Casting jewellery


#162

i do my best curing . I do my best
you can do your best casting in the way as you want.
Just to do the best for this moment


#163

we could give it a try… where are you located?


#164

hello everyone,
last week sent out some prints to test again.
I have just received casted pieces in 14k gold and silver
result for me is satisfied. I like it :smiley:
what do you think? there are no wholes for overwelding


bubble is better than a whole :smiley:

I am happy with result of post-curing and casting

Also they (casting company) do not know Formlabs’ burnout schedule.
They just casted as they always do.

thanks
Peter


#165

So they didn’t burnout for 14 hours? The long burnout is making me want to create wax models from Form prints that burn out more quickly.


#166

Hi Kat
No they don’t use 14h burnout schedule. I am sure.
I asked them once about some change of temp, so I was told that they would not change anything just because one person had brought them a print. Becuase it woule be risky of all orders they received.
So they casted as ussually they do.


#167

I don’t burnout for 14 hours.

All temps are degrees ‘C’

Flasks in kiln @ room temp (it’s 8 degrees in my workshop today!)

Ramp from room temp to 167 degrees in 1 hour

Dwell 30 minutes

Ramp @150 degree/hour to 732 degrees (usually takes 4 hours for my kiln)

Dwell 3 hours

Ramp 100 degree/hour to 630 degrees

Dwell 4 hours - I wait at least 1 hour into the dwell then cast, so usually 9.5 hours for 1st cast.

Small squares on grid are 1cm - Ring is size N - Cast, cleaned with ultrasound bath, then pickled to de-oxidise

Casting resin 02 @ 0.1mm

Some defects but nothing too drastic, I need a curing box, my LED strips are fading.

Dougie


#168

so just send me your file when you want.
thx


#169

looks and sounds good :slight_smile:


#170

@digitalDougie
hi Dougie
do you cure just with LED stripes? a ring looks nice. good job

how much time does it take to cure your way?


#171

@digitalDougie, THANK YOU!!!

Translated for the (idiotic) American imperial system…I’m an America so I can say that:
Segment 1: Ramp 260°F per hour, arrive at 330°, hold 30 minutes (assuming 74°F starting temp)
Segment 2: Ramp 300°F per hour, arrive at 1350°F, hold 3 hours
Segment 3: Ramp 100°F per hour down to 1165°F, hold 4 hours, wait at least one hour until casting (is that correct?)

I’ll give that a try! digitalDougie, what investment are you using? And I’m assuming that’s sterling silver? I usually have the last hold at a lower temperature, but I’ll try your higher temp just for fun. :slight_smile:


#172

That looks right, they are sterling silver.

I use an investment from SRS I mix at 400ml per Kg (2.2lbs) and melt my metal in graphite crucibles, no flux.

We have a similar vacuum machine and I find that the higher flask temp assists metal flow, I protect my silicon casting rings with a graphite ring, I get those from eBay but I think Rio Grande do them, I think they also do a woven casting ring that can handle the higher temp.

It took me a while to get the burnout schedule right, my kiln is quite old and the elements are a bit slow, adjust the ramp rate temps to fit the times if your kiln is quicker/slower, I think the 9.5 hours is long enough though.

Good luck with it.

PS, I have used Castaldo VLT to mould castable resin but have also used their high temp pre cut rubber to mould cured castable parts, both worked well.


#173

Hi Peter

Yes, I am using a chamber based on the one that @Randy_Cohen shared with the forum although I have an upturned egg incubator sitting on my jar blowing in air @ 45 degrees ‘C’ (it can’t go higher).

I have recently had issues with dimming LED’s though so am going to get a nail dryer similar to the one in the Formlabs video. I cure for around 8 hours, sometimes more, it depends on the time I have between printing and casting.

Dougie


#174

do you use from time to time formlab’s burnout schedule?


#175

My experiments began with the Formlabs schedule, it’s just been adjusted to suit my kiln.


#176

This is not true on so many levels. Not all 3d printers leave striations on the surface. I’ve seen many that print super smooth surfaces and cast like wax. Like envisiontechs, dws, and solus. Have had samples printed on all of them, and they were perfect.


#177

@David_Maillot
hi David,

I send your design post-cured to test after weekend,
pls send me addres on my priv

thanks


#178

I have also cast samples from envisiontec, and many others. I have not yet seen a 3D printer that does not produce striations on the surface. Agreed some of the expensive machines are superficially smooth but if you use a lens you can clearly see the striations even on the most expensive machines. the exception is the T66 and T76 which use wax droplets and with a lens you can see the surface is made of droplets.


#179

The Carbon can print at 1 micron layers. All we need to do the same on the Form is a semi-permeable CLIP vat window and firmware to support it.


#180

A friend had his Roland 3D printer software modified so that it would print in any layer thickness from 1 micron and found that it was pointless to go so fine as it just extends the print time without improving the quality of the surface. The total voxel size is important to surface quality and that includes x and y as well as z. I find that 25 Microns for Z is usually fine and that the real problem is not the printer resolution but getting the V2 resin to burn out cleanly without destroying the internal surface of the plaster mould in the process.


#181

I can’t really comment on the Roland because I don’t know enough about it. But just because it was set to print at 1-micron doesn’t mean it actually will. The hardware has to be capable of working at that resolution.

With CLIP, it can print at 1 micron and still print over 10 times faster than the Form can currently print at 50 microns. There is no peel or wipe process that slows things way down. Instead, the laser is working continuously.

I am not suggesting one could print 1-micron features and have them cast. But if you look at that link I sent, the striations are practically non-existent even in the microscopic view - which is what I thought we were discussing. :wink: