- Thread starter Superbad
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not rude at all,I prefer straight up criticism. But I did practice weld on some scrap pieces and shaped them down with an angle grinder,and the pieces held together strong.
for a second I thought you were calling me
well,the blobby bit is about right
As above
cough,erm it is reasonable. I've welded in a new wing and pieces of panels. And have welded on two brackets under the slam panel for an intercooler.
I've not really weighed that up,or perhaps I'm doing that without realising.
A novice is about right.
I did consider mild steel but because with it being air/fuel entering in there,I predict rust will occur within.
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One thing we haven't talked about is your machine parameters, I gather you're using a 130A SIP which for 3mm alu means running it flat out to stand a chance of getting enough heat into it. Did you pre-heat the parts or weld them cold? A bit of pre-heat would probably help.
Are the parts totally clean and oxide free around the weld area? If so did you clean them with a stainless steel brush?
You said the flange is cut from alu plate but where has the tube come from? It might be a difficult alloy to weld as Runnach mentioned.
Also, what filler wire, 4043 or 5356?
Questions, questions, but the problem is that almost everything you've ever learnt about welding steel goes out the window when you attempt alu.
Are the parts totally clean and oxide free around the weld area? If so did you clean them with a stainless steel brush?
You said the flange is cut from alu plate but where has the tube come from? It might be a difficult alloy to weld as Runnach mentioned.
Also, what filler wire, 4043 or 5356?
Questions, questions, but the problem is that almost everything you've ever learnt about welding steel goes out the window when you attempt alu.
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Just to add my two francs, The weld you show looks typical of most transformer Mig welds, Now as wozza has deduced You are going to struggle with a 130amp MIG, even with the best large machine on the market and a spool gun its hard going, Now I would say a synergies or a TIG is the way forward BUT neither of these will be an option to you,
I cant really offer any solutions to you, sorry, other than say make it of a different material, I will however just give you a quick idea of the beast your dealing with, The first problem you have is material, If its only a casting, die cast mazac or similar its going to be hard going, very in fact, second problem is going to be cleanliness any slight oil spots etc within the castings cause nasty problems in the weld, third is where the fun starts, you have a "window" and this varies with the grade of material, around 1500-1800C is where it will weld, which is low, when it gets too hot it forms aluminum oxide which will not weld, cooler and it will not weld, this is the issue with transformer MIGS they cannot regulate the heat input, If this wasn't bad enough you have the thermal draw of the material, which makes the initial start of the weld very difficult to penetrate, then of course theres the joy of wirefeaders and birdnesting.....mmhhhh
I cant really offer any solutions to you, sorry, other than say make it of a different material, I will however just give you a quick idea of the beast your dealing with, The first problem you have is material, If its only a casting, die cast mazac or similar its going to be hard going, very in fact, second problem is going to be cleanliness any slight oil spots etc within the castings cause nasty problems in the weld, third is where the fun starts, you have a "window" and this varies with the grade of material, around 1500-1800C is where it will weld, which is low, when it gets too hot it forms aluminum oxide which will not weld, cooler and it will not weld, this is the issue with transformer MIGS they cannot regulate the heat input, If this wasn't bad enough you have the thermal draw of the material, which makes the initial start of the weld very difficult to penetrate, then of course theres the joy of wirefeaders and birdnesting.....mmhhhh
shenion
Tool Pack Rat
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The Miller weld calculator shows 1/8" at about 110-130A using 0.9mm or 1.2mm wire. I have tried it on my 130EN and it needed more power.
You would need a 180A welder to do the 3/16-1/4" you are working with. Will be very hard with a thick flange and thinner pipe.
I was able to do some decent alum welds with the 130. Start with the torch real close (1/4") then back off to about 3/4" as you get going with the settings on MAX.
A spool gun is not needed, but it will make it smoother. A good wire feed will work. Spool guns are for 0.8mm 4043 wire and that is only useful on 1/16" alum (the Miller calculator never recommends 0.8mm wire.) 0.9mm is what you will want anyway as you cant get enough heat out of 0.8mm and the feed rate is insanely high (had at 9 of 10 on my 130EN for 3/32") 0.9mm will feed easily with no birdnesting. 5356 feeds just like steel wire as it is considerably harder. But it is not supposed to be used on some alloys if it is to be used at elevated temps.
Do it in steel. It will be much easier. Alum MIG is really only doable if you are doing the same thing over and over in a production environment. It takes a lot fiddling with the settings and technique.
You would need a 180A welder to do the 3/16-1/4" you are working with. Will be very hard with a thick flange and thinner pipe.
I was able to do some decent alum welds with the 130. Start with the torch real close (1/4") then back off to about 3/4" as you get going with the settings on MAX.
A spool gun is not needed, but it will make it smoother. A good wire feed will work. Spool guns are for 0.8mm 4043 wire and that is only useful on 1/16" alum (the Miller calculator never recommends 0.8mm wire.) 0.9mm is what you will want anyway as you cant get enough heat out of 0.8mm and the feed rate is insanely high (had at 9 of 10 on my 130EN for 3/32") 0.9mm will feed easily with no birdnesting. 5356 feeds just like steel wire as it is considerably harder. But it is not supposed to be used on some alloys if it is to be used at elevated temps.
Do it in steel. It will be much easier. Alum MIG is really only doable if you are doing the same thing over and over in a production environment. It takes a lot fiddling with the settings and technique.
All that, but, if it's gas tight and on, why not just clean up the worst of the poo, clean it up really well with a SS wire brush and acetone, and smooth it out with epoxy. Spray it silver if you like.
It'll never be a testament to your welding skills, but it should work.
It'll never be a testament to your welding skills, but it should work.
Paul.
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I doubt if it is gas tight and attached, with the weight of the carb, and some engine vibration, changes in temperature etc, my betting is it'll fall off, my advice would be as per Shenion, do it in steel or make up the parts and take them to a pro to get welded
That is correct
It is actually 5mm
No,I started off cold. I will try the pre-heat
So so. After grinding down the height,there was areas that the grinder didn't reach. So I had opted for SS wire brush,works alot better
I got the tube off ebay
Good question. Didn't realise they were numbered,so I'm not entirely sure
Oh dear
Yes,I weighed that up and considered getting a platform for the carb to sit on. Even though I could be successful in making the parts,it's the internal condition of the tube. The A/F needs to flow through smoothly
Yep,it's seems that is the best solution. I think I need to realise my defeat
So this is where I'm going wrong
http://uk.youtube.com/watch?v=V_MiGrL9350
crayefish
Landy modifier extrodinaire
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I agree... do it in steel, then by the time it has rusted a couple of years down the line hopefully your ally skills will have improved and you can make an ally one
also, steel will conduct less heat from the hot manifold to the carb (might have problems restarting the engine)
one last thing... as the wieght of the carb is supported at the end of whats effectively a long lever, it would need to be quite strong, and ally has pretty poor fatigue resistance.
as for the welding, ive never tried ally, so you're doing better than me... well done for being brave and taking the plunge!
also, steel will conduct less heat from the hot manifold to the carb (might have problems restarting the engine)
one last thing... as the wieght of the carb is supported at the end of whats effectively a long lever, it would need to be quite strong, and ally has pretty poor fatigue resistance.
as for the welding, ive never tried ally, so you're doing better than me... well done for being brave and taking the plunge!
JayRS4
Si vis pacum, para bellum
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A non welding related problem i can see. Are you doing what i think and extending the intake manifold at an angle so the carb misses the brake servo. If you are, the rear runner length is going to be longer, you could have fuelling problems, and at worst end up running the rear cylinders lean and melting pistons. You might be better rotating the carb up instead, then you can use two equal 90degree bends. If this wasnt the plan, or if it`s been done successfully before, please ignore this.
crayefish
Landy modifier extrodinaire
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good point... best would be 90 degree bends then sell the sidedraught for a down draught. if its in good condition you shouldnt make a loss. while youre at it get a dell'orto instead of a weber. they tend to be better. i can give you the ebay address of a dell'orto seller in america who does em half the price of others. thats where i got my quad down draught dell'ortos (IR runner) for my V8)
other option is to remote mount the barke servo, but first option would be easier (personally i think down draughts are better and they also mean less stress on the manifold due to a smaller lever)
JayRS4
Si vis pacum, para bellum
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glad i`m not going mad after all. better still, if you`ve got the time/effort/probably money convert it to injection, there was an interesting article in Practical Performance Car many years ago expaining how it`s done, probably more hassle than it`s worth.
There`s always ITB`s Mmmmmmm
There`s always ITB`s Mmmmmmm
crayefish
Landy modifier extrodinaire
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NOOOOOOOOOOOOO! we'll have no talk of fuel injection on this forum! thats for the PCB soldering forum!
seriously... down draught dell'ortos... powered most of the worlds fastest cars in the seventies (mostly ferraris)
JayRS4
Si vis pacum, para bellum
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Alright, sub contract the techie bits to somewhere else, still got to make up the new intake manifold with collars for injectors and mounts for butterflys, nice little project in itself.
I fear we`ve gone a little off topic, never mind
I fear we`ve gone a little off topic, never mind
Yes,correct
aha...that is a good point. Always good to have fresh eyes looking at were I'm going wrong. There's a possibility that the fuel can be monitored per venturi
Yep,I've been looking at that recently
Yes,a DRLA or an IDF would be the answer. It would mean that I will have to buy a pinto downdraught fanimold. The price I've seen so far is £185. Also,with my intention for turbo application,I've been digging around on info about whether a Weber or Dell would be best suited. I know the Lotus used 2 Dells,there's been mention that webers are up for the job aswell. I do have a couple of Dells,so I can experiment which I prefer.
Oh please do,I can then make a comparison
yeh,I was also considering that. But with it being an ABS unit,it is a drawback. I have considered doing away with the ABS,and put some remote bias boxes in.
Yes,I saw that article. It did bring a certain amount of controversy,as many do not want to destroy a Classics authenticity. I did think it was interesting,as it would be a means to bring down emissions. But,my aim is to eventually put a turbo on,so it would be a blow-thru setup. Don't know what it is,there's something about an Old Skool style blow-thru setup
crayefish
Landy modifier extrodinaire
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Dont bother with and IDF (48)... its an all out racing carb which is either on of off effectively (also no choke). For normal driving it will have terrible fuel economy at part throttle. Even for my 6500 rpm v8 race engine I went with four DRLA's. MUCH better option. Weber 40's (downdraft) are suitable, but the same price and not as good as dellortos
Ill send you a PM with the ebay shop of the Dell'orto people. They do the italian ones, not the cheap spanish ones. Also, while they often don't have DRLA's on show, ask and they can sell you some for only a fraction more than the DHLA's they have. they're rebuilt, and have the steel bleed screw replaced with a brass one so it doesnt seize
enjoy
Ill send you a PM with the ebay shop of the Dell'orto people. They do the italian ones, not the cheap spanish ones. Also, while they often don't have DRLA's on show, ask and they can sell you some for only a fraction more than the DHLA's they have. they're rebuilt, and have the steel bleed screw replaced with a brass one so it doesnt seize
enjoy
