JacobLee 

Hey Framebuilders,

I found this Steelman frame in the scrap pile at the dump today, and I’m wondering if it’s wall art, or could it be repaired? Also, we’re used to seeing the gusset on the downtube, but this one cracked at the toptube; what causes that? I guess the downtube gusset protects against the stresses of aggressive riding, but maybe this frame was ridden into a wall?

Any info would be enlightening.

Thanks!

unterhausen

The reason it was at the dump is that there is no way to economically repair that.

guy153

Frame is toast. But you could replace the TT which might be a fun project. Why did it fail there? Probably also just from hard use (and maybe it would have failed at the DT if it hadn't been for the gusset). It looks more like fatigue than brick wall to me because there are no ripples, it's just cracked without apparently deforming first. Steel isn't brittle like that.

CliffordK

Does that have a horizontal top tube,or a sloping top tube?

I'm not sure about competitive cyclocross, but if it was a road bike the based on the seat post, I'd choose a frame 1" or 2" taller.

I wonder if the short head tube caused stress to the area.

unterhausen

It could have started because of a front hit, but more likely it had a defect in the weld due to the lack of real estate on the head tube. I would have thought it would start between the tubes, but it appears to have started at the top.

You might find someone to repair it, it shouldn't be cheap. Some people give away their labor though.

JacobLee 

Thanks, everyone. I’m pretty sure this is from the horizontal top tube era, when cross frames still had dt shifter bosses. They also usually had a matching steel fork, so that’s why a front impact seemed likely. Maybe someone rode it with a different fork until the frame crack appeared. Who knows. It’s way too small for me, so I doubt I’ll go to great lengths to fix it. At least if I put it back in the scrap pile, it won’t have a perfectly smooth UN-71 bb and a bunch of other cool parts left on it!

unterhausen

There is an advantage to level top tubes with cx bikes because they are easier to shoulder. Dual water bottle cages argue against it being a pure CX bike though.

pwyg

A top tube replacement is as basic as it gets. The biggest issue is you do not want to tig it again as tig characteristics are even poorer on the second weld. It will have to be a fillet repair which will take away the hardening aspect of tig welding. I would check the frame for internal corrosion to ensure it has not checked out on the inside due to lack of ventilation which is common with many builders.

headwind15

Cutting the top tube out is really easy if you use a 4.5" angle grinder with a 1/16" disc cutting wheel, making small cuts just behind the tig weld all the way around.

guy153

The HT and the top of the ST are pretty thick though and you're replacing the TT. So it would probably be all right.

GrayJay

The frame does have a lot of neat features and craftsmanship that could justify saving it. A repair could be made in which you cut the existing broken TT several inches forward from the seat cluster, fashion the remains of the existing TT stub into a lug shape to mimic the similar lug layer at top of the seattube. The existing (broken) TT looks a bit oversize so you could replace it with a slightly smaller (1"?) tube that would slip into the newly formed lug and then get brazed together. Benefit of this approach would be less disruption, re-welding of the frame at the seat cluster area. The miter at front end at the head tube (where the break was) could be fillet brazed (after cutting & grinding away all of the old broken TT) or else fabricate another similar bi-laminate lug at front to match the back of the TT.

JacobLee 

Wow, lots of cool ideas. I’ll probably try to pass this frame along to someone who might actually be able to execute the repair! If anyone around Portland, Or, is interested, let me know.

duanedr 

In practice this would be hard. The ID of existing tube as a lug won't likely match the OD of a new tube with gaps suitable for brazing. It wouldn't be a hard fix really to cut the tube out and fillet braze a new one in with a bi-lam treatment on the HT to add some strength back. This would be a bit tricky due to the short HT but, if silver brazed and use fillet pro for the fillet, I think it could work. And I'm a fan of Steelman so I would say it's worthwhile for someone who could do the repair themselves.

CliffordK

What if one just cleaned it up and rewelded. Grinding down the original weld some (V-grind the crack if possible). Especially grind a V in the gusset.

It may not bring the frame back to 100%. I wouldn't do competitive cyclocross on it. However, it should be usable for typical city/commuter riding, and certainly could extend the life of the frame for some time.

Personally I have troubles getting a good weld in a deep V between tubes, and that could be a weak spot, although the gussets should help.

On the right side, the crack does deviate from the head tube, but still should be weldable,and still should be within the double butting if the tubes are double butted.

unterhausen

Sure, just get the stick welder out

JohnDThompson 

I suspect economical repair is not possible unless you're willing and able to do the work yourself.

Andrew R Stewart 

I've seen plenty of welded repairs over the years. As much as I am not a fan of welded joining I have to say most of the repairs were still "working" when I have seen them.

My repair would involve partial TT replacement. I have a lathe so can turn an internal sleeve. Or an external one.

The first thing to do is to strip off the paint from the HT and a few inches of BOTH the TT and DT. Then look really well for other issues before going forward. Andy

guy153

It can be rewelded fine IMO. But what you would do is cut out the whole TT and sand the HT and ST ends back to smooth metal. No grooves or anything, just get rid of the entire original tube and the welds. Since both those tubes are quite thick (HT probably 1.3mm, that ST lug probably more) there's plenty of good metal to weld to. Then just mitre a new tube and TIG weld it in and it will look like new.

You can see Brodie did this with some CS:


The BB shell is also thick enough to just grind it back and reweld onto it. In fact with the exception of where the ST joins the ST all the joints on a bike frame are thin to thick and the thick end will stand rewelding.

guy153

Well at least then you won't have any difficult dilemmas about whether to save the frame or not... After five minutes of going at it with the stick it won't even be wall-art any more.

unterhausen

I think I see evidence that the head tube has cracked. At some point you just have to cut your losses. Or find someone to replace the whole front triangle. The previous owner decided it wasn't worth saving, that's a pretty good data point for me.

The OP is a self answering question in my way of thinking. Either you know it can be saved because you can do it yourself, or it's probably too expensive. Although like I said up-thread, there are people that do repairs for cheaper than the same work on a new frame. Which always has bothered me.

Nessism

If that frame were mine I'd cut off the top tube and dress it back in similar fashion to that show in the Brodie video. Look for cracks in the head tube as unterhausen suspects after the metal is clean. If it looks okay, then the light is green to replace the tube. I think the frame alignment should be checked and adjusted before mitering the new tube. After that though, it's a fairly simple matter to install a new tube. Steelman frames are cool so to me it would be a worthily project.