- Joined
- Mar 14, 2013
- Messages
- 443
Here are two things I made for my Fisher FP-404 biplane. The first is an oil separator... the 2 cylinder opposed engine has such large variations in crankcase pressure that it pushes a lot of oil out the breather, which ends up on the underside of the fuselage if it's not captured. When I bought the plane, it had a "puke bottle" on the breather, but too much vapor still found its way outside; I had to wipe it down after every flight.
I was limited by the lack of a lathe, but where there's a will there's a way. The tube (2" OD aluminum) was easy, just face it off in the mill. The endcaps fit over the tube with an o-ring in the groove, which I made with a holesaw. I then roughed out the outercircle with a bandsaw, chucked it up on a bolt in a collet in the mill, and turned the OD with a cutter in the mill vise. The fittings are aluminum, too, I cut the pipe threads short, tapped the pipe threads in the tube, and use JB Weld epoxy to secure them (welding would have been better, but I have no way to weld aluminum).
The lower fitting connects to the engine breather, which has a check valve so gases only go out of the engine. There's a copper "chore boy" scouring pad in the lower part, coalesces the oil out of the vapors so it drips down. Above the divider, the upper fitting vents clean air overboard. At the very bottom, a much smaller fitting is the outlet for the coalesced liquid oil, which returns to the engine via the small line, with another check valve letting the liquid in. It works quite well, and has significantly reduced my oil consumption.
The second project was a new tailwheel. The plane's original tailwheel was serviceable but ugly... it looked like (and no doubt was) an ordinary caster wheel that somebody welded arms to and drilled a bunch of holes in attempting to make it lighter.
I looked at a few commercially made wheels, but everything was overkill, overpriced, or out of stock, so I made my own from some aluminum angle, a 4" scooter wheel, and a Delrin pivot block and a steel bushing for the pivot. Looks better, works better, and will be featured in an article in the March 2017 issue of Kitplanes magazine (there's also an article about the 6 month process of restoring the plane to flying status in the February issue). They want an article on the separator, too, but I didn't take any good photos while making so I'd have to make another one to get the photos... they'll pay, so we'll see.
I was limited by the lack of a lathe, but where there's a will there's a way. The tube (2" OD aluminum) was easy, just face it off in the mill. The endcaps fit over the tube with an o-ring in the groove, which I made with a holesaw. I then roughed out the outercircle with a bandsaw, chucked it up on a bolt in a collet in the mill, and turned the OD with a cutter in the mill vise. The fittings are aluminum, too, I cut the pipe threads short, tapped the pipe threads in the tube, and use JB Weld epoxy to secure them (welding would have been better, but I have no way to weld aluminum).
The lower fitting connects to the engine breather, which has a check valve so gases only go out of the engine. There's a copper "chore boy" scouring pad in the lower part, coalesces the oil out of the vapors so it drips down. Above the divider, the upper fitting vents clean air overboard. At the very bottom, a much smaller fitting is the outlet for the coalesced liquid oil, which returns to the engine via the small line, with another check valve letting the liquid in. It works quite well, and has significantly reduced my oil consumption.
The second project was a new tailwheel. The plane's original tailwheel was serviceable but ugly... it looked like (and no doubt was) an ordinary caster wheel that somebody welded arms to and drilled a bunch of holes in attempting to make it lighter.
I looked at a few commercially made wheels, but everything was overkill, overpriced, or out of stock, so I made my own from some aluminum angle, a 4" scooter wheel, and a Delrin pivot block and a steel bushing for the pivot. Looks better, works better, and will be featured in an article in the March 2017 issue of Kitplanes magazine (there's also an article about the 6 month process of restoring the plane to flying status in the February issue). They want an article on the separator, too, but I didn't take any good photos while making so I'd have to make another one to get the photos... they'll pay, so we'll see.