Model Engine Maker
Supporting => Casting => Topic started by: A7er on September 25, 2022, 02:41:50 PM
-
I decided to re-design my flywheel and conrod, they will both be seen on the finished model. I am also using matchplates for most of my castings now. The patterns for the parts were 3D printed on my Ender3. The new filament I am using sands very easily and I can get a good surface finish with very little filling. The matchplate for the flywheel has a sump at the bottom of the sprue, I included this feature to see if it would catch any loose sand. The picture of the cast flywheel shows the sump and a band of red sand around the bottom, it did catch sand that could have ended up ruining the casting. There is some flashing on the conrod, my sand was a little dry, but very little on the flywheel. I think the flywheel pattern needs a bit more sanding around the rim to make extraction from the sand cleaner. Perhaps a coat of gloss paint would help?
Both parts are cast in ZL12 alloy.
Lee
Edit.
Whoops! I forgot to mention sizes. The flywheel is 90mm dia and the conrod is 90mm long.
-
Looks like you have found a winning combination (not saying that you can't improve further :noidea: )
The Castings appears to be very good and usefull :ThumbsUp:
Per
-
Nice work.
I did a an investment cast recently using Polycast filament. I know you're not burning out, but two things about it are noteworthy; its about the easiest and nicest printing filament I've used and more germane, it can smoothed with an IPA mist. They sell a misting chamber, the price imo is a silly, but its got me thinking....what I can hobble together that will do the same thing. Some of the results on the net are fantastic, although no idea how much retouching was involved. The filament itself was not premium priced, about the same as any IPA.
-
Thanks Per, I aim to do better!
Mcgyver. If my memory serves, I watched a video a year or two ago posted by Josef Prusa about using acetone in a metal or ceramic dish in a sealed box with the pla print, the fumes affect to pla to smooth it out. I think the timing is critical. It should be an easy video to find.
-
I don't think acetone will affect PLA, its used for ABS to smooth....but ABS is a harder material to print and a mist of acetone seems nastier than using alcohol
-
PLA in pure form doesn't react to acetone, only if your particular brand has other ingredients that make it react. ABS does react to acetone.
-
Very tidy patterns
Results look awesome
-
Those look slick, nice work, and very clean looking castings! If I had the inclination, I'd make a hacksaw/bandsaw cut through the sump to see if the sand stays at the bottom.
-
I've made 3 of this type of flywheel now (1 failed because I didn't melt enough metal), each has the sand in the same place. I will cut one tomorrow to have a look.
I am now preparing the patterns for the cylinder head. Casting soon......
-
Good luck! :cheers:
-
I got so tied up with gardening then work on the patterns for the cylinder head I forgot cutting the sump.