Screwdriver
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The only online shop I have found so far wants EIGHTY QUID for 1 kg of sif no. 8
That's more than the whole stove cost.
That's more than the whole stove cost.
- Thread starter JonnyAlpha
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The nickel rods arent cheap either
Screwdriver
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Well, I need a cheap solution....
Shox Dr
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R-tech welding sell small packs, there's also plenty on ebay
C
Chris Stevens
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You dont need 1kg to repair that crack. Consumables for CI repair are costly though, and that has to be taken into account when telling a customer how much.
Not that difficult to get the price of the rods back on one job though.............say an exhaust manifold costing £500 to replace, most would be happy to pay £80 for a repair.
Screwdriver
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There may be "plenty" on eBay but none of them come up in a search for sif no. 8
Can't find any on R-Tech either. You have to remember I have no context for this material so a direct link would be appreciated. I realise I don't need 1kg but there is always (usually) a law of diminishing returns for buying too small a batch.
Can't find any on R-Tech either. You have to remember I have no context for this material so a direct link would be appreciated. I realise I don't need 1kg but there is always (usually) a law of diminishing returns for buying too small a batch.
Screwdriver
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R-tech is still 60-80 quid for minimum order of 1 kg
2.4mm rod is cheaper but still way too expensive for this job.
2.4mm rod is cheaper but still way too expensive for this job.
Sif # 8 is a trade name. Search the internet for c11 phosphor bronze and you might(?) get more/different results, doubt the prices will improve much if at all though. It exists as 0.7kg MIG spools too which should be a chunk cheaper than a 1kg pack of cut lengths for TIG... MIG stuff is probably max dia of 1.2mm which isn't exactly a bad thing but if you want thicker buy some thinner wire and plait 2 lengths together with a cordless drill
Nickel iron electrodes are usually available in much smaller pack sizes so cheaper but dunno if that applies to decent brands or just junk? Can knock the flux off if for whatever reason you want/need to use TIG (bearing in mind what's been said about heat input). Can also buy commercially pure nickel wire cheaply (google ni200 wire) but unlike 'pure' Ni welding wire there's gonna be no control of impurities and it's probably leaner in useful "stuff" added to welding consumables
Nickel iron electrodes are usually available in much smaller pack sizes so cheaper but dunno if that applies to decent brands or just junk? Can knock the flux off if for whatever reason you want/need to use TIG (bearing in mind what's been said about heat input). Can also buy commercially pure nickel wire cheaply (google ni200 wire) but unlike 'pure' Ni welding wire there's gonna be no control of impurities and it's probably leaner in useful "stuff" added to welding consumables
Screwdriver
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Meh. I'm going to stick to what I know and oxy braze it with cheap and cheerful silicon bronze or whatever it was I used last time.
I'll post the results here though and bore you rigid with the video!
S.
I'll post the results here though and bore you rigid with the video!
S.
C
Chris Stevens
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968 on Ebay, 12 rods for £12 which seems reasonable. I would have thought for the sake of £12 tig brazing was worth a try?
Bill Edwards
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My local suppliers sells individual nickel rods and they're decent ones. They aren't very far off £2 each.
If you're poor at stick then you'll have to go with what you know, for someone good with stick that'd be my choice.
I would never, ever get enough localised heat to braze on something like say an engine block/head or indeed anything I cared about. The heat difference is what kills cast, it has to be kept at an even temperature and done slowly, otherwise you're relying on luck.
If you're poor at stick then you'll have to go with what you know, for someone good with stick that'd be my choice.
I would never, ever get enough localised heat to braze on something like say an engine block/head or indeed anything I cared about. The heat difference is what kills cast, it has to be kept at an even temperature and done slowly, otherwise you're relying on luck.
C
Chris Stevens
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Done much tig brazing bill?
Richard.
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I'm with Bill
A cast iron repair is easily weld able if done properly.
A properly produced weld with a decent cast iron type filler is a stronger joint than a braze.
Before you ask yes I've done a fair amount of tig brazing.
C
Chris Stevens
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Thing is with a good number of cast iron repairs, is the casting is likely to be dirty (an exhaust manifold or engine block for instance), and in cases like this I have always found it easier to make defect free repairs with Tig brazing rather than MMA, which is a do or die process, which doesnt offer the possibility of gently heating the area to be repaired, to assess just how dirty the casting is before making a repair.
Not so if the repairs are on new of very clean castings, but unfortunately most are neither new or clean, so its certainly worth looking at tig brazing, especially for those who have never tried it before.
Not so if the repairs are on new of very clean castings, but unfortunately most are neither new or clean, so its certainly worth looking at tig brazing, especially for those who have never tried it before.
Richard.
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Surely you wouldn't entertain carrying out any repair whether it's brazing or welding without first cleaning the part.
I've never tig brazed cast iron before dispite done a good amount on other things.
I've brazed it with OA and I've mma welded it and tbh my preferred method is tig welding it with Ni50.
Small parts get done very hot and slow cooled. Big parts are done as cool as possible as it's impractical for me to try and heat them up.
As bill said which ever way you do it the key is consistancy in temp and stress relieve.
Uneven expansion or contraction and your part has had it.
I've never tig brazed cast iron before dispite done a good amount on other things.
I've brazed it with OA and I've mma welded it and tbh my preferred method is tig welding it with Ni50.
Small parts get done very hot and slow cooled. Big parts are done as cool as possible as it's impractical for me to try and heat them up.
As bill said which ever way you do it the key is consistancy in temp and stress relieve.
Uneven expansion or contraction and your part has had it.
Screwdriver
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Thanks. Well I'm not going to get any better at stick by not doing it so I'll pop into my local supplier and see what they've got. If I can pick up a few nickel rods at a sensible price I will.
I assume since my broken lid is such a small piece, I might as well get it good and hot before I weld it, then let it cool slowly. I'll probably clamp it to a bracket and heat that too.
Would you recommend peening immediately after welding? Would you weld it all in one go in say 1-2 inch sections with a minute or so between welds?
There's a video of the job in the projects section and I'll be videoing the repair come what may!
http://www.mig-welding.co.uk/forum/threads/fancy-french-stove-restoration.67381/#post-881957
S.
Bill Edwards
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No.
But brazing requires the part to be heated a lot, I don't need personal experience to know that. With heating is the hardest part as it must be done slowly and uniformly, there's no way to escape that.
