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Jon Jantz
01-02-2007, 02:17 PM
I am having a problem with cutting out an object using a cut path. If I cut out a shape, it cuts perfectly on 3 sides of the object, but one side gets a stair-stepped effect. This is caused by the machine not following the exact same path on one side of the object. As it makes it's way around the other 3 sides it is aligned perfectly.

This does this on any shaped item. Square, oval or odd-shaped. They all have the stair-step syndrome. If I am looking at the control panel of the machine, this happens only on the "RIGHT" side of the object. Left, Top, Bottom are all perfect.

Any clues???

I'm attaching a picture to explain it better.
Thanks for any help.

http://www.100percentfeedback.com/Edge%20Problem.jpg

dspeers
01-02-2007, 03:09 PM
I just saw this happen on a rectangular piece I made last night - it was the first square cut I've done. I wasn't sure why it was there as I hadn't seen it on any of the round pieces I've done.

Another thing I noticed with this stepped cut was that the top cut was the short one. The proper cut length was on the bottom step.

Dan

BobHill
01-03-2007, 08:48 AM
It would appear that your belts are moving when they shouldn't on that edge cut. Give CW a call on this one, as it might take some type of technical adjustment they can walk you through.

Bob

ditchdoc
01-05-2007, 01:14 PM
I've always wondered why people use the CW to cut pieces. My table saw, bandsaw, chopsaw and router all do this job quicker than the CW, and is less wear-and-tear on the CW. The accuracy of the CW allows one to design for cutouts with the "proper" tool unless you are doing some intricate filagree. Just wondering.

Jeff_Birt
01-05-2007, 01:23 PM
I do it because you can do somethings else while the machine does the whole piece. When it's done all you have to do is pop it loose from the tabs and do some sanding.

Jon Jantz
01-05-2007, 05:08 PM
I've always wondered why people use the CW to cut pieces.

I use it to cut out shapes because I DON'T HAVE A SCROLL SAW OR BAND SAW. Besides if I do a nice shaped sign panel, why should I pull it out and manually cut around the complicated curves when this machine will do it perfectly?? (When it works) And if I can't cut shapes because it's gonna wear the machine out prematurely, then it's going to wear out from my carving also... at which point I'll throw it in the garbage and get a ShopBot.

I bought it to carve AND CUT OUT shaped signs, which it is designed for and advertised as doing.... I guess I just thought maybe it should work.

(Oh, by the way, this post was asking for help with a specific problem, did you have a suggestion? Thanks.)

Jeff_Birt
01-05-2007, 07:02 PM
I made up these two simple projects to see what was causing a problem I was having trying to use the cut out tool with stock mounted to a fixture. They both cut out a rectangle, one with the cut out tool the other with the rout tool (with tabs manually left in the middle to keep the part in place). Try running a test with each of these to see if you get the same effect.

You might also chaek which software and firmware versions you are running and try reformatting you memory card, which (I think) will also reinstall the firmware on it.

BobHill
01-05-2007, 07:55 PM
Jon,

You didn't say if you've contacted CW or not to see if they can walk you through your problem (which sounds like a mechanical adjustment). I can talk you into how to check a few things, but since you have the warranty, why not check with the real guys for this? Also if you think it's your design, just post the mpc file and someone can check it for you on their machine to see if it's the design or machine if you aren't sure. I'd say, however, it's an adjustment problem most likely on your machine, like perhaps your gears might be slipping at some point, which would account for the belt not traveling properly on each cut.

Bob

dspeers
01-05-2007, 08:12 PM
For my issue I did send them an email and got back a couple of suggestions of what to look at.

Mainly that the little tracking wheel may have lost an exact understanding of where the board was, either because the board had a pocket/hole/warp or something similar, or perhaps something wrong with the wheel itself.

I'm going to try two cuts, one based on a cut-path, and another letting the machine cut the board to size to see if there is any difference.

For my issue it was based on a cut-path.

Now to find some scrap wood I can test with....

Dan

BobHill
01-05-2007, 08:28 PM
Dan,

Check your inboard wood edge to be sure it's square (or very close to it) and the edge itself doesn't have any holes, and I'm guessing that it's not the traction wheel (if it moves freely when you move it by hand). I'm still guessing that it's more likely to be a slipping gear that drives the belts, which means removing the right side panel to check it. But perhaps it would be best to give the CW people a call to see if they'll talk you through checking it. No knowing your mechanical skills, I'm a bit hesitant in going further, although it's not hard to do.

Bob

Charles M
02-04-2007, 01:21 PM
Did anyone find the real cause of this problem? I have made 3 different projects with cut outs and only the first one worked correctly. I have this same stair stepping problem on the other two and it is destroying the carving by cutting into the leading edge. I am also concerned about breaking the bit since each pass is in new material and the bit is working harder and harder until it finally takes a full cut 3/4" thick (in Maple) on the final pass. I desperately need to carve and cut out a piece TODAY that is correct. Please Help!!!!

HandTurnedMaple
02-04-2007, 01:33 PM
This happened to me on my first project. The only thing I can think of is that it wasn't "under the rollers" and my tables were not yet aligned, so the edge of the board was slightly cocked upwards.

Charles M
02-04-2007, 01:34 PM
Thanks for the quick reply. I'll check the tables again.

pine acres woodshop
02-05-2007, 11:57 AM
I just had the same issue,I was cutting out a rectangle and each pass on the ends was offset by about a 32nd or more, after giving it some extra thought and reading these post, I believe that the problem is not with the machine but with my method, on my piece I did not select to stay under the rollers and the piece cutout was close to the edge, so I believe that every time the piece left the back roller (losing half of the support) it would tilt or shift a little causing the sensor to lose original tracking of the board, so for my next time I'm going to have the extra 7" of material. I hope that solves the problem. I'm going to try here in a few minutes, I'll let you know the outcome. I've never had this problem before, but I always had the extra material on my other projects, hope this helps.


Mark

pine acres woodshop
02-05-2007, 04:01 PM
All is well, problem solved. Having the extra material helped.


Mark

Digitalwoodshop
02-05-2007, 10:24 PM
I think you hit the nail right on the head with this problem.... The roller and the sensor with the short board tipping up just enough to lose contact with the roller and losing the true position of the board. If anyone has the stepping problem with extra wood always under the rollers let us know. This problem just might be solved....
Excellent Observation !!!! Take a bow !!! :D :idea: :D :idea: :D :idea: :D Thanks !!!

AL

BobHill
02-06-2007, 09:37 AM
Have you thought of removing the trays on each end? Not only do they get in the way, but really are of no use except to put things when you aren't using the machine. That's what CW does, and I now see how true it is.

Bob

Charles M
02-06-2007, 01:31 PM
Bob,

Do you mean remove the stock support rollers? Turns out they were the fix for my problem. For feeding a board longer than 3 feet they were necessary. I'm thinking of making out feed tables with roller balls for longer stock.

BobHill
02-07-2007, 09:34 AM
Charles,

No, no, not the rollers, the whole tray on each side (silver that fold up). If you've seen the instructions, you have to be sure that the leveling bolts under the tray have to be set so the trays are NOT higher than the drive belts or the wood can be lifted away from the board travel button. But, since the trays are not of real use anyway, why not remove them (as the CW people do on their test machines .... ask the Bard), which then won't give that problem and other being in the way problems.

Bob

HandTurnedMaple
02-07-2007, 10:03 AM
That doesn't sound right to me Bob. Those trays do something for me, they support the lumber not long enough to use supports under or when the longer boards are halfway through. And I know they are supporting it because the rollers at the end roll when the workpiece is advanced. To me it doensn't make any more sense than removing the infeed/outfeed trays from a planer or a drum sander.

BobHill
02-07-2007, 10:16 AM
Maple,

If the wood is long enough to need additional support, you need an extended external bearer in any case, as you would for a table saw. That's the way it was explained to me and seems to be the case, as anything up to and some over 24" works just fine without a brace from my experience so far after the tray removals.

Bob

HandTurnedMaple
02-07-2007, 10:25 AM
Well, it still sends cold shivers up my spine. So I will have to go stubborn on you. :!:

BobHill
02-07-2007, 10:34 AM
Not a problem to me, certainly, Maple. Just be sure the leveling bolts are properly set though.

Bob

Malfunction
02-11-2007, 08:58 AM
i have been having this stepping problem too. i think i'll remove my tables and see if it clears it up. thanks for the suggestion bobhill.

Charles M
02-11-2007, 09:24 AM
My stepping problem reappeared yesterday so I got some roller stands ($13 each at HF) which helped a LOT on boards over 36". I also noted that if there is any cupping to the board make I need to make sure the crown is up (higher part is in the middle). This ensures that the edges are against the brass roller between the belts (the part that measures the distance traveled). Now I am carving 5' long boards with steps that are almost undetectable and easily sanded out. HTH.

Ron Baird
02-11-2007, 02:51 PM
I have had this problem reciently. It is caused by too low a head pressure.
Check it with bathroom scales it should be 80 lbs. If you cut hardwood with this condition you will break a cutting bit. I reacommend doing most of your cuts with a 3/16' or larger bit and allow for the wider bitin your measurement. :D

Ron Baird
02-11-2007, 03:11 PM
Head Pressure
Check it by placeing bathroom scales under the head and crank the head down until the clutch clicks several times. The scales should read 75-80 lbs. If less lublicate the four corner posts and the two crank down screws. If this does not give you a good reading then remove the crank handle and put some spacing washers behind the clutch spring or stretch the spring a little longer or both until you get 80 lbs pressure. I found some small circlips that would fit as spacers.

jlitz
02-11-2007, 03:56 PM
After a couple weeks of relatively simple projects without issues, I started planning a project requiring rather elaborate cut patterns. After a few test pieces cut successfully, I ran a few more tests after removing the built-in support trays. These test boards where 24.5" L x 7" W x 0.75". In all cases when the tray support was not in place I would experience the stair-stepped effect. However, a board 13.5" in length did not experience any issues.

For me, when the tray support is in place and the tray height is set correctly (high enough for the board to slide smoothly on the tray and hit the rollers), I no longer experience the stair-stepped effect on relatively short boards (24"-36").

http://www.nocarrier.com/carver/BadCut_1.jpg