Is it just me or....

[El MoFo Grande]

...does the left chainstay on this Monark Silver King that is listed on ebay look bent? I'm guessing that it just could be the angle.

http://cgi.ebay.com/Monark-Silver-K...810?pt=LH_DefaultDomain_0&hash=item27b821b30a

 

[suparoospeedway]

id say bent.

 

[vibr8shun]

Yep, its squished in a bit. One thing about these old duralium (aluminium) frames is that if you try to bend it back, they tend to crack very easily (then you will have micro cracks on the outside and inside of the chain-stay). These are great looking frames, but not made of the same type of aluminium that they use today. It will be too expensive to have a metallurgist x-ray the frame for cracks.

...keep in mind that those were the days before tig welding, Cromoly steel, and lightweight aircraft aluminium...heavy steel was king :mrgreen:

 

[schwinnmesa]

Yeah, it's messed up.

 

[TheFlyingDingo]

COuldnt you check for cracks by running smoke, or fog or something through the frame, but seal off the obvious holes? (Bottom bracket, Headset, Seatpost)

 

[Unchained]

COuldnt you check for cracks by running smoke, or fog or something through the frame, but seal off the obvious holes? (Bottom bracket, Headset, Seatpost)

That's an idea. Clever thinkin' :wink:

I never tinker with aluminum, but that doesn't look that bad. I can't imagine that it is unfix-able, or fixable by extreme means at that. I think if you were really, really, really gentle and scrupulous, it could be fixed with delicate tweaking. Again, I don't know much about aluminum, but I think a good welder could fix it if it cracks.

My dad and I have an old aluminum Diamond T ten wheel tractor from the sixties that we play with periodically... we've had to weld a few things (some pretty big cracks in some rough places) and there hasn't been anything yet that his welder friend hasn't been able to fix for us.

 

[TheFlyingDingo]

For some reason, I am terrified by aluminum...Im going to assume its because I'm heavy, and if i land a big jump, Aluminum has the tendency to snap, rather than bend. Plus i usually dont see lifetime warrantys with aluminum

 

[outskirtscustoms]

I've stretched a few frames similar to that, I put a scissor jack between the stays and slowly crank it outward till it's tight and use my torch to heat the stays till they flex, crank a little more, heat, few more cranks of the jack, and repeat till it's about a 1/4 inch wider than it needs to be. Let it sit overnight with the jack in it to cool, loosen the jack and it normally springs back a 1/4 inch. Might work on old aluminum but no guarantees, it has worked on a smashed aluminum mongoose bike but it was newer. I have installed many a gear cluster hub on a cruiser frame like that. Biggest rule of thumb is TAKE YOUR TIME.

Hope this helps someone.

Also looks as though it is suffering from bent fork disorder.

 

[SCHWINNRAY69]

Looks bent :roll:

 

[axelrod]

COuldnt you check for cracks by running smoke, or fog or something through the frame, but seal off the obvious holes? (Bottom bracket, Headset, Seatpost)

You can use a dye penetrant inspection for the aluminum. You rub a dye on the area, wipe it off, then spray a developer on it and you will be able to see the cracks because the dye has settled in them. This and eddy current are pretty good ways to find cracks in aluminum that is not visible to the naked eye.

 

[M.Martian]

I've seen a woman's frame at a swap meet that had the seat stay snapped off. It was solid.

 

[vibr8shun]

I've seen a woman's frame at a swap meet that had the seat stay snapped off. It was solid.

Yep you are right, the seat stays and chain stays are solid...I use to own one. They are about 3/8 inch at its thickest and down to 3/16 inch at its thinest...if my memory serves me.