home made forge

[Derek cottissParticipant @derekcottiss41883]

[Derek cottissParticipant @derekcottiss41883]

hi

i have another hobby which involves the need to melt and cast lead as well as a pile of copper aluminium and brass so i need a forge (or want)

I get the idea of building one but i want to run it from waste oil .

So will it produce enough heat from vaporised waste engine oil and has anyone tried it ?

cheers

[Les Jones 1Participant @lesjones1]

I have made a waste oil burner for my furnace using a Hago Delavan syphon nozzle.
This is a link to the design of my burner but you will find some other designs on the web.
This is a link to the blower system I used.

Les.

[Derek cottissParticipant @derekcottiss41883]

Posted by Les Jones 1 on 01/01/2021 10:47:37:

I have made a waste oil burner for my furnace using a Hago Delavan syphon nozzle.
This is a link to the design of my burner but you will find some other designs on the web.
This is a link to the blower system I used.

Les.

what sort of presure do you use to vaporise the oil ? and i take it it burns clean ?

[SillyOldDufferModerator @sillyoldduffer]

Oil is the best fuel available and engine oil is no exception. Plenty of heat in it but it's not easy to burn efficiently. To maximise heat and minimise nasty side effects it's necessary to use a burner as described by Les. The burner controls the mix of fuel and air for optimum results. Otherwise, engine oil is difficult to ignite and liable to incomplete combustion producing clouds of thick smoke, likely toxic, and not much heat.

Lead is easily melted (368°C), but Copper, Aluminium and Brass need about three times the temperature. Copper 1084°C, Aluminium 450 to 700°C depending on the Alloy, and Brass 900°C to 1100°C again depending on the alloy. All within reach. Cast-iron and steel require even more heat, and an improved design.

Outdoor job, well ventilated, not for pregnant ladies. Get lead much too hot and off come poisonous fumes. Molten brass loses Zinc, altering the properties of the metal and a serious health hazard if done on a large scale or in a confined space. Brass founders usually add Zinc back to replace that lost during the melt, but for amateur purposes the exact composition may not matter. Aluminium is safe enough, but if melting scrap don't mistake Magnesium for Aluminium. Magnesium is much more likely to catch fire than most metals and it explodes if water is used to put it out!

A potential problem with home melted scrap is the unpredictable output. Alloys vary considerably depending on exactly what's in them. Cartridge Brass is different from Plumbing Brass which is different from Hard Brass. For making rough castings and ornaments it probably won't matter, but expect trouble if anything high-tech is attempted, like machining.

Can you report back when you get it working? It's an interesting subject.

Dave

[John HaineParticipant @johnhaine32865]

Do you want a forge, or a furnace? A forge sounds very inefficient for melting metal. Also burning waste engine oil is likely to be very polluting with the various additives from petrol and their degradation products let alone the CO2.

The excellent Mike Cox describes a furnace for melting metals here that uses propane – much more environmentally friendly (and neighbour friendly too I suspect).

[Derek cottissParticipant @derekcottiss41883]

Posted by John Haine on 01/01/2021 11:39:13:

Do you want a forge, or a furnace? A forge sounds very inefficient for melting metal. Also burning waste engine oil is likely to be very polluting with the various additives from petrol and their degradation products let alone the CO2.

The excellent Mike Cox describes a furnace for melting metals here that uses propane – much more environmentally friendly (and neighbour friendly too I suspect).

You could be right that design would probably be better as for the waste oil burning versus propane re emisions i can measure the exhaust content to a point so will have a look into it and compare the differences ,Wate oil is currently burnt in heaters once vaporised at acceptable levels though

[Derek cottissParticipant @derekcottiss41883]

Posted by SillyOldDuffer on 01/01/2021 11:31:37:

Oil is the best fuel available and engine oil is no exception. Plenty of heat in it but it's not easy to burn efficiently. To maximise heat and minimise nasty side effects it's necessary to use a burner as described by Les. The burner controls the mix of fuel and air for optimum results. Otherwise, engine oil is difficult to ignite and liable to incomplete combustion producing clouds of thick smoke, likely toxic, and not much heat.

Lead is easily melted (368°C), but Copper, Aluminium and Brass need about three times the temperature. Copper 1084°C, Aluminium 450 to 700°C depending on the Alloy, and Brass 900°C to 1100°C again depending on the alloy. All within reach. Cast-iron and steel require even more heat, and an improved design.

Outdoor job, well ventilated, not for pregnant ladies. Get lead much too hot and off come poisonous fumes. Molten brass loses Zinc, altering the properties of the metal and a serious health hazard if done on a large scale or in a confined space. Brass founders usually add Zinc back to replace that lost during the melt, but for amateur purposes the exact composition may not matter. Aluminium is safe enough, but if melting scrap don't mistake Magnesium for Aluminium. Magnesium is much more likely to catch fire than most metals and it explodes if water is used to put it out!

A potential problem with home melted scrap is the unpredictable output. Alloys vary considerably depending on exactly what's in them. Cartridge Brass is different from Plumbing Brass which is different from Hard Brass. For making rough castings and ornaments it probably won't matter, but expect trouble if anything high-tech is attempted, like machining.

Can you report back when you get it working? It's an interesting subject.

Dave

i see lead and scrap aluminium being the main candidates although turning cartridge cases into something that doesnt look like cartridge cases would make them acceptable to the scrap dealers

[Les Jones 1Participant @lesjones1]

Hi Derek,
I can't remember the exact air pressure I use but I think is is only about 20 PSI. The nozzle is designed to suck up the oil but I use gravity feed to get a greater flow. I also heat the oil to about 100 degrees C so it atomises better. (The oil is not vaporised in the nozzle. it comes out as a fine mist. I use the water heater part of an old steam press to heat the oil. I start the burner with propane as the oil mist is not easy to ignite. Once started it burns without smoke. (But it is quite noisy.) I had to buy the nozzle from the US as I could not find a stockist in the UK.

Les.

[Engine BuilderParticipant @enginebuilder]

Let's get the terminology right, it's a furnace that melts metal, a blacksmith would use a forge.

This waste oil burner uses a low cost nozzle..

 

Edited By Engine Builder on 01/01/2021 12:54:27

Edited By JasonB on 07/01/2021 10:53:19

[noel shelleyParticipant @noelshelley55608]

An excellent source of nozzles is Mig welder contact tips. For oil firing an old central heating oil burner can provide almost all you need. Propane is clean, easy and viable cost wise as a fuel for all but cast iron. As for the air pressure it will be under 5 PSI. Noel.

[Derek cottissParticipant @derekcottiss41883]

Posted by Engine Builder on 01/01/2021 12:52:36:

Let's get the terminology right, it's a furnace that melts metal, a blacksmith would use a forge.

This waste oil burner uses a low cost nozzle..

 

Edited By Engine Builder on 01/01/2021 12:54:27

 

 

yep my mistake thats the clip that got me thinking you can get most of that burner online for about £30

Edited By JasonB on 07/01/2021 10:53:31

[Jeff DaymanParticipant @jeffdayman43397]

Myfordboy on youtube designed and made a nice oil burner for his melting furnace. Made his own 3D printed blower to go with it, as well. Lots of good casting videos there too. Worth a look.

[not done it yetParticipant @notdoneityet]

Sorry to say, but most modern-day cartridge cases will be magnetic, so probably hard luck on that one. Caps may be brass, at least on the outside. Many bullet cases will be brass, but not checked any recently.

[Derek cottissParticipant @derekcottiss41883]

Posted by not done it yet on 01/01/2021 14:31:43:

Sorry to say, but most modern-day cartridge cases will be magnetic, so probably hard luck on that one. Caps may be brass, at least on the outside. Many bullet cases will be brass, but not checked any recently.

Shotgun cartridge cases yes rifle cartridges cases are normally brass the bullet goes in the case normally lead but copper is being introduced for some game shooting ..

[Derek cottissParticipant @derekcottiss41883]

[Derek cottissParticipant @derekcottiss41883]

So after having this bottle for over 20 years , Calor didnt want it back the valve put up a serious fight until the cutting wheel on the angle grinder came out that is . Current thought is to cut the top off (creating a lid ) and remove the centre section to create a flue . Any thoughts ?

[BazyleParticipant @bazyle]

What diameter is it? Mike's in the link earlier is 12in dia.
Mike seems to use portland cement as the key binder. I have seen a comment elsewhere that that is less optimum as it decomposes at a relatively low temperature (perhaps wrt cast iron not AL) on the other hand I've seen a recommendation for plaster of paris which in theory is definately low temp yet that caster used it for several years for AL. Then I see 'castable refactory' cement advertised intended for differnet temperatures (and cost) from 1300C to 1700C.
Lots of choices; lots of different youtube videos.

[Derek cottissParticipant @derekcottiss41883]

Interesting hour on the phone with Noel last night , more questions to think about i think .

Yes it is 12 inch diameter im thinking maybe ceramic blanket but not sure if this needs a 'hardener '

more research i guess

[Ady1Participant @ady1]

A long time ago in an internet galaxy far far away I recall reading the website of a chap who was taking the microwave route for smelting

He was heading up past 800 degrees C at the time, maybe his site is still out there if you search about

Here's a simple one but the more serious guys are definitely out there

[Derek cottissParticipant @derekcottiss41883]

Posted by Ady1 on 08/01/2021 14:06:01:

A long time ago in an internet galaxy far far away I recall reading the website of a chap who was taking the microwave route for smelting

He was heading up past 800 degrees C at the time, maybe his site is still out there if you search about

Here's a simple one but the more serious guys are definitely out there

guess he had to change his trousers

[noel shelleyParticipant @noelshelley55608]

Microwave or induction ? One may run as high as 5Kv the other about 50v !

[Adrian R2Participant @adrianr2]

I made this last year as my son wanted to try some metal casting. It's a composite of several internet designs, starting with an out of ticket butane cylinder similar to yours. Cutting done with angle grinder disk and plasma cutter (after filling with water and thorough rinsing to remove any gas remnants), base is an old firebrick, lining is the non-hazardous biosoluble blanket, and it's fired with propane using a burner salvaged from a space heater.

We've melted and cast alumimum (easy) and copper to make aluminium bronze (harder, but turned out machinable), works fine except that if you run it too long the tip of the burner gets red hot and then it starts misfiring so improving that is waiting for the proverbial round tuit to arrive.

Updated – I realised this was a work-in-progress photo – I later added some handles to it as well to make it easier to move. The lid is a tilt and swivel which stops it reflecting heat back at you when opened – inspired by FarmCraft101 on Youtube for that part.

 

Edited By Adrian R2 on 08/01/2021 18:20:18

[Oily RagParticipant @oilyrag]

I have a friend who is a Farrier by trade, and as a lot of his business is 'mobile' he has made a forge similar to the Calor gas bottle but inverted the cut top to form a bowl. He multi drilled air holes liberally around the valve area and runs it on coke with a remote air blowerr driven by a 12V motor/fan assembly. He 'kick starts' it with an air bottle at higher pressure topped up from his home based compressor. Keeps it in his van between jobs and says it keeps him jolly warm in the winter months. But the point here is he uses it as a forge for hoss shoeing, we are going to give it a go at melting some scrap aluminium to see if it is capable, I don't see why a coke fired forge would not get hot enough to melt some aluminium in a suitable crucible buried into the coke fire.

Martin

[Adrian R2Participant @adrianr2]

Alternatively for model engineer scale stuff, have a look at the electric furnace being used by Myford Boy to make Nigel Taylor's lamp post engine. Seems a lot more efficient and less hassle for home workshop use.

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