Inconsistent carving depth

[Gerald Bennett]

Well I was going to start with the fact the red handle doesn't stay locked, but saw in other threads that the handle is pretty much useless as several people never use it.

I do have the handle pulled out but it moves as the carving head is moving across the piece, going in as the truck moves away from the keypad then back out as it moves toward the keypad.

The first 2/3 of a rectangular carve region look smooth and level then the depth visibly changes with each pass as if the head is vibrating up and changing the depth, any idea what would be causing that since the locking lever doesn't seem to be needed to keep the head down during carving?

There are 3 projects on this one board and the second is currently running, not enough of it to see if the depth is steady in it or not yet. The board was not run through a planer but it looks better than the changing carve depth would indicate, its a pine stair tread ( hey they are cheap to test with and easy to get :cool: and usually an even thickness)

[Wilbur]

I had this happen a couple weeks ago and found the Z truck bearing was loose causing the truck to wobble from time to time.

I also found after I fixed that, that my bit was dull, causing the bit to slip. I replaced with a new bit and everything is working just fine.

These are a couple things to check but there could be other things.

Wilbur

[Woodhacker]

The board was not run through a planer but it looks better than the changing carve depth would indicate, its a pine stair tread ( hey they are cheap to test with and easy to get :cool: and usually an even thickness)

I would like to know where you find pine stair treads. I'd love to do some carves in those if I knew where I could get them. Thanx!

[Digitalwoodshop]

Looked at your 9 posts and you are still learning all the tips and tricks to using the machine.

I must ask if you followed the 7 inch rule of wood.... Was the board so short that when it popped out from under the roller and was now being held only by one roller. Like riding a bike with one hand...2 is better...

The board comes out from the roller and lifts toward the bit and that is why you get a difference...

If you are using 7 inches extra of real wood to stay under a roller.....

Lots posted on this...

Designer board 10 inches long, Real wood 17 inches so both ends stay under the rollers and are held FLAT to the table..

SO if you ARE using 7 inches of extra wood then it could be a loose bit in the Bit Holder... Loose Z Motor Screws, like said above, a loose Bearing....

If you have not read Tips and Tricks and use the Search with a " " like "Depth change"

Good Luck,

AL

[jab73180]

hey AL could it also be the head pressure is too loose?

[Gerald Bennett]

The step came from Home Depot, they are alright for learning but often have hidden knots in them, they look great on both sides but you find some nasty knots when they are carved.

I used a board that was the full 48", the design is only on a virtual board of 38" so there was 5" on each end. ... definitely still learning which is why I use the steps, can get tons of them. When I get to making keeper carves I will have to consider making my own to try to reduce the hidden knot issue

I attached an image of the project, the ends had to be cropped to meet the forums size limits. Area "A" was the stepped area, each pass was slightly shallower than the last and seemed to be level across the cut, it appears each time the board advanced the bit came down a little less until the pattern finished then looks right for starting the next pattern.

Area "B" just didn't touch the surface at all so some letters didn't carve, Area "C" also didn't carve at all but the area inside the circle cutting area did. Actually looking closer at the circle the left side steps down to the proper level by the time it reaches the lettering so it was a little high and gradually came down over several passes then other than the letter areas seems to be smooth.

Tomorrow I can look at the Z truck

[Digitalwoodshop]

Pictures of the actual board would be good too.

Things to check....

Head Level. Install a board and use the Z Data and bit to touch 3 areas of the board left to right or measure it.

Remove the Bottom of the machine and check the tightness of the bolts on the bottom of the machine. Loose smooth rods that the heads slid on can become loose. Then sawdust speed bumps lift the head.

AL

[AskBud]

Another thing to check.
Place the edge of a yardstick on board, length & width, and see if the board of perfectly flat. If it is bowed or cupped, you will notice it in your carve.
AskBud

[Gerald Bennett]

Ok, lets try these ...

http://i149.photobucket.com/albums/s43/curbbit/PICT0005-4.jpg

In this first one you can see some scratches where the letters are missing, the begining of a M and end of a T are visible and part of the E is missing

http://i149.photobucket.com/albums/s43/curbbit/PICT0004-4.jpg

In the second, the area with the letters is the correct height, just left of the O and W you can see a line, that area is raised for some reason and finally

http://i149.photobucket.com/albums/s43/curbbit/PICT0003-6.jpg

just to the right of the knot you can see lines, each is slightly higher than the previous but seems to be consistent across the width of the board. I tried to get a shot from the end but it wouldn't come out.

I hoped to get a chance to go to the in-laws to plane the board, it will still be thick enough to run again so wont have to waste the board :) but ran out of time so that will be later this week.

I cleaned the machine a lot today to try to get all the sawdust out of every hiding place, the truck doesn't wiggle when I try to move it and the travel seems smooth in both directions. Will check the z readings after I am sure I have a level board to work with.

I suspect slight cupping might be causing the missing letters, they are quite shallow, but not sure that would be the answer to the lines visible in the third image as consistent as the stepping appears to be... I gotta save my pennies and get a thickness planer to get serious about this

[jackth58]

I am having the same problem. The first 3 or 4 projects went well but now everyone varies in depth across the board(from front to back). I am using a planed whitewood board with plenty of extra on the ends. The text I am carving at .062 depth with a 60 deg v grove bit goes from correct depth to invisible across a distance of 8". I have cleaned the machine well. I thought that the back headscrews were binding allowing the head to be tilted, but after cleaning I still had the problem. I have tried 5 times to get a good carving without success. I am certain that the board is flat and down properly. The z truck seems to be tight and I am at a standstill. If anyone comes up with a solution to our problem let me know!:( P.S. When checking the z height with sensor checking opion the board shows a .075 difference in thicknes (or height) even thoug it measures the same with caliphers. IL'm thinking that the y rail is not parrellel to the board surface. Does anyone know how to adjust the y rail?

[Eagle Hollow]

I am having the same problem. The first 3 or 4 projects went well but now everyone varies in depth across the board(from front to back). I am using a planed whitewood board with plenty of extra on the ends. The text I am carving at .062 depth with a 60 deg v grove bit goes from correct depth to invisible across a distance of 8". I have cleaned the machine well. I thought that the back headscrews were binding allowing the head to be tilted, but after cleaning I still had the problem. I have tried 5 times to get a good carving without success. I am certain that the board is flat and down properly. The z truck seems to be tight and I am at a standstill. If anyone comes up with a solution to our problem let me know!:(

Jack,

It sounds like the head is out of level.