VAF Forums

VAF Forums (https://vansairforce.net/community/index.php)
-   RV-9/9A (https://vansairforce.net/community/forumdisplay.php?f=5)
-   -   Dimpling fuel tank skins (https://vansairforce.net/community/showthread.php?t=103588)

Future RV 9 Flyer 08-26-2013 08:21 PM

Dimpling fuel tank skins
 
I started to dimple my fuel tank skins and them I heard about Clevelands fuel tank dimpling dies.Are they needed or are the regular 3/32 dies ok?

N9331v 08-26-2013 08:24 PM

Tank dies
 
I used the tank dies. They make up the difference for the depth of the tank sealant so the rivet does not sit proud.

sbalmos 08-27-2013 07:23 AM

Agreed. Get the fuel tank dimple dies. Even just that little dab of sealant that you will put in every rivet hole makes up the difference.

YellowJacket RV9 08-27-2013 09:48 AM

I used them on skin and ribs of my first tank, then I read a bit more about them and heard they were not supposed to be used on the skins, only the underlying pieces, so that's what I did on the 2nd tank. To be honest though, I don't see a difference. Rivets are flush on both skins, so it appears they work as promised, and no leaks.

David Paule 08-27-2013 10:38 AM

Wide Confusion
 
See http://www.vansairforce.com/communit...d.php?t=101941 for which one to use where.

Dave

Future RV 9 Flyer 08-27-2013 08:23 PM

fuel tank dies
 
thanks for the advice,ordered the dies from Cleavland today. dimple the skins and then on to sealing the tanks.

JENSWAY 08-31-2013 08:49 AM

TANK SKIN DIES
 
I don't quite understand- I'm about to dimple my tank skins with the tank skin die. Is the "substructure" die the 3/32 or is there a particular die for the substructure dimple?

Bevan 08-31-2013 10:30 AM

I believe the "tank dies" are intended to be used for the under structure, (to make a slightly deeper dimple). Then use the 3/32 die for the skin. The theory is this allows room for some sealant to get trapped in between the skin and the understructure.

Clear as proseal? :)

One potential problem is that if the skin dimples are not placed directly over substructure dimples prior to riveting, the cleckos will still go through and look right but the rivet may "tip" slightly when set. This will result in one edge of the manfactured head's edge protruding slightly leaving a sharp edge you can feel with you finger. I'm not sure if this was caused by using the tank dies or having proseal involved or both.

Bevan

longranger 08-31-2013 05:09 PM

Quote:

Originally Posted by Bevan (Post 803061)
I believe the "tank dies" are intended to be used for the under structure, (to make a slightly deeper dimple). Then use the 3/32 die for the skin. The theory is this allows room for some sealant to get trapped in between the skin and the understructure.

Clear as proseal? :)

One potential problem is that if the skin dimples are not placed directly over substructure dimples prior to riveting, the cleckos will still go through and look right but the rivet may "tip" slightly when set. This will result in one edge of the manfactured head's edge protruding slightly leaving a sharp edge you can feel with you finger. I'm not sure if this was caused by using the tank dies or having proseal involved or both.

Bevan

The "tank dies" are to be used for dimpling the SKIN to allow room for a thin layer of sealant between the rivet and skin. The "substructure dies" are to be used on the ribs to allow the slightly deeper dimple in the skin to nest properly in the rib dimple.

If you are doing structure other than that which requires sealant you can use the tank dies for dimples in structure for skins dimpled with "standard" dies.

In one instance, the wing walk, I used standard dies in the outer skin, the fuel tank dies in the wing walk doubler, and substructure dies in the ribs.

Bevan 08-31-2013 07:06 PM

I agree with the previous post and stand corrected. The substructure AND skin would be dimpled with tank dies making a bit of room for sealant under the rivet head. I can't say this works any better than reg dies as the extreme clamping pressure of the rivet should squish out all of the sealant.

Bevan

JENSWAY 09-01-2013 02:16 AM

[quote=longranger;803184]The "tank dies" are to be used for dimpling the SKIN to allow room for a thin layer of sealant between the rivet and skin.

Thanks for the clarity.


All times are GMT -6. The time now is 01:28 AM.