Cincinnati Press Brake FormMaster 2

[jmartin931]

Having promblems with consistancy of forms on a Cincinnati form master 2 press brake. Cincinnati service people can not find the problem, was wondering if anyone else has had any troubleshooting expirience in this area. 175ton press with heavy duty backgage making 6 bends in 1/4" gal. steel. Backgage is accurate, and sometimes finished part is. Then again sometimes the part is off .030". It's not the operator, doesn't make a difference who runs it. Any help is apprieciated.

Thanks

 

[griffengm]

jmartin931,
What kind of shape is your tooling in?
How well secured is the die?

Griffy

 

[jmartin931]

The dies are in descent shape. The upper die is held secure by the die clamp. However the lower die is segmented for bend clearence porpuses and must remain loose. The alighnment between the two seems acceptable. Today one of the maintenance men found that if he physically moved the backgage without changing the encoder position(have used dial indicator to set exact encoder position in the past), we could get a tolerable part. Still not perfect though. Seems like a possible program error in the bend allowance, although the design engineer assures us this is not the case. We have been fighting this issue for right at a year now, and spent nearly $8K on Cincinnati service tecs to no avail. Any thoughts are still apprieciated.

Thanks!

 

[griffengm]

JM,
When you say "off .030" do you mean individual bends are off by that much or that a feature affected by 6 bends is off that much (cumulative)?

Griffy

 

[jmartin931]

cumulative

 

[tarzan56007]

is there any chance that the steel itself could have inconsistant measurements, thickness or length.

 

[BillPSU]

Your process is not very well defined. Is this an air- bending set of dies or a bottoming set of dies? If air-bending, is the bottom die opening 8 times the material thickness? Your upper punch is is 1.5-2 times the material thickness? The material is it hot finished or cold finished? What is the width of the part being formed? What is the tolerance on the thickness of material? Describe what the .030 means, is it the overall width of the part, the parallelism or a flatness?