Author Topic: What type of metal tubing to replace a frame section?  (Read 3027 times)

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Offline SKOL

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What type of metal tubing to replace a frame section?
« on: August 17, 2016, 06:12:40 AM »
Hey everyone,

I have a spot in my frame that is in need of repair. I plan on purchasing round mild steel tubing that is 16 gauge and matches the outside diameter of the frame tubing. Weld in a slug in the frame, then weld the new piece into place. The location I'm working on is right here...



My question: what type of steel would be correct for a job like this? I looked around town and no one has 16 gauge round steel anywhere so I'm going to have to buy online I guess. I only need about a 3 inch piece. Some extra would be nice for practice runs to dial in my welder settings though.

Any help is appreciated.

Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #1 on: August 17, 2016, 06:13:43 AM »
Or if anyone has any left of scraps from a project they've done in the past and would be willing to sell it to me, I'd be more than happy to take it off your hands.  Also, if not, does anyone know OD off the top of their head? I'm at work and don't have dimensions in front of me but want to get a couple pieces purchased so I hopefully have something to do this weekend.
« Last Edit: August 17, 2016, 06:36:51 AM by DickBojangles »

Offline ekpent

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Re: What type of metal tubing to replace a frame section?
« Reply #2 on: August 17, 2016, 06:49:17 AM »
 Hopefully someone with a junk frame will donate you a hunk which would be perfect for your repair.

Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #3 on: August 17, 2016, 08:27:53 AM »
Thanks, looks like the closet brick and mortar Metal Supermarket is 2 hours north or 2 hours east hahaha. Of course.  Fortunately I have holes at the end of the frame rails to allow the gas pressure to be released. I will have the do the small hole trick to allow pressure to be released before I close those though for sure. Do you happen to know the OD? I'm going to put in a request online with them to get an idea of costs. I think it's 1.25 but don't know for sure. They have DOM with thicknesses of
1" or 1.25" x 0.065"
1" or 1.25" x 0.095"
1" or 1.25" x 0.188" Which is probably way too thick.


As for hot-rolled steel round tube the smallest they offer online is 1.5" in OD which I think is too big.

They also offer cold-rolled round tubing in grade "CREW" (whatever that is) in

1" or 1.25" x 0.065"
1" or 1.25" x 0.095"
1" or 1.25" x 0.118"
Also 1.125" x 0.065" or 0.120"

I don't know much about metal quality, and I don't have OD off hand. What do you think?

Offline slikwilli420

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Re: What type of metal tubing to replace a frame section?
« Reply #4 on: August 17, 2016, 08:54:55 AM »
I just picked up a 10 foot stick of 1.125" x 0.065" wall DOM that I will be using for some bracing on the frame for my race bike. How much do you need?
All you gotta do is do what you gotta do.

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Offline shifty5150

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Re: What type of metal tubing to replace a frame section?
« Reply #5 on: August 17, 2016, 09:06:30 AM »

They also offer cold-rolled round tubing in grade "CREW" (whatever that is)


C old
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Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #6 on: August 17, 2016, 09:07:51 AM »
I just picked up a 10 foot stick of 1.125" x 0.065" wall DOM that I will be using for some bracing on the frame for my race bike. How much do you need?

Realistically, 4 inches. But more would be nice to get a few test runs in. A foot? How much do you have to spare?

Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #7 on: August 17, 2016, 09:35:04 AM »
I just picked up a 10 foot stick of 1.125" x 0.065" wall DOM that I will be using for some bracing on the frame for my race bike. How much do you need?

Did you find it from a vendor in your town? Damn that would be nice here.

Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #8 on: August 17, 2016, 10:11:04 AM »

They also offer cold-rolled round tubing in grade "CREW" (whatever that is)


C old
R olled
E lectric
W elded

Thanks for that, I'm not gonna get it but its nice to know.

Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #9 on: August 17, 2016, 10:12:39 AM »
I found a vendor online that has decent pricing. I wanted your guys' opinion. The stock tubing is 0.063" or so... they offer 0.065" or 0.095". Do you guys think 0.095 would be too thick, or would actually be ideal?

They offer it in 1.125" OD which is probably what I'm going to go with unless that isn't the correct OD

Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #10 on: August 17, 2016, 10:18:58 AM »
0.065 is pretty dang hard to weld with unless you know what you're doing. Its so thin, so will blow it out before you get it to weld. I always opt for thicker when grafting sections back onto antique metal.

That's what I was thinking. I've welded a few tabs onto the frame but none of them are structural pieces. I'll probably go with 0.95" and get some cold rolled rod that matches the ID for my slug.

Offline slikwilli420

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Re: What type of metal tubing to replace a frame section?
« Reply #11 on: August 17, 2016, 10:20:46 AM »
I just picked up a 10 foot stick of 1.125" x 0.065" wall DOM that I will be using for some bracing on the frame for my race bike. How much do you need?

Realistically, 4 inches. But more would be nice to get a few test runs in. A foot? How much do you have to spare?

Alro steel has a retail store worth drops from other jobs as well as full pieces. It was only like $2.50 per foot. I could ship a 1 foot piece for like $8 all in.
All you gotta do is do what you gotta do.

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Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #12 on: August 17, 2016, 10:43:10 AM »
I just picked up a 10 foot stick of 1.125" x 0.065" wall DOM that I will be using for some bracing on the frame for my race bike. How much do you need?

Realistically, 4 inches. But more would be nice to get a few test runs in. A foot? How much do you have to spare?

Alro steel has a retail store worth drops from other jobs as well as full pieces. It was only like $2.50 per foot. I could ship a 1 foot piece for like $8 all in.

That's sweet, we don't have anything like that here, as far as I know. I would take you up on your offer, but I jumped the gun and bought it online from a vendor along with a few inches of solid round bar I'm going to use as a slug. I really appreciate how helpful you've offered to be

Offline slikwilli420

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Re: What type of metal tubing to replace a frame section?
« Reply #13 on: August 17, 2016, 03:40:02 PM »
No worries at all. Let us know how the repair goes.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
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Offline SKOL

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Re: What type of metal tubing to replace a frame section?
« Reply #14 on: August 17, 2016, 04:21:15 PM »
No worries at all. Let us know how the repair goes.

Will do, thanks

Offline rotortiller

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Re: What type of metal tubing to replace a frame section?
« Reply #15 on: August 18, 2016, 01:28:27 PM »
Chromemoly should do the trick.

Offline slikwilli420

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Re: What type of metal tubing to replace a frame section?
« Reply #16 on: August 18, 2016, 07:51:36 PM »
Chromemoly should do the trick.

Why bother? The strength only comes once it's normalized and it's more expensive. In this instance DOM will be far superior to the original tubing. Also can't MIG weld it.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline Smudgemo

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Re: What type of metal tubing to replace a frame section?
« Reply #17 on: August 18, 2016, 09:37:01 PM »
Any competent custom steel bicycle frame builder (that TIGs as opposed to brazing) ought to be able to TIG your repair.  The "thick" stuff for bicycle frames is .035" so blowing holes through .065" won't be an issue. 
-Ryan

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