What to look for in a used Oxy Acet setup

[woodlandfarms]

In my previous post, I am considering the purchase of a used Oxy Acet system. There are usually half a dozen posted in our local area craigs on any given day, and the prices are in my zone for this implement. But having never been really trained on Oxy, what do you look for? I will have a neighbor who is a mechanic (Or his 15 year old son who has 4 years of welding shop under his belt) teach me but not sure what to stay away from or look for as most of the units are well loved.

Carl

 

[Mark @ Everlast]

Look for as much related attachments such as welding/brazing heads, extra gauges etc as possible.

A couple things about the torches from my perspective:

1) Victor, though I hate to use them myself, is well respected, and is largely considered to be the standard by which others are judged. Most cheap "box" store torches under store names are copies of this torch. Parts likely will interchange, if not the overall feel will be retained (if you like the feel of a Victor, that is...)

2) Harris, is a good respectable brand produced by Lincoln. It can also be found under the "Craftsmen" trademark from Sears, if it is used. They were originally made in the US, and some of the older torches carry a lifetime warranty. Then they moved to Ireland for production, and then elsewhere. I like the feel of them, but I also cut my teeth on them, so to speak..

3) Smith, a ITW brand which Miller is a part of, carries a lifetime warranty on their torch, and I believe it is still mostly if not wholly US made. Victor, well they claim US made, but a lot is made in Mexico now. I have a Smith myself. A word of warning...there was a period of time a few years ago that they dropped the lifetime warranty in favor of a 3 year one...But most of the lifetime torches have it printed on them..

4) ESAB, or Prestolite, Purox, and possibly other names, makes the safest regulators in the business.

5) Uniweld...an old name, but not a lot out there, and parts aren't stocked locally very much..>Often sold in auto part stores, and hardware stores.

Anything else, research it thoroughly...If it is compared to a Victor in the advertisement, it is a knockoff.



As far as what to watch out for.

1. Mismatched regulators...particularly some cheap looking one with a name brand one.
2. Make sure it has the flashback arrestors on it. If you aren't sure what they are google flashback arrestors and Oxy acetylene torches.
3. Make sure you have original crimped connectors on the hoses, aand not hose clamps
4. Make sure the gauges and the torch is not greasy or oily looking.
5. IF possible, check them out and make sure that when the torches are pressurized, that the gauges do not "creep" up in the pressure on the lower pressure side of things. Pay special attention to the Acetylene regulator. If the gauge has been changed out, it may omit the "red zone" which warns of dangerously high operating pressure which makes Acetylene unstable.

BEWARE of buying cylinders with the set. Just because someone sells you some with cylinders attached, doesn't mean you will own those cylinders when you take them in for refill. Most larger cylinders are leased, or rented and it is ILLEGAL for another company to fill them if they belong to another company. And you are in possesion of stolen property so to speak....Likely they won't do anything to you, but they may confiscate the cylinder. IF the original bill of sale can be provided, it should be good, unless it comes form an auction.

 

[deereman75]

I would add airco/cocona to that list. I have a cocona, and I love it. The only issue buying used, is they dont take abuse well, and cost a lot to fix. If taken care of, they are some of the best. I also have a smith aircraft torch, and I like it even more. I hear the old airco corncob torch is one of the all time best straight torches.

 

[cowski]

i prefer oxweld[esab] ,to me the premium choice.purox is also by esab.victor would be the most economical choice.smith would be good,backed by miller.you really need a cutting attachment and a brazing tip starting out.then you can add a rosebud or various heating or welding tips later.buying used get the biggest tanks you can.

 

[lostcause]

the topic of buying vs leasing gas bottles comes up a lot, so if you haven't read any of those threads, here's some basic advice:

go to the place where you will be getting your gases from and inquire about their policy on customer owned cylinders before you spend any money on tanks through a private sale. they will tell you what they want to see as far as bottle sizes and markings to indicate ownership. around here pretty much all 60cf & under tanks are owned, so they are pretty safe. virtually all tanks in the 125cf & larger sizes are leased, so you will need paperwork, or at the very least some fast talking with a clean cylinder. larger cylinders are far cheaper per unit to use than smaller ones, but if you don't go through the tanks very often, a smaller set might be cheaper to obtain and use.

as far as torches and gauges go, mark gave you plenty to sift through there. my only other thought would be how clean they are at the fittings, as in how many decades have then been in that box under the bench? and does the seller remember who was president the last time they were confirmed to work?

i also posted in your other thread with my opinions on o/a vs plasma.

 

[monckywrench]

Here's an idea:

Post CLEAR pics of any setup you are considering. Shoot them like you were gonna sell them on Ebay. List make and model of torch or combination torch handle and cutting attachment and note the accessories.

You could post the Craigslist ads first for help weeding them out.

If any doubt about cylinders, you could go with the seller and take the cylinders you are considering in for exchange. If the LWS says they'll swap, hand the seller the cash for the cylinders and exchange them on the spot.

Beware of cheap Victor copies. I've seen 'em with bad seals and fire damage. I refuse to resell them and scrap any I get in lots.

 

[Gary Fowler]

Best advise so far from Monckeywrench: Dont take the buyers word that he owns the tanks, take them to the local welding supplier and try for exchange. If the owner isnt willing to do that then pass on the bottles. Oxygen bottles require a hydrotest periodically and depending on the pressure applied last they may require retesting in 5 years. Latest test date should be stamped on the top of the bottle. You can Google all the info and how to read the stamping so you can be well informed.
My LWS charged me a $50 hydrotest fee for each of my bottles but just swapped me for new ones of the same size which is pretty well standard practice. TSC will only take their bottles back and no one elses so forgot about checking there.
I think the tips and parts for Victor and Uniweld are inter-changeable. Just about anything on the Victor equipment can be rebuilt and parts are usually available at the welding supply. Gauges have to be sent off for repair since you really need to know what you are doing to keep from blowing your self up on the high pressure stuff.
Mark hit the hi-lights on checking the gauges but you have to have an oxygen bottle with at least a few hundred pounds of pressure to checki it. Acetylene will only have about 200-250 PSI when full, but the same thing applies. Install the gauges on the bottle, Back off the pressure adjusting thumb screw by turning it counterclockwise till it is loose and spins freely, if you screw it all the way out no problem just put it back in a few turns and take care not to crossthread it. Turn the valve on top of the bottle really slowly in counter clockwise direction to open the pressure to the gauge. The tank pressure gauge should slowly come up to show tank pressure. The other gauge is for torch or line pressure and should stay at zero. NO FLOW should be coming from the torch. You need to check this to make sure there is absolutely no oxygen or acetylene coming out. Acetylene you can smell, the O2 you will need to feel it on back of your hand or cheek. IF no creepage of dials, then turn off the torch gas valve (red hose) and the O2 at the cutting head, leave the valve on the mixing barrel fully opened, then slowly turn the pressure regulator thumbscrew clockwise to build pressure to about 40 PSI on the o2 line and 5-7 psi on the gas (DONT EXCEED 15 PSI ON THE GAS -(RED ZONE ON THE GAUGE ) The gauge should hold the pressure without creeping up. If it starts to creep up, then the diaphram in the gauge is bad and you need to immediately shut off the tank valve and unscrew the thumbscrew till all pressure is removed. This should be done everytime you finish using your torch also to avoid injury from a blown diaphram along with slowing opening the O2 tank valve each time.

If the gauges check out good, then check the torch valves, they should be free movement and not overly tight. Remove the cutting head and check the 2 o-ring gaskets on the then, they should not be totally flattened and should be supple (press your fingernail into them and see if they are soft or like wood) These are easily replaced for about $4 but hardened and flattened orings are indication of misuse of torch. The cutting head and or welding tips only need to be two finger tight when properly tightened although some folks think because they have 6 sided nut that they need to wrench them down.
Check the mixing barrel valve to assure tight shut off, no acetylene smell and no O2 leak. Reattach the cutting head, open the )o2 on the mixing barrel, make sure the O2 valve on the cutting head is closed (2 finger tight should be good). If no leak, you should proceed to light the torch. With torch striker handy (dont use a cigarette lighter) open the gas valve about 1/4 turn or less, and strike the flint lighter, you want enough gas so that it isnt producing long strings of carbon in the air but not much more than that, then open the valve on the torch to adjust the adjust the flame
For most tip sizes 00 thru 2 about 5-7 psi on gas and 30-40 on the air is plenty. If the torch adjusts properly without popping and going out, then you likely have a good torch. IF it pops and starts a high squealing sound, immediately shut off the gas valve followed by the oxygen valve valve. The squealing means the the flame has sucked back inside the mixing barrel and is burning inside. Failure to immediately shut off the oxygen and acetylene will cause the mixing barrel to get hot and eventually get hot enough to melt and explode. This is done in just a few seconds so immediate action is required.
If you have never used a torch, I would suggest you get some instruction from a qualified person. These things can be extremely dangerous if misused .
I have covered just a few of the things that you need to know and understand prior to use.

 

[monckywrench]

Uniweld have made and make a large variety of torches so post the SPECIFIC torch.

Some take Victor, Harris, or Airco style tips (the relevant patents ended very long ago and the famous brands also make torches which take each others tips so they can compete against established "fleets").

Uniweld make an interesting mix of stuff. I have one whose handle is Victor-compatible but whose cutting attachment takes the (arguably better) tip-mix Airco tips. I have no problems with their quality.

Again, post specifics so you don't get stuck with an unsupported model from any brand.

 

[rcowan]

I ask my LWS about swaping tanks before I bought my set-up. Be mindful of gauges/valves that don't hold pressure(ask me how I know).

RC

 

[bcp]

About 50 years ago a welder told me anything without "Air" in the name was OK.

Bruce