Torch and Welder?

Discussion in '<a href=http://www.lawnsite.com/buttons/jump.php?i' started by Tom_B, Apr 16, 2002.

  1. Tom_B

    Tom_B LawnSite Member
    Posts: 22

    Hey,

    I just bought my first welder,Its a Craftsman 100amp ARC welder and its pretty cool and works great but i do have some questions.

    Because this is my first welder im still not really great but im going through alot of sticks just playing around with some I beam i have siting around,Now i bought some of these "Cutting" sticks but they dont cut,Im guessing im either doing it wrong or maby they just dont work,Any ideas?

    Im Welding at about 70amps with 1/8 sticks and im wondering if thats either too low or too high?How do you tell?

    Now with the Torch Question,Im in need of something that cuts better and cheaper (blades) than my 10a sawzall,Now i was wondering about these Oxy Gasoline cutting torches,Do they work?If so are they safe? (Gas and cutting torch's dont mix,Do they?) If there not any good or not safe then should i just go for a regular old torch ;)

    Thanks for any help.
     
  2. Tom_B

    Tom_B LawnSite Member
    Posts: 22

    I forgot to add that i do have a big craftsman Mig but im not wired for 220 yet so i will be welding Mig in about a month,So i probably wont even be welding stick that much longer but i just wanted to ask some Questions.Thanks
     
  3. 75

    75 LawnSite Senior Member
    Posts: 992

    A general "rule of thumb" for stick welding amperage is: 1 amp per thousandth of an inch of electrode diameter - another way of saying it is: the amperage should equal the size of the rod in decimals. (I credit Chip Hayden for that definition - he posted it in a reply to another thread :) )

    1/8" = .125" so ideally, 125 amps. 70 amps with 1/8" is definitely on the cold side.

    For that machine, 3/32" rods would work best - around 90 amps or so.

    If the heat is set too "cold", it will be quite difficult to get an arc going and it may "stick" a lot. As well, the finshed weld will look like it is just sitting on top of the base metal - which in fact it is.

    Too hot and the weld puddle will be hard to control, there will likely be a lot of "spatter" (little balls of material stuck to the workpiece) and the completed weld bead may show lots of undercut along the edges.

    Your machine is probably AC only -which is fine, just that some rods don't work well on an AC machine. 7018 and 6010 both prefer DC current. A good all-around rod for your machine, IMO, is 6013 (and also 6011)

    I have never tried the "cutting sticks" (but I have heard of them) you mention so I don't what to say about technique, however I suspect the problem is there just isn't enough "juice" for them to work properly - assuming they are 1/8" diameter.

    Oxy-gasoline? :confused: Never heard of it.

    For general use around the workshop, both cutting and heating, a decent oxy-actylene or oxy-propane torch is a good investment. Get one with 25' of hose or so (most come that way) and mount everything on a torch cart so you can bring it to where you are working without needing a l-o-n-g torch hose. (I have 125' of hose on the work truck and I need it to reach many places, but on the home workshop set I just have 25')

    If you will be cutting a lot of material 3" - 4" square and smaller (tube, pipe, angle,flat bar) another good tool investment is a chop saw. It's basically a simpler and heavier-duty version of a woodworking miter saw.

    Hope at least some of that info made sense and is useful to you.
     
  4. Tom_B

    Tom_B LawnSite Member
    Posts: 22

    Hey 75,Thanks for the Reply.

    Heres the Site where they sell The Oxy-Gas Torches www.petrogen.com ,If you read everything they make it sound like a good investment but i wasnt sure.

    Thanks
     
  5. vipermanz

    vipermanz LawnSite Bronze Member
    Posts: 1,773

    wow!!!! i like that gas torch :blob2:
     
  6. GreenIsland

    GreenIsland LawnSite Member
    Posts: 27

    Just an addition-- The Petrogen uses are more for the salvage type markets -- they work great and are known for their ability to cut real thick metals-- Oxy- acetylene are in general for more precise cuts and more general shop uses the the oxy-gas. Both have their uses and limitations..
     
  7. chip hayden

    chip hayden LawnSite Member
    Posts: 29

    you'll be amazed how much you can "build up and cut down" with a arc welder and a cutting torch.
    i concur with "75" that 75 amps is a little cold for 1/8 electrodes. try a higher setting on some scrap steel and work down to around 90-125 amps. even try much higher[150-175a.] and see what happens. this way you get a feel as to where to run the machine.i'm sure you know what a good weld looks like -just try to match it. think of it like a caulking gun. you're trying to wash in and blend the filler metal with the base metal. you're trying to "homogenize" the two.
    i looked at the website for gasoline/oxygen torch and found it very interesting. antique torches ran on a similar combination but were pretty inefficient. i imagine the company has worked the bugs out. i'm totally in favor of any other fuel than acetylene[C2H2]. it' unstable, hazardous by-products[phosgene] and getting more expensive. uh-oh i'm heading towards that soapbox. i've used other fuel gases like mapp, propane, hipurity, and chemtane. so far i like chemtane the best because it's as hot as oxyacetylene but a lot safer. as far a i know, the only downside of all these other fuels is they don't produce the reducing atmosphere that O2/C2H2 does. that means you can't gas weld with the stuff. although i did figure a way to do it. it's hardly worth the effort. other than artists and cast iron weld repair people who gas welds anymore? i think that gasoline torch looks pretty cool. check the price and if you buy it keep us informed. sorry to be so longwinded, chip.
     
  8. 75

    75 LawnSite Senior Member
    Posts: 992

    Thanks for the Petrogen link Tom, too bad they don't have the prices listed there - although your US $ price would be about 1/2 what we'd pay here in Canada anyway........... :(

    Both at work and at home, since I use the torch for just cutting and heating oxy-propane works fine. Your normal 20 pound "BBQ bottle" is used which makes refills a snap. Mind you, you'll only go through one "easy-to-get-filled-on-Saturday-afternoon-and-fairly-inexpensive" propane for every 5 to 10 "have-to-exchange-it-at-a-welding-supply-outlet-that-is-only-open-weekdays-and-costs-a-lot-of-$$$" oxygen depending on how much cutting you do.

    One thing that oxy-propane isn't too good at can be shown by an example: Often in quarry or pit work, something like a receiving hopper will be set in a different location on a conveyor. Using the bolt holes already in the hopper legs as the cutting guide, new holes are torched into the conveyor. This saves having to do any layout work or handle the hopper twice - once to mark the holes, once more to set it in place for good.

    Oxy-acetylene heats up fast so the heat trapped by the hole in the plate you are using as your guide doesn't affect the tip. With oxy-propane, by the time it gets the metal heated up enough to cut the torch tip starts to disappear.
     
  9. chip hayden

    chip hayden LawnSite Member
    Posts: 29

    just saw a petrogen outfit in the local want advertiser. asking price was $750. you can probably burn a lot of other fuel before that price would be worthwhile. chip
     

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