PhilDAS learns to glue (mostly) metal

Much like @sensom though many thousands of miles away from him in a workshop (kitchen) which leaves a lot to be desired, I too am beginning to build a bicycle. I feel some sort of connection there, spiritual, sexual, I don't know.

But enough about him. Before running balls first into my frame and messing it up, I thought I'd get a little practise.
I picked up this Coppi copy from @mdpye a few weeks ago which has been in a tumble and is a bit cracked and bent. I was going to repair the crack as it is only small and at the top of the seat stay top eye but with the creased top and down tubes I figured its not really worth the effort unless I replace the tubes which I don't plan to do right now.
So I brutalised it
sorry

This gave me some material for practise brazing.
I don't have a work surface or table so I'm using the kitchen table which as you can see, is pretty tatty anyway and its a rented flat so not mine. With this in mind though, I don't have anywhere to put a proper vice so I bought this little clamp on variable angle Stanley number which whilst small, is actually pretty sweet, clamps tight, is pretty fucking rigid considering.
I also don't have any tube blocks so I'm holding tubes straight in it whilst not clamped particularly tight. It works ok, moves a little bit when rigorous filing but I'd rather that than crushing a tube.
Anyway, hand filed two sections of tube together

Whacked out the flames and burnt the paint off

After checking the mitre is still tight I smothered it all up in flux (not enough as I later learned) and cracked on with the fire

Handsome devil

End result is that where there once was two tubes, there is now one T shape piece. They are indeed stuck together and I am moderately happy with it.
Lessons learnt are:
Use more Flux. By the time I flipped the joint over to do the back, there was very little flux on the joint and when the brass melted it just blobbed on rather than pooling and flowing so the back is rougher.
Use more heat. I was scared of over heating it and as a consequence, I was hovering around the temperature of the brass melting so it was barely doing so and I was getting quite frustrated. I think I need to use a slightly bigger flame, more oxygen, get the whole area a bit hotter.

Advice welcome

Wear jawbreakers instead of regular sunglasses

The hand filing mitres is quite therapeutic I found. I did the seat tube at the bottom. Whilst this doesn't actually fit up against another tube, I wanted it to follow the inner shape of the BB shell so filed that to shape

Here's the frame mocked up roughly. I did also cut the seat tube to length and tested the lug on the top but didn't "shoot" that.

Finally I started on the top tube. Measured all my butts... and filed my TT/HT mitre. Pretty happy with the fit up.

That's it for now. I will be working on it some evenings and into next weekend

I also hit myself in the thumb while filing which lead to Shining-like scenes

But then if you don't slice your thumb open while filing, were you even trying?

Looking good! After my limited experience in lug brazing i would def advice using silver on first lugs and some practice lugs and tubes from ceeway for brass brazing. Cut up and see how filled they are..

Looks good.
Is there some craaaazy safety law about doing this in a residential flat?

Highly likely that there is. So don't tell anyone

Sage advice but that sounds way too sensible. I'm nervous but I think I'm just going to go for it, silver is expensive.

Haha word. Looks fun!

All i can recommend is to open some doors and windows when melting stuff ;)

Practice lugs are like 2.50 GBP pp and tubes like 4-6 GBP. I would knock 3-4 practices first just to figure out how to draw the filler... silver is much easier to work with and wouldnt cost you more then 30-40 GBP for the frame. Would be a shame to ruin the nice tubes/lugs or have the frame disintegrate while riding.. gl!

A totally fair use for it, I approve! Keep the photos coming

Do you cut the pipe first to the rough miter shape? Or straight to filing?

If you don't want to waste time, cut a rough fishmouth with a hacksaw, then file.

What tubing are you testing on there? Seems to be a lot of blackening, so maybe a more concentrated flame needed by feeding a bit oxygen.

I thought about it, but new files make light work of thin tubing. It takes less than a couple of minutes to get it roughly the right shape then it’s just a case of finding the high spots.

It’s just whatever that red frame is made from. Columbus SL seat tube if the decal is to be believed.
I’ll try a concentrated approach. I’m going to do a few more tests and I think even get some practise lugs as suggested above

https://youtu.be/qjAhgd9K-8o

I think he said he burned the paint off a donor frame which might explain it

you are totally crazy, great job! I like this thread!

Looking good, not afraid to leap right in!

What size tip are you using on the torch on the above photos? The central cone of the flame seems to be larger than what I'm using (with a N°3).

I'm much more comfortable with the cutting, filing, things I can take my time over but there's not really much choice than to leap right in with the torch and brazing. I am moderately to highly terrified of it but I'm hoping it gets easier with practise.
After doing that first joint my initial thoughts were: if you are considering a custom frame but after seeing this thread, think "hey I can just do it myself at home with a little practise", don't. Pay a framebuilder.
YMMV
Its a #3 as well dude

don't. Pay a framebuilder.

oh ok then

After doing that first joint my initial thoughts were: if you are considering a custom frame but after seeing this thread, think "hey I can just do it myself at home with a little practise", don't. Pay a framebuilder.

Thanks for sparing me a lot of frustration.

You can afford it anyway.

I'm loving seeing all the other threads of people tinkering in this sort of thing at the moment though. I have a hundred ideas for bike I want to build, this shit gets me really excited but I just hope I get better ha

I am only half joking.

I am a designer and deal with 'I have photoshop I can design this myself for £5' mob everyday.

tinkering

This is what its all about.