Lightest weight O320

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Pops

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Are you using the GPU crank with the prop flange reinforcement or the 320 crank ?
 

cluttonfred

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Even if the 3D printed material is not strong enough to use as a final product, it can be used to create a model for casting aluminum. That might work for you and is much cheaper than 3D printed metal these days.

is then cast as this


If you mean printing useing a plastic fillament,then probably no.
If you are refering to 3D printing useing laser sintered titanium,then probably yes.
 

dog

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Dec 29, 2019
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Even if the 3D printed material is not strong enough to use as a final product, it can be used to create a model for casting aluminum. That might work for you and is much cheaper than 3D printed metal these days.

is then cast as this
Very very nice.
I have cast a little in my shop,(lost wax,bronze)
and spent a few days in an old time foundry helping a friend.
I can realy see how ,cad to 3d printing could help
bring work to smaller foundries, as the skills involved in traditional pattern making are lost now.
The old foundry was still doing the odd pour ,with
the one of there projects bieng a solar furnace that they actualy melted bronze with.Huge thing with a mass of fressnel lenses and mirrors.
 

rv7charlie

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Nov 17, 2014
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Jackson
Yes, you can build a (cheater) 320 using a 290 D2 case with the cylinder holes bored out 1/4" (not 1/8"). I've done that. Two things: It has to be a D2 case, not a D or G because you need hydraulic lifters which the D and G do not have. Wide deck cylinders won't bolt on, only narrow deck ones. Some of the airboat guys use 290 G (narrow flange) crankshafts to save 3 pounds. I believe that the G crankshafts are actually 235 crankshafts. I have a rebuilt G C/S if you're interested. For building a carbon sump you need to use special hi temp epoxy of course. When you paint, only 1/2 the weight of the paint stays on whatever you're painting. The other half is lost through evaporation and out the exhaust fan.
If by 'G' you mean the ground power unit crank, the flange needs to be reinforced even in the O290, when it's installed in an a/c. I'd be really leery about it if the plane is going to do acro.

Charlie
 

Toobuilder

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I have a spare IO-360 that is earmarked for a minimalist Pitts that I don't own yet. My weight saving scheme is a fabricated oil sump, SDS rocker covers, a single SDS CPI brain driving 2 coils, and an SD-8 alternator to power the ignition. I do have SDS EFI on my Rocket, and while it is lighter than the mechanical FI, the added complexity of the electrical system makes it a tough sell for a weight saving scheme on a minimalist biplane. I haven't weighed the FLYEFI stuff, but considering it's a rip-off of SDS, I'm guessing the weights are similar.

Sump.jpg

Cool thing about the CPI: It displays RPM, Voltage, and MP, so you don't need those instruments in your panel. Even more weight savings.

Ignition.jpg
 
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