Welders

[muppet_man67]

Ive heard that gasless migs are carp, but why? are they same as ARC in that you have to chip away the flux? or Is it mostly just because they tend to be aimed at handyman type stuff and are therefore cheap and nasty? I have no problem with getting a bottle etc

There are a few Gas/Gasless welders on ebay that can go for around $300 would they be worthwhile or just an exercise in pain and frustration. how imortant is it to be able to adjust the current. some of them just have two setting min/max. These welders don't appear to come with gas regulators either. so how much might that add to the cost.

Am I better off going to a shop and paying a premium.

[mightymouse]

Not an expert welder but here's my 2 cents worth.

Not a great fan of gasless welders, however for around the $700 mark many offer both. Its a once in a blue moon job the hire on a bottle needs to be considered although the welds are poorer IMO with gasless.

Personally if you have the money and space by a larger gas mig - its extra capacity will be used - too small is a pain.

TIG is good, but same story - don't by too small or low duty cycle as its false economy. A water cooled torch is really required for long runs. TIG isnt ideal for large structural type welds

[gwagensteve]

I agree NEVER buy a mig that doesn't have a facility to run solid wire and gas.

I ran Flux core or "gasless" Mig for years and years. Once I went to gas, I have never looked back. Hire on a bottle is about $120 a year from memory from BOC, and it's about $70 a fill. A fill lasts at least a 5kg roll of wire, which is a lot of welding. Ignoring bottle rental, it's actually dearer to weld with flux core as the wire is MUCH dearer and the spools don't carry as much steel. (i.e a 5kg spool of solid wire = a 4.5 kg spool of flux core) so you have to throw more wire into the same job.

Flux core does leave slag like arc welding but it can be harder to remove. This makes doing multiple runs tedious. It's also far more smokey and produces more spatter. I keep a 450g spool of flux core in the draw in case I need to get something finished and run out of gas/solid wire.

Some more thoughts - Don't buy a welder that will only take 500g spools. 500g spools are very expensive and you will get sick of changing them.

Mine takes 5 kg, but "commercial" welders take 15 kg spools.

Apart from changing a few tips and a couple of nozzles, I have spent no money on my welder since I got it in 1996. IT's been fabulously reliable. Mines a 140A ESAB 10 amp unit.

Just some of my thoughts.

Steve.

[muppet_man67]

why does everyone rent them? are they expensive to buy. different to an LP bottle?

[muppet_man67]

you're no longer alowed to own your bottles, is a safety and liability issue.

BOC will not fill bottles, they only exchange

what a load of crap. your bottle your responsibility. I would have thought that there would be more liability issues with hiring them out. oh well I guess everyone get stuck playing their game.

[muppet_man67]

thats cool, but when was the last time that you got a BBQ bottle tested? or have you ever used your car, when you should have changed the oil a 1000k's earlier

the reality is that people don't do things when they should, so BOC do it for you, they also know that the bottle is safe for their staff to be around.

Ive never had a bbq bottle long enough for it to need testing. however if it is due for testing then then they can refuse to fill it. I thought argon was an inert gas, so in theory it should be safer then lp, unless its stored under massive pressure.

[muppet_man67]

just did some research sounds like they fit lots of pressure in these bottles 200bar

[gwagensteve]

Buying a bottle wouldn't be cost effective - they'd be pretty expensive - they are far more specialised than an LPG bottle. I can't see the advantage in owning a bottle - it becomes my responsibility then, whereas currently I don't have anything to worry about.

Have a think about the logistics though - I can swap my bottle at any time at any BOC Gas&Gear shop, it takes 5 mintues. If I had to get my own bottle filled, I'd probably have to wait around, they wouldn't do it on saturdays..... come back in three hours etcetcetc, quite apart from the liability of a damaged bottle exploding during filling.

The rental system works pretty well.

Steve.

[mightymouse]

I wonder given the range of gases, and the various filling techniques / pressures etc if a fill your bottle is really practical at the local level. I suspect they would have to be taken to a central filling plant. Delays, trucking costs, what happens if your cylinder fails etc etc all make it very difficult.

No I think the rental system is probably the most workable solution - even though I have my yearly bill right in front of me now.

[muppet_man67]

looking at this one http://cgi.ebay.com.au/Cara-MIG-MAG-WEL ... p_shipping
they are going for $390 buy it now from an online store, however the ebays have been going for about $250