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Discussion Starter · #1 ·
I just a found a crack in the frame of a Jamis Diablo (just above the pin that holds in the rear shock.) I really don't know how this would of happened as after i rode it for a few hours doing small jumps.....by small i mean getting maybe 2 foot of air and landing downhill ahah so it could be classed as a tiny jump. But anyways i doubt it can be fixed but will this crack make the frame significantly weaker?

(ill get some pics up tomorrow)
 

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Bikepedia lists the frame material as 7005. To me that means it could be an easy weld repair provided you use 5183 or 5356 filler.

Warranty on frame is out?
 

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Discussion Starter · #6 ·
Yea the frame is made with 7005 aluminum, if i were to use 5183 or 5356 filler on the crack would the frame need to go through the process of heat treatment etc?

The warranty is long gone unfortunately, i brought it a while ago second hand and it is a 2007 model.
 

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DarkLands said:
Yea the frame is made with 7005 aluminum, if i were to use 5183 or 5356 filler on the crack would the frame need to go through the process of heat treatment etc?

The warranty is long gone unfortunately, i brought it a while ago second hand and it is a 2007 model.
No heat treat is necessary. Your frame is already T-6 hardness. 7005 is a slow acting precipitation hardening and softening alloy, as opposed to 6061 which is a fast acting precipitation hardening and softening alloy. In other words, your frame will take hours instead of minutes to soften. The weld should only take a couple minutes .

When your frame was manufactured, the weld procedure called out for prehardened components, then welded, and then finally stress relief. For economical reasons, the stress relief was achieved during the powdercoat process, which bakes the powder at 350 to 400 degrees F.. Then it is many weeks before any load is put on the frame by a rider, allowing some more stress dissipation.

Your frame, being such a small repair should be just fine, provided you do not ride the bike for at least a week for some of the stresses to shake out(dissipate).

Easton's Tech sheet on 7000 series alum fabrication will help explain some more.
http://www.eastoncycling.com/bike/wp-content/uploads/2010/04/fab_instructions-7005_6061.pdf
 

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Discussion Starter · #8 ·
shovelon said:
No heat treat is necessary. Your frame is already T-6 hardness. 7005 is a slow acting precipitation hardening and softening alloy, as opposed to 6061 which is a fast acting precipitation hardening and softening alloy. In other words, your frame will take hours instead of minutes to soften. The weld should only take a couple minutes .

When your frame was manufactured, the weld procedure called out for prehardened components, then welded, and then finally stress relief. For economical reasons, the stress relief was achieved during the powdercoat process, which bakes the powder at 350 to 400 degrees F.. Then it is many weeks before any load is put on the frame by a rider, allowing some more stress dissipation.

Your frame, being such a small repair should be just fine, provided you do not ride the bike for at least a week for some of the stresses to shake out(dissipate).

Easton's Tech sheet on 7000 series alum fabrication will help explain some more.
http://www.eastoncycling.com/bike/wp-content/uploads/2010/04/fab_instructions-7005_6061.pdf
Thanks for the information it is greatly appreciated and will be put to good use :cool:
I just have to find a welder who is skilled enough to do it right.
Then no riding it for a week! :eekster:
 
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