Weld? or Braze?

GoldenMotor.com

Greybeard

New Member
Feb 8, 2011
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Sequim WA
I'm putting a Honda GXH in a '53 Panther. Pretty tight in height but it'll work. The main issue I've had in mockup is the supplied motor mount I got with the EZM kit. It has an issue with the frame on the down tube. To build a mount is very simple. I need to install a 1" by 1.5" piece of rectangular tubing accross the gap, and then use a piece of angle on each side for the motor mount. The angle will be slotted on both sides to give me a fore and aft movement and on top slotted for the port/starboard movement of the motor.

So to the the question: would you weld or braze the rectangular tubing in place on the bike? My experiece with welding from "the day" is that welding might make the bike tubing more brittle and possibly crack from the vibration of the engine later on.

Thanks
Mike
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
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Ridin' inSane Diego, CA.
I would agree with GearNut on this as I am limited to brazing in this situation as I don't own a TIG welder. TIG weld or braze are your best options if you can't or don't want to bolt-on.

dnut
 

Greybeard

New Member
Feb 8, 2011
336
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Sequim WA
I'm limited to having someone else do it for me at this time. I went into a local welding shop, and the man insisted that TIG welding was best, and that brazing was akin to solder, or before they started using TIG systems.
In the years past, when I had an old buzzbox and a set of tanks, I frequentley used brazing to build split exhaust manifolds for inline 6 bangers. Never had one fail. However, I have had welds fail.
In the early '60s, my first good paying job was welding high pressure steam pipe, using a torch and a filler rod.
 

GearNut

Active Member
Aug 19, 2009
5,104
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San Diego, Kaliforgnia
Tig welding is perhaps the best way if.....if...... the welder really knows what they are doing. Brazing is perfectly acceptable too.
The problem arises when the base metal becomes brittle directly around the weld bead.
Tig welding done properly will nearly eliminate this problem.
Brazing done properly will not get the base metal hot enough to cause this problem.
 

Maxvision

New Member
Jun 13, 2009
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San Diego, CA
welding is alot stronger than brazing. But I braze more often than weld. I REALLY like using silver brazing rod with the blue flux coating that you "used" to be able to buy at any hardware store. Dunno why alot of Hdware stores quit selling them. The silver brazing rod is WAY stronger than brass rods. Damn near as strong as a weld.
 

Greybeard

New Member
Feb 8, 2011
336
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Sequim WA
I appreciate the responses guys. Haven't pulled the trigger on the crossbrace yet, but the engine is in the frame, sitting on angle irons with bolts between the angles clamping it to the frame..Have been considering spitting a piece of 1" inside diameter tubing, putting it around the frame under the angle, tigging it to the angle and just clamping it so the frame is left unmodefied. The problem is that I'd have no for and aft adjustment with it that way and would have to have it "right"
 

Ibedayank

New Member
Oct 29, 2011
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Columbia Tennessee
brazing/silver solder is still used to this day by highend frame builder because it does not get hot enough to weaken the THIN walled cromolly tubes they use