A while back I had gotten away from using the OEM control horns because I always had a really hard time drilling straight through for the top and bottom pieces to line up with the screws without making it look like swiss cheese. Ive since started to use the Dubro HD control horns which only use a single bolt; which is a bit easier, but the use of a drill press would probably help to get a perfect result. I have no plan on getting a press, so was wondering if you guys had any useful tips for others to get proper alignment when drilling holes for the screws. Any tips would be appreciated.

Thanks

I usually tape half of the control horn to the surface with a long thinstrip. Next, I use a strong sewing needle to push through the control horn and through thesurface and slide the 2nd half of the control horn over the needle. Then you should be able to drillstraight without too much trouble.

Good luck...

I would use the needle method but instead of a drill bit try some 1/16 copper tubing with teeth filed on the cutting edge the tubing will not wander like a drill bit does.

Find someone with a drill press then use it to drill some straight holes through square hardwood blocks. On a flat control surface these can be used as a guide to keep your drill bit exactly perpendicular and make more accurate holes with a hand drill.

Are you drilling through tapered ailerons? Keep in mind that a drill press will not help you on tapered stock unless you shim the tapered end so that the drill travels through the material perpendicular to the center line of the aileron. I mark the holes position with a Sharpie Ultra Fine Point then start the hole with a pin so that the drill doesn't wander. Another method is to use a very small straight bit screw driver and just spin it back and forth between you fingers. I used this technique for years. The small driver in the Stanely jeweler's screwdrivers worked great.

Right!

And that's the problem... that you need to drill perpendicular to the surface chord line, which is at an angle to the surface itself.

A drill press and a jig makes this much easier but it is a lot to deal with for a small hole.

I end up using a small finger drill, will looking at the control surface from the side, edge-on.

I normally drill the first holewith a finger drill, unless I have harden the surface with CA, then I use a cordless drill. Once I have the first hole drilled I put the control horn on with the bottom piece also. I then push a T-pin through the other hole and out the bottom plate. Now I have a line to drill the 2nd hole.

The above is exactly what I do.

If your surface is not tapered and you don't have a drill press, then this is another option:

http://www3.towerhobbies.com/cgi-bin...?&I=LXL780&P=7

I use smoke and mirrors. Works every time. Ye ole mark one eyeball sight gauge.

Practice, Practice, Practice, Practice, Grasshopper.

Cheers

I also use a pin vise and drill the holes with that...I use a drill one size larger than the 2-56 screw, then (mock-up ) install the horn...then remove screws and harden the holes w/ thin CA.
Another tip is to grind a point on the ends of the screws...helps 'em to get started in the nylon nut plate.

I was actually thinking of getting a pin vise. Excellent tip on grinding the screw points. Thanks for the tips guys! Much appreciated.

I use a sharpie to mark the holes on the horn side then push a pin through to line up the back plate, when aligned I mark the holes, then I drill aprox half way through the surface to meet the 2 hlfs.
also sharpen the ends of the screws they find the holes easy enough, I use a dremmel cut off wheel to remove the exess on the ends that protrude past the plate.