[reflux]

Hi,

I'm having a disk tab added to my steel hardtail. It's a 00 Dean Private with 853 main tubes and 725 (I think) stays. With this info, can you tell me if I'll need to heat treat the frame after the tab is welded on? Thanks for your help, and let me know if you need more info.

Andrew

 

[Wumpus]

I didn't know that they heat treated steel frames. 853 and 725 are both heat treated tubes. The big thing about 853 is that the tubes increase in strength after welding/heating.*




*According to some people this greatest advantage comes form getting a lugged 853 frame as opposed to TIG welding as the heat zone is much greater.

 

[MrCookie]

Tig welding shouldn't affect your frame in a bad way if it is done correctly.
I would also recommend that if you do add disc tabs to a frame that was not designed for them, that you run a brace between the seat stay and the chain stay, so that the seat stay doesn't collapse under the torque that gets focused on that thin/thin walled tubing.

 

[reflux]

Tig welding shouldn't affect your frame in a bad way if it is done correctly.
I would also recommend that if you do add disc tabs to a frame that was not designed for them, that you run a brace between the seat stay and the chain stay, so that the seat stay doesn't collapse under the torque that gets focused on that thin/thin walled tubing.

yep.

Chumba is doing the welding and their specialty is aluminum. Common sense would've been to have the work done by a builder familiar with steel, but Chuma is local and came highly recommended by a friend.

Thanks for the help!

 

[Changleen]

If your stays are 725 you shouldn't have much problems. In an ideal world you would re-heat treat, but it really probably isn't worth it for that type of modification unless you are Mr. Super Anal. You're better off just adding a re-enforcing strut as suggested already.

Secondly, unless your heat treatment is done to Reynolds standards, (i.e. By Reynolds) I wouldn't hold out a high confidence of getting a great job done on it anyway, unless it was by a specialist frame builder. Instead of ending up with just a slightly weaker weld affected area, you could end up with a slightly weaker entire frame.