How to use a cutting torch

[dian]

hi everybody

after having read this and seen the vids, the question is: why would one get a plasma cutter at all? (i didnt know a o/a cutter could do this, never had one before)

[Sandy]

hi everybody

after having read this and seen the vids, the question is: why would one get a plasma cutter at all? (i didnt know a o/a cutter could do this, never had one before)

At a hobby level, there are times where plasma suites the need better or plasma has a certain convenience factor. There are also time when O/A suites the need more or is more convenient. And there are times where it is a toss up and just doesn't matter. Either/or, make a choice. Unless you have owned both you prob ably won't be able to conceptualize any of those scenarios. Owning both you won't be able to get me to get rid of either. If a person only has one and never owned or used the other I suppose you'd learn to do everything thing you needed to do with the one, coupled with other tools of course.

[farmall]

If I did a bunch of sheet metal I'd go plasma, or if I had a lot of machine cutting of not-very-thick plate to do. Plasma is Very Nice for beveling plate and pipe in-shop.

I can afford plasma but don't have enough use for it to get one yet. For what I'd have in a low-end plasma I have multiple sets of OA gear and a variety of tank sizes.

As to SEQUENCE, buying OA first is generally the way to go because it's so versatile and portable.

[killdozerd11]

Thank You for the videos Irish learned somethings
I never thought of turning up the O2 that high but after seeing your vids it works quite well

As for the guys out there that don't get it yet O/A is for doing most work but where plasma really shines is thin material or aluminum

Any were heat distortion is not acceptable

Hey was that bolt a little warm ..I could tell by the smoke coming off your glove ..he who hasn't done that one a time or two has never done any welding or cutting

Good demo i have had to cut seized bearing races off truck axles the same way

[mla2ofus]

I've wanted to get a plas for several yrs but just can't justify the cost for what I'd do w/ it. Most of my projects are sq tube, pipe or angle iron and the chop saw handles them quite well.
Mike

[mla2ofus]

[QUOTE=killdozerd11;584017

Good demo i have had to cut seized bearing races off truck axles the same way[/QUOTE]

And that's one of the many reasons I like the scarfing tip. Less chance of nicking the shaft. The only drawback to a scarfing tip is most of them consume a lot of O2.
Mike

[wirehead]

Where a plasma cutter really shines is cutting nonferrous metals, like aluminum, brass, and stainless steel. You CAN cut stainless (and others) with OA if you use a steel wire or rod along the cut to the supply the iron for the O2 to generate the heat to melt the metal to be cut. This molten metal gets blown out of the kerf by the O2 stream much like a plasma cutters action, though the heat source is different. Not very efficient, but if you NEED to get through stainless, and don't have a plasma cutter, sometimes you just gotta do what you gotta do.

[irish fixit]

hi everybody

after having read this and seen the vids, the question is: why would one get a plasma cutter at all? (i didnt know a o/a cutter could do this, never had one before)

Don't let all this writing about o/a make you think I'm down on plasma cutters. I'm not and as you can see in my sig I've got a good big one. I use it a lot and love it wouldn't be without it etc. Plasma is better for thin metal than a torch no matter how good you are. Though there are some on here who are better at thin metal with a torch than I am. They both have there place. I use plasma for thin or if I'm in a hurry and doing a lot of production even thicker stuff up to 1/2". Over 1/2" even with my big plasma it starts getting slow enough that I can do just about as well with a torch or even better. Plasma tends to leave a tapered kerf when doing thicker stuff that a torch doesn't .

Also plasma has a much shorter learning curve compared to a torch. It's a lot easier to get a good cut with a plasma.

That said if I was just going to have one or the other it would be a torch hands down. Just to versatile. I can heat and bend with it, braze, cut, and even weld if I have to.

At a hobby level, there are times where plasma suites the need better or plasma has a certain convenience factor. There are also time when O/A suites the need more or is more convenient. And there are times where it is a toss up and just doesn't matter. Either/or, make a choice. Unless you have owned both you prob ably won't be able to conceptualize any of those scenarios. Owning both you won't be able to get me to get rid of either. If a person only has one and never owned or used the other I suppose you'd learn to do everything thing you needed to do with the one, coupled with other tools of course.

I still don't think a plasma is as versatile as a torch.

If I did a bunch of sheet metal I'd go plasma, or if I had a lot of machine cutting of not-very-thick plate to do. Plasma is Very Nice for beveling plate and pipe in-shop.

I can afford plasma but don't have enough use for it to get one yet. For what I'd have in a low-end plasma I have multiple sets of OA gear and a variety of tank sizes.

As to SEQUENCE, buying OA first is generally the way to go because it's so versatile and portable.

Agreed.

Thank You for the videos Irish learned somethings
I never thought of turning up the O2 that high but after seeing your vids it works quite well

As for the guys out there that don't get it yet O/A is for doing most work but where plasma really shines is thin material or aluminum

Any were heat distortion is not acceptable

Hey was that bolt a little warm ..I could tell by the smoke coming off your glove ..he who hasn't done that one a time or two has never done any welding or cutting

Good demo i have had to cut seized bearing races off truck axles the same way

I've wanted to get a plas for several yrs but just can't justify the cost for what I'd do w/ it. Most of my projects are sq tube, pipe or angle iron and the chop saw handles them quite well.
Mike

You're welcome. I started running my oxygen up higher after some talks with a local welder who can make some of the most beautiful cuts with a torch you've ever seen. If you think I'm good you should see him.

Plasma also shines on stainless.

Yes it was warm. But I was in a hurry to keep the video short so didn't reach for the pliers like I should have. That's hard on gloves when you do that.

I understand about the cost of the plasma. I put it off for a long time trying to get a old Linde PCM-100 running well enough for me to do the little stainless jobs I do every now and then. But I had this big stainless job in the shop and the Linde let me down. I had to have a plasma right now to finish the job. I was planning on a Powermax 1000 knowing from past experience that I didn't want to go to small. But the LWS only had the one smaller or the 1250 in stock. So I sprung the extra money on the 1250 and haven't regretted it since.

And that's one of the many reasons I like the scarfing tip. Less chance of nicking the shaft. The only drawback to a scarfing tip is most of them consume a lot of O2.
Mike

If you cut across like I did with the nut then I find it easier to do than a scarfing tip myself. One of the tricks to that which I didn't mention in the video is to not mess around and get the shaft or bolt hot. Hit it quick before the bolt or shaft has time to heat up and it's much less likely to cut them. That's one of the reasons I nicked the threads on the back side of that nut. I messed around and took to long on that back cut letting the bolt get warmed up.

[irish fixit]

Ok finally managed to get two more uploaded. I was planning on starting these to upload and do some more but when I started this upload my computer got taken over by a trojan. It took me several hours to get it back up and running.

Anyway the first one covers piercing metal with a torch and the second is a close up of adjusting the torch. You still can't see the individual cones in the flame but maybe it'll be clearer for those wanting to see more on that.

[davec]

Impressive - Thanks Irish!

[irish fixit]

You're welcome. Hope the close up cleared up your questions.

[houseoffire]

Irish, Your the man! Thank you so much for sharing your skills.
I have absorbed a huge amount of info from these clips, really helpful for a newbie! Thanks again.

[irish fixit]

Irish, Your the man! Thank you so much for sharing your skills.
I have absorbed a huge amount of info from these clips, really helpful for a newbie! Thanks again.

You're welcome.

Here's another clip once it gets through uploading it's currently at 63% and it start over 3 hours ago so I'm putting this up now so I can get a shower and go to bed. I upped the camera to 720p so it would be HD. I'm hoping the upload goes smooth.

Anyway I'm afraid this one might be a little bit of a show off but it shows what can be done with a torch. It didn't go as smooth as I'd hoped but it's not bad. I did prep for this one. I ground all the rust and scale off both sides and preheated the piece before starting the video. I was using a low preheat on my good 1/4" tip with 40psi oxygen and 7psi acetylene and it's 1/2" plate. It was still hard to go fast enough to keep a good clean cut going so there's some slag on the bottom but not to bad considering the amount of cutting that was done.

You will have to give it time to finish uploading before you can see it.

[irish fixit]

Well looks like posting the link before allowing it to upload didn't let it embed. Here it is again.

[farmersamm]

don't need no steenkin' videos, just show the results



Geez!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[farmersamm]

See, the name would have been just as good without all the dark stuff that no one could see anyhow

[farmersamm]

BTW..............plasma don't cut it

[killdozerd11]

I think you went to dark with the filter for demo shots..can't see what your doing
other than that great video

[irish fixit]

don't need no steenkin' videos, just show the results



Geez!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

This is not for you sam. It's for those who don't know how to use a torch. Some things just can't be explained in pictures and words.

See, the name would have been just as good without all the dark stuff that no one could see anyhow

Yeah that one is to dark.

BTW..............plasma don't cut it

I has it's place you just have to have the ability to learn what it is.

I think you went to dark with the filter for demo shots..can't see what your doing
other than that great video

Yeah it's darker than I wanted. Actually that's the same filter I've used for all of them except one. The difference is that's it's wasn't sunny outside so my ambient light was lower not letting you see beyond the flame. I may have to reshoot this on on a sunny day.

[denrep]

Samm, you gotta lay off the sauce, Buddy.
Although the cut on the left looks a little better.

Yesterday I had a chance to toss my hat in the cutting ring.
I know this isn't exactly comparable, ‘cause I picked an extra-clean used plate to cut, and used another plate as a guide/steady rest.



Harris 62, propane, whatever tip was in it and whatever the pressures were set at before I picked up the torch - I can check.
West wind 5mph, 40 degrees ambient.



Smooth steady travel, with good height control, that's where it's at.
Nothing else matters as much. Not fine settings, not plate prep or condition.
I picked this nasty unprepared plate and used "whatever" settings and tip to underscore that torch control is the most important
factor in obtaining a decent cut.

Just like that dude cutting out his name shows. Good one Irish!


Good Luck

[daddy]

That is very nice, denrep! I struggle with rusty material. I can hack it off well enough, but a nice edge like that without grinding first... I need some practice.

[irish fixit]

Samm, you gotta lay off the sauce, Buddy.
Although the cut on the left looks a little better.

Yesterday I had a chance to toss my hat in the cutting ring.
I know this isn't exactly comparable, ‘cause I picked an extra-clean used plate to cut, and used another plate as a guide/steady rest.



Harris 62, propane, whatever tip was in it and whatever the pressures were set at before I picked up the torch - I can check.
West wind 5mph, 40 degrees ambient.



Smooth steady travel, with good height control, that's where it's at.
Nothing else matters as much. Not fine settings, not plate prep or condition.
I picked this nasty unprepared plate and used "whatever" settings and tip to underscore that torch control is the most important
factor in obtaining a decent cut.

Just like that dude cutting out his name shows. Good one Irish!


Good Luck

Good cut on lousy material there. Sometimes that can be hard especially if the rust is several layers deep. I've not managed to find any really bad plate to cut yet. That type stuff gets scrapped and the scrappers have cleaned up my scrap pile lately. I'm also looking for something good to show gouging on without success so far.

Thanks for the compliment. I'm in the process of uploading another name cutting with lighter filter and the sun out so maybe you can see what I'm doing. It's going to be a while though. It's at 20% and I started it 2 hours ago.

That is very nice, denrep! I struggle with rusty material. I can hack it off well enough, but a nice edge like that without grinding first... I need some practice.

Rusty metal usually needs a lot more preheat and slower travel speed to make it come out right. Also a pass across the plate with the preheat and oxygen blowing can help clear path for the cut.


Here's one I took this morning when I had to cut out a couple of lifting eyes for some welder skids I made. Notice I checked my freedom of movement and moved the hoses the first time and the shim the next. This is with a 1/4" rated tip in 1/2" x 4" strap. I was a little shakey this morning so it's not my best work.



[ame]http://www.youtube.com/watch?v=XvXBaRPObjw[/ame]

[weldbead]

Do they use the term "slag" in industry? What i mean is, is the term slag, when using o/a cutting, acceptable? i learned that the correct term is Dross. Just want to know if you guys use this term when talking about oxy acetelyne cutting. You only get "slag" if you are using flux...right?

technically both are classified as snots

[irish fixit]

Ok here it is guys (finally). Cutting out a name (and saving my bacon needed a present now for the wife who walked in during the cut but my hand headed her off). This time I cut the oxygen pressure down to 30 so I could go slower. Once again my good 1/4" tip cleaned up and working well.

[ame]http://www.youtube.com/watch?v=GKpOhiq28Wc[/ame]

[killdozerd11]

Excellent video Irish

Wish i was half that good