some oxyacy questions

[SE18]

Thanks, that's exactly what happened yesterday! They wanted to sell me a B tank AND a new regulator

They also told me I couldn't use a rosebud with my small setup. They said I need a new regulator and some kind of turbo torch that lets air in thru holes. That alone (no tank or anything) was nearly $400!

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On a different topic, it cost around $60 to exchange the tanks. If I'm doing 30 minutes of cutting and use up the fuel that comes out to $120 per hour to use the oxyacy gas. I'm thinking I need to cut my practice time down and get good really fast or spend a lot of money.

The reason it costs more (proportionately) to fill small tanks is b/c there's a handling fee involved on top of the gas/oxy fee.

I'm inclined to hang onto the small tanks even if someday I get large ones b/c if I find a nice piece of scrap (like an old Sherman tank) lying out in some field that I want to cut up for steel, the transportability factor will be there.

Thanks again for your suggestions.

 

[SE18]

I'll just use what I've got for now and dream about bigger tanks and more tips later on. So instead of a rosebed, maybe get a good bonfire going and throw the steel I want heated up into the flames and drag it out with a chain. Problem solved

I spent today mostly welding bits of metal then putting them in my vise and applying a sledge to see how the welds hold up.

I'm using a #2 tip for this and it works well for steel, both thermal and RG-45 rods if the work isn't too thin (it burns it up if too thin).

Steel that's high in carbon and more than about 5/16" thick I found hard to weld to other pieces of the same. Mild steel seems to be working well and steels moderate in carbon.

I think after twisting and test pounding welds, I'm ready to repair all my steel furniture in the house, maybe as early as tonight. It's pretty darned hot outside now.

 

[SE18]

two quik questions.

1. Can diecast be fused with steel?

2. so parts cool down quicker, is it OK to spray them from a distance with garden hose?

thanks

Hopefully I can post some photos of actual projects completed soon

 

[Codered741]

two quik questions.

1. Can diecast be fused with steel?

2. so parts cool down quicker, is it OK to spray them from a distance with garden hose?

thanks

Hopefully I can post some photos of actual projects completed soon

It depends on the material that the cast part is made of. Generally die cast parts are made of aluminum, Babbitt, zinc or some other low melting point material, so welding with steel is not an option. You could try to braze or solder them, but your success will really depends on what material you are dealing with.

If its cast iron, or steel, then there are ways to go about welding these parts. Cast aluminum may be weld able, but it it difficult to determine the alloy of aluminum without some testing. However these parts are not generally die cast.

Quenching parts, dunking them in water or spraying them with a hose, is generally not recommended. That is unless you are not worried about potential deformation, and hardening problems. When you rapidly cool metal, especially pieces that are heated unevenly, the rate of cooling in different areas can cause the part to warp. It also causes the material to become harder and more brittle, which is sometimes desired, but doing this intentionally is a complicated process, and spraying with a garden hose is not going to do it.

If you are just wanting to cool off test pieces, or something like that, spray away. If its a part that matters, avoid it.

NEVER quench a brazed joint though! The rapid cooling and the different thermal expansion rates of the different materials involved in a brazed joint can cause the joint to shatter, potentially sending chunks of hot brass at your face.
anic:

-Cody

 

[Ray C]

Can't answer #1 but for cooling with a garden hose, be apprised that quenching can make metal very hard and subsequent machining is harder (assuming you're doing machining). That's a lesson I learned the hard way.

Ray

two quik questions.

1. Can diecast be fused with steel?

2. so parts cool down quicker, is it OK to spray them from a distance with garden hose?

thanks

Hopefully I can post some photos of actual projects completed soon

 

[SE18]

 

[SE18]

guess my reply didn't make it (the text)

fixed a $30 trimmer that had snapped (the die-cast part). Fastened with nut/bolt/washer and brazed. burned some plastic in process that was holding the other end so added fastener there

it was the first time I'd ever brazed and went better than I could have imagined. used the white coated brazing rods designed for gas welding from Lowe's (Lincoln brand)

thanks for tips

this was my first project and hopefully there will be more I'll post

 

[SE18]

I just tried brazing some thin steel (duct). It works but seems you have to not dilly dally or burn hole thru it.

BTW, I'm wondering if I should save the oxyacy gas for cutting and welding and use the propane torch for brazing. Might make sense?

Also, I am thinking to eventually get a oxy/propane setup to save on some cost; either that or acquire bigger oxy acy tanks from somewhere.

 

[Codered741]

I just tried brazing some thin steel (duct). It works but seems you have to not dilly dally or burn hole thru it.

BTW, I'm wondering if I should save the oxyacy gas for cutting and welding and use the propane torch for brazing. Might make sense?

Also, I am thinking to eventually get a oxy/propane setup to save on some cost; either that or acquire bigger oxy acy tanks from somewhere.

If you are trying to save money, you need to look at what you will be doing more of, brazing or welding. I personally find that I do more cutting and welding than brazing. Therefore, I keep a large acetylene and oxygen tank on hand. I have a small mapp torch for everything else. If you are going to be doing LOTS of brazing, some cutting, and very little welding, the Oxy/Propane might be the way to go.

But cost wise, it doesn't seems practical to have both. Double the regulators, double the torches, hoses, tips, etc. A lot of cost just in startup.

IMHO, a good Oxy/Acetylene rig suits the needs of most hobbyists very well. I use my torch setup about 1-2 times a week, and only refill about every 6 months to a year. I have to refill the propane on the grill WAY more often!

-Cody

P.S. Looking good with the brazing! The carbon around the joint, and the fact that your thin material is melting, is indicative of too much heat. Try backing off with the torch a bit, you don't need that much heat for brazing. Heat the joint until its cherry red, and dip the brazing rod into the flame and the joint until it melts onto the joint. Once you have enough material, get rid of the rod, and let it cool. You should have a nice coating of flux covering the joint and most everything else, which you will need to clean off! Its a very slow process, until the brass begins to melt, then you have to move like crazy to finish the joint!

 

[SE18]

thanks, I might use my oxy/propelyne kit (the one no one likes after they buy it) for future brazing. I try to heat the larger metal more than the thinner so the thin doesn't cook off, btw

I plan to do more welding than anything else, but the portability of the oxyacy might come in handy for salvage cutting work, so I've got that in the back of my mind

although I love to use the oxyacy for welding, I'm beginning to wonder if I should simply pick up a cheap AC stick welding setup as the amount of fuel used for welding can seem to be rather expensive (unfortunately). I'm not into MIG at all, just don't care for it.