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HappyHammer
4th Jan 2005, 12:46 PM
OK I've been looking in the Herless cataldog at welders as I quite fancy giving this a go, after finding a short course somewhere. When I got there I found Arc, Spot, Mig - Gas, Mig - Gasless and Tig.

Can you guys give me some clues what these different welders are used for, I'm thinking an Arc welder for starters and general playing around. Advice on best gloves, masks, benches and vices gladly received also.

HH.

STEPHEN MILLER
4th Jan 2005, 01:57 PM
Welding guide

Arc Welder use a a transformer to produce a variable current and use a welding rod to create a weld the flux around the welding rod is used to remove oxygen from the weldig area but this becomes slag after thwe weld has been done and needs to be removed, Arc welding requires a bit of patience and practice can be used for steel,stainless steel,cast iron just requires different rod for each job

Mig welding is far the easiest to learn in a mig welding the gas removes the oxygen from welding area this is done by using migsheild or by a flux core in the welding wire Mig welders by feed welding wre from a roll down welding lead to a gun. Mig can be used for steel ,stainless steel,cast iron, aliminium but if you weld steel and aliminium you need to change the core in welding lead between types as aliminium wire builds up inside core as it is softer an rubes of and if dont change it comes out on your steel wire anc stuyffes up your weld. Advantage of Mig over Arc is better weld can be produced by anameteur because you dont have the risk of slag inclusion into weld but Mig is limited unless you buy a big three phase unit to the thickness of material you can weld

Tig Welders require a lot more skill machines are expensive good for stainless steel, aluminium, and a limited to material thickness Tig welders are an electric type of oxy welder but are more versitial

Spot welders are used for sheet metal so are limited in there use

Gloves best ones are long leather ones that are lined are blue or black in colour unlike lplain leather gloves they dont go hard.Welding helmet if you can afford one LCD that are self darken are the go make life so much easier. Good vice steel or cast irn will be fine Bench steel top one is fine you can just grind spatter just make the top at least 10 mm thick

echnidna
4th Jan 2005, 03:58 PM
For occaisional use an Arc welder is the most cost effective.
SHOCK HORROR - I have a GMC arc welder from Supercheap works quite well.
I thoroughly recommend an AUTOMATIC welding Helmet - much easier and safer than normal welding helmets. Mine cost the same as the welder cost ($99 each on special)

vsquizz
4th Jan 2005, 03:59 PM
Excellent advice from Stephen. Just a note, Mig is easier for a mug but as stated, in home handyman models is limited in its capacity. Mig is also badly affected by wind. Look at the cost of consumables before making a purchase.

A mig when changed from steel to Aluminium will require a liner and tip change in the gun to prevent contamination. It may also require a roller change.

Old arc welders can be picked up for next to nothing 2nd hand.

Cheers

HappyHammer
4th Jan 2005, 04:12 PM
Thanks a lot guys this is what I was after.

Squizz, I read about having to change wire, rollers, tips and gas depending on the metal you're welding which sounds a bit fiddly for a beginner.

Say I wanted to make a gate and weld some solid 10mm-15mm steel rod would the arc welder do the job?

On the mask I read a recommendation for an "electronic welding mask" any idea what this is?

HH.

silentC
4th Jan 2005, 04:42 PM
I'd go the arc welder. You can even make your own (http://www.huv.com/jon/jeep/Welder/portable-welder.html) with an old alternator. MIG is the only way to fly if you're going to do a lot of it but for mucking around, cheap entry, and minimal supplies, you can't beat the arc welder.

BTW there are health problems associated with welding. I can't say for sure but my mate who is a MIG welder by trade reckons his lungs have been stuffed by the gas.

Yes you can make a gate with an arc welder but why don't you build a forge and make a wrought iron one :D

I think the electronic masks adjust the level of light filtering electronically so you don't have to lift them up all the time to see what you're doing when not welding. I could be wrong. But I don't think so....

echnidna
4th Jan 2005, 04:49 PM
The automatic masks are like wearing sunglasses while you are messing around but darken instantly on the start of the arc when you start welding. No more flashes or blindness or sore eyes.

silentC
4th Jan 2005, 04:51 PM
A bit like Zaphod Beeblebox's 'Peril Sensitive' sunglasses... :cool:

HappyHammer
4th Jan 2005, 05:01 PM
Yes you can make a gate with an arc welder but why don't you build a forge and make a wrought iron one :D
You read my mind:eek: first make the forge then pummel and twist some wrought iron and a bit of welding to pull it all together.:D

HH.

GeoffS
4th Jan 2005, 07:58 PM
An arc welder is all you need for starters. I've had Oxy, mig and arc (also called 'stick' welding) gear. The arc does all I need these days. Arc is basic and a good learning tool.
WARNING about inexpensive 'auto' masks. Some cheap ones have been known to be 'slow'. That is, they didn't darken fast enough. IMHO I wouldn't buy one that didn't have a brand name - at least you would know who to sue when you went blind. Seriously though the fault can be hard to pick and not until you wake up with your eyes full of sand (that is the sensation you get when you have caught too many flashes) do you know you have a defective mask. It's your eyes that we are talking about and they are certainly worth more than $100 or so.
Cheers

vsquizz
4th Jan 2005, 10:02 PM
A good note about the auto masks above. When I last tried them I had the old sand in the eyes affect for a day or two after but I'm sure they are getting better. I pay the $12.00 instead of the $2.50 and get the gold lense in No 11 for GP stuff and No 13 when I'm doing low hydrogen pipeline stuff. Lenses are numbered between (I think) 6 and 15 for welders. No 6 is about oxy goggles and number 15 is so dark I can't see jack. I like my old fashioned CIG helmet.

For tacking up stuff like gates mig or stick will do but invest in some cheap magnetic welding clamps (which are definetly NOT Cramps). These are great especially when your learning.

Most welding machine repair shops have a rack full of 2nd hand welders for sale and a semi-professional machine (migs) can often be picked up for half the cost of a new machine. Beware some of the cheap imported migs, they use non-standard gear and you can't get basic parts readily or at reasonable cost.

Teach the family to avoid looking at the arc and yes, the fumes are not so good for you although a bit of welding around home is not likely to hurt. When I was doing a lot of boiler work they used to chest X-ray us every 6 months. I asked the Doc oneday wether the rads or welding fumes was gunna kill me first, he reckoned it would be a close run thing. They stopped doing the X-rays shortly after. I took up smoking out of spite:rolleyes:

Go the stick

Cheers

graemet
4th Jan 2005, 10:17 PM
I have a small oxy-acetylene Colt 22 from (used to be) CIG. Not much good for big stuff unless you braze, but easier to use for tube sections & sheet metal up to about 1/4", great for bending steel bars, cutting steel plate, loosening rusted bolts. BOC charge too much for cylinder hire, but I still wouldn't be without it, even if I only use it a couple of times a year. Very useful when making jigs and brackets where an arc welder would just blow a big hole in things.
Cheers,
Graeme

Tankstand
4th Jan 2005, 11:16 PM
I have a CIG easy arc welder, electrically adjusted choke, 150 amps, excellent for general work ( read handyman). I once hired a MIG unit with "coated wire" it was a pita. smoked like stick welding, and I used three of the mini spools!! bleeding expensive :mad: So avoid gasless MIG if you can.

Iain
6th Jan 2005, 09:01 AM
The masks are a variation on a liquid crystal display, press a button on your calculator and a number or line appears.
The line is invisible and activated by an application of voltage, it is also polarised so is effective in one direction only (try to read a display using polarised glasses).
There is a sensing unit in the vicinity of the visor and once a flash is detected the liquid crystal is activated thus darkening the visor.
As the signal to the screen travels at the speed of light theoretically you should not see the full flash.
Two screens in opposing alignment will create a more effective block.
Try rotating two pairs of polarised glasses in front of each other and see the effect, from no reduction in light to total blockout, this effect is also used for 3D movies with the glasses you wear being horizontally polarised with left and right lenses being aligned in opposite directions, normal sunnies are vertically polarised with a slight offset for northern or southern hemisphere (the good ones anyway).
If blinded on startup, change batteries, if you can see where they go :rolleyes:

Wood Butcher
6th Jan 2005, 06:27 PM
At work I have MIG, TIG and ARC welders. We use tig for mainly thin sheet and non-ferrous (stainless, aluminium etc) Mig for sheet steel and arc for every thing else. IMHO you cannot beat an ARC welder for home use. No hire on bottles, can take it anywhere and some of the smaller units you can do small onsite repairs without needing large power.
In regards to safety, as I am sure has been said many times in this forum, do not skimp on money. Spend Everything you can and buy the best, As GeoffS said, "It's your eyes that we are talking about and they are certainly worth more than $100 or so."

himzol
6th Jan 2005, 09:15 PM
Well from a total novice I can say that the only way I've managed to get two pieces of steel to stick together without frightening the Ka-Ka out of me was by using a gas-less MIg. Yes the consumables are expencive but if your not very good at welding (me) and only do it very rarly (me again) then this makes life so much easier.

For big jobs I get by Brother in Law who's a Boiler maker. :D

I would also like to add to other when they say dont skimp on safety stuff, and those magnetic clamps - work great mate.

Himzo.

scooter
28th Feb 2005, 09:09 PM
I thoroughly recommend an AUTOMATIC welding Helmet - much easier and safer than normal welding helmets. Mine cost the same as the welder cost ($99 each on special)

Bob, what is the darkening time (usually < 1 millisecond) of your mask. Are you still happy with it?


Cheers...........Sean the crusty slag

vsquizz
28th Feb 2005, 09:28 PM
Sean, They are OK for home workshop or occaisional welding. But if you burn two boxes a day forget it, well thats my experience anyway.

Cheers

scooter
1st Mar 2005, 08:15 PM
Thanks squizz, would only want it for v occasional home use so could be OK, will check them out sometime.


Cheers........Sean, who is auto darkening, just drop a router bit :(

bsrlee
1st Mar 2005, 10:32 PM
I learnt to weld with a 'stick' arc welder, and eventually I could weld 18ga (1.2mm) sheet without blowing too many holes in the join. I had a bit of a windfall, so I bought a small MIG welder, just a basic one with 4 position switches. Also had years of fun, but I found I wasn't doing enough welding to justify paying CIG/BOC rent on the bottle and I'd nearly worn out the moving parts. So I'm back to a baby 10amp arc welder for odd jobs.

When buying a hobby level (10amp) welder, or even a 15 amp semi pro unit, keep an eye on the 'duty cycle' - in warm weather specially, you can over heat the electronics of the unit, and if its a good one, it will shut itself down for 30 mins or so until the heat dissapates, so you have time for a coldie. IF its a cheapie POS then the blue smoke comes out & it works no more. Some smaller welders have a fan assist for cooling.

Also look at how the amperage is adjusted - some are just a rocker switch for 'full' & 'half', others have an infinitely adjustable transformer (toroidal) over their whole range. If you are going to be welding thin stuff, say less than 3mm, get the infinitely variable.

I haven't given Oxy a go, but a mate is very good with it & swears by TIG welding, but doesn't care of MIG. It seems that 'stick' & MIG go together, as Oxy & TIG go together - Oxy/TIG is certainly quick to change from one type of metal to another, but I think Arc/MIG is easier to pick up.

When welding, try to avoid light coming from behind you - I did most of my work in an open fronted shed & I found working with back lighting to be a PITA as it became very hard to see what you were doing. Depending on the welding helmet you get, you may want a job spot light to see what you are doing & avoid welding the bench instead of the job ;-)

wanne022
11th Mar 2005, 05:19 AM
im looking to build a dune buggy and will be needing to weld on some engine mounts, a few suspension pieces some mounts and similar. possibly some tubing on the framework. what kind of welding would be best for that? and what kind of equipment would you suggest? amps? is there a portable one that could hook to a car battery/engine(like if the engine is running on the car)?
Thnx
Eric

vsquizz
11th Mar 2005, 09:41 AM
Eric, crude emergency arc welders can be fashioned to run off a couple of car batteries for very short periods. Mig is the go for most things automotive. Hiring a small unit is probably your best option for all the reasons discussed above. After you have hired it, and if you like it, then you can keep an eye on the auctions for a secondhandy....what ever turns your crank.

Just a note on Tig and changing materials. Ferrous materials (stainless) require DC welding current and non ferrous (Ally) require AC welding current on tig machines. Therefore a good allrounder tig machine will be a transformer machine that provides AC, DC+ and DC- welding current. Somewhat more expensive.

Cheers