OMO - welding thin metal - advice please

[Nobbylad]

The Doris has broken one of her favourite lampshades in the living room. It's one of three and you can't get them, or anything like them anywhere on the planet (or so I'm reliably told :rolleyes:).

So I'm looking for a way of welding the arms or similar. They're very thin metal and I can't think of any way of fixing them other than welding them, but that seems a bit extreme.

Any advice/ideas gratefully received!

[flymo]

piccy?

[maviczap]

solder them?

less extreme than welding

I'd successfully soldered a broken fishing rod line guide before, I just heated the joint up by holding the soldering iron near the joint until it was hot enough to melt the solder.

Once the solder melted, I took the iron off & the solder set

The line guide was made out of thin wire

[DJ123]

Using a low power Arc welder should do the trick. Is there a local blacksmith/metal work shop that could have a look and advise as to what they recommend?

[Bibio]

braze with silver solder.

if its really thin don't even think about welding it unless you have a very very good tig or oxy torch.

[Specialone]

braze with silver solder.

if its really thin don't even think about welding it unless you have a very very good tig or oxy torch.

+1, a welder will blow that to pieces, unless a mig on low power and tiny blobs joined together, this takes a lot of time and skill.

Silver solder is much lower temp, or even braze with brazing rods, providing it won't ruin the finish of the item.

[TicklinJock]

The parts might have been "spot welded" together.

[markc123]

If you are still stuck next month, I can lay my hands on some silver solder and an iron with which to use it. Won't be back in your neck of the wood until then though.

[Nobbylad]

Thanks all. Off to Google silver soldering.

[andrewsmith]

Silver soldering should be fine. You'll need map gas and a Rothenberger torch.
It's a very fine and strong weld, which is used on air conditioning piping. When I say strong, the systems are strength tested at 32 bar and vac tested to less than 1 Tor

sent from the shredded wheat factory

[Bibio]

Thanks all. Off to Google silver soldering.

before you do anything. what type of 'metal' is it and what shape is it. is it hollow or is it solid?

a pic would help.

your never going to get silver solder to melt properly onto steel with a soldering iron.

[keith_d]

Lots of options:

1) Soft solder - melts at low temperatures which limits the damage to paint, but not mechanically strong and poor adhesion to steel.

2) Brazing - much higher temperature than soldering, brass melts around red heat but much stronger and with suitable flux has very good adhesion to steel

3) Silver solder - similar temperature and flux requirements to brazing also mechanically strong and has good adhesion to steel

4) Acetylene welding - higher temperature than soldering or brazing, but joins are as strong as the steel surrounding them.

5) Spot welding - not as strong as fusion welds and dependent on surface preparation. But if you know someone who can come up with a suitable pair of electrodes it's the least disruptive option for thin materials

You could probably use a TIG welder too, but I'd be very cautious about arc welding on thin materials.

[Nobbylad]

Thanks.

I've seen brazing rods online. I'm assuming I can use my blowtorch with them easily enough?

[Nobbylad]

Like this? http://www.amazon.co.uk/gp/aw/d/B002R0ON9U/ref=mp_s_a_1_1?qid=1377649043&sr=8-1&pi=AC_SX110_SY165

As opposed to this? http://www.amazon.co.uk/gp/aw/d/B002R0MKEK/ref=mp_s_a_1_2?qid=1377649043&sr=8-2&pi=AC_SX110_SY165

[Bibio]

the reason i was asking what and how thin the metal is because it might just melt when subjected to heat so brazing might not be suitable. for brazing you need the metal to be 'cherry red' and a concentrated area or the braze will flow all over the surface. there are ways to minimise this such as using clay or string.

[maviczap]

If not clamp it together and glue with an epoxy resin based glue

[yorkie_chris]

Yeah a pic would help!

Brazing with a propane torch is a pain, you haven't got the heat to get it hot so you just end up getting the whole jobby lot "warm-ish".

TIG brazing can be very nice, as can oxy-acet braze... or soft soldering... it's only a lamp lol.

[Nobbylad]

I'll get a pic up later. I know 'it's only a lamp', however it's the Doris we're talking about here and you know how it goes :rolleyes:

Anyway. .. it's potentially an excuse to buy more tools! :D

[yorkie_chris]

Aye but no point making an aviation quality TIG weld at vast cost if a gob of solder worth 10p that takes 30 seconds will do the job.

[Nobbylad]

Here are some pics. Excuse the bandaged leg in background, had a knee op yesterday so sat on my fat a$$ today lol.

http://i11.photobucket.com/albums/a161/nobbylad/20130828_111055_zps79bf712f.jpg

http://i11.photobucket.com/albums/a161/nobbylad/20130828_111110_zps4225b7be.jpg

If regular solder would do it, I have the necessary.

[Tomor]

Rivet :D

[dirtydog]

Blu-tac?

[Bibio]

i visioned some fancy pantz thing not a simple rose ring.

as tomor said drill and rivet the sucker.

GWS Nobby.

[yorkie_chris]

Or spot weld

[Nobbylad]

i visioned some fancy pantz thing not a simple rose ring.

as tomor said drill and rivet the sucker.

GWS Nobby.

Cheers Bibs

Would the brazing rod work better than solder?

[yorkie_chris]

Braze is stronger but it depends on the base material and getting the right flux for any process like that.

[Nobbylad]

I'll give soldering a bash (nowt else to do) and if it's carp, I'll get a fine flame nozzle for my blowtorch and get me some rods :D

[Bibio]

first off get yourself a rod of high purity silver solder and flux to suit.

file/sand the finish off from the surfaces to be joined remembering the edges. dip the parts to be done in proper flux.

use blobs of blu-tak on a surface to hold parts (not at the part you want to solder) then heat the area to be soldered then flow the solder onto the join. if you leave a small (paper thin) gap at the surfaces to be done the solder will flow into the gap and create a stronger bond. the area should be hot enough so as when you take the heat away the solder should flow without the flame being there.

you could use rosin cored silver solder which is easier to work with as you dont need flux.

if all else fails then wrap and twist the parts together using copper wire then solder all round.

[454697819]

tek screw it or self tap it..

sod the welding..

[nikon70]

as my dad would say, superglue it.... *sigh*

[Nobbylad]

if all else fails then wrap and twist the parts together using copper wire then solder all round.

Cheers fella. I ended up doing this straight off. Filed down the surfaces, bunged a shed load of flux on 'em, then wrapped them in some thin gauge copper wire and blasted them with the blow torch and some solder I use for plumbing jobs.

Job jobbed and I'm sure that means she'll need to do some jobs of her own to return the favour. .... if you catch my drift lol ;)

[nikon70]

too much information in that last post!!

well done sorting it tho

[Nobbylad]

too much information in that last post!!

well done sorting it tho

:smt096

[yorkie_chris]

Lol. All therapeutic... keep your spirits up with the knee and that...

[Nobbylad]

Lol. All therapeutic... keep your spirits up with the knee and that...

Indeed. .. I'm also currently researching materials to fabricate a smoker a la _stretchie_

I'm gonna smoke me some ribs :D