I am a frame builder AMA

Looks pretty good to my untrained eye. Certainly better than anything I’ve pulled off with brass.

I think ima try get some of that flux and see if I get on any better with it.

Oxy Propane is how I started and is a cheapish way to get going. You can pick up a full kit for about £150 if you shop around (Weldequip etc). Propane is cheap and easy to get hold of.

Acetylene is great and (in my humble opinion) is much easier to build with. I
use both in my workshop to make the acetylene last longer. Joints with acetylene and braze ons and ends with the propane.

Joints with acetylene and braze ons and ends with the propane.

Ends as in track ends? Or as in to close the ends of tubes (seat stays etc)?

Are you using big tanks for your oxy propane setup or something more like,

Drop outs, stays etc all the little bits and bobs. You can use propane for everything but this is just how I do it.

I use reasonably big bottles but you can adjust this for your needs. I would recommend going for a proper kit.....some thing like this https://www.weldequip.com/oxy-propane-brazing.htm but you should probably do some research and decide what will work best for you.

Awesome, that looks like a good deal.

I need to figure out what the deal is with bottles.

Dumb question maybe but, when it's propane is it as easy as picking up a cylinder at the petrol station?

Found a place near me doing hobbyweld oxygen for £70+vat deposit and £24.99 a refill, seems pretty good but doesn't say the size. They only do oxygen, argon and an argon/co2/oxy mix.

Yep, just the standard orange/red bottle job. You should be able to get it from the hobbyweld stockists (they usually do!).

The hobbyweld oxygen is 9 litres if I remember correctly and not too spendy. The acetylene from them is pricey and Air Products are far cheaper......if you ever need it.

Cheers for the advice, I think I'm gonna go for that kit you linked to.

I had a look about and the only other thing I found was someone selling a sort of new old stock Clarke OA kit that could supposedly be used with propane on ebay. The price was good (half what Machine Mart want for the kit) but having done some more reading it doesn't seem quite as easy as just sticking a propane bottle on an acetylene regulator and torch so I'd probably rather just get the right thing to start with.

Also sort of picking up on the idea that propane is a bit of a safer option than acetylene for the home gamer so I'm reassured by that.

No problems bud. Good luck with it all and let me know how you get on.

Does anyone have any recommendations for a first tig machine, to learn on. I have tiged before but want to get into it properly. With the intention (eventually) to build a frame or 2. I did a course at the bicycle academy but OA isnt accessible atm

I was looking at this, https://www.r-techwelding.co.uk/tig-welder-240v-dc-160amp/.

or
https://www.r-techwelding.co.uk/r-tech-tig-mma-welder-dc-160a-digital-240v/#tab_review

not sure whether to go new or used, i dont really know where to look for reliable used. Ebay scares me.

Couple more daft newb questions...

1 - Right handed brazers, torch in right hand or do it like tig with the filler rod in your right hand?
2 - Sifbronze rods, I have piddly little thin ones, to lay down fat fillets I'm gonna want thicker rods right?

I got my oxy-propane kit set up today and have bashed out a few practice joints. It's so much easier to use than Mapp. Kicking myself for not making the jump sooner.

First I joined a couple bits of mild steel bar, then tried to break the joint but the bar bent instead, think that's a good sign.

Then I brazed some nuts to some strip steel and screwed bolts into 2 of them, strip deformed quite a lot before the joints eventually failed. I used to torque wrench and the joints were holding with 30nm on them.

Lastly I popped a couple bits of tubing together. Fit up was horrible but I was running out of daylight and then battery power in my work light. I did actually end up brazing in the dark so I'm happy enough with the results,

1 - Right handed brazers, torch in right hand or do it like tig with the filler rod in your right hand?

I'm right-handed and I have the torch in my right hand when brazing, but then when I'm TIGing I hold the rod in my left hand and the TIG torch in my right hand.

I’m sure I was taught to put the rod in my right hand when I was taught tig. Just tried it now and neither way feels especially ‘right’ though.

Think I’d been using the Mapp torch in my left hand recently but it’s such an unfocused heat source that it didn’t make much difference.

Cut up the tubes I joined yesterday, anyone got any feedback for me?

I seem to be getting a bit of a fillet inside the tube right? Albeit not very consistently.

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I also tried a bit of dent filling as geetingbthe filler rod to take to just a surface (as opposed to a joint) was something I’d never been able to do with silver.

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Hi framebuilding posse - would anyone have any suggestions re. a builder in london who would grind off a couple of mudguard eyelets off a titanium track frame for me? I’m obviously willing to pay someone for their trouble but as it’s such a small job I can’t imagine 99% of builders could be bothered with it. I would do it myself expect I will definitely cock it up and casually grind an entire seatstay off...

Titanium is hard as nails and horrible to work with. I've drilled a few for Di2 before and its a P.I.T.A!

I would recommend asking Geoff Roberts or Winston Vaz

Titanium is a bit soft in reality but I suppose it depends on your viewpoint

Lots of folks start on r tech don't believe it's all down to the machine...by any stretch

I get what you mean but compared to drilling a standard steel bike tube, it's a ball ache.

Cheers matey, will investigate!

Would you mind if I ask what set up you went for? And how much it cost?

This kit,

https://www.weldequip.com/oxy-propane-brazing.htm

Then spent about the same again on a 13kg Propane and a Hobbyweld Oxygen. Of course refilling them will be much cheaper.

I’ve also bought a pile of brazing rods - £20 or so, a sparky lighter doodah - £5, a tub of flux - £10, some shade 3 glasses coz the goggles the kit comes with are a bit crap - £10.

I also spent a couple hundred on practice tubes and lugs but that’s up to you...

If I got the train over to Glasgae, how much do you reckon I would have to pay you to pop a disc tab on the back of my crusty old MTB? Just been quoted £60 which is more than the frame really deserves...

Hmm, if I said half that but you have to bear in mind I’m still very much learning as I go?

Do you have the mount and any way to hold it in position?

When I put the mount on the back of my Hummus I just used a wheel and clamped the caliper and mount to the rotor, tacked it then removed the wheel. Could probably do similar for brazing but if you had it a bare hub and rotor might be better given that there’d be a bit more heat kicking around?

Have you spoken to Andy Armour and Colin Woof as they are over in Edinburgh.

No worries at all about you still learning, the frame is a POS so I'm not bothered if it's not quite as neat. I will be perfectly happy with something like your Hummus.

Do you have the mount and any way to hold it in position?

Currently I have nothing. I'm still exploring options... Andy Armour is the person who just quoted me £60. I'm not quite that emotionally attached to the frame and my V brakes are adaquate so can't quite justify that. I will look up Colin Woof though!