Metal Melter

[Onoff]

Light grey, RS PRO PLA printed at 0.1mm layers. I would say markedly better, quality wise, than the fibre silk brass effect PLA. Certainly around the ears / overhangs. I'm not even sure tbh if he used supports it's that clean (I was in bed when it was printing).

I was tempted to give it a dusting over with a primer / filler spray to fill in the odd pinhole. Thinking not, they might come out looking like age marks in the brass.

A single ice cream cone printing now. Then the triple cone job, then the PVA female which I'm oddly excited about trying...

 

[Kram]

Looks good. I was reading about PLA smoothing, it seems DCM is the only accessible chemical to effectively do it, unless your PLA is one of the odd modified versions. To use, part is steamed with dcm vapours.

Infill - light as possible for burnout, Id imagine would be best.

Melter control box lid

Will reassemble it later.

I was tempted to give it a dusting over with a primer / filler spray to fill in the odd pinhole. Thinking not, they might come out looking like age marks in the brass.

Use wax for any print defects. I dont think the pin holes will look good. Better to patina it afterwards..

 

[Onoff]

If my lad thinks the cow took some doing then wait until he hears my next mental idea for a horse brass. The North Downs Way near the pub is famed for its bluebells.

Multiple, probably macro shots of a bluebell, then photogrammetry to make the solid. It's going to drive him nuts but he'll thank me later! I love the idea of a moment in time immortalised forever.

Guessing ceramic dipping might be better but where's the fun in that?

 

[Onoff]

You've just anodised the lid? That's attention to detail...

Will have to reprint these then with a lighter infill unless you're happy to try what we've done? Too light and they become very flexible.

 

[Onoff]

Honestly I was only searching for pictures of bluebells...I wonder if she'd nip down to give my lad some encouragement in his endeavours?

Bluebell Availability for May... - Casting call - PurplePort.com

Check out my casting on PurplePort!

purpleport.com

 

[Kram]

Will have to reprint these then with a lighter infill unless you're happy to try what we've done? Too light and they become very flexible.

It will be fine. It may even be better. I'll try it... get it in the post Ive not yet tried burning out plastics so guess work until then.
Landlords can be pain with anything that smells but I think pla should be quite clean burning?

 

[Kram]

You've just anodised the lid? That's attention to detail...

Most of the box is mild steel.. I guess the front cover should be done too.. right I'll set that up now.

 

[Onoff]

It will be fine. It may even be better. I'll try it... get it in the post Ive not yet tried burning out plastics so guess work until then.
Landlords can be pain with anything that smells but I think pla should be quite clean burning?

Seriously I'm happy to drop off (I know where you live! )

Not looking for an invite or anything just thinking the prints and half this investment powder will weigh a few kilos.

If delivering might even be able to bring wax models if the PVA mould idea works.

As an aside what dia steel cylinder do I need to make a furnace and must it have a bottom? I've a length of 197.3mm OD CHS. Too small?

 

[Onoff]

These PLA prints are done at 20% but using Cura's "lightning" print option. Makes for faster printing and uses a varying density support - shown orange. Not then much more than a shell in places:

 

[Kram]

Forgot about this thread... I was replying when I dropped my phone and broke the screen

Seriously I'm happy to drop off (I know where you live! )

Not looking for an invite or anything just thinking the prints and half this investment powder will weigh a few kilos.

If delivering might even be able to bring wax models if the PVA mould idea works.

I can not lift my storage box theres now so much melting stuff - and the furnace is in the one below!

If you want to drop it here thats ok or I can do a hermes collection. The prints alone should fit in a rm "large letter" for a pound, if its under inch thick?

As an aside what dia steel cylinder do I need to make a furnace and must it have a bottom? I've a length of 197.3mm OD CHS. Too small?

200mm with 150 bore is under 25mm wall for lining and no insulation. Without insulation your limited to aluminium temperatures and that may be difficult. 300mm gives the extra 50mm insulation. It would work for 75mm bore, with the tall cruicibles that chinese melters seem to use but too small for burning out patterns.

Having a bottom helps, you can be sure its not going to fall through.

 

[Onoff]

If you want to drop it here thats ok or I can do a hermes collection. The prints alone should fit in a rm "large letter" for a pound, if its under inch thick?

Ta. It was mainly for the powder and if we do a PVA print(s).

Quite like the idea of being stopped on the M23 with 2.5kg of unknown white powder. Might get a night in the cells and a decent breakfast!

 

[Onoff]

The old moving target conundrum! Printing the PVA female here and though the support structure is super stringy, the inside face of the mould is really quite good, even down to the "hollow" for the horns:

 

[Kram]

Almost assembled. You may have heard me swearing, when I realised I' d glued the power meter without giving clearance for the steel case that slots inside the lid. I have chopped some of the plastic off.

 

[Onoff]

Got the thumbs up from the landlady as to the cow model!

Cow mould in PVA. Came out better than we thought!

 

[Onoff]

Meant to say that the top left "rectangle" piece, came off as I was cleaning the PVA mould up. Should be easy enough I guess to stuck back on with PVA glue. You can see the hollow inner of the mould.

 

[Onoff]

Ordered some casting wax with a 52degC melting point:

Scarva Wax Scopas Red Modelling Wax | Scarva.com

Contains natural beeswax, paraffin wax and resin. Specially blended for modelling and cire perdue. May be softened or hardened by adding more parafin wax or resin. Melting Point: 52°C £13.88.| Fast P & P.

www.scarva.com

Now then, to keep it at 52degC I'm figuring one of those pots ladies use for depilatory wax. On the look out for a cheap one with digital readout. Like this:

 

[Onoff]

@Kram , ref the comments you and @DAPPH made over on the over thread ref retaining the element etc. Appreciate my lad's PLA former is sitting there ready for the MK2 one day but us there any milage in PVA?

We print a copy of the actual clay mould in PVA. In effect a cylinder with a recessed, hooked groove in its walls. We then fill with hot poured, red casting wax. Soak and let the PVA dissolve. We're then left with a hard wax former for the clay to wrap around.

Just thinking out loud

Is the clay poured or hand moulded?

Not sure when done how easy it'd be to push the element around the spiral?

 

[Onoff]

@Kram I was going to decant some of this investment plaster into large coffee jars for you. You ok with that?

 

[Kram]

Forgot to reply The pva mould looks great!

@Kram , ref the comments you and @DAPPH made over on the over thread ref retaining the element etc. Appreciate my lad's PLA former is sitting there ready for the MK2 one day but us there any milage in PVA?

We print a copy of the actual clay mould in PVA. In effect a cylinder with a recessed, hooked groove in its walls. We then fill with hot poured, red casting wax. Soak and let the PVA dissolve. We're then left with a hard wax former for the clay to wrap around.

Just thinking out loud

Is the clay poured or hand moulded?

Not sure when done how easy it'd be to push the element around the spiral?

It'd take a huge amount of pva and wax so I doubt it'd be economical. I think the pva former yousent is perfect I just need a round tuit. Clay is moulded.

With the good weather I have been getting out much earlier and getting more done, so I will try this week!

@Kram I was going to decant some of this investment plaster into large coffee jars for you. You ok with that?

Great, thanks!

 

[DAPPH]

Cat people, where can I get bentonite clay cat litter? Wilko list it, annoyingly no stock. Looks like everywhere sells wood pellet or paper types. Catsan is lime and sand, so no good.

Bentonite aka fullers earth cat litter . go to pets at home buy a big £12.50 of clay litter . . I used a free cycle food processor to take a mug of it down in hte big bowl to almost dust . then put it througha very fine sieve to get the powder . over several days i procerssed two sacks of it . next step was to liquify it . started off witht e food processor and a mug of water thn trickled powder in toill it was a thick soup and decaanted it into a lidded plastic bucket , carried on doing this till I'd got a bucket full , lidded it , left it over night then poured it into my very very clean cement mixer and ran it for half an hour . Adding a few more cups of powder every few minutes till it was a nice thick mix that readily stood in peaks when some was troweled out .
scooped it out a few trowels at a time and added more powdered litter till it felt very slightly gritty , left it over night and it was like a very crumbly thick cake mix that was readily pushed into the mould. I forgot to dust the forms and cope & drag copiously with baby bum talcum powder in a coarse cotton bag so the first time I tried to lift the form out the mould some of the medium stuck to the form .

Second attempt was good , got the breathers & spruce in then found out my melter was totally useless as it was not burning all the gas passing thorough the home made burner jet I couldn't melt the aluminium in a month of Sundays . . Gave up as a day or so later I got covid again and still haven't progressed much .


Kram the limestone in that cat litter might be too gritty .