Metal Melter

[prepman]

You're welcome to have a crack at it. I could send you one already printed? Saying that we haven't yet printed the final, "final" PLA one.

Ah....so it's the negative I saw? Or an stl image?

 

[Onoff]

I mean dip/paint the positives in investment plaster, to burn out, then and pour brass into.

What orientation would I have the positive, vertical, flat, face down?

Is dipping consistency for the plaster different to encasing consistency?

I presume I need to incorporate a "cone" with a hole in for pouring the brass? Any tips? Could print something that could clip/glue to the positive.

 

[prepman]

Trying to work out out why I've got an oozing nozzle.....thought it was just old age...but I'll try with maximum retraction at > 8mm and lower extruder temp further....but to no avail so far.
stl test file attached not mine...v'scan as I'm on linux almost bullet proof.

 

[Kram]

I presume I need to incorporate a "cone" with a hole in for pouring the brass? Any tips? Could print something that could clip/glue to the positive.

No cones unless you want it to come out a mess, just a hole in the back or open back is fine, the supporting structure/feeder will be in sand.

 

[Kram]

Didn't know you could dip in investment plaster!

Thought you had to bury/encase the model.

Possibly wants to be thicker than the ceramic people use. It will likely have some cracks when drying. 1cm wall should be good. If you use too thick it will take an age to burn.

 

[Onoff]

No cones unless you want it to come out a mess, just a hole in the back or open back is fine, the supporting structure/feeder will be in sand.

Again, surely you can't pour brass into PLA?

 

[Kram]

Noo that would be a mess Pla> plaster> burnout> brass

 

[Onoff]

Noo that would be a mess Pla> plaster> burnout> brass

I was more thinking a paper thin PLA shell that gets vapourised or whatever by the brass going in.

Or again a slightly oversized shell you plaster dip, coating inside and out surfaces.

Ignore my mad musings!

 

[Kram]

Other day playing with wax to make a back on tig torch holder.

Needs some adjustment. Going to thin it about half, leave enough to take threads. Might try 6082 aluminium, as then I might be able to anodise it. Im not sure how well that casts.

 

[prepman]

Refractory looks brilliant, very pleased and it's good for (1,700C) way in excess of the temps I'll be going to.


Will tidy it up lid and put a catch on the swing mechanism that will stop it lowering when not in the centre position. Simple pin and gate like this.


Crucible didn't fare so well. The underside..

 

[Kram]

What happened to the crucible? Heat too fast?

 

[Onoff]

On the way back from the pub just now...

A couple of gas cylinders on the adjacent farm's junk pile, destined for the scrap man. No idea what "kg" they are, but I can likely have them both:

The "grey" one, nom 1030mm circumference:

& 18" / 450mm high:

& then a "red" one. Nom 450mm / 18" high:

Nom 1070mm circumference:

I presume these will be suitable?

 

[Kram]

Should be, 300mm diameter, same as mine.
Mine was taller but I cut a section out, so those look about right.

 

[Onoff]

Should be, 300mm diameter, same as mine.
Mine was taller but I cut a section out, so those look about right.

Let me know the height of yours to the apex of the dome if you would.

Some photos of your one that I took today:

Crucible:

Hole / mounting for the thermocouple up and to the right of where my finger is sat, see the two button head cap screws:

 

[Kram]

Ok tomorrow will measure. I think the melter is 300-400mm high and the lid about 100mm.

 

[prepman]

Just had to order 3 x 47kg propane refills at £88 e@
Calor up £13 ea
There are cheaper gas companies around but the hassle with cylinders isn't worth it. Did that years ago. Calor has firmly clenched my gonads.

 

[prepman]

What happened to the crucible? Heat too fast?

Borax....No not a typo Old one used and abused. Stuck to old furnace floor. But all tend to craze.

 

[Onoff]

Just had to order 3 x 47kg propane refills at £88 e@
Calor up £13 ea
There are cheaper gas companies around but the hassle with cylinders isn't worth it. Did that years ago. Calor has firmly clenched my gonads.

I'd planned on a leccy element like @Kram but given the unit price of that I might have to build a bio-gas plant!

(I'm not kidding)

 

[prepman]

I'd planned on a leccy element like @Kram but given the unit price of that I might have to build a bio-gas plant!

(I'm not kidding)

Don't rely on EU funding....... Although 2nd to Ukraine in Eurovision is a major acheivement for us now. Most likely drive Putin to Nuke us?

 

[Anguz]

Can you use heating oil or is it too dirty?
I have a commercial heater burner sitting here