Gerber Sprint 2b plotter cutting Problems

[kevinmac]

Need some help with the following problems:

Replaced the Theta belt on my 2b. Problem-belt seems a little too lose.

Letters cut ok, but seems that their is some minut overlap cutting. This

can easily seen on an uppercase A. The triangle on the inside (top of

triangle) is not a clean cut. Not so much a problem with other areas of the

letter. It's overlapping a very very small amount. Never had this problem

before the Theta belt replacement. Any thoughts on fixing this would be

appreciated.

Kevin
SignWriteHere

 

[Fred Weiss]

The adjustment of the theta belt tension is done, as I recall, by loosening the idler gear and tensioning it while retightening it. You should be going ofr about 1/4 to 1/2 inches of relatively easy movement when you squeeze the two sides of the belt. It isn't a seriously critical adjustment ... as long as the belt stays on and no jumping of the gears on the belt take place, it is okay.

Of far greater importance is the rehoming of the blade position at startup. this position is lost when the theta belt loses enough teeth to jump position or when it is replaced. To reset the home position:

• Remove the plotter front end cover.
• Rotate the chrome shaft that runs through the tool head and follow the motion back to a collar clamp near the theta rotation motor.
• Loosen the collar clamp enough for the shaft to rotate without turning the motor.
• Put a piece of vinyl in the plotter and turn it on.
• Rotate the lifter shaft manually to bring the blade down and into contact with the vinyl.
• Slew the vinyl to the left. The dragging of the blade on the vinyl will cause it to rotate into the correct home position.
• Without moving anything, retighten the collar clamp.

Your tangential blade is now correctly positioned for clean cutting.

If you still have overcutting, check the blade depth setting and what degree blade you are using. On that machine, a 30 degree blade is recommended. A small amount of overcutting is considered normal.

The use of a "theta washer" is highly recommended as well. This is a teflon washer that fits on the bladeholder and reduces friction on the lifting fork in the tool head as the bladeholder rotates. They are available through any Gerber distributor for a couple of bucks if you don't have one.

 

[kevinmac]

Not sure where the lifter shaft is.
How does it apply the needed pressure
to make contact w/the vinyl?
Please explain.
Thanks!

 

[Fred Weiss]

It's the black shaft right at the point you feed the vinyl in on the right. Rotating it will lift or lower the bladeholder in the tool head. No pressure other than the weight of the bladeholder is required for the homing adjustment.

 

[kevinmac]

I'll give it a try tomorrow.
I was using the 2b manual
on locating the homing position.
Your way seems to make more sense.
Do I have to worry about readjusting the lifter shaft after all said and done?

 

[Fred Weiss]

No. It homes each time the machine is turned on as does the tool head.

 

[kevinmac]

Not working.

Everytime I try to drag (slew to the left) the blade or knife holder raises. Now what?

Thanks.

 

[kevinmac]

By the way, my 2b is a sprint 2b that I've been running thru or with the link module card (if that matters)

kevin

 

[Fred Weiss]

Not working.

Everytime I try to drag (slew to the left) the blade or knife holder raises. Now what?

Thanks.

It shouldn't lift if you did what I attempted to explain. But you can always just pull the vinyl manually. The trick is that the blade will take the path of least resistance if its in contact with the vinyl and that is the correct home position.