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Steel frame repair Guru’s help
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ThrustyjustFree Member
After fettling with the Mk1 Stooge last, found a crack from the crimped area on the chain stay to clear the tyre to the underside . So approximately 1/3 of the tube. So, options are a/ emailed Andy at Stooge as read here about him helping with repairs, b/ Replace with a new frame c/ I can get silver rods and oxy acetylene at work and could clean out and re-braze or d/ friend has a tig and get him to tig it. e/ Send to Argos frames or similar STW recommended place
Issues
a/ Waiting on Andy response, no problem 🙂
b/ Is there any frames in the world to buy. Need 135mm qr rear end for my Phil Wood hubs as an issue
c/ Only issue is strength in the area after the repair and potential failure again
d/ As above really ,although if I had some chromoly steel, do a Bontrager gusset.
e/ May be more than the frame is worth in getting it done. If one side has failed then with the other in time, sooner than later ?Any other ideas or thoughts to get this rolling again 🙂
cynic-alFree MemberI have half an 853 frame you can have some of the chainstay of for a patch if that helps. If something like that fits, should be a solid cheap repair?
(I don’t think the stays are 853).
mick_rFull MemberSilver soldering crack on it’s own will be very weak. Tig will just crack again very quickly.
Silver soldered patch repairs usually work very well as it runs under the whole patch giving a lot of contact area. Brazing a bit stronger but harder to make it flow under and also putting more heat in.
I just had a clear out and binned some used 531 stays that would have made perfect patches. Al’s offer sounds good.
Or cut the whole of the rh stay front out and make a plate like Ragley etc use. I can get stuff laser cut if you can design something CAD (cardboard assisted design). Would be best to braze that in unless your tig guy is VERY good.
ThrustyjustFree MemberDo appreciate everyone’s offers and advice . Mick let me have your address to send the frame :). Its a shame for it to crack , its not been a good bike in the last year . Never had a failure in 30 years ( must try harder, oh hang on I must be now) and this is frame no3 , see my Cannondale warranty thread. Sods law just sold the new Cannondale frame that I could have used last Thursday……..
mick_rFull MemberAh I’d not twigged you were the Cannondale destroyer 🙂
Roughly where are you based?
ThrustyjustFree MemberBerkshire Mick, where the tracks are smooth and no climbs 🙂 Cannondale replacement frame that arrived was ‘completely different’ internally with the large hole in the seat tube , which was 16mm or so, now 5mm ish and larger diameter top tube and seat stays, says they knew it was rubbish and redesigned it in 2016.
Just got the wire brush onto the paint to strip back to metal to assess.
This frame is different in that its had a good life and accept that but just need to sort out my option to repair / buy a replacement / buy a second hand frame that swops stuff over.
dovebikerFull MemberI would suspect that’s too highly stressed an area to get a brazed repair to work effectively as it’s difficult to re-distribute the stresses and awkward shape to try and patch repair. I’d send a photo to some frame repairers, but would expect you’re looking at a replacement chainstay.
RustyNissanPrairieFull MemberGot your TIGmate some SIF Tig brazing rods – similar to Tig welding but with a lot lower heat. Get the smallest diameter they do and then flatten them further with a ball pein hammer.
I’d fill the crack with Tig braze then braze a patch over the top. Wouldn’t be pretty but would keep it going.
I would offer to do it but I am absolutely flat out.
ThrustyjustFree MemberThanks gents for you inputs. I suspect a repair for the better is a new chain stay + paint + decals wouldn’t be worth doing.
Tig welding the frame maybe short term and if I made a plate from posters above could be Ok for a while.
I noticed the upper picture has ‘nicks’ around the crack. Not used anything aggressive when cleaning off , just a wire wheel in a drill, so wonder if they are also additional stress marks? The chain ring side chain stay is mint. No visible damage or worming of the paint, which brought this to my attention.
Seen Triton have green Surly frames and forks for cheap money but no stock ( no surprise there)
I could get a Kona Unit new as a bike but the rear dropouts are bolt in, but suspect I could get QR ones. But then have a bike box of more parts. Damn well have enough bits but no frames as it is.
Anyone have a 29er Simple or similar ?damascusFree MemberI suspect a repair for the better is a new chain stay + paint + decals wouldn’t be worth doing.
Someone on here used that tape that sets like steel to fix a chainstay. If your not too bothered about the look it could be an option (if his hasn’t failed) certainly the cheapest.
Chain stays are usually wrapped in inner tube or neoprene anyway so you could do it in a way that wouldn’t show up too bad.
ClinkFull MemberAnyone have a 29er Simple or similar ?
oooooh, I’d love one of those! Searched for one for ages.
stFull MemberFor what it’s worth I’d say that is very repairable with a plate (by someone who is willing to spend a little time making it fit).
If it were my frame it’d be straight over to my Dad. He’s not a professional welder but very handy and is up for jobs like this.
On this basis there’s bound to be a frame builder who can sort it so all the best with getting it sorted.
mick_rFull MemberI could patch that foc or a donation to gnusmas fund. But other end of the country so would have to ship it. Best option is a new stay but I haven’t got any suitable to hand. Would probably drill, fill with braze and then silver patches over everything.
It actually sounds like you have the skills and equipment to do that yourself. It isn’t that hard.
I’ve done 25 years in a fatigue test lab as the day job. Any kind of tig repair breaks very quickly – welding on top of material that has already reached it’s fatigue life plus the new stress raiser of the fresh weld is a hiding to nothing.
cynic-alFree MemberSurely if a cheap repair like that is on offer it’s worth a go? New chainstay could be really tricky given the shape of it, the brace etc.? (And expensive).
Aren’t these frames pretty unique in terms of geometry…worth saving?
ThrustyjustFree MemberSpoken to my tig mate and he says he has some rods for brazing the frame. Wouldnt recommend silver rods as would fracture again. So might have to ‘go shopping’ near his house next weekend and assess.
Might need some frame tubing Al, but lets see what he says when he sees it in the flesh.
Would be good to save it as enjoy riding it.
Thanks for everyone’s input on this thread !mick_rFull MemberLooking at it properly on the laptop that is one hell of a dimple 🙂 Not very surprising it cracked (same as cynical-al’s Salsa).
TIG braze and then a silvered patch over the top would be good. It is all about running the spelter under the patch to get a big contact surface area and “glue” the patch on. That also leaves very minimal stress raiser from the patch. As he says, just a silver “weld” repair won’t last long.
I’ve got plenty of Columbus cro-mo offcuts 0.8mm wall in 22, 25.4 and 28.6mm diameter that would make C-shaped sleeve patches. PM me if needed and I’ll post some bits. Can also include a little Cycle Designs silver flux – paste that all over everything before soldering. Minimal heat, flux goes clear when it is ready, steel barely changes colour very faint / dull red. Too hot and you trash the flux. Cleans off with boiling water.
cynic-alFree MemberI think you are confusing me with molgrips – he’ll be flattered I’m sure 😂
jonestownFree Member@thrustyjust just a quick one, i’ve tried replying to your e-mail a number of times but my nessage keeps getting knocked back, i think you may have entered your e-mail address incorrectly. Drop me an e-mail – andrewj.stevenson@hotmail.co.uk. cheers, Andy
ThrustyjustFree MemberPhotos later of todays ‘plaster’ repairs and I am not talking about my thumb I shoved the hacksaw through…………..:)
I am happy anyway……….ThrustyjustFree MemberSo, before I start anything here, special thanks to Mick , who has gone beyond to help me with getting the bike back together again. I had a delivery this morning of a well packed and ‘Mick Kit’ tm , as it will be known of tubing , fluxes and welding rods. What I havent used, will be heading back to Mick for when we arrange a replacement chainstay to be fitted in the summer, geared bike months.
So, probably wrong to do, but the crack seemed to be at an angle, so I used a dremel to remove it. I also drilled a 1mm hole at the crack ends to prevent growth. I cleaned, cleaned and cleaned again, the frame , as thats the most important thing.
I then had a brand new mapp/oxygen welder from work, which was totally useless as the oxygen wouldnt stop hissing big time out the bottle to valve and when I removed the regulator the bottle kept hissing. So, binned that. I was ready to do this and all had was a mapp torch. So, out it came. I brazed up the slot in the frame really easily , even if it was minus something outside, as wanted to not damage my plastic floor in the garage with any flux and weld slag.
By the time I had filed and emery cleaned it was the same height as the frame chainstay.
Now, in this Mick Kit tm , was a selection of frame off cut tubing. More differing versions than chocolates in a box of Milk Tray. So, what to pick ? There was a piece of chainstay there and that was the chosen piece. I cut it in half and thats where the claret then smothered my dna everywhere as a hacksaw makes lighter work of thumbs than chromoly tubes. With the shape of the tubing, I ‘overlatched’ the underside ( if it was upright) and then bent and hammered to the contours of the chainstay. Mick had given me lots of materials, but with the brass rod making life easy, i decided to braze again with brass rather than silver.
Generally it has gone better than I was expecting . I have obviously cleaned up the plate with emery cloth and a wired wheel on a drill. I need to do a bit more tidying before I mask most of the frame and get some primer , top coat and lacquer to hopefully finish off.
This is temporary as long term I will get a new chainstay fitted and the frame and forks refinished. As Andy at Stooge says, only 100 of these were made , so worth keeping it as I do enjoy riding it.mick_rFull MemberTop work 🙂 that sif braze rod flows pretty well so should be good and solid.
That is definitely my magic time travelling parcel drop postbox! I sent some dropouts to someone else on here and they got to deepest Cornwall the next morning. The box near home is useless – posted some cable guides to a mate 10 miles away and they took over a week….
And thanks again for the Mint Sauce raffle tickets. STW at it’s best.
ThrustyjustFree MemberDefinitely a good parish to be in Mick. No laughing when it ends on you mat later this year:)
There is definite weld penetration as was worried about how much heat needed until I watched the video you said to watch gave me more confidence I wasnt doing to much. Worried me about the silver flux and heat and thought I would do in bronze as worked well for the crack including filling. Thought too much heat would make it run into the tube and be lost forever, but it didnt luckily.
Good luck of the raffle , either way its a good cause for all.
Thanks again Mick, will send photos later this weekend as discussed.mick_rFull MemberYeah brass tends to stay where you put it. If you have some silver rods then have a play with the scraps and silver flux. If you managed brass then you’ll find silver really satisfying when it suddenly flows and pulls towards the heat.
ThrustyjustFree MemberSituation Mick is that using the mapp torch doesnt give a precise enough flame to be able to move the silver. If I had the mapp oxy kit working, would give me a more pin point heat and now less paint to redo 🙂
ThrustyjustFree MemberIf people are interested then let me know, i’ll keep updating to the first ride ?. This morning I gave it 3 coats of rattle can primer. As the garage is a massive 4 deg , I kept the frame and paint in the house overnight. Bit more prep and clean then masked up. Wasnt planning on sharp edges, more feathering near the tape, but being so cold,the paint wasnt going to have that. So, I will have some wet flatting to do . But looking great. In fact the grey works well with the Stooge blue.
The house now stinks of paint and the garage doesnt. Weird that and currently not very popular.
hardtailonlyFull MemberIs that a crack in the downtube 🤣
And … looking back at the last picture of the chainstays before priming, looks like a crack in the opposite chainstay! 😳
svFree MemberThink that’s the edge of the clear protection tape and not a crack! Mk1s are lovely.
ThrustyjustFree MemberMuch to the eagle eyes finding additional cracks, that is frame protector. Phew……
So, without any drum rolls, its painted…….
Wrong colour mind but the local paintshop and me spent hours last summer trying to match. Its slightly darker but I am happy as it has a future. 2 coats of colour and a coat of lacquer. Its not gloss or matt but a satin, which I didnt have so it is now matt, but polishable.
Let it dry before rebuild……..
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