Dimple skin and countersink connecting thick aluminum angles

[dhogue]

Hello Sonex builders,

I am working on the cockpit side panels of my Onex kit.

I am going to use Flush CCC-4x rivets on the thick vertical angles and the skin.

I will Dimple the Skins.

I will countersink the thick aluminum angles to which the above dimpled skins will be attached.

I am using scrap skin thickness material and scrap thick angle material to practice countersinking the angles so the dimpled skins fit with no gap between the skin and the angle.

I am using the Sonex simple dimple die to Dimple the skins and a 100 degree micro-stop/countersink on the thick angles.

I am having to countersink the angle holes very deep to get the dimpled skin to fully seat to the angle. I am concerned at the depth of the countersink.

I post to ask if you know of a dimple/countersink method that works for this scenario?
(I did do a search but do not see a post that addresses this scenario)

Thanks,
Don

[rk2436]

You want to countersink using a 120 degree cs for pop rivets,regular an rivets are 100 degree.

[Bryan Cotton]

I agree with Bob. I totally missed that you were using the wrong countersink the first time I read your post.

[jowens]

Hi Don,
I had a difficult time finding a source for a 120 degree countersink that goes into a microstop. I have had excellent luck with the yard store for tools.

http://www.yardstore.com/countersinks/1 ... 0-deg.html

I'm not sure how the Onex engine mount is attached to the fuselage, if it is the same as the Sonex you will need a 1/2" 100 degree

The Yard Store is also a good source for reamers.

[dhogue]

Thanks guys,

The 120 degree C/S drill bit solved this for me.

Don