Thorp Air Command - T18.net

That is just so cool, Bruce! I'm surprised it works so well with aluminum considering all the wood in the structure - usually you have to have a rock-solid metal structure to maintain accuracy and finish of the cut. I'm sure that using the small diameter end mills helps and makes it doable. Was it difficult to learn the programming, or did you already have experience with that? I'm curious - what was the cost of the motors and other parts from China? Again... nice job!

_________________
John Evens
Arvada, Colorado
T-18 N71JE (sold)
Kitfox 7 SS N27JE

John,
Dec 2013 the 3-axis electronics, which included 3 425 oz motors, 3 motor drivers, power supply and parallel port break out board was $199, other companies had packages for $390. The fan, power connector and switch were donated from a bad computer power supply. I had the plywood and a router motor. All of the other pieces, hardware, roller chain, sprockets, couplers, wire, etc, etc, etc was about $600. I used cross dowels and 1/4" machine screws to assemble the gantry structure.

The finish is not as smooth as it could be most likely do to the flexing of the machine, also I need to check all of the screws to see if any need to be tightened now that I have some run time on the machine. If I had not messed up one of the mount holes it would be a usable part.

The finish on softer materials is quite acceptable, i.e. wood and pink foam.

For my next try, I'm redoing the program to take a smaller finish cut at a slower speed.

_________________
Bruce Finney
N18JF T-18C #262
Yelm, WA USA

Finally got my version of the Air Dog DIY remote oil filter adapter installed.


The adapter started life as a 3"x3.25"x1.0" block of aluminum. I had a couple of blocks donated by Scott Emery and Gary Jacobsen out of their respective scrape bins. See previous posts in this topic on using a CNC router to make the adapter. Air Wolf wanted $350 for just the adapter.

The hoses are Earl's Perform-O-Flex with Earl's Swivel-Seal hose ends and Flame Guard insulation, the stainless band clamps are Harbor Freight stainless cable ties at $0.25 each. The cost of the hoses was about $250 for 2 -8 hoses for the oil filter and 2 -6 hoses for the oil cooler. The 90 deg -8 fittings were $25 each, the good news the fittings are reusable. The firewall mounted oil filter mount from Summit Racing was $25. I'm using a K&N oil filter, I forgot to shoot a photo of the filter mount today.

I moved the airplane out of the hangar this afternoon into a late winter snow storm, snow was sticking to the grass not to the pavement, to do a engine run to check for leaks, none found, I'm a happy camper, now I need some good weather to do a flight test.

I'm actually looking forward to my next oil change and not having to mesh with that darn oil screen.

_________________
Bruce Finney
N18JF T-18C #262
Yelm, WA USA

that looks sharp Bruce. Nice looking work.

Bruce my man ! That's some pretty fancy metal whittling !

RB

Ah shucks Rich, it twern't nothin

_________________
Bruce Finney
N18JF T-18C #262
Yelm, WA USA

Here's a shot of my remote filter mount.

_________________
Bruce Finney
N18JF T-18C #262
Yelm, WA USA

Gotta ask. What is the lawn mower gas filter for?

_________________
Bob Highley
N711SH
SN 835
KLAL

It smooths out the manifold pressure to my Dynon engine monitor

_________________
Bruce Finney
N18JF T-18C #262
Yelm, WA USA

Is it really pressure or a vacuum ? Most builders put a fitting that has a small orfice to eliminate the pulsing

Thanks. I just pounded a rivet in the fitting and drilled it out with a #80 drill.

_________________
Bob Highley
N711SH
SN 835
KLAL

Bill,
It depends on what your reference is, if you measure as a reduction of atmospheric then call it vacuum, if you measure relative to 0 then it's pressure. On aircraft we measure pressure, on cars vacuum. When the engine is not running the manifold pressure is the same as atmospheric, standard day = 29.92 inHg. If the gauge read zero with the engine off then it would be called vacuum.

I also have a screw with a #50 hole in one end of the filter unit. The filter acts as a reservoir and also keeps any gunk that might get in the line from getting to the pressure sensor.

_________________
Bruce Finney
N18JF T-18C #262
Yelm, WA USA

There's pressure change, but no real "flow" to that sensor to bring any potential "gunk" into it. A properly sized orifice is all that should be needed to smooth out pulsation. The filter does add a couple more connections and takes up a little precious space back there though. The filter mount looks good Bruce.

_________________
John Evens
Arvada, Colorado
T-18 N71JE (sold)
Kitfox 7 SS N27JE

Dang, that's a good idea. I probably paid $25 for a reduced orifice fitting.....

I'll take the filter ! I might be able to use it on my espresso machine !

RB