What is "stuck back roller"?

[cestout]

Sometimes I get check for stuck back roller, part way thru a carve. I thought that the rollers were either compressed or not. So what causes this, and is there a way to check it without aborting the carve to remove the board? It just happened again, enter to continue worked for one pass, so I stopped the carve, lifter the head and blew out the back roller switch. I restarted the carve and of course it matched up perfectly and is still going, but I lost over a half hour of carving time.

[bergerud]

When you clamp the head down on a board, listen carefully for when the rear roller switch clicks. On my machine, it clicks long before the board is clamped. If yours is the same, it could not unclick during carving. In that case, it must be a wiring or connection problem.

[Digitalwoodshop]

3 Mechanical things to look at..

1. Remove the Keyboard side of the machine careful of the keyboard wires as they rip easily. Two screws facing up hold a plate that the roller rests on then the head is off the board and the roller is uncompressed. What happens is that dust builds up on the flat plate when it gets un compressed it presses this into a fine layer like Filo dough. Eventually it gets thick enough that the head un compresses but is resting on the packed layer of dust and does NOT let the Switch fall into the slot telling the computer that the head is un compressed.

Holding the roller UP while blowing helps but eventually you need to remove the Keyboard Side and blow it out from that end.


2. The Screw in the BOTTOM of the Smooth Rails on the Keyboard Side under the machine are loose.


3. The Head is UN LEVEL.


Most likely 1.....


AL

[cestout]

I can understand not compressing because of dust, there by preventing the carve from being started; but this happens mid carve? However, blowing out the roller switch always fixes the problem. I just don't understand how it goes from compressed to uncompressed mid carve.

[henry1]

Sometimes I get check for stuck back roller, part way thru a carve. I thought that the rollers were either compressed or not. So what causes this, and is there a way to check it without aborting the carve to remove the board? It just happened again, enter to continue worked for one pass, so I stopped the carve, lifter the head and blew out the back roller switch. I restarted the carve and of course it matched up perfectly and is still going, but I lost over a half hour of carving time.
I had that problem not long ago , when I did a check on sensors was ok , then I got that problem when running . so what I did I change the the switchs out , now working fine,, it not a big deal to change them

[DickB]

I can understand not compressing because of dust, there by preventing the carve from being started; but this happens mid carve? However, blowing out the roller switch always fixes the problem. I just don't understand how it goes from compressed to uncompressed mid carve.
Could be dust in the switch itself. I know the close cover switch was not a sealed type; I had two fail then replaced with a sealed switch and no more issues. I don't know if the compression roller switches are sealed.

[Digitalwoodshop]

When you get the problem has the board come out from under a roller during the carve? It might be watching for the uncompressed as the board moves only under 1 roller. IF not.... then it could be electrical like posted above....

When the switch is un compressed it drops into the slot. When Compressed it pushes the switch OUT of the slot. So if it cannot drop in the slot because of sawdust build up then the computer does not see uncompressed when it expects it...

The Stuck Roller was ALSO how I found the Right Side smooth rail screw was loose letting the whole head lift. The 4 smooth rails that the machine slides up and down on... The Right keyboard one had loosened... Giving a Switch Change Indication and a message about the Stuck Switch AND Possible BOARD REMOVAL.....

I am just Guessing here.... I post all this because it may not be your problem but someone else may find this in a search someday.

And LAST but not least.... the Switch is powered by 5 Volts DC and a Momentary Short Circuit somewhere else could show up as a Roller Problem but usually a Open Cover first. In MY case.... Twice it was the 4 wires for the Board Sensor..... 5 Volts and Signal... One wire was pinched and Shorted on the Sharp Edge.

But Dust or Dirty Switch Contacts. I saw Electrical Contact Cleaner at Wal Mart the other day.... Un Plug Machine and spray switch with the fluid cleaner and let dry overnight. Careful as over spray may dis color plastic.

AL

[cestout]

Thanks all for your input. When I can sell something and get a few bucks, I will get a dust collector for this machine. I put on my ole (B) machine but not on the newer one(C) because I wanted to live in like it came from the factory for demonstrations, but I haven't done any in over a year and dust collecting really makes a difference in machine maintance. My wife even agrees on this, but now they cost more since he sell thru the company.

[ktjwilliams]

That heppened to me several times... The switches are accessed from the keypad side. Once I found that the switch itself was moving and thats how it happens mid carve. 1st off I make sure the switch is not moving, if it is I get it back into place and snug up the screws.. Next I look through from either the front or the back toward the middle of the machine so I can see the switch metal that rides on the side of the roller block. With a pry bar I gentle move the roller up and down and watch how the contact is working.. Then I make appropriate adjustments by bending the contact to a point that it's working perfectly.. I guess these contacts bend outta shape after a while.. By doing this I still have my original switches in my old A machine... Hope I was clear, I better at doing then I am at explaining ...

[Digitalwoodshop]

GOOD Stuff....

AL

[dltccf]

I got this on a carve the other day, I was using a sled that had a gap between the 3 1/2 inch end board and the piece that was being carved. When the roller was right in that gap I got the error.

dave