Relief For Channel Letter Backs

[Northern Sign Co]

Hello all, this is my first post and I thank you in advance for any advice you can offer. I've been given the responsibility of running our CNC router due to the previous person leaving the company. My question is, what is the typical amount of relief to take off of channel letter backs to ensure a good fit for the faces once the backs are wrapped? I hope I'm explaining this well enough. Thanks again for any advice.

 

[Bernard G NYC]

Hello all, this is my first post and I thank you in advance for any advice you can offer. I've been given the responsibility of running our CNC router due to the previous person leaving the company. My question is, what is the typical amount of relief to take off of channel letter backs to ensure a good fit for the faces once the backs are wrapped? I hope I'm explaining this well enough. Thanks again for any advice.

 

[GaSouthpaw]

It kind of depends on the thickness of the material being used for the returns, but my "usual" setup was the faces were cut actual size. For the backers, I took the faces and inlined them . 075" so the overall size was .15" smaller. This almost always worked just fine, unless the fabricator was sloppy.
I'd suggest, though, that you ask the person making the letters what they prefer. The may not need much play, or they might need more. It's almost always best to check.