How do I weld up a sump without making it look like crap?

[RAd28]

Hi all,

Been toying around the last few days practicing welding on a spare sump i've got, so far i've just cut slots in it with a wafer thing disc, then proceeded to weld them up, I've tried MIG and OXY with mixed results, the MIG gave me nicer welds on the straights, but I can see i'm gonna have issues on the corners etc. the Oxy makes it easy to seal up in all areas, but i can't get it to look neat (MIG spots are giving me grief). So I figured MIG up as much as I can, then OXY the trouble spots...I thought all was going well, so I got some thin scrap sheet metal and proceeded to practice some more... it was here that i realised how much trouble i'm in for. It seems that the cutting and welding up an old sump didn't give me any introduction to shrinkage/warpage probably because of the shape. where as flat scrap warped like the minds of a doped up hippy...

So basically, I need advice mainly on how to reduce shrinkage... I've got the MIG set on the lowest voltage setting. and i'm struggling to get travel speed fast enough to keep the heat out. I found that I could manage a decent run on the scap sheet, then I found that after an inch or two it would just start crackling (one website described it as a machine gun) but I've got no idea why...

Anyone able to offer any advice? Happy to hear all suggestions...

[Justo]

I have only ever seen 1 sump being welded before so i'm not an expert by any means but heres how I saw it done. it was being reduced in depth and was form a holden 202.

The welder welded a few tacks around at the corners with a MIG doing opisite corners and waiting for a few seconds between each weld till it cooled down a bit. then he did a tack in the centre of the straight sections and let it cool between tacks. once all the tacks were done he did very small sections at a time (about in inch) on opposite sides and letting it cool between welds.

It looked good in the end but he did need to use a hammer near the end to make sure everything lined up as there was some distortion. he used a blowtorch (light blue flame) on it in the end but I'm not sure why maybe to check that it wouldn't warp and break the weld.

[Tweak]

Tig it. Much neater weld and its more controlled. But the factor is the heat.........
Seems your in abit of a hard spot. May be easyer to get a intire new sump made up out of alloy

[RAd28]

Tig it. Much neater weld and its more controlled. But the factor is the heat.........
Seems your in abit of a hard spot. May be easyer to get a intire new sump made up out of alloy

Basically, my options are:

1) don't modify the sump (and risk poor oil supply)
2) modify the sump my self, using the tools I have (MIG & OXY)

I figure I have time and patience on my side, and If i make a cock up of a sump, another one isn't gonna cost the earth...

[takai]

Tack it all around, then (seeing as your welder cant really do thin sheet well) mig it up in short bursts on opposing sides about an inch at a time.

[legend]

x2 like Takai suggested thats how i would do it

[RAd28]

alright.. sounds like a plan, I'll give that another shot tomorrow night... Any tips on how to make the stop/starts less obvious?

[takai]

Linish it.
Will help with seeing where you have missed bits on a leakdown test

[matty12]

thin stuff you will have to pulse it when using the mig..When doing sheet metal i do a little burn just to the point where it starts to get too much heat in it then stop.Wait until it cools so the bright orange goes away then go again.

Oxy will come down to technique so travel speed and filler speed etc.

[skiddz]

why do you care what it looks like? surely it couldnt look any worse than owens manifold welded with bird poo

[oldeskewltoy]

to combat the heat/warpage... find an old bare block, bolt the pan down when you do the work... it might just keep the warping to a minimum

[af300e]

to combat the heat/warpage... find an old bare block, bolt the pan down when you do the work... it might just keep the warping to a minimum

Definitely do that.

I built a bigger sump with gates for a rwd 3sgte and used the gen 3 alloy sump instead of an engine block as a heatsink/die.
The tin sumps are super susceptible to warping during welding.

Another way to help prevent warping is to ensure that the two pieces you are joining are actually butting together before the weld. If you are filling cuts then the weld shrinks as it cools and pulls the whole thing out to shit. Butting the panels together and using as low a current as possible means that there is less chance of it shrinking.

[RA23]

Pulsing works well with a MIG on thin sheet. Requires some practice though. Try on some scrap first. About 1 second on, 1 second off for a start.
Also can you go down in wire diameter?
What can also help to get rid of the heat quick is placing a few wet rags around the weld.

[manny]

You want to use the stitch MIG welding technique
Have a read of this info and watch the video
MIG Stitch Welding

[timbosaurus]

Hi Rad, a couple of things to insure are:

Complete cleanliness. While this also affects weld strength, it is most important for a consistant weld. Anything but beautiful clean steel could be the cause of that spluttering you're having. You are using sheilding gas?

Tacks. Some people say to tack every three inches, but i usualy tack every inch. Just a small tack that won't get in the way of the final pass.

I'll be surprised if your welder cant weld thin metal. Maybe the voltage and wire speed is that low that you have to travel too slow and are heating/warping too much? While practising, up the voltage and wire settings (till you can pass quickly without blowing holes), increase your torch travel and see how it goes.

For a sump, I would actually prefer oxy. I think it is perfect for that! Tack every inch, make sure the metal meets perfectly everywhere, and you shouldn't even need filler rod. Oxy does put in a lot of heat, but since you can get inside the sump to smooth it out, it shouldn't be a problem.

[mullett]

Wire is an important factor too...if you're using heavy wire, you'll need high amperage to melt it, introducing more heat to the weld, and you can't weld slow enough on a thin metal. 0.6mm wire would be great for this, don't use 'flux cored' gasless wire, it's junk. You welder should have a low enough amperage setting.

What breed of welder is it? If it's a cheap chinese MIG, you might be better off with the gas torch, or tack it all together with the MIG and get it TIG'd up professionally.

-RM.

[RAd28]

Wow... thanks for all the advice guys, some really good stuff in there...

takai - I will be linishing it when i'm done, just wondering how to make it look neater though before hand... more of a side note that one...

matty12 - I tried using the MIG on the spot weld setting just to basically spot it all up, but for some reason it didn't want to work... it made all the right noises, but the wire didnt' feed through, and to be honest, I didn't try acctually welding with it.. just pulled the trigger to test the pulse time, but there was nothing. don't remember hearing the gas either. I figured I could maually control the spots well enough (see end notes about this one)

Skiddz - starting out welding this kinda shit is hard... Owens welds might have looked like crap, but we've all done them, he just wasn't afraid to show them off...

oldeskewltoy - That's I can see your point there, But i question the fact that when you remove the pan from your dummy block it's just gonna warp anyway... but less so i guess because of heat dissipation...

af300e - Interested to see pics if you got them... I'd love to see pics of the gates, I have an idea for my gates, but as always, input would be awesome

RA23 - as per my reply to Matty12 regarding the spotting, as for wire diameter, I'm running 0.8mm atm, but I the welder can go to 0.6 if i need to... what thickness material is 0.6 good for? do I need a new gun at all?

manny - Thanks for that, will definately check it out

timbosaurus - I'm doing my very best to keep things clean and neat etc etc I managed to learn very early on that anything less then virgin metal isn't gonna weld... as for gas, i'm using Argoshield...
Normally i'd tack every few inches too maybe upto a foot apart if the strength in the plate is there, but with this stuff i've been trying to tack every 15-25mm apart, just tiny ones though. this in itself seems to be a fair challange...
I'm currently using the lowest voltage setting (don't know the value), and wire speed to suit, I tried cranking it up a notch to see if picking up travel speed helped with blowing holes, but i didn't get far with that, it blew holes almost straight away...
I might have a crack at test welding some of this sheet with the OXY, see how I go with that... it might be alright, because it's so thin i'll need to keep the speed up which might keep the heat out...

mullet - it's a SIP Ideal200 made in the mid 80's... made in London...

This afternoon I put more effort into getting a test weld to look nice and neat... Cleaned and prepped 2 pieces of sheet (not too small) about 30-40cm long... then I positioned them, used welding magnets to hold them in place on one side, and a thick piece of flat bar on the other side to act as a straight edge... I started tacking them together, and this is where the first of my problems start... I can (almost) never start cleanly with a weld... usually I start with the MIG wire resting on my work piece (tell me if this is bad) then pull the trigger, the thing just seems to jump, break the wire then i have to start again. anyways, managed to get it tacked up (reasonably) well, and it was still looking pretty straight... so I started doing stitches (waiting for the orange colour to fade between runs), vertical down as one of the guys from work suggested, and I managed to get 2 or 3 fillets about 20-30mm long looking quite respectable... but that was the end of that... from there on all the welds started looking worse, and it ended up blowing holes in almost all fillets after about 15mm... and back to that problem of not making a proper arc... I'm thinking that i'm having issues with my earth lead, it's just a spring clamp style (similar to a jumper lead) but its getting weak in it's old age, and isn't really clamping tight on thin sheet, i'll try again tomorrow with some thicker plate to sandwich the thin stuff...

bought an auto darkening helmet too... makes spotting alot easier...

[matty12]

post some pics of the welds you are getting,it may help identify problems.

practice makes perfect.

Ive just bought a tig welder, i was abit ordinary to start but now ive done a few hours im now ordinary.

[floppy]

Hey!

If you need an 18R block I have one here you can use.

The only reason I was keeping it around was to do exactly what you are wanting to do, keep a sump from warping!!

Give me a ring, I have tomorrow off.

Dave

[rolla 36]

hey mate when tacking or starting a new weld are you cuting the wire (about an inch)

i could tell you why u need to do this but just but that dark section of wire does not melt well and that is why it jumps and spits

to try to stop distortion (nerly imposable but can get it close) try back steping or back weld what ever it is called cant remember now is what this means is weld like this <-- <-- <-- that means you weld then stop wait for the glow to go away (like was said earlyer) then move about an inch away from where you started last time (after cooling a little) thenweld back to the point (i.e again <---- <---- <---- <----)

and also make sure you try to clean the area as well as you can

i am sorry if that makes no sense if you dont under stand please measage me and i will explain on the phone maybe it will sound a bit beter then wat i just wrote