FINNEY1973
Senior Retro Guru
mdvineng":q178mslz said:
Interesting - how does that work though when the dropout & hanger is one solid piece? Would take a lot of precise work to adapt.
Vitus Repair
- Thread starter kingbling
- Start date
Interesting - how does that work though when the dropout & hanger is one solid piece? Would take a lot of precise work to adapt.
Yeah it would need a bit of fettling :facepalm: but not impossible I could probably accomplish it with hand tools grinder and dremel I have an idea of drilling and pinning the broken part which was given to me with the frame I can't show you any pic's as the misus doesn't know I've got it 
stefthehat
Retro Guru
I work in composites,once a dropout is found,and old one removed{heatgun on droput,glue softens,drop out pulled oout with molegrips},replacement is fairly straight forward, old epoxy needs to be filed and chiseled out, both inside of tube and 'male' ends of dropout need to be abraded,now the more important part : a good 2 part epoxy, not a tube of generic araldite from the corner shop,marine repair suppliers or pro carbody shops provide such things, I can look on a data safety sheet to see the chemical names of the two parts of epoxy at work next week, a good brand is Plexus but not cheap
Robbied196
Senior Retro Guru
I looked at doing the very same thing a couple of years ago and came to the conclusion the frame was scrap :facepalm: Getting well bonded joints apart is extremely difficult. I tried heat which didn't work and you have to be wary of too much force damaging the tubes or other joints.
There was very a specialist process to bonding these frames. Originally it was done by Bador S A who developed heat activated epoxy bonding for the aerospace industry and supplied Airbus. They bonded under laboratory style conditions with exceptional attention to joint cleaning prior to bonding. There were some factory joint failures on hard ridden bikes but they are comparatively rare. The broken jointed frames that turn up for sale are often on frames that have been rebonded and the same joint has failed again. Personally, I wouldn't trust a rebonded frame.
The problem with the dropout is they have quite long spigots, around 40/45mm. Assuming you can break the existing dropout joints and remove the broken dropout, you'd then need to push the seat stay and chainstay apart to refit a new dropout. The angles of the triangle will be wrong to fit the replacement dropout.
There was very a specialist process to bonding these frames. Originally it was done by Bador S A who developed heat activated epoxy bonding for the aerospace industry and supplied Airbus. They bonded under laboratory style conditions with exceptional attention to joint cleaning prior to bonding. There were some factory joint failures on hard ridden bikes but they are comparatively rare. The broken jointed frames that turn up for sale are often on frames that have been rebonded and the same joint has failed again. Personally, I wouldn't trust a rebonded frame.
The problem with the dropout is they have quite long spigots, around 40/45mm. Assuming you can break the existing dropout joints and remove the broken dropout, you'd then need to push the seat stay and chainstay apart to refit a new dropout. The angles of the triangle will be wrong to fit the replacement dropout.
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stefthehat
Retro Guru
Most modern epoxies such as Plexus blow the old ones out of the water,basically what was once 'industry only' is now available to the public, 'laboratory conditions' are easily replicated at home with correct process' and materials{solvents etc}and self disipline,would love to see what dropout was going to be used as a replacement, having the dropout snapped through the mech hole is a bummer what I've done in the past is thread in a steel bolt off a defunct mech and heat that for a good few minutes with the heat gun on high setting not aiming it at frame, the bolt obv conducts the heat and that travels into the alloy dropout and thence the epoxy
Blackbike
Retro Guru
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