Problem

[Wilbur]

Have been carving 14" round two side clocks.

Just started a new carve, The carve on the back for the clock movement to fit into carved good. Flipped the board for the front carve.

Starts out good then about 1/4 way through the carve things started to go wrong.

Carves get off center and carving different than the program calls for.

I get no errors or have no problems as for as the machine YZ movement goes.

Anyone have any suggestions on what the trouble might be.

I have re programmed the memory. card and get the same pattern.

Thanks
Wilbur

[AskBud]

My guess, is that you do not leave enough "Rail" on the keyboard side for the second side to track.
We need to see the MPC and know the width of the actual board you use as well.
AskBud

[Wilbur]

The board is 14.25" by 21" long that included the 7" for the length. The carve is 14.25" by 14.25". the board is .75" thick. Put it on another card and running it now, and so far it seems to be doing alright.

We've done around 20 of these clocks using the same MPC and it has always done fine till this.

Thanks for the help!!
Wilbur

[DocWheeler]

Wilbur,

Sounds to me like you might have some dust in your Y encoder.

[Digitalwoodshop]

Sounds to me like you have a loss of contact with the brass roller....

Either you cut away some of the wood on the back that normally contacts to the brass roller.

What does the edge look like where the brass roller contacts AFTER you flip the board over.

You are getting errors in the length or X Direction Correct?

Masking tape will help as you lost contact with the brass roller.

AL

[Wilbur]

Where is the Y encoder?

The edge look's the same. I get no errors at all.

After I put the program onto another card it is doing fine but I don't know if that was the problem or not, nothing that I can see.

Wilbur

[DocWheeler]

Wilbur,

My understanding of your post was that the errors were in the Y direction (to-from the keypad), if the errors are on the x direction (skipping or not moving the board) than Al is going in the direction that you need.

The Y encoder is under the black cap on the back of the Y motor (closest to the keypad). There are several posts about it. Dust gets on the small disk and the reader counts it as index marks so the motor moves to the wrong position.

[www.go3d.us]

Can you post the pic of the carved piece?
Thanks.

[Digitalwoodshop]

If the error is in the Y or left to right direction then I say it is a dull bit...

OR the board popped out from under a roller and the board raised into the bit while it was going left to right or right to left... Or did you say you had an extra 3.5 inches to stay under the roller.... If so... Dull bit.

Close up pictures of the board with X and Y Direction noted would be good.

Are you cutting the area to put the clock on the back of the board? I gave that up and use a 3.5 inch bit from Klockit.com in my drill press.

AL

[Wilbur]

The picture shows what I am saying, left to right. Have already carved the back and started the front. Carving starting from the left, starts out good then starts to get crazy and carving as if it has no program direction.

I got NO ERRORS anytime. The Y Z truck moving good.
The board is flat and square with good edges and service.
Has a new bit with 20 hr .
I re programmed the card and the same thing happened.
I put program onto another card and everything is running good now. I am into my 2nd carve.

I understand the Y sensor now. It counts rotations. Nothing wrong here.

Thanks
Wilbur

[DocWheeler]

Wilbur,

It appears that you are carving on the end of the board without the 3.5" to stay under the rollers and the board is lifting off the brass roller.

Al was correct in sensing that the errors were in the X direction rather than the Y direction (where I have had problems).

[Gerald Bennett]

Since putting the file onto a new disk solved the problem then it is likely the flash card developed a bad sector. Happens sometimes even though flash drives are pretty tough so having a spare card is always a good idea

[Wilbur]

I should have said that I had cut the ends of the board off in order to salvage some of the board, after the bad carve.. This is why the board looks small. It was 14.25" by 21" to do a 14" X 14" carve.

Is there any way to check the card? Well I guess I could try it on another carve.

I am now thinking that is the problem unless I can come up with something else.

Thanks to all for the help

Wilbur

[seabass]

I don't get it. If the carve is 14.25 and the board is 14.25 how could it ever work?

If I carve something 14.25" wide that board better be at least 14.75 wide or there are going to be problems. Actually, I always make the board a minimum of 3/4" wider or more than the carving.

I have always had issues when pushing the maximum width on my machine.

Can't you can get the carving to 13.75" wide and use a board that is 14.25" wide? I bet it will work better. At least on my machine it does, it does not like super wide boards for whatever reason.

[Wilbur]

Ok. You are right. I said it different but mint the same as you said.

The clock after cut out is 13.75". With the routing around the edge the cut takes up about 14.120" of the board 14.25". This cuts it close and some times the routing will clip the edge.

If I had not had a second card I would still be looking for the trouble not thinking that it may be the card.

I am not 100% sure that is the problem but with another card I am on my third carve now with out a problem. Just lucky I had another card. I would have not though of a bad card.

Wilbur

[TIMCOSBY]

I don't get it. If the carve is 14.25 and the board is 14.25 how could it ever work?

If I carve something 14.25" wide that board better be at least 14.75 wide or there are going to be problems. Actually, I always make the board a minimum of 3/4" wider or more than the carving.

I have always had issues when pushing the maximum width on my machine.

Can't you can get the carving to 13.75" wide and use a board that is 14.25" wide? I bet it will work better. At least on my machine it does, it does not like super wide boards for whatever reason.

across his board to carve all the way to the edge. you wouldnt want to cut all the way through on the keyboard side. i do 14.25 all the time no problem as long as you got some flat surface of the board uncarved as he does. you couldnt do a carve region the entire width because of the rollers.