CNC Waterjet cutting instrument holes

On Thursday, February 26, 2015 at 1:09:53 PM UTC-8, wrote:
...7725 bid cloth that I had lying around (a decent cloth, but surely not what Schempp Hirth used)...

I have yet to find anybody who, when presented with unlabeled samples of Hexcell 7725 and Interglas 92125, can tell them apart.

As for the instrument panel cutouts, I am firmly in the holesaw camp--the carbide grit blades are great for that. I get a fair bit of stuff waterjet and laser cut, but only where it is the most cost- or time-effective method. For a round cutout and four screw holes, a good holesaw plus a template from the Schreder library makes it a five-minute job.

Thanks, Bob K.
https://www.facebook.com/pages/HP-24...t/200931354951

Thanks, Bob K.

On Thursday, February 26, 2015 at 7:11:05 PM UTC-8, Bob Kuykendall wrote:
As for the instrument panel cutouts, I am firmly in the holesaw camp--the carbide grit blades are great for that. I get a fair bit of stuff waterjet and laser cut, but only where it is the most cost- or time-effective method. For a round cutout and four screw holes, a good holesaw plus a template from the Schreder library makes it a five-minute job.

Thanks, Bob K.

I laser cut an acrylic template off an AutoCAD file that I'd created and used a template router bit to make the panel. All the holes were good to around two thousandths of an inch - which is what I needed because everything was pretty tight.

9B

On Thursday, February 26, 2015 at 12:06:01 PM UTC-8, wrote:
Hey All,
Does anybody have any experience with getting a fiberglass instrument panel CNC cut with a waterjet (or any other CNC cutter for that matter)? I called several local shops and I couldn't get a definitive answer whether the waterjet will delaminate the composite around the cut holes or not.
I've previously cut with bi metal hole saws and the hole turned out quite a bit too large and I trust a robot to measure a lot more accurately than myself. I was also interested in laser CNC cutting, but I'm pretty sure that will burn the composite around the edges of the cuts.
Any input would be appreciated.

Thanks,
Omri

Holes saws are very inexpensive at Home Depot. 2 1/4" 57mm, 3 1/8" 80mm.

Use these instruction to draw the hole on the fiberglass panel. Center punch and be very accurate. Pilot drill with a small drill and then drill mounting holes and large instrument hole. Fiberglass cuts like butter. Use a drill press and plywood for backing drill from the back of the panel.

Instructions to make the perfect hole.

http://www.craggyaero.com/Drawings/I...0Templates.pdf


Richard
www.craggyaero.com

Hey All, I ended up having it CNC routed by a machine shop named AST Waterjet (they do CNC routing too) in Grand Prairie, Tx (in the Dallas area). Cost me $195 which was their shop minimum. It turned out really well, no delamination around the edges. I had them drill the 4 screw holes around each instrument undersized and I reamed the holes up by hand with a drill press after. Every hole lined up perfectly so I didn't need to oversize any of those screw holes which was nice from a hole edge clearance point of view and since some instruments used 3mm screws, some 3.5mm and some 6-32. Turned out nicer than I could ever imagine doing by hand and probably saved me a lot more than $200 of my time. Did a full trail fit of all instruments, switches and everything yesterday and it all fit well, I'm spraying primer on the panel later on today.

On Monday, March 30, 2015 at 11:02:51 AM UTC-7, wrote:
Hey All, I ended up having it CNC routed by a machine shop named AST Waterjet (they do CNC routing too) in Grand Prairie, Tx (in the Dallas area). Cost me $195 which was their shop minimum. It turned out really well, no delamination around the edges. I had them drill the 4 screw holes around each instrument undersized and I reamed the holes up by hand with a drill press after. Every hole lined up perfectly so I didn't need to oversize any of those screw holes which was nice from a hole edge clearance point of view and since some instruments used 3mm screws, some 3.5mm and some 6-32. Turned out nicer than I could ever imagine doing by hand and probably saved me a lot more than $200 of my time. Did a full trail fit of all instruments, switches and everything yesterday and it all fit well, I'm spraying primer on the panel later on today.

Great news. Thanks for the update & have a good flying season.

Craig
7Q