RivetBangers.com

gsimatos · Class E Joined: 19 Oct 2006 Posts: 182

Anyone aware of a supplier for a number 27 plexiglass drill bit for drilling the canopy holes?? Thanks Gary

bullojm1 · Posted: Tue Nov 18, 2008 6:07 am Post subject:

Gary-

Why do you need #27 plexi bits? If you read the instructions carefully, it tells you to enlarge the holes in the plexi to 5/32" (which avery sells a bit for). The reason behind making the hole bigger than a #27 is to allow the canopy to expand and contract with heat. I think Van's thinks theres a possibility for cracks to occur if you don't oversize the hole.
_________________
Mike Bullock
http://www.rvplane.com
RV-7 | Superior IO-360 | Whirlwind 200RV
Garmin 430W | GRT Dual Sport EFIS
Status: Firewall Forward / Wiring

DanH · Class G Joined: 22 Sep 2008 Posts: 7

Don't need to buy a special drill bit. Grab an old, dull bit you might be ready to throw away. Hold it parallel to the surface of a hone stone and drag down the stone so as to put a flat where there was a cutting edge on each flute. The flats should be about parallel to a plane in the long axis of the bit. The idea is to convert the edge from a cutting wedge to a scraper.

Be sure to mark this bit with some tape before you throw it back in your drill box <g>
_________________
Dan Horton
RV8 QB
Barrett IO-390

Mike Balzer · Posted: Tue Nov 18, 2008 4:29 pm Post subject:

I have found that an Uni-bit works great when you have a small pilot hole.

I have installed a couple of windows in aircraft by this method

good Luck,

Mike Balzer
_________________
It is better to be on the ground wishing you were in the air, then being in the air and wishing you were on the ground. N78MB

Bob Barrett

My friend who I will leave nameless carefully drilled and clecoed his canopy to the slider frame after carefully cutting the canopy. He enlarged the holes to the next size and left it in the unheated EAA Chapter hanger here in Minnesota. One day another member of the Chapter was out looking at things in the hanger and ZING! A cleco sailed over his head from the canopy hit the wall. When my friend returned from Texas in the Spring he found a nice big long crack in the canopy. My friend had the privilage of ordering a new canopy and match drilling it to the holes in the canopy frame. Needless to sat he enlarged the holes in the second canopy considerally! I also made the holes in my canopy extra large.

Mike Balzer · Posted: Wed Nov 19, 2008 1:42 am Post subject:

I couldnt agree with you more Bob,
I use to enlarge the holes to 1/4 for a 3/16- 10/32 screw. You defiantly need some clearance.

Mike Balzer
_________________
It is better to be on the ground wishing you were in the air, then being in the air and wishing you were on the ground. N78MB

gsimatos · Class E Joined: 19 Oct 2006 Posts: 182

Again, Thanks very much for the info you guys. Gary

gsimatos · Class E Joined: 19 Oct 2006 Posts: 182

While I am thinking about it what sort of drill speed do you think is best. I have a portable drill which turns very slowly and I get pretty nice holes. This is with the regular metal drill in a practice piece of plexi. I do however get chips when the drill emerges on the opposite side. Maybe more RPMs with the air drill would be better. Anyway, ain't going near the canopy til I have a couple of hundred nice holes. I will try modifying a drill but failing that I will give Avery a call. THX Gary

Bob Barrett · Posted: Wed Nov 19, 2008 11:03 pm Post subject:

I purchased my bits from Avery or Cleveland. I felt that it was cheap compared to the price of a new canopy. I keep them seperate and don't allow anyone besides an airplane builder to use them. I just recently had to use one my self for something. I don't remember where or why but it is nice to have some bits you know will work on Plexi with out harming it.