaborate. My gap is .04 on each piece(.02 on each face); if I were cutting down the line, I should see a .0625" error on each face. It's not adding up. Those results on the photo you linked seem to vary wildly, and I'm not sure how they apply in this case.

I'm surprised that my adapter needs replaced already after only a couple hours of use. I've got 15 hours on my 1/16" carving bit and adapter and it shows no such wear. It's really strange how all the wear is on my straight bit adapter.

Thanks for the discussion so far.

[deemon328]

Well, I found a little mirror and checked the chuck. There is definitely some impacted dust in there. If I could grow another arm, I could take the mirror, light and toothpick and clean it out :) My chuck doesn't snap at all now, so I'm thinking those impacted areas are holding things up.

I'll post back later with my results.

[ChrisAlb]

Thanks for the link, but I don't see how that affects me,.....
Thanks for the discussion so far.

My apologies deemon, I misread your post. But the funny thing is, just 3 days ago I tried (again for accuracy testing), Seeing how well simply flipping the cutout on a circle and using the drill hole would make a plug fit the hole. I found it surprisingly close... LOL Took a piece of cherry flooring, and cut a 1.5" plug.

First picture, The plug using a 1.5" circle and "Outside" cut path.

Second picture, (Board upside down to show the gap better), The plug inside a 1.5" "Drill" hole.

Third, The plug inside a 1.5" circle "Inside" cutpath.

While not "Perfect", I was rather impressed with the results.

[hotpop]

deemon328

Try an old tooth brush, works great and it a lot faster.

[Dan-Woodman]

Try the same thing with the tapered carving bit.
Thats how I did my ovals that I posted a while back, and surprisingly they fit really good.
If you cut two ovals , One inside and one outside , then flip one after removing tabs.
Very little sanding.
later Daniel

[deemon328]

That's a great tip, Dan. Thanks!

Well, here's what I did to my bit adapter:

http://photos.yoderwoodworks.com/images/A_2/4/0/5/15042/DSC04609_c0e46.Large.jpg

I polished it up in the hope that it woudn't stick. Unfortunately, while it looks great, it doesn't do any good at all. I can push the quick connector up to get the bit on, then take the bit out several times with no problems. As soon as I run a project, in my last case a 2 3-minute cutpaths, the quick chuck won't let me raise it up and I'm stuck. I thought that I might be able to immobilize the chuck, but I didn't have a wrench to fit the nut, nor did I have that square tool to stick in the flexshaft hole. Eventually, I kept trying to lift the quick connector and spin the chuck a little and repeat until the bit fell out. I ran the 1/16" bit on a 20 minute project and the bit popped out just fine and the chuck pushed up with no problem. I'm giving up for the night.

Chris, would you say that when you do your cutpath testing that although your sizes may be a little off, at least they are consistent? I'm getting fantastic consistency and straight clean walls on cut paths, they're just a little undersize. I can live with making every outside cutpath .02" bigger and every inside cutpath .02" smaller if it stays consistent.

It's been fun show and tell tonight, thanks everyone!

[Digitalwoodshop]

I keyed on the little ball bearing mark in that first picture... That told me the metal to metal contact pads on the QC are worn. A replacement QC is in order. You can put it off but you will BB mark every bit holder you put in.... I had a brand new holder put BB marks in the holder with less than 30 minutes of cutting. The longer you wait the more holders you waste at $? each.... I parked my machine the other day when I got the BB marks and used my back up machine. Misplaced the new Square Drive bits from RJ..... Need to find them to change the chuck.

Good Luck,

AL

[deemon328]

Thanks for the update Al. Is this why I'm having trouble even operating the quick chuck?

[deemon328]

Update:

I started using 3-in-1 oil on the adapter before placing it in the QC. The QC has been releasing properly since then.