Vertical Drill Guide

[NickB]

Just looking for ingenious ideas for a drill guide to ensure my freehand drilling is straight and vertical. I have experimented with different ideas from the internet but most are tailored to woodwork and not for small spaces with small drill bit sizes. I have both electric and air drills and a slab of 2"x 3/4" aluminium bar i have been experimenting with but still lacking that ingenius aha moment of a simple solution.

Does anyone have any good ideas/ techniques they have used with success?

Thanks
Nick BH1172

[N3UW]

You can look at my videos to see what I did but I copied the idea of another builder. I took a piece of 1/4" steel rod and placed it I to my Sioux air drill? I plumbed the rod to vertical with an accurate level, Make sure you have a good level to do this with. I used a good Stabila bullet level. I then attached a bubble level to the top of the drill with a dab of bondo. This has worked very well for me. This is a photo of a page from a document another builder posted a while back that gave me the idea.

[Friesen 5]

While building my Sonex, I used a mirror to ensure that the holes were perpendicular to the surface. I laid the mirror on the surface so that I could see the drill bit and it's reflection. As I drilled, I made sure the drill bit and it's reflection were in a straight line. Instead of a glass mirror, I used a plastic mirror - the kind students use for their school lockers. I cut it to useable shapes and drilled holes in it, all to make the bit and it's reflection more visible.

[alaskabearhawk]

It really depends on what you are drilling. What are you trying to drill? I use different methods for different situations.

[X'N]

Aluminum doesn't make a good drill guide. Use as hard as material you can. Or make jig out of your aluminum and use drill bushing guides http://www.mcmaster.com/#drill-bushings/=tvice6. Cold rolled steel will make a decent drill guide for about 10-15 holes before it starts to wear some.

Then there is also the egg cup type drill guides. They work ok but are most times too big to fit in a rivet line if your still using cleco's to hold stuff. http://omegatec.com/egg-cup-drill-stands.aspx

What are you trying to drill?

[bestbearhawk1231]

I use different methods depending on the situation. I have a egg cup style with threaded bushings but it doesn't get used very often since the rivets are usually placed too close. I will most likely be using an aluminum or steel block and threading it to accept the bushings once I start drilling the spar caps...unless I decide to make the drill press work. I use steel tubing, mirrors, etc. I have never had much luck with the bubble level on the back of the drill trick, my hands are usually in the way. For those it works for, it may be worth your time to do it.

Really need a better idea of what you are trying to drill to give a better answer.

[S Lathrop]

To do my wing spars, I rigged benches on either side of a drill press. I used a drilling template, 1 x 18 x 3/16 steel, that I laid out on a CNC mill to drill every hole in both spars and the cap strips. All the holes were undersized when first drilled. I used #6 screws to fasten the spars to gather and finished by match drilling every hole. I used drill jigs for all the parts that were similar so those parts were interchangeable throughout the wings.

My process avoided the challenge of not drilling long holes square to the surface.


I re-drew the spars in AutoCad. The distance between the rivet holes on the drawings is rounded down so that over the length of the wings, you get a significant error if you use the rivet spacing on the drawings to lay out the spar. But when you calculate the rivet spacing to 3 decimal places you can use the rivet spacing as the layout of everything on the spars. This process allowed me to drill almost every spar part on a drill press.

[NickB]

Thanks guys I am drilling the capstrips using an air drill. The bubble option seems like a good simple idea. I find that every drill bush type guide adds the risk of moving off the centre punched hole as you go to drill as it gets in the way of seeing the drill tip

[X'N]

If you take a look at my thread here it will show you how I did it. CNC's are great for spacing something like this but you could also make one with a rivet fan. http://bearhawkforums.com/forum/bear...ling-spar-caps

I started out drilling them by hand using the jig but ended up going back to the drill press. I'd recommend pre-drilling your cap strips to one size down rivet and then upsize the holes using a hand drill once you have the stack cleco'd in place.

[DRLPatrol]

If you use 6" long drill bits it makes it a lot easier to see if you are straight.

Doug