17 replies to this topic

[MetalMuncher]

Greetings!

Been a while since I have posted, but I'm back! I have been taking a serious interest in oil forges. I have all of the pieces for my burner, and testing will be underway soon. I chose the Moya oil burner design.

However, I really like the propane forge design. It resembles a piece of pipe layed on its side, with the burner entering at an angle from the top. I was wondering if I could use that same sort of design for my oil forge.

Heres my main question: Could I use a 1 foot section of 1/4 inch thick steel pipe for my oil forge? The diameter is about 7 inches or so.

Most oil forges/foundries I have seen were made of refractory cement. I dont want to use cement. The oil needs to be at its flash point before the burner can self sustain, and I think a metal forge shell would heat up quickly. I dont think that the heat would be wasted, even though the forge shell would release heat into the air. Any other forge/foundry would do the same.

Any suggestions, pointers, ideas, doe's or dont's, please feel free to chime in =]

Cheers dudes! Tell me what you think!

[ThomasPowers]

You would be throwing so much heat out from an unlined furnace that it would be nasty to work near and a combustion danger. It would also be extremely inefficient and you might have troubles reaching high temps with it---just think what the state of the wall will be if you are trying to have welding temps inside of it!

[MetalMuncher]

Hehehe, does sound kind of silly now that you put it like that Thomas... Well, I live in Brasil and refractory items are hard to come buy. When you CAN find them, they cost an arm or a leg. There is some low grade refractory cement, but it can only handle 400 Centigrade...about 800 F. I guess it would withstand higher temps than regular cement. I am now looking at Don Fogg's forge, looks pretty neat. I want to make something similar, but using bricks made with cement I mentioned. Any thoughts?

Cheers!!

[Mainely,Bob]

Whenever I`m confronted with a problem that seems to be unsolvable due to unavailable materials I always look for a local fix that I can use in place of the "best" stuff.
Don`t know where you are located within Brazil but a lot of the steel used up here is coming from Brazil so I know there are folks down there that use large quantities of refractory and that`s where I`d start to look as they may allow you access to their surplus.
The more urban areas will usually have companies or individuals who make things like pottery/ceramics and glass work.They also use a lot of high heat refractory product.

If you are in a very rural area then look to what the locals use to form their pottery and more importantly what they fire that pottery in and how.There may be a chance you could work with a local craftsman to have him help you make and fire a liner for your forge out of local materials.Any liner is better than none at all and if it doesn`t hold up long term you will know where to go to get a replacement.

[Phil Krankowski]

You can use ceramic clay such as kaolin. You can use firebrick. You can use vermiculite as a low density layer, but it will need protection from the highest heat.

If you are lucky you can dig some high temperature clay out of your back yard.

Phil

[MetalMuncher]

Hey Bob, thanks for the help. I live in Rio de Janeiro...but a further up a bit north there are serious metal working areas. Dont think I would even be able to get in though =[ I might have some luck looking for a ceramic potter. Great idea! Thanks!

Phil, where I was living before, there was some decent clay. But it tends to get all full of cracks after a few burns. Do you think it hold up better if I mixed it with regular cement?

Thanks a heap guys!

Cheers!

[Phil Krankowski]

I'm going to split this reply up, I keep getting interrupted and loose what I write.

Cement is a bad idea, it cures by absorbing water. At about 500F the water gets driven off causing the cement to crumble as the curing reaction is driven in reverse.

Your clay needs grog to reduce shrinkage.

I'll post another reply in a minute
Phil

[Phil Krankowski]

Clay requires grog to reduce shrinkage as it dries then cures. Clay uses water to separate the particles to allow molding. During drying the removal of water causes shrinkage. Next step is driving off bound molecular water. This also causes shrinkage. Lastly the clays recrystallize as they cure at temperature. In principal grog does not participate in this recrystallization, but gets trapped in the crystals.

Useful grogs are fired clay of the type you are using. You can also use clay of a higher temperature, but not a lower temperature. You can also use a "thermally inert" material like zircon flour, sold stateside as Zircopax or Superpax, among other names. For "free" you can crush an old toilet or some old junk china for high fire grog.

This is well on the line of pottery or brick making, and will require a means to fire the ceramic before installation so it is well cured. A basic high fire kiln will do this job just fine.

Phil

[MetalMuncher]

Hey Phil, thanks for your help!

I dont mind using grog furnaces for actual smelting and ore reducing, but I dont want to use it for my forge. I guess I will just go ahead and order some decent fire bricks.

One quick quesion about my Moya burner though...My oil feed pipe comes about 3 inches short of the end of the burner. Is that ok? Or does it have to go all the way to the end like the dude below made?

Thanks again for your help!

P.S- This is a Moya burner: http://home.comcast....moya034/burner/

http://home.comcast....ya_burner01.jpg

Cheers!

[metalmaster1766]

MetalMuncher,

I have built a burner similar to that one, well that's where I got the idea, anyhow I made a few changes as I used whatever I had on hand to build mine, but as for the oil line, I did however cut my oil tube to about 1-1/2 inches short of the burner tube/pipe and it works just fine.

Can you get a longer piece of tube/pipe ? if not then how about cutting a bit off the end of your burner tube/pipe, or try it as it is now being 3 inches short of the end and see how it works, then cut a bit off and try until it works.

Mine is adjustable and I could possibly move it so it is up inside the end by 3 inches and see how it works, but it may take me a few weeks to get all the stuff moved away from my forge as I have been reorganizing my workshop for the past few months.

Good luck, and it took me a few weeks of fiddling around with mine to get it to work properly, I tried gravity feed, then about 20 psi of air pressure, and that is where I have found it to work real good is with a bit of air pressure pushing the oil in, I preheat with propane and after about 5 minutes I start turning on the oil, once the oil is starting to burn I turn the oil up and the propane down until it is running on oil only. Another thing, if you can use flare fittings on all oil lines as they are less likely to leak over compression type fittings, which I only used temporarily until I could replace them with flared fittings, also buy a tubing flare kit.

If I can find my pictures and video's I will post them as well one day real soon.


Ron

[MattBower]

I built a very similar oil burner a few years ago, based on Colin Peck's design. I did not find gravity feed satisfactory, and you really need good fine control of the oil flow and the air -- finer than I had. But good golly, did it ever get hot when it was running right! Scary hot, really.

Knowing what I now know, father than build one of tehse I'd probably get a scrapped oil burner from a household furnace and outfit it with a waste oil nozzle.

[OddDuck]

The burner for my big metalcasting furnace is a Moya-style. Here's a pic:

It's a little dark but you can see the basics. Very effective, puts out prodigious amounts of heat. You will definately want a high temp liner or you will wind up with a forge full of molten goo. Skip the portland cement, stick with the purer clays like kaolin or 3000f+ rated commercial refractory. They can be tricky to start up, you need a good pre-heat for the oil to vaporize and ignite correctly. Otherwise you get billowing clouds of black smoke. You may want to add a propane pre-heat for ease of use. You will also need a pretty good blower, to compensate for backpressure and restriction of the burner tube.
Honestly, I don't think this is a great design for a forge burner, it can be difficult to control the atmosphere in the forge, and I don't think blowing oil droplets all over your metal will help the forging. I'm wondering if this is an application for a hot-box style burner, like Lionel Oliver's designs or mine, which is based on his.:

I call it the PBU (paint bucket ursutz), and it worked pretty well. It got surplanted by the Moya-style burners and is considered a generation or two back in the oil-burner tree, but would work well for this application, I think.
Just my two cents.

[MattBower]

Hey, OddDuck, nice to see another BYMCer here! (I'm a.k.a. Matt22191.) You, me and welder19 makes three that I know of.

One thing I've always wondered about the ursutz designs: does the fuel intake tend to coke up?

[metalmaster1766]

I am also a BYMC, I go by Ron Smith over there so that makes 4. I haven't been able to do much in either casting of forge work for the past year, but I do get a little bit done every now and then

Matt,
I built an ursutz type oil burner years ago and I had nothing but trouble with it, I tried a few different designs and I gave up on it after about 6 to 7 months of working on it


Ron

[OddDuck]

Old Home week for BYMC! I guess we know where the oil burner technology is, eh? Matt, I never had the PBU coke up, the fuel and air flow isn't conducive to that, however they can flood easily, and can be just as finicky as the Moya. I haven't used my last PBU build in over two years, as a matter of fact I pirated parts off it to build my Moya-style. The oil injection is in the setup right above the floor flange attached to the top of the paint can. Here's a pic of it:

Worked quite well, I set it up with my small furnace and got it to blinding white in about five minutes, so they can definately put out the heat. I think that a forge application, along with a kiln setup or a reverb setup would be the niche for an ursutz. Now I've got to pull it out and experiment with it. Great. Another project.

[metalmaster1766]

Sorry for hijacking your thread metalmuncher, I'll try to make it short and add a picture of my oil fired forge

OddDuck,
I like the idea of using the flange that way and adapting it to a reverb, I think I have a few of those flanges of different sizes laying around, when I get my newest forge finished I'm gonna hafta start experimenting on an oil burning reverb.

here is a link to my newest construction, gonna line the inside with fire brick having a 3 inch wall thickness and a 10 inch inside diameter, gonna be oil fired as well. I'll start a new thread on this when I get back to working on it.

http://i28.photobuck...rgeForge-01.jpg




and here is my oil burning forge with propane preheat and it did run only on propane before this year

http://i28.photobuck...oilburner-1.jpg







Ron

[MetalMuncher]

Hey guys, thanks for the tips. No worries about "hijacking" my topic hahaha.

I made my moya burner (shame I dont have any pics) and I gave it a go. I preheated with wood and I used old motor oil and it put out some good flames. It heated a piece of half inch rebar to a light orange heat.....I am looking for yellow.

Two things might have caused this: I made a rather stone age-ish forge to try it out. It was just a pile of bricks with the burner coming in from the side. It wound up facing a brick dead on, but I wanted to fire it up anyway. It was a simple forge, so I didnt bother angling the burner....I am pretty sure thats why it didnt get ever so hot.

Secondly, it was a pretty sunny day so I might have not been able to percieve the colors all that well.

My next try will be with veggie oil...lets see how that goes.

What do you guys think? Thanks again!

Cheers!

[MattBower]

Sunlight will completely wreck your perception of steel color. Try it again with some shade. A properly tuned oil burner will get HOT.