Counter Sink or Dimple

For general discussion of the Just Aircraft family of aircraft.
Includes: Highlander, Escapade, Summit and SuperSTOL.

Moderator: scubarider2

Counter Sink or Dimple

Postby BucF16 » Sun Mar 06, 2016 4:17 pm

Quick Question; The manual calls to countersink the rivet holes on the trailing edge metal (both wing and Flap/aileron). I have always heard that one should dimple in AL with thickness less than .041. I tried to counter sink a sample, and to get the correct amount of "sink", the hole became irregular. Any thoughts?

Thanks,
Bruce
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
User avatar
BucF16
Veteran Member
 
Posts: 111
Joined: Sun Mar 23, 2014 11:47 am
Location: Alexandria, Ohio

Re: Counter Sink or Dimple

Postby SheepdogRD » Sun Mar 06, 2016 4:59 pm

I drilled the holes, disassembled, dimpled the trailing edge material and countersunk the capstrip. That produced a flush surface without removing metal.

I also used a rivet washer on the capstrip side to prevent pull-through.
Richard Holtz
Highlander N7340Z -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
User avatar
SheepdogRD
Veteran Member
 
Posts: 683
Joined: Tue Nov 30, 2010 5:41 pm
Location: West of Atlanta, GA

Re: Counter Sink or Dimple

Postby BucF16 » Mon Mar 07, 2016 8:54 am

SheepDog, Thank You for the quick response! Your method is as I intended to approach this issue. This makes me feel better about my intuition going forward. It's been a few years since I've been engaged in a project.

Cheers,
Bruce

Hey BlueMax, Get to Work :mrgreen:
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
User avatar
BucF16
Veteran Member
 
Posts: 111
Joined: Sun Mar 23, 2014 11:47 am
Location: Alexandria, Ohio

Re: Counter Sink or Dimple

Postby danerazz » Tue Mar 08, 2016 8:11 am

You countersink material that is as thick or thicker than the rivet head height, you dimple material that is thinner than the rivet head.

The main thing is if you were to countersink, it should not make the hole larger than what you drilled.
Dane

Paralysis by analysis
#242
danerazz
Veteran Member
 
Posts: 876
Joined: Tue Aug 18, 2009 9:33 pm
Location: Bangor


Return to Just Aircraft