RV-7 rudder trailing edge hole spcing

[skatetrainer]

Does anyone know the dimensional hole spacing for the trailing edge rivets? I would like to let the computer drill the holes in an angle iron rather than hand drill through my skins as a guide. Vans will not give out this simple information. It is proprietary even though I have one of their kits. I'm going to suggest the include the spacing on the next mod of the plans. This is the CNC age.

Dave

 

[andrew phillips]

use apropriate degree of accuracy for job

Dave. This might be the CNC age but you are building an aluminum airplane with technology that is decades old. Squeezing small pieces of metal through holes to fasten metal sheets is not high tech. Using the holes in the skin will result in an excellent job. Of more concern will be making sure the trailing edge is straight and the skins are tight! If you were making vanes on a turbine I would totally support your approach.

Free advice!

Andrew

 

[roee]

Either way...

Dave, I agree with Andrew that CNC is overkill for that particular job. But if you have ready access to the equipment, and you really have your heart set on it...

Just measure the center-to-center distance from the bottom prepunched hole in the skin to the top prepunched hole, and divide by the number of holes minus one. There's your hole spacing, as accurately as it can be measured. Just make sure you set up your CNC job so the hole positions are absolute, so any rounding errors don't accumulate from hole to hole.

In any case, first drill 3/32". Then enlarge to #40 in assembly with the skins (preferably using a reamer). That'll get you nice clean concentric holes, whether you use a CNC, or match drill like the rest of us.

Good luck! And like Andrew said, save your effort for where it really matters.

-Roee

 

[skatetrainer]

Relented: Used angle and drilled

Thanks for the help. Drilled angle at 3/32 then #40. Used laser level to assure that the angle was indeed straight. Prosealed the trailing edge.