5th CW, Traction Belt Sandpaper offset measuring problem

[zeke]

Can you believe this, I can't get a machine that works out of the gate. This time the first time I loaded a board, it had a measuring problem. Called LHR, the tech came back and asked me if one of the belts was offset. Sure enough it was.

Here's the second part of my problem, he couldn't tell me why this happened, just that I got a new older version and the newer machines have fewer problems. I asked if there was some adjustment and all he could do was send me the instructions to replace the belt, call back on Monday to get belts as needed. In my mind, I can put another belt on, but may end up with the same problem. Anyone know what causes a belt to offset? Is there an adjustment? By the way, the belt drifted toward the keypad side, if that matters.

What do you usually use to secure the plastic gear box back, plain old silicone?

[liquidguitars]

Or, you can cut the belt 1/2" from the end at the pinch..

LG

[zeke]

Or, you can cut the belt 1/2" from the end at the pinch..

LG

How do we know the belt even a 1/2" shorter in width won't drift with the same result? If I knew what was causing this, I could probably fix it. Maybe this is one even the seasoned veterans don't know the answer to since LHR didn't know.

[pkunk]

Cutting the part off that is curled under with a razor knife is a sometimes temporary fix. It is a factor of belt tracking, usually the fault of the belt itself. I did have an out of align(no fix but replacement) carrier on my first machine, but that is rare. Cut it, call for a replacement, & you should be good to go.

[zeke]

Cutting the part off that is curled under with a razor knife is a sometimes temporary fix. It is a factor of belt tracking, usually the fault of the belt itself. I did have an out of align(no fix but replacement) carrier on my first machine, but that is rare. Cut it, call for a replacement, & you should be good to go.

OK, I'll give it a try. Do you have a technique for cutting the belts? I saw one thread using scissors. Also, do you use plain old silicone to seal the gear box cover?

[pkunk]

Don't take it apart. Just use a razor knife & trim off the bad part of the belt. You can rotate the belt (with power off) by pushing with your hands.

[zeke]

Don't take it apart. Just use a razor knife & trim off the bad part of the belt. You can rotate the belt (with power off) by pushing with your hands.

I love shortcuts! Work smarter, not harder, you saved me a fair amount of work, I was ready to dive in and follow the replacement belt procedure and cutting it that way. Thanks for saving me time and thanks for being a VET!!! Your great pkunk.......

[zeke]

I started to cut the belt, however the side that was infringing on the guide plate was a bit loose as compared to the other side of the same belt and the other traction belt. I'm going to replace the belt. I also measured the roller pressure and it is right at 100. I thought 100 might be too high from some of the posts I viewed and that 75-85 is optimum, is this correct? Do you think high roller pressure could have caused the belt to slide to one side and how do you lower the roller pressure?

[oldjoe]

There was a post awhile back not sure by who about traction belts being narrower on one end. This is what is causing your wondering belt. Also saw somewhere where they are working a new tougher belt.

[Kenm810]

Hi Zeke,

I know these post are the opposite of what you were asking,
about to much pressure from the rollers.
But I remembered someone posting about removing some spacers or removing some of the tension on the handle spring.
To stop the project board from slipping with the belt or digging into the traction belts I found these in a search Key Word " Spacer or Spacers" This info is only meant to give you some place to look.

Increasing Pressure from rollers. (http://www.carvewright.com/forum/showthread.php?t=2160&highlight=spacers)
QC? Broken out of the box (http://www.carvewright.com/forum/showthread.php?t=3771&highlight=spacers)

[Dave Boland]

hey Zeke. Had same problem couple months ago. If your rollers are not parralell with "Y"
track it will drift the sandpaper. Place a wide board in machine and slowly crank head down, notice where it just touches. It should touch evenly across the board. . If sanpaper is drifting towards keypad then the roller is probably touching on that side 1st.
Lay machine on it's side (muffler side) remove 12 screws and bottom. Behind the wiring harness is a screw with washer that holds the connecting rod between conical gears.
Remove screw and washer. Drop rod slightly so it is no longer mating drive gear.
Set machine back up to upright position and slide it so that you can reach under machine
(need abkout 6 inches of over hang) Hold rod up with one hand and crank back down on board till barely touching again. Drop rod and turn it by hand clockwise until rollers touch
evenly on width of board. Push rod back up to mate with front gear and secure in place with screw and washer. Should solve your problem. Sounds hard but only takes about 15 minutes.
Gear box cover snaps into two slots that are hard to see, but they are there.
Dave

[Dave Boland]

Zeke, high pressure usually means clutch plates are dry. Try lubricating with Lithium. Pressure should go down to acceptable. Dave

[zeke]

Zeke, high pressure usually means clutch plates are dry. Try lubricating with Lithium. Pressure should go down to acceptable. Dave

I took the crank handle off, slid some grease behind I believe it was part# 147, the crank torque plate (not sure if this is correct, limited viewing space, see attached). This is the washer where the center hole is shaped like the crank handle part that is recessed into the machine. I then cranked the machine several times, measured pressure, still around 100-105. Tried a bit more grease, same result. Removed one part# 152, clutch spacer washer, dropped down to 94-95, removed the second washer got down to 91 and holding, can't get down to 75-80 lbs. Based on where I put the grease, is this how you do it and what is the part# for the clutch plates?

[zeke]

Reporting on the end-result to my drifting and roller pressure problems. First Dave your suggestion to ensure the rollers were parralell with "Y" was a good exercise as it was off slightly, but apparently wasn't my root cause. However that exercise also uncovered and helped with another issue that I had where I couldn't get the roller pressure below 91. After making the adjustments to the connecting rod between conical gears and putting the machine back together the roller pressure went from 91 to 66. I then added a spacer to the crank handle moved up to 71, added another and sitting at 76lbs.

The root cause of my drifting problem turned out to be one of the drive conveyor belts was frozen on one side and slightly compressed, see pics attached, one of the rods between the rollers appears bent. I received new drive conveyors belts from LHR and installed them this week and the situation is better. I also made some simple belt replacement clips out of a clothes hanger that worked well as pins, I attached a pic of those as well.