$500.00 or offer ...

CH701 Rear is done, I have some parts for forward.. I also have a 4 x 12 bench on wheels. Name the price.. It has to go..

Hey Chris, Have you started building yet? I have a rear fusealge and some forward peices I need to move. I just sold my house and can not take it with me. If you are interested or know someone, let me know. Thanks, Rick Jennings

IHi Chris;
I have scratch built a 701 and am flying it behind a Firewall Forward Cam125.
I am contemplating scratch building a 750 and am considering a WW Corvair setup (probably a 3100).
I was wondering if you have any info as to the preformance figures as to a 750 with a Corvair.


PS. Scratch building is a lot of fun and not All that difficult. and the metal is really not all that expensive.
Jerry Shepard in WI

























firewall Forward Cam125.

Or if you meant "how hard was the CNC set up" for the parts for the 650...

If you are plans building, you will ultimately have to measure and draw out all the cut lines on a sheet of aluminum. My day job as an engineer provides me with the experience to draw this all out on CAD much faster than I could by hand. If I didn't have a CNC, I would draw out and plot what I needed to cut, glue that paper down on the sheet of aluminum, and then cut and drill. So either drawing it on the aluminum by hand or on a computer first and futzing around with the paper template is about the same time wise.

Generating the CNC's cut file takes a bit of additional time but cutting it on the CNC is faster than by hand. If I only had to make one airplane, it'll take the same time with a CNC as it would by hand... but the cnc makes nice straight lines and drills perfectly spaced rivet holes.

Also, the plans are set up for someone making it by hand. Now that I've fabricated the ribs, they could be done much faster if the design changed to optomize for a CNC operation (such as cutting all the lightening holes first and adding other construction holes, cutting the flange into tabs as opposed to crimping, and pre-drilling all the rivet holes).

Forgive me, but I can take your questions two ways and so I'll answer it twice.

The CNC took me a few months to build. I used my own design, but it's a combination of standard construction practices from several types of machines (Digital Tool, Shopbot, etc.). The table is made from steel, it's got V-wheels and track on all axis, and the X and Y axis are driven by gear track and an Acme screw on the Z. It's got stepper motors, the drivers are Gecko drivers in a power cabinet from the internet, I'm using the free Mach-3 version, and programming the code with a REALLY OLD version of Bobcad (DOS version!)). I was using a router but quickly upgraded to a 3HP Elte spindle and a VFD (the bearings are much better and I have speed control from 100 to 18,000 RPM). If I had to guess I would say I have about:
$500 in the welded steel table,
$1500 in the V-track, V-wheels, gear track, and miscellaneous hardware,
$1000 in the stepper motors, drivers, power cabinet, and wiring,
$0 in the PC, Mach-3, and Bobcad,
$2000 in the spindle and VFD.

I sold it all Chris. I was making what I could and buying what I couldn't. If I decide to go with the CH701, I'll have to start all over. With all the lay-offs lately and more to come, I may just sit tight for a while.

Richard J.
Alderwood Manor, WA.