Backyard Foundry - oil burning furnace - moulding and casting a spider

Interesting posts about different fuels,I built my first furnace nearly 50 yrs ago with my late father,[& burnt a few out since!!] the only information for an amateur [like me] was B.Terry Aspins "bible" foundrywork for the amateur, no internet then, with folk casting alloy wearing flip flops & shorts & pouring it into tart tins & getting loads of praise on their apparent skills, as Luker says [& I really enjoyed his articles & also learned a few things from him!!] there's various ways to build a furnace, when I started I built mine to run on coke with a blower, as per B.T.A. 50 yrs on I'm still on coke poss because we always have a couple of tons in for our rayburn cooker but as said above it's getting more difficult to get coke now with demise of the steelworks,I did build a small propane furnace powered by my flamefast torch & it's really good but having inherited a large amount of central heating oil along with the central heating burner I might try that, propane is really expensive, of course you can get re-fillable bottles & it's much more cheaper at the forecourts.

Graham.

The running joke in our house is that anyone who looks over the wall and complains about someone casting metal should rethink their strategy. At least the person casting has a hobby and doesn’t get up to mischief. Seriously though, I live in a city suburb and have asked all my neighbours if the furnace makes a noise and they all said it does not. I have a large box covering the blower (this makes most of the noise) with inverted egg boxes glued to the inside which dampens most of the noise. The furnace itself isn’t too noisy.

Hi Luker I must look at your oil fired burner seeing as how i inherited gallons of oil from my late father in laws central heating tank, next door. luckily I live in a village & we have a large back yard so noise isn't an issue & we're not in a smokeless zone , the good thing about coke furnaces is they're quiet, I use a bouncy castle blower with a home made restricter disk on the inlet, no electronic gizmo to go wrong, in fact when I'm fully glowing the inlets almost closed so the motors doing hardly any work in fact it's using less electric!! btw I've mixed up some of your additive for melting fine turnings, I'll be trying it this week. as I have some nameplates to cast for his loco .

Graham.

Thanks, Luker. Unfortunately, I live in the city proper. Small city lot and exposed to neighbors on all sides, no fences. If I lived in the suburbs I would have much less concern. My next door neighbor has complained about a lot of things, including me parking my car in the *public* street in front on her house. I suspect she would think I *was* up to mischief with a casting furnace. Some people take the hint when being ignored, others unfortunately don't. From the videos I've seen, the burner has a pretty big roar even without the blower. No?

Thanks Graham. There's a few more I've submitted to ME about casting, from methoding to furnace linings, and alternative-simpler alloys from base metal scrap for the model engineering. I hope you guys find them interesting!

If you're melting brass fines rather pour them into ingots, you might end up with too much super-heat. Gunmetal and the bronzes work a little better when pouring directly into moulds from fines.

Yep please give it a go and let us know how the burner works for you.

Yep it does... I would guess its similar to a vacuum cleaner.

Thanks for the info Luker I'll let you know how I get on.

Graham.

There is a fellow in the Pacific Northwest who build an iron furnace, and his neighbor complained about the noise.

He added a six foot sheet metal chimney that is lined with ceramic blanket, and installed that over his lid opening, and build a box for his combustion air blower.

He verified a very low dB with an inexpensive measuring unit.

My neighbors have not complained (yet) about my furnace, but I do live next to an expressway, and the dB level from cars and trucks passing is absurd already in my back yard.

One trick I have used is to place small sections of rubber floor mat under each wheel of my furnace, and this takes out a lot of the low frequency rumble that many hear.

An oil burner and furnace is basically acting like a V1 pulsajet, and thus the noise created, plus the blower noise.

At some point soon I will move my blower indoors, and stretch a hose out to the furnace, to eliminate that noise.

I have excess combustion air, and so the pressure drop across a long hose is not a problem.

If an oil burner is tuned correctly, and especially if it is operating on diesel, it should start cleanly, and operate with no smoke at all. It should not produce any smoke upon shutdown either. In some of my videos, you can see what looks like a lot of smoke, but it is actually steam from water that has crept into my ceramic blanket.

I keep my furnace outdoors at all time.

A muffler stack is an option, but uncoated ceramic blanket in the exhaust stream will produce fibers that you do not want to inhale.

Here is the fellow with the muffler stack.

Be sure you have some outriggers on your furnace if you crane out your crucible like this, because it is easy to flip over your entire rig with a crucible full of iron.

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For a simple gas furnace see, dubious engineering - melting brass in a spindrier, You will see me and my mobile foundry in operation ! Enjoy. Noel

Hi Luker, lit the furnace today, [coke fired] & cast 2 nameplates & 2 number plates in brass for a friends little boy [6 yr 0ld] for his 5" battery loco he built for him, patterns made from mdf cut out on a fretsaw, I had small turnings chrome plated brass bath taps few plumbing fittings & few old steam rally plaques,,Put a tablespoon of your additive in the crucible & the brass cast really well, no porosity lovely castings, cleaned up well, very little if any zinc loss I always keep a lid on my crucibles & coat tools,skimmers pyrometer probe etc in contact with the metal with zircon based refractory wash also ingot moulds & tart tins as well as you will know molten alloys corrode steel as well as poss contaminating the melt, did you put details of your oil burner in model engineer? I'm interested in building one & like the sound of it ,thanks.

Graham.

Hi Graham, that's great news! Thanks for the feedback. I'm always glad when someone can take something I've written about and reproduce the results, then I know I'm sharing knowledge and not just boasting .

Yep my furnace design, including the burner, is in ME4626. I gave the ratios of what will work based on my calculations, but my actual sizes are also given.

Please let me know how you get along!

PS have you got some pics of the name plates?

Hi Luker, thank you for that info, [embarrassed now as I have the back numbers of ME, & should have looked,!!] I've taken some photo's of the melt & the furnace in action & have just been fettling the castings up today I'm etch priming then paint with traditional red background I've polished the letters but I'll have to get my son to print them in here as I don't know how to, he should be up this week sometime once again thanks for your help, photo's to follow.

Graham.

Hi Graham Ladle wash will help to reduce cross contamination from one metal to another, though the level of contamination will be so small as to make little difference. Whilst the heat will accelerate corrosion The real matter is that of molten metals dissolving one into another, even when the solid metals melting point is way above that of the molten metal. Noel.

Hi Noel, thanks for that info, when I started work at the local high school one of the first things I did was get the unused flamefast crucible furnace up & running I had no ingot moulds so I poured surplus alloy into large jam tin till it was semi-hard then tipped it out into crucible sized lumps all ok for a few melts till one day the bottom fell out!!! after that I made moulds & got refractory wash. hehe .I'll look at your " melting brass in a spin drier"

Graham.

Your neighbours will complain if you are in close proximity. If you are experimenting it may produce a lot of smoke and noise. Try propane fuel but i have had success with solid fuel ie. blacksmiths nuggets and anthrocite with a small blower, very quiet, when running right no annoyance.

Thanks Dave.

Hi
Luker, [son came up & loaded up for me!! thanks Philip] a few pictures of my set up 1st one showing the drag with the patterns removed,2nd one the "pot fodder" bath taps rally plaques plumbing fittings etc,3rd one moulding boxes ready to pour 4th one shakeout & lastly the finished castings for the little lads loco fettled polished acid etch primed & 2 coats of 2k suzuki red.

Oops, added more pictures & got details mixed up!!1 & 2 ok 3 first lighting up with wood4 moulding boxes ready to pour 5 pre warming brass on top of crucible with more on the top of the lid 6 ready for lift out 7shake out & finished castings!

Hi Graham, the name plates look great! Surface looks spotless and they polished and painted beautifully. Thanks for the pictures.