welder in London?

wildmoustache

i want to weld a metal bottle cage onto my 2nd bike ... no, i'm not nuts, I realise the bosses are for attaching cages ... the problem is that the threads are stripped ... for all four bosses. other than fitting a behind the saddle cage (not good in group riding), this is the only option i can think of.

my idea was that somebody could simply weld a metal cage directly onto the bosses that are in the frame and won't come out.

any ideas on where might do this ... ideally somewhere that has worked with bikes before.

Kléber

Why not put in some self-tapping thread inserts?

wildmoustache

Kléber wrote:

Why not put in some self-tapping thread inserts?

because i can't get the existing bosses out... assuming the self-tapping inserts need a hole to go into???

Gwhizz

Why not just drill and tap the frame yourself?
A couple of 5mm set-screws and shake proof washers ought to hold the cage in place.

wildmoustache

Gwhizz wrote:

Why not just drill and tap the frame yourself?
A couple of 5mm set-screws and shake proof washers ought to hold the cage in place.

thanks for the suggestion, but i would be too worried about wrecking the frame. iit's not that expensive a frame but would be annoying to trash and then have to dismantle and build up a new frame

maybe i'll bring it round to yours to get sorted?

Gwhizz

Anytime WildM,

Was just thinkin that if you go down the welding route this adds a lot of heat into the frame and however does the job would have to be careful not to warp the frame.

Gwhizz

however does the job would have to be careful not to warp the frame.

Sorry "whoever" :oops:

wildmoustache

who could i get to do the drilling then? would any of the decent bikeshops do it?

Kléber

wildmoustache wrote:

Kléber wrote:

Why not put in some self-tapping thread inserts?

because i can't get the existing bosses out... assuming the self-tapping inserts need a hole to go into???

Yes but if you have the bosses there already, you could put some spring tap threads in there.

Then there are cable ties too. Welding is going to be messy and you'd have to respray...

LangerDan

Most metal cages are alu or magnesium and it will be a bit tricky to try and weld those to a steel frame. Plus if you ever bend / buckle the cage in future you won't be able to change it. If you trust yourself to drill the mountings, but not tap them, you could always try using a Rivnut (essential an internally threaded pop-rivet) - thats whats used for the cage bosses on the Merckx alloy frame. I would have thought that some of the bigger bike shops / builders in London have a rivnut gun.

(The problem with a "welder" is that lot of them are used to sorting gates and brackets and bits of chassis rails. They amy not know that a bike frame is so thin and could well burn through the whole flipping thing)

Alternatively you could just bond the cage on with some epoxy.

Monty Dog

A local sheet metal fabricator may be able to help with the Rivnuts - drill out the boss to the required size, insert Rivnut, squeeze trigger and job done. Alternatively, you could look at getting a Helicoil fitted, which involves putting a helical steel insert into the hole, rather than a rivet. Don't even think about welding - bike frame tubes are pretty thin and apart from a skilled welder, you'll probably end up with a couple more holes. Bottle cages bolts use a 5mm standard metric thread. A final option is that Minoura make a bottle cage mounting brakes that uses a stainless stell band around your frame tube - it's fairly robust or a true bodger could use a couple of Jubilee clips.

JonEdwards

Just helicoil it. (spring tappy thing as mentioned above. It'll be a 10 minute job.

richa

Adding Water Bottle Cages to Bicycles without Braze-Ons:
http://www.nordicgroup.us/cageboss.htm

"Sure you could cobble something together using funky hose clamps (jubilee clips), tape, or by drilling holes and installing Rivnuts where you shouldn’t, but it looks tacky and unprofessional. Use one of these methods to do the job right."

Kléber

Failing that, for a touch of class, use gaffer tape.

richa

This looks like a good bet.

wildmoustache

thanks for the responses so far... the special cage attachments look a bit on the heavy and ugly side, but i will look at them more closely later (it is my second bike, but is still used for racing and some mountainous sportifs so has to be kept light and respectable in appearance ).

So drill and rivet might be my best option. I don't care much if these are the last cages fitted to the frame ... the object of this is to squeeze another year or two out of the frame.

LangerDan

wildmoustache wrote:

thanks for the responses so far... the special cage attachments look a bit on the heavy and ugly side, but i will look at them more closely later (it is my second bike, but is still used for racing and some mountainous sportifs so has to be kept light and respectable in appearance ).

So drill and rivet might be my best option. I don't care much if these are the last cages fitted to the frame ... the object of this is to squeeze another year or two out of the frame.[/quote]

If thats the case, perhaps you needn't even bother with the Rivnuts. Just attach the cage using standard pop-rivets. You won't have to drill out the thread. It might be worth including a split washer or similar to keep the poprivet under tension as they have a habit of creeping and rattling.