When using a acetone vapor bath should you see the acetone percolated a little bit, just a small little boil?
Nah, you don’t even need that. Slight heat. Warm at most. If you actually ‘boil’ it, you probably have too much.
That’s why i run out so fast,ha. This rice cooker i have has 2 settings, cook and warm. Warm is still to warm then.
@ThantiK That depend on the size of your jar. I find that if I don’t boil the acetone, the acetone vapor doesn’t get more than about half way to the top of my 2 gallon jar. This is tested both by sticking my hand in and feeling the vapor and by putting a print in and seeing only the bottom half being smoothed. The cause is probably the thermal mass of the glass cooling the vapor and causing it to precipitate back down. I have to pre-heat this jar for at least an hour on a spare platform heater to get the vapor to go to the top.
Once your vapor starts do you keep the heat on?
In a 2 gallon glass jar with lots of thermal mass and low thermal conductivity, I do. In a rice cooker, probably not, though you might have to turn it back on periodically to reheat if you’re doing a lot of smoothing (a long session on one item, or sequential sessions on many items).
Thank You
Oh, @Wayne_Friedt a trick for keeping the acetone in the rice cooker is to cool the lid in your freezer, then take it out and put it on the rice cooker when you put the acetone in. The acetone will cool and circulate back down instead of going over the edge or out the pressure spout when in comes in contact with the frozen lid.
I insulated a metal baby formula tin so the tins walls get hot too. I leave to top 20_30mm uninsulated to ensure the vapour doesn’t spill over the edge. Also, try cooling the part in the freezer before hand: significantly increases the condensation rate of the vapour.
Yeah, putting the part in the freezer helps, just don’t try to do multiple smoothing sessions going between freezer and vapor bath to quickly, or you can cause the print to crack (not along layer lines).
Yea i tried the frozen lid trick and it did indeed keep the vapors from escaping from under the rim of the lid. Just now learned about parts in the freezer, i will try that next. My one part is a 10 fingered thing for an Iron man reactor and one finger bent down from being soft. i was able to stand it back up and it reattached as it dried out. It can also warp arts, yes i did and you need a flooring that has small holes cuz the part will form to the large hole if they are there…
@Wayne_Friedt you can avoid the sagging you mentioned by doing several short exposures with a drying period in between.
Ah good idea, didn’t know it would collectively add together. Thanks
Smoothing it repeatedly does smooth it more, but the results are not the same as one long smoothing session. Generally, multiple short smoothing sessions (with proper drying between) keeps the part more true to the original shape. It smooths small features more while leaving large features unaffected, while one long smoothing section will smooth (or otherwise deform) larger features. The ideal time for each session depends on the model detail and layer height, though mechanical parts that require dimensional accuracy should only be smoothed in very short sessions, if at all.
Ya i see now, some of my parts don’t fit together anymore. I am thinking maybe they will shrink back some when completely cured. If not they will need trimmed to fit. I don’t think these parts i did really look better. Yes they are shinny but the parts still have lines here and there and just don’t quite look the same. i will get a camera here in a bit and see if i can capture what i am talking about.
@Wayne_Friedt sounds exactly like my first experimentation with AVS; I just completely nuked the part that I had printed. It happened to be Big Mac from My Little Pony; he turned out looking like a shiny red blob of indistinguishable plastic with 4 legs and a head…thing…
@ThantiK How do they turn out now, better? You have the hang of it now?
Maybe a 2 gallon glass jar doesn’t heat up like a rice cooker does so the parts don’t warp as much. This thing i have keeps quite warm inside.
@Wayne_Friedt yeah, I only played with it a little more after that, but I was getting it down. At one point I was simply putting a glass jar on my heated bed and heating it up to about 40C-50C IIRC. I wasn’t leaving the parts in for long at that point, I just did multiple “dips”…never did the freezer thing.
My smoothing station results are very much different after about the 3rd or 4th time using it. I can see the change in the parts clearer now and have been regulating the temp by unplugging the rice cooker after i see it start to boil. Then just leave it for 10 minutes or so the plug in again. The parts actually are looking pretty good. Not as smooth as they are shinny. These are delicate parts so over smoothing is a disasters.