VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics


Go Back   VAF Forums > Main > RV General Discussion/News
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 09-01-2008, 11:47 PM
thelynns thelynns is offline
 
Join Date: Jan 2008
Location: Vancouver, WA
Posts: 84
Default Countersink diameter to accept a #40 dimple.

Hey gang,
I'm ready to counter sink the many small #40 holes in the wing spar to accept the skin #40 dimples. A bunch of them.

Did you guys sink the counter sink just enough to make a 3/32 rivet head flush? Or did you go deeper until a test dimple sits totally inside the counter sink? (This might be too deep). Or somewhere inbetween.

I would like to know what diameter your counter sink is that accepts the #40 dimple.

Thanks gang. Ed
Reply With Quote
  #2  
Old 09-02-2008, 12:29 AM
Flying Scotsman Flying Scotsman is offline
 
Join Date: Nov 2005
Posts: 1,256
Default

I have a bunch of test pieces, made from all the thicknesses of skin, with properly sized holes (#40 and #30) and then dimpled for 426-3 and -4 rivets. I use this, as appropriate, to set the size of the countersink correctly...the dimpled skin must fit inside the countersink.

BTW, if you haven't done so, countersink and rivet in the nutplates (I think it even says so in the instructions), to keep the countersink pilot from wandering...you'll end up with a hole on the "inside" of the countersink that is a bit larger than a normal drilled and dimpled hole, IIRC.

Bottom line...make some test pieces and check for fit.
__________________
Steve "Flying Scotsman"
Santa Clarita, CA
PP-ASEL, ASES, Instrument Airplane

RV-7A N660WS flying!
#8,000
Reply With Quote
  #3  
Old 09-02-2008, 01:33 AM
rv8_builder rv8_builder is offline
 
Join Date: Feb 2007
Location: Pretoria South Africa
Posts: 82
Default Female dimple die

We use the female dimple die to determine the depth.

Insert a short 3/32 rivet in your female dimple die and measure the distance the head sits below flush with a vernier.

Machine countersink until the rivet head is the same distance below flush as measured in the female dimple die.

We used this method on all the wing spar countersinks with good results.
__________________
Andre & Nico Burger
South Africa
RV-8 Flying

Our Build Log
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 06:18 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.