Jantaras

Hello all,

I bought this 70's RIH-Sport. Unfortunately one dropout got bent/crushed during delivery, the spacing was about 7 mm instead of about 10mm. I bent it back. Even before bending back I noticed some cracks at least at the surface of dropout, mosly near the adjusting screw hole. I have discussed with the seller, he says he can refund if want to return the frame.

I would like to keep the frame if the steel is not cracked. When I think of it, why would steel crack from this quite minor bend (3mm)? So I hope it is just the chrome that cracked, even one of the cracks looks quite bad...

There are no professional framebuilders nearby nor LBS as I live in a quite remote area.

So I want to inspect the dropout. What would be the best way to do it? I thought to poke with the sharp knife first trying to flake some chrome off and then sandpaper or dremel. Any other suggestions, maybe some chemicals to strip the dropout to bare metal(available in Europe shops)?

What are your thoughts about this damage?

Thanks!

TenGrainBread 

First of all, I have seen a lot of crushed dropouts like this being bent back with no problem. So you didn't do anything wrong by bending it back. Steel is ductile and generally rear dropouts are made from a slightly softer, ductile alloy than the harder alloy steels used for frame tubes.

The cracks just could be scoring or scratches in the chrome. What I would do is take a small strip of sandpaper and sand around that "crack" on the outside of the dropout to see how deep it goes. You could also use a dremel with sandpaper drum attachment but you need a very light touch if doing it this way.

It is annoying that you have to remove a little chrome to check this, but if it turns out the "crack" is just a shallow scratch, you can touch up the spot with chrome paint.

Moe Zhoost

Great pictures. I agree with the above post that those marks are likely to be only in the plating. Could have been prevented had the seller properly blocked the dropouts and forkends. Did you check to see if the axle spacing is still correct?

nesteel 

Sorry, if they start at the dropout adjuster screw holes, they're likely full cracks. You might get lucky, but I doubt it. While the material is generally malleable, it just cant survive as it's too thin at the tapped holes. Those tapped holes create excellent stress risers. Just add the stress from being bent due to incompetent packing, and you have disaster. Just my observation/opinion.
Send it back, let the seller eat it.

Glennr134

If you know of an automotive machine shop around you , they can do a process called magna fluxing. That will tell you 100 percent if its indeed cracked.

xiaoman1 

Agree with both comments, I lost a rear drop and it cracked in the same place that yours shows "lines" Magnaflux is the best way to check.
I would check it before doing a lot of riding, losing a drop in that area will cause the RD and the chain to do damage not only to the bike but could also result in the rider taking a serious fall...best to be sure.
Ben

Bad Lag

Tap it. You know, make it sing. Make it ping.

Compare the bent one to the unbent one on the other side (comparative anatomy).

My guess - the cracks are only in the chrome and the underlying steel is fine. The chrome is brittle and could not take the strain.

merziac

I vote for cracked, time for a new DO.

Jantaras

Thanks you all for input, really appreciated!

I can clearly see them and my fingernail can kinda "grab" the edge, at least to my eye they look like real cracks, not just scuffing. I hope the cracks in the inner curve could be just chrome. The nastiest of them all is the one at the adjusting screw hole, one can even see light shining through in image from the side, looks like it is more than just superficial

Googled a bit and I can't find any magnafluxers here locally, maybe they don't advertise.... I think I'll try sanding first.

BTW, would Magnafluxing show how deep is the crack? Because I am sure there is cracking, just is it confined to the chrome superficially, or goes to the steel.
The other dropout looks good, no such cracking. Did not check rear spacing yet, but I think it was reinforced with something while shipping, I think it should be ok.

Glennr134

Look up automotive machine shops , almost all of them do that service. If memory servers me correct, the deeper the crack, the more testing material collects on it.

jiangshi

Cut your losses. The dropout is done.

Jantaras

Hello again.

An update. Finally got time to inspect it again. After carefully sanding and then dremeling I think the cracks are buffed out Did not need to remove a lot of material. I can't notice any suspiciuos for cracks anymore.
So, I think this frame could be built and ridden hard, what do you think?

bark_eater 

Now you need to do the bell test. Sit and tap both drop outs with various little mallets and try and desiper the differences in tone.

One thing does occur, if the adjustment screw threads are deformed internaly, don't force one in.

I mangled a stamped drop out on one bike. I heated it to dull red before straitening it out and heated it again after. Hopefully that will reduce the work hardening.

noobinsf 

Is there a line at the 7-o'clock position in relation to the dropout screw hole in your second photo? Not sure if I'm right, and even if so, whether it's a concern...

Compared to what you showed before, though, this is much less worrisome.

unworthy1

I think you lucked out, congrats! Only a loss of some chrome plating but that was cracked so bound to chip off at some point. Now if you still have the slot to re-open to an even gap should you first thread in a screw before DO bending (that's what my gut check says would be safer but what do frame experts advise?)

Pcampeau

Nice dropout. Can we see the rest of the frame now?

Jantaras

Thanks for responses.
Didn't have the time to inspect the dropout with mallets yet. Took some images of the frame with some random wheels, no headset yet.

It's a RIH-Sport Super Course, Reynolds 531 tubes, Campagnolo dropouts. Based on serial numbet it was made by Fongers in 1967. Rear spacing is 120 mm. Feel free to add any other information

easyupbug 

Finland has "testing labs", I used them when working with Outokumpu. Weld shops also have dye penetrants for checking critical welds. Your dropout looks good, and I suspect the likelihood of a failure is low but consequence of a failure can be very serious. Magnaflux (and other dye penetrants) shows the depth of a crack by the depth of the color. Here in the states we can buy the penetrant, developer and prep in a kit for less than a $100 and they work well.