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jes / 3d-metal-printing

Notes and information about 3d metal printing
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Attempt 7: puzzle part, aluminium, lost PLA #9

Open jes opened 4 years ago

jes commented 4 years ago

Pour the plaster, leave it to sit until it is solidified, then try this temperature profile:

  1. Ramp 150 2h00m
  2. Hold 3h00m
  3. Ramp 400 4h00m
  4. Ramp 700 2h00m
  5. Hold 1h00m
  6. Heater off

Idea here is that we have it spend a significantly longer time at lower temperatures, to dry out the plaster gently and stop it from cracking. And we don't need such a high max. temperature if we're only melting aluminium.

jes commented 4 years ago

Scaled up 2% in all axes

jes commented 4 years ago

I put it in the plaster approx 1500 BST, and I've programmed in the temperature profile.

Will put it in the furnace first thing tomorrow. Need to remember to flip the flask upside down.

jes commented 4 years ago

The furnace is almost reliable enough that I'd be comfortable letting it run unsupervised overnight.

jes commented 4 years ago

Got impatient so I'm switching it on this evening. Switched on ~2030 BST.

jes commented 4 years ago

The plaster didn't crack, and this is the closest to "working" that I've had so far, but it's a bloody awful casting.

image

jes commented 4 years ago

Final dimensions (relative to printed part) are:

Outside diameter: 38.2mm (-4%) Inside diameter: 24.9mm (-4.5%) Height: 21.4mm (-2%)

Also, based on its volume and density, we'd expect an aluminium object of this size to weigh 34g and it only weighs 29g. And the one I turned on the lathe weighs 34g. I think there might be quite a lot of porosity in this.

jes commented 4 years ago

Apart from where the mould split in #8, the casting is arguably much higher quality in that one than this one, which is a surprise.

Maybe brass is easier to cast? Maybe because it is denser?

Waynewaynehello commented 3 years ago

This is actually a pretty good attempt in my opinion, and might look better after polishing. Maybe not for strong parts, but at least for models (silly 3D printed stuff).