Backing rings

Date 05-17-2003 01:35

Hi John,
Sorry, I don't know of any pre-formed square backers.
What we do is to burn the inside shape out of 1" plate so the backer fits the tube and doesn't need splicing. Kind of a flattened, squared donut. Scrapping the center has been cheaper than forming and splicing flat bar. Just remember to check dimensions of the actual pieces to be spliced because, as you already know, they vary a bit.
Chet Guilford

By billvanderhoof (****)

Date 05-17-2003 05:11

If you have a break you could make channel that fits the inside of 1/2 the tube. Then saw it into pieces and use two for each joint. Might take just as long though.
Bill

By jwright650 (*****)

Date 05-19-2003 11:30

Bill,
Help me out again with your suggestion, I'm thick skulled and I am not sure I follow ya. You know for me you have to draw a picture!:)
Chet,
I had not thought of using 1" plate. Wonder if using the 1" plate for a template to bend the 1/4" thick flat bar around would be be any quicker? Then I would already have the basic shape for the different sizes and could fit it inside the tubing and perfect the fit with some heat and a ballpeen hammer for those pesky corners. I like to see those backers fit nice and tight without any gaps before I let them weld the joint up. I UT all those full pen splices in the shop and don't like to see the corners neglected. I'm just funny about what goes out our door.
John Wright

By CHGuilford (****)

Date 05-19-2003 13:28

John, do you have CNC burning equipment? If yes then just measure the inside radii for each corner to find the average and the inside dimensions. Have the rings programmed and burned and you should be golden; no splicing required. You can save the program for future work for that matter.

If you are looking for a something to hammer the rings to shape, then I would shape 2 halves from flat bar on a brake and splice them as Bill suggested. I haven't had much luck using mandrels. 2 splices on a bench is easier than beating the bar into submission and then still having 1 splice to do.

Another thought, sometimes you can use a piece from a smaller tube the fits inside. It doesn't work for all sizes though, cause the inside doesn't always match the outside of a smaller tube, but quite a few will match up.

Chet Guilford

By jwright650 (*****)

Date 05-19-2003 14:04

Our plant isn't as fortunate as our other plant. They might burn out some of those rings for me though. Great idea! I bet they haven't thought of that either.
John Wright

By jwright650 (*****)

Date 05-19-2003 14:41

Bill,
I "C" what you were trying to suggest now. I had a regular "channel" (C8x11.5 etc...) in my mind when I read your reply.
John Wright

By Tim Buyle (**)

Date 05-20-2003 06:32

look at www.robvon.com !!!

By jwright650 (*****)

Date 05-20-2003 11:24

Tim,
I checked out that site you mentioned. That is exactly what I was wondering about. I've seen em for Pipe, and wondered why not for Tubing. I'll get in touch with them and find out how much.$$$$
John Wright

By CHGuilford (****)

Date 05-20-2003 13:08

Tim, thanks for the tip. Even though we normally make our own "squings" it will be interesting to see the price difference.
CHGuilford

By jwright650 (*****)

Date 05-20-2003 13:52

CHG,
I submitted a request for a price quote, so we'll see...........
John Wright

By jwright650 (*****)

Date 05-20-2003 14:53

I talked with the mfg. and he gave me a quote for example....12 x 12 x 3/8 Squing is $5.44 each. I can't make them for that. He is looking into equipment to do larger section sizes, but 12" is as large as he can go right now.
John Wright

By CHGuilford (****)

Date 05-20-2003 16:01

John, thanks for the info. That's cheaper than we can make them.
Chet Guilford