Welding.

flickerx

So, I was thinking of doing a 10-week Fas welding course this summer, just to broaden my life skills. Priced a few of them in Finglas and Cabra, which would suit me better, they work out at 250 - 350 euros.

To be honest though, I know next to nothing about it, being an intellectual/academic type fixed gear snob and all that.
What type of welding should I be going for - if I'm keen to possibly apply it in the future to chopping up and sticking back together steel bike frames?

There's a few different types of welding courses on offer - gas, arc, etc.
None of them mean anything to me.

E@gle.

do u mean welding for cycling purposes??

BeardyGit

Gas welding and brazing is what you're after.....

Ghost Rider

Having welding skills would pretty much make you the Pope of bike mechanics.

flickerx wrote: »

So, I was thinking of doing a 10-week Fas welding course this summer, just to broaden my life skills. Priced a few of them in Finglas and Cabra, which would suit me better, they work out at 250 - 350 euros.

To be honest though, I know next to nothing about it, being an intellectual/academic type fixed gear snob and all that.
What type of welding should I be going for - if I'm keen to possibly apply it in the future to chopping up and sticking back together steel bike frames?

There's a few different types of welding courses on offer - gas, arc, etc.
None of them mean anything to me.

E@gle.

maybe you would get a better response here

http://www.boards.ie/vbulletin/forumdisplay.php?f=116

fish-head

TIG welding is the most usual process for bikes, isn't it?

Design_Dude

For automated lines yea, but they cost a lot o money. Go for Mig, they give a cleaner weld than arc and arent too expensive. You can also weld alluminium with mig, whiuch could be a help.

roadmanmad

Do the course, but you will probable find that you would have to charge more for the service than most are prepared to pay for. Price the welding kit and calculate your return on investment.

One other element is that poor welding is the primary source of crack initiation, a normal precursor to metal failure.

Do not walk yourself into doing a fix where you are being asked to stand over or even certify the repair. Just remember you need advanced technologies to determine the presence of a crack that you cannot see.

As I said, do the course, you will be in a better position to assess the idea after completing it.

kona

****e welds advance corrosion too.

i was thinking of doin one myself, e250 isnt much tbh!

flickerx

Well, I dont know what TIG or MIG welding is - I'll google them know in a minute to find out! There's a course in Ballyfermot - not exactly ideal to get to for me, but it covers the following:

# INDUCTION
# CAREER PLANNING AND JOB SEEKING SKILLS
# IN-COMPANY
# MANUAL METAL ARC WELDING
# M.I.G. WELDING
# MOUNTING OF ABRASIVE WHEELS
# T.I.G. WELDING
# READING BASIC TECHNICAL DRAWINGS
# OXY-ACETYLENE CUTTING
# SAFEPASS
# INDUCTION EVENING COURSE
# MACHINE TOOLS (WELDING)

Its 350 euro for 5 weeks, with 2 x 3-hour sessions per week, I think I would prefer to get it done in a short space of time rather than drag it out over ten weeks. Its a bit pricey, that's just under a weeks wages for me, but I'm interested and could definitely see myself sticking it out, rather than dropping it like a less practical evening course.

I'm not really looking to do anything commercial, I wouldnt trust anything I'd put together myself enough to sell on to someone else. Its more just for the pleasure of creating or mashing something together with my hands (and some hardcore tools too, of course.). I'd like to have a go maybe at some point at making one of those ridiculous tall bikes.

But as I said, its also just to learn a new life skill, which may be applicable to bikes in the future. Even something just like welding a braze on for a brake cable might be useful to do.

flickerx

Ghost Rider wrote: »

Having welding skills would pretty much make you the Pope of bike mechanics.

Ah here jaysus come on now, I've yet to master putting in a headset.

Once I've got that down, you will all kneel and praise me.

kona

Ghost Rider wrote: »

Having welding skills would pretty much make you the Pope of bike mechanics.

mechanics deals with moving parts, id hope the welding isnt that bad:D

but ye very handy skill to have, it takes immense practise tho!

on another note, isnt brazing the way they join the mounts to the bike, ie pour hot metal on it and the heat fuses the parts together
cheaper bikes have it done on the joins too??

welding is slightly different although i think mig is along the lines of brazing?

niceonetom

kona wrote: »

on another note, isnt brazing the way they join the mounts to the bike, ie pour hot metal on it and the heat fuses the parts together
cheaper bikes have it done on the joins too??

not quite how brazing works. lugged steel frames are brazed together with brass and it's not a cheap way of doing things, though it is easier than welding for hand manufacture. the tube slides inside the lug and brass is melted in between the two fusing the metals together in a sandwich. the steel doesn't melt at all. if flickerx is planning on building his own frames this would most likely be the way to go as you can still buy steel tube-sets and lugs from manufacturers (don't ask me where though) and cut things to your own geometry before brazing. would not be cheap though.

there's also 'fillet brazing' which i think using brazing to fill and smooth acetylene welds giving a sexy smoothness to the joins. experts only though.

i'd say do the course, it's always nice to be able to do sh't like that.

Gavin

Welding ! You some sort of pansy ? I'm looking at taking up knitting ! Get some merino wool and then I can construct my very own high quality wicking cycle clothing. baselayers, jerseys, gloves, socks etc, the sky's the limit !

The Queen of Bicycle Mechanics !

Design_Dude

indeed u are!

unionman

Verb wrote: »

Welding ! You some sort of pansy ? I'm looking at taking up knitting ! Get some merino wool and then I can construct my very own high quality wicking cycle clothing. baselayers, jerseys, gloves, socks etc, the sky's the limit !

The Queen of Bicycle Mechanics !

I get that. Best I can do is bake a bicycle shaped cake.

Good on you flickerx, it sounds like an interesting course. Having seen your handiwork in person, I'm sure you'd find the course enjoyable.

I'm still getting over the shame of displaying my general ignorance by referring to your ferrari stem as a headset.

Doh!:o

311

I've done most types of welding as part of my training ,it can be expensive to have the equipment at hand.

If I was you I'd take a course in whatever is economical to use ,rather than best for cycling.

Arc welding is probably the cheapest form of welding and you can apply it very easily to many things.

flickerx

unionman wrote: »

Good on you flickerx, it sounds like an interesting course. Having seen your handiwork in person, I'm sure you'd find the course enjoyable.

I'm still getting over the shame of displaying my general ignorance by referring to your ferrari stem as a headset.

Nearly finished that other bike now. Sorry I havent been in touch with you to pick up the rubber housing cover, its been a bit of a mental week. I might get it off you next Monday or Wednesday morning, will text you.

I wouldnt be too embarrassed about the stem/headset mixup, I'm sure I made much more stupid mistakes in front of bike shop staff when I started to advance into more serious bike repair and construction, vaguely remember a couple of years back referring to the cranks as the bottom bracket. I mean, like, oh my god...

I think I'm going to do the 5 week gas welding course, and then maybe later in the summer do an arc welding course. I've been reading up on it a bit.

unionman

flickerx wrote: »

I might get it off you next Monday or Wednesday morning, will text you.

No probs.

flickerx

flickerx wrote: »

I think I'm going to do the 5 week gas welding course

Starting this tonight so will let you all know how it goes.

rob1891

If you need any steel frames to work on in the future let me know. I have two that are broke and lying around. One old Kona Cindercone that has cracked at the drop out. I guess the repair would involve finding a replacement dropout and welding it in. The other is a lugged Tommasini road bike that cracked at a previous repair point on the down tube near the head tube ... no idea how it was repaired in the first place or how to go about repairing it now, does not look like the whole downtube was replaced before.

I'd guess neither are economic to repair, and I've already moved on emotionally :-) so you can have both gratis if you think you'll work on them.

Rob

flickerx

Hey, thanks, thats really sound of you. I will definitely take you up on that offer - but not for three weeks or so, tonight was just getting the hang of using a smaller nozzle with the oxy-acetylene torch, and making the little liquid metal pools in a straight line on the metal plates. Then later on we started adding in some filler material, I think it was steel but it was copped coated to stop it rusting. It took time to get the hang of merging the two together, but I really enjoyed it. Some of the other lads in the class have done other types of welding before, and went straight into slightly more advanced stuff like pipe welding.

Of course the brains of the operation here was wearing a t-shirt, so when I started doing the welding with the wire and getting sparks everywhere, my left arm got a few little dots of heat...

But yeah hopefully I'll be able to have a go at fixing them towards the latter end of the course. I'll PM you soon. Nice one!

311

flickerx wrote: »

Of course the brains of the operation here was wearing a t-shirt, so when I started doing the welding with the wire and getting sparks everywhere, my left arm got a few little dots of heat...

Wait until it gets down the back of your neck:D

Fair play to you for taking it up ,it can be really enoyable.:)

flickerx

Hmm. It was getting a bit more difficult last night, with some more complicated joins. And I'm definitely the person with the least experience in the class so its a bit disheartening when you see the lad next to you working the magic on his pipe like it was second nature. But there's a good atmosphere in the class, one guy came over to help me and give me advice on getting the flame right, and using the filler rod..

Definitely going to do some other welding class later in the summer time.

kenmc

flickerx wrote: »

you see the lad next to you working the magic on his pipe like it was second nature.

He sounds like a right wanker altogether
sorry - couldn't resist!!!!

Capt'n Midnight

Verb wrote: »

Welding ! You some sort of pansy ? I'm looking at taking up knitting ! Get some merino wool and then I can construct my very own high quality wicking cycle clothing. baselayers, jerseys, gloves, socks etc, the sky's the limit !

The Queen of Bicycle Mechanics !

Don't you mean wire wool ?

you can't weld cheap bike frames , the metal may be to thin /weak

expensive steel frames may need heat treatment after the weld, isn't this why brazing is used ?

alloy frames DO need heat treatment after a weld

have a look at bike frame building courses to see what they need

flickerx

Tried to make something approaching a bike frame on the 6th session of the class this evening, bearing in mind I'd never done any sort of metal welding before in my life I was reasonably happy with the progress so far. It took time to hand cut the tubes with decent angles at the joins, for when I was adding in the filler and the flux so the two pieces of metal were reasonably flush with each other. I didnt really get as far as I wanted, only got half of the chain & seat stays (or what approximated to them) done. My brazing technique is still pretty bad, but slowly improving... you've got to crawl before you can walk I guess. It was only copper piping as well, the steel stuff is way too thick to construct a bike frame with, but in the next session I might be able to get some lighter steel pipes.

Way too dangerous to even consider using it in real life... dont expect to see it on eBay any time soon. Only place suitable for it at the end of the night:

kona

you should try to make up a jig for a frame, it would allow you to get good angles!, and perfect the frame.

the course looks deadly how much is it??


aluminium is heat treated as a metal anyways to align the molecules to strengthen it.

flickerx

kona wrote: »

the course looks deadly how much is it??

300 euro, for 10 sessions, two evenings a week

kona

flickerx wrote: »

300 euro, for 10 sessions, two evenings a week

deadly, do they show you mig welding and all the different techniques?

show you steel and alloy welding??

im defo going to do this when i et back from canada, where is it on? is it a fas course?

flickerx

kona wrote: »

deadly, do they show you mig welding and all the different techniques?

show you steel and alloy welding??

im defo going to do this when i et back from canada, where is it on? is it a fas course?

Yeah its a FAS course, its in Poppintree.
They start you off on the very basic techniques, getting the flame right, using the filler and flux etc, on different types of welds. I've only been using oxy-acetylene gas so far, I think thats all the room we are in is kitted out for, but next week we can have a quick look at arc welding if we want (there is another FAS course in arc welding in the same place, I think).
We've also used the gas cutting tool but that thing scares the living daylights out of me. Too much hot metal sparking and flying everywhere, and the cuts it makes are very unwieldy.

Dont know about mig and tig welding, but I'll ask tomorrow night about them.

flickerx

Here's the road bike frame that rob1891 gave me



As you can see there was a large crack in the down tube:



I think I mentioned it earlier in this thread that when I brought it into the shop, they wouldnt take out the b/b for me on safety grounds. They were afraid that if I put a new b/b in, that I might actually use the frame to build a bike, and they thought doing that would be lethal...

So I ploughed on anyway and got ready to prep the frame for a rebuild. But as mentioned on the bottom bracket thread I just couldnt get the b/b out. I still wanted to have a go at welding the down tube back together anyway, so I jammed the frame in a vice, and tried to line up the crack as best I could. You can see as well that I burned all the paint off with the oxy acetylene torch and then cleaned the surface down with steel wool and cloths to try to make sure the surfaces were clean for a weld.



So generously using a brazing rod and a load of flux, I stuck it back together. Bearing in mind my welding technique was still in its infancy, I managed to tack it down and then build up a mass around where the crack was. It looks pretty bad but the weld is fairly solid - I put a lot of pressure on the frame once the weld had cooled to check if it was reasonably solid. My girlfriend who is a sculptor said that I could easily file down the weld to make it smoother, without necessarily damaging the bond where the crack was - but I didnt do this, because the frame wasnt completely aligned properly when I welded it - the frame kept on popping out of the vice and it was driving me insane, so once I had it steady I just tacked it down and got to work. It wasnt perfect.

Anyway here's the results. Looks a bit like someone's got some gold coloured chewing gum and stuck the frame back together! If anyone feels like taking it and having a go at removing the b/b let me know, its yours to collect at any time of day or night (its outside my house at the moment). Someone out there might even want it for an art project. I painted it a small bit but it looked awful, but I cant find the photo of that though.

Thanks to rob1891 for the frame to have a practise on anyway (and sorry for the delay in putting these pix up, been mad busy with finishing off the self build fixies lately), it was much appreciated.

rob1891

Hey great job, has anyone said to you that it is unsafe other than the bike shop?

I think the traditional fix is to insert a tightly fitting tube inside the frame across the crack and then braze it in like you would a lug (at least that was a fix done on the seat tube of a bike of my dad's many years ago ... it cracked at the same spot in the end). I would wonder if the fillet style braze you have is strong enough by itself at that point on the bike ... but I know nothing about frame building so I only have questions :-)

Would you chance riding it yourself? I hear the best way to test head tube strenght is to stick the wheels either side of a ^ shaped thing and jump up and down on the thing :-)