NebulaDDS

One of the biggest problems I have is making my drill holes perpendicular to the firewall. I can measure quite easily where the holes are supposed to go, but the drill bit always seems to deviate a little on the way out. Simply eyeballing it doesn't work very well. And, since my plane is almost completely built, it would be very difficult for me to get the firewall into a position where I can look straight down at it. All I have at home is a hand drill.

....So....

Is there any kind of small device that I can use to ensure that my drill bit will go through the firewall perpendicularly?

If you have your own tried-and-true method, I'd really appreciate it.

GalenB

My Feedback: (18)

Harry Higley makes some tap and drill guides that are pretty slick. I use mine all the time with great success.

http://www.hobbylinc.com/htm/hig/higtnd011.htm

MHawker

My Feedback: (16)

Nebula,

There is a hand drill attachment that is exactly what you need. I've never tried it on planes, but I don't see why it wouldn't work. It's a housing that fits on the end of your drill and makes it operate like a drill press. It's not the one that your drill clamps into (although that would work too if you could get your plane underneath it), it a small enclosure of sorts that adds a base to your drill which would sit on the surface you want to drill.

Check Home Depot. I'm sure they have it.

Sorry, I just re-read that and confused myself. Sorry it's not more clear. Let's face it, some people have a way with words and other people........ uhhhhh

Mike

Charlie P.

Use a carpenter's square or modeler's right angle held beside the drill-bit to help you visualize alignment. It is amazing how accurate the human eye can be in determining alignment.

Set the plane flat on a surface and lay the drill on a pile of magazines/books/wood set high enough to bring the bit to the proper height. A variation is to place the drill in a miter-box on the stack - poor man's drill press. Note that this only improves one axis - you still need to worry about the other. (see above)

Like GalenB mentioned - use a jig. You can make these ahead of time by drilling holes in blocks of hard rock maple or aluminum (or having a friend with a drill press do it for you).

Use a finger drill and measure frequently with the edge of a paperback book or some known right-angle (you really should have a set of modeler's or drafter's angles if you don't already).

Kaos Rulz

..... Make a set of jigs out of solid, square, aluminum. 3/4 to 1 inch square will work fine. You can drill one side at 1/16, then rotate the jig 90 deg. and drill a 3/32. Your second piece could then be drilled 1/8 and 5/32. Those 4 sizes should take care of most of you needs; if not cut another jig and drill whatever ya need. The trick here is to get someone with a drill press to accurately drill out the jig holes.

Stew99

All the above suggestions are good. I personally like the Higley drill guides. If you have to "eye ball' it, a good technique is to use an extra long drill bit. This helps make any misalignment more obvious.

MinnFlyer

My Feedback: (4)

First, spin really fast...

Sorry, couldn't resist. But here's an easy jig you can make yourself out of two pieces of wood...

John La Belle

My Feedback: (52)

A real simple way I have used on full size homebuilt spars etc. is to use a highly reflective film( alum. foil etc ), with the film on the surface hold the drill point in position and move drill arround until the reflection is a straight line with the drill John

HalH

My Feedback: (12)

I would buy a 1" thick piece of acrylic clear plastic. Use a drill press to make a hole or holes to guide the drill. With the plastic it is easy to align the block in the proper position.

MHawker

My Feedback: (16)

I can't believe I can't find that adapter. I found a couple of similar things, but I can't find the exact thing.

Here are a couple of links and a pic. The first link is the closest to what I'm talking about.

http://www.rockler.com/ecom7/favorites.cfm?sku=2406

http://www.amazon.com/exec/obidos/tg...&s=hi&n=552496

Good luck.

Mike

rajul

My Feedback: (58)

If you don't have a standard or Dremel drill press, go for the Higley tap and drill guides. I use them regularly and are one of the indispensable tools I have.

mikenlapaz

Try taking a piece of 1" x 1" x 1/8" 90 degree Alum angle stock, cut it to about 1" length. Make very sure your cuts are true 90's,
file to true 90, debur, sand end cuts. Either hold or tape this RIGHT ANGLES 90 TOOL in position use the the end and outside edges as you visual references.

Most bits are long enough to allow them to rest lightly against the perpendicular end cut.

Got me thinking.... what is so critical about the holes being @90 degrees? If for blind nuts, I end up making them a tad larger for alignment anyway. drill small , enlarge with adjustment to angle.



For practice ( DDS ) set-up a mirror and use it for sighting!

Cdallas2

Invest in a drill press. The smaller ones are fairly inexpensive and once you have one you'll never know how got away without one for so long.