kraftwerk 

I have here a rather nice looking Erickson frame with S&S couplers (!) and a nice sized dent in the top tube.. cool thing is the dent is smooth, paint didn't even crack. The frame seems well-aligned despite the ding. I have about 5 frames needing repair, this one will hopefully be an easy fix, by me... at least one the others will seek professional help, some will just "be") To fix the ding I have the ability to get inside the tube, since as I mentioned, the frame is equipped with S&S couplers. I am now wondering if i cant just 'send' some kind of expanding device inside the frame whilst compressing the outside tube with a hose clamp something like a "SHAW_PLUG" *. But the shaw plug would have to be the perfect size (and maybe NOT made of rubber?) a regular two piece expansion anchor might work as well ...It will also have to be remotely operated since th' ding and the frame 'opening are at opposite ends of the tube.. Is this one of my frames who should visit an expert? It is really a very nice-quality- built-thing.





* https://www.grainger.com/product/14M...!471564520201!

JohnDThompson 

Something like the expander wedge on a quill stem might be able to do it. 1" diameter top tube? If the dent is close enough to the coupler opening for the wedge to reach the dent, a quill stem might be sufficient. If it's further away, you'd likely have to fabricate your own tool.

Cynikal 

I've seen someone fix a dent in a headtube with a quill stem as the expander. I don't know how much space a S&S allows into the tube but , in theory, if you can get inside you could push out a dent.

unterhausen

don't s&s have a flange that would keep something full diameter from going in there? Been a while since I had my travel bike apart

I made a tool the size of a 27.2 seat tube that has a wedge like on a quill stem. Wouldn't be hard to make one for 1"

Andrew R Stewart 

The few S&S that I have in hand (and brazed up) have an access hole about .7 of the tube's OD (this derived from a 1.125" lugless set and about what I remember from the lugged versions i have done). Sp the plug's expansion would need to be about 150% (likely more due to spring back). Additionally the plug would ideally want to be slightly convex or bulged at it's center to focus the pressure at the dent's center and produce lessening expanding force towards the dent's ends. A ball shaped plug could result in localized out dents if not careful and a flat plug would result in a shallow dent still present. I don't think any of the stem style expander plugs would work here. I'll add that the plug would also need to have a long flay "half" so to not bulge out the undented portion of the area. Andy

bulgie 

I'm not optimistic about your chances of getting an expander in there. The regular method of squeezing it in metal (not wood) tube blocks from the outside may be worth trying, if you don't mind losing the paint. But unless it's bad, I'd just leave it alone. Any Erickson is a precious thing -- and they aren't making any more of them! One with S&S couplers even more so. Don't risk making it worse.

Mark B in Seattle

kraftwerk 

Thanks for all the responses. You guys are great and give me a lot to think about.

trainman999

Is there a vent hole at the end of the tube? Could you mesure the opening in the S&S coupler, go to the craft store get a wooden ball or barrel that close to the Id of the coupler or you can sand slightly to fit? Drill a hole through the ball, thread a mountain bike brake cable through ball each way.. Thread the cable through the coupler and out through the vent hole pull the ball doun past the dent. Get a piese of copper tubing as close to the Id of the coupler as you can. Cut two slots 90 degrees fron eash other like you are making a tool to remove a headset cup. spread the ends, thread brake cable ,insert into the tube past the dent. pull the ball into the copper tube. pull the copper tube with the ball in it past the dent pushing it out. Don't know if you can make this work, but I have a Dent in a down tube I am going to pull the ball up the tube to try ond push it out. Good luck with your dent

fietsbob

Lets see if the search function gets "snarling Iron"


there we go.. bang down on the outside part with a hammer, and the inside end bangs up.

Last ride 76 

Can you please explain as clearly as possible, what that person used, and what steps they took to fix the dent in the head tube. I have a bicycle that received two small dents in the head tube, from insufficient packaging when it came over from Europe... Thanks!!!
*(Columbus) Head tubes are made of pretty sturdy stuff...

Doug Fattic 

Is your dent on the end of the head tube or somewhere in between? If it is on the end, canes can be squeezed together to help round the end of the head tube again. If it is in the middle, than an expander of some kind might work. Adding to these suggestions for expanding tools are lug vises. Usually the base diameter of the expandable part of the lug vise is 1". And then various sizes of sleeves are slipped over the vise to fit whatever inside ø is required. This might involve turing a sleeve on a lathe to get just the right fit.

unterhausen

It would be nice to have a tool to expando a head tube that has been dropped. I did that to a frame sitting in the shop and it's amazing how bad the dent was. I wonder if an exhaust pipe expander can be used

Andrew R Stewart 

Why are we talking about a head tube dent? "I have here a rather nice looking Erickson frame with S&S couplers (!) and a nice sized dent in the top tube" This is the first sentence in this thread... A headtube dent is quite a different thing then a toptube one. Andy

unterhausen

This is why​​​​​​
I'll post a picture of my dent removing quill tool later. I suppose the same type tool could be made for a head tube.

Last ride 76 

True. I'll separate. Hijack unintended...

Andrew R Stewart 

No need. My "complaint" was my fault for missing the added HT dent question post.

Eric- thanks for getting me straight. Andy