Mailing List flyrotary@lancaironline.net Message #64565
From: Charlie England ceengland7@gmail.com <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: 3D printing - Oil inlet
Date: Sun, 6 Jan 2019 15:46:39 -0600
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Boy, how I wish I had the CAD chops to do stuff like that. I have access to a really nice lab full of 3D printers at our local community college, and no ability to create the drawings.

Have you checked air flow through the oil cooler (yarn on a stick)  with the exit assy off? I'd bet on very little flow through the two corners next to the inlet, based on what I saw in my duct with a similar expansion rate. Maybe you have a better internal shape than I was able to achieve with my sandpaper. :-) I used turning vanes to get more or less even flow across the whole core. The tight pinch at the back matches what I found I needed.

Charlie

On 1/6/2019 2:52 PM, Bobby J. Hughes bhughes@qnsi.net wrote:
Nice looking work Matt. You might consider doubling the size of the inlet to 30% of the core face. You may get by with less but it’s easier to fly and reduce the inlet / outlet than chase high oil temps that makes your Phase 1 more difficult. I made that mistake more than once :)


Bobby 



Sent from my iPad

On Jan 6, 2019, at 12:26 PM, Matt Boiteau mattboiteau@gmail.com <flyrotary@lancaironline.net> wrote:

Buying a 3D printer has opened up this whole experimental plane game. SO much easier to autocad a drawing, then trying to fiberglass out of foam and bondo. Bonus is, easy to make changes for version 1, 2, 3, ... 15.


I'm using an CX racing oil cooler. 30 Row, 11 x 9 X 2

To create a Kays & London wedge shape for the inlet, I could of used a flat stock and called it a day. But really it's an 'S' shape to maximize equal amount of air to flow across the rad. Plus I had to make the wedge shape, turn into an 2.75" pipe opening for the scat hose. I wanted to keep the bends like a trumpet, to maximize the air sticking and following the sides without disturbance. Could of sanded and shaped the pieces out of foam for days and days.. Or punch them into autocad. 3D print the parts, then fiberglass overtop of the molds.

The last two pictures (oil4 & oil5) are how I had to make the outlet, with foam and bondo. I couldn't get good measurements around all the pipes and motormounts, so I couldn't 3D draw it. Was easier this way, to build it in place. Took 10x longer to build.

The outlet has a large 5" box to catch the expanded hot air. Then it necks it back down to a 2.75" outlet pipe. The idea is the speed the air back up before it exits. I also added a butterfly valve to the outlet, to be able to control the temps. This should help fine tune my system (inlet, outlet, exhaust, cowl air exit), by watching how much the valve needs to more to keep temps stable at different flight speeds.

- Matt Boiteau
<oil1.JPG>
<oil2.JPG>
<oil5.JPG>
<oil4.JPG>
<oil3.JPG>




Avast logo

This email has been checked for viruses by Avast antivirus software.
www.avast.com


Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster