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Tank dimple dies

TShort

Well Known Member
For those of you who used the special tank dimple dies, where did you use them?
Are they intended for the substructures (ribs, stiffeners, etc) on the tanks with normal dimples in the skin, or are you supposed to dimple everything (skin included) with the special dies?

Thanks
Thomas
-8 wings
 
My understanding is that they are to be used anywhere that pro-seal goes in between a joint. I have not sealed my tanks yet. With the service bulletin I guess my laziness has finally paid off :D

Anybody else have input?
 
Becareful with tank dimple dies. A friend of mine building a 7 used them on his tank skins and was not pleased with the results. The tank dimple die makes a slightly deeper dimple to supposedly allow for sealant around the rivet. This deeper dimple also causes the hole for the rivet to enlarge more than a regular die does. When he was done riveting the tank he had a dozen or more rivets that actually could be rotated in the hole. The rivets were bucked correctly having proper shop height and dimensions but were still loose. It is possible the holes could have been slightly elongated from drilling because the skin is radiused in that area and perfect alignment of the holes is not always attainable, but I think the regular dies give you a margin of error to work with where the tank dies don't.The shank of a rivet will only expand so far. I used the regular dies on my tank and did not have a problem. I would experiment first on scrap pieces and measure the difference between regular and tank dies and also using the proseal, if you are really set on using them. I believe Vans would have specifed using the tank dies if it was really necessary.
 
For a second there I thought your tank dimples had passed away. ;)

I used tank dimple dies on my tanks. I think they were from Cleaveland. I don't think it really makes that much difference. Next time I wouldn't bother with them. I had no issues whatsoever with holes being too large.

Dave
 
I have used them on most of the sub-structure with no issues so far.

Tank Die on the right... you can see the slight difference in size.
050617_004.JPG
 
re:-10 tanks

I used the tank dimple dies on everything for the tanks on my RV10. I didn't "final drill" any of the skins or ribs. Just dimpled. I have both tanks completed & attached to the wings now. I filled both of them completely full of gasoline, let them sit for 2-3 days & had no leaks on either tank. :)

Marshall Alexander
RV10 wings/ailerons
 
I used the tank dies on the ribs of my tanks and was very pleased with the results. The first few holes seemed a little large so I re checked my squeezer settings. With the piston fully extended, I fit a piece of sheet the same thickness as the rib between the flat areas of the dies and adjusted the max closure to be just a snug fit. That way I didn't over dimple the hole. Just my two cents worth of advice, Mike
 
RV10Man said:
I used the tank dimple dies on everything for the tanks on my RV10. I didn't "final drill" any of the skins or ribs. Just dimpled. I have both tanks completed & attached to the wings now. I filled both of them completely full of gasoline, let them sit for 2-3 days & had no leaks on either tank. :)

Marshall Alexander
RV10 wings/ailerons
Final drilling is a very important step. When the holes are punched in the parts for the matched holes it forms a burr and also the inside of the hole is very rough. Final drilling will remove that roughness which when expanded by dimpling will cause microscopic cracks if not pre drilled. I believe you should always final drill and deburr the edges of the hole. I've read some guys drilling with a #41 to still keep the diameter smaller for dimpling but don't know what issues this might cause either. I've seen items written before on this forum about dimpling without drilling and I don't think it is a good practice.
 
Brockster said:
Final drilling is a very important step. <SNIP> I've seen items written before on this forum about dimpling without drilling and I don't think it is a good practice.
Ditto...I also think it is good practise to final dril, I have also heard people talking about it, but I don't know enough or have facts at hand..Anyone have a link to real experience on this?
 
Zombie Thread Alert!

I hate to revive a thread so long ago put to rest, but I have searched extensively for the answer to the same question the OP here asked, and have not found a real answer. I have found pages and pages of people arguing over whether the tank dies will cause leaky joints, weak joints, sneaky joints, and joints that will either make you rich and famous or steal your girlfriend and impoverish your dear old Grandma, laughing at you the whole time and posting naughty sectioned pictures of themselves for your spouse to see the next time she/he has a look at your web browser history.

Can anyone answer the question:

Are the Tank Dimple Dies meant to be used on the outer skins, substructure (like ribs), or both? If they are to be used on the outer skins, what does one use on the substructure? If they are to be used on the substructure, what does one use on the skin?

Don't even get me started on the "substructure" dies!

Sorry once again, but if anyone can answer or point me to any link that shows a consensus on the subject, I'd appreciate it.
 
I hate to revive a thread so long ago put to rest, but I have searched extensively for the answer to the same question the OP here asked, and have not found a real answer. I have found pages and pages of people arguing over whether the tank dies will cause leaky joints, weak joints, sneaky joints, and joints that will either make you rich and famous or steal your girlfriend and impoverish your dear old Grandma, laughing at you the whole time and posting naughty sectioned pictures of themselves for your spouse to see the next time she/he has a look at your web browser history.

Can anyone answer the question:

Are the Tank Dimple Dies meant to be used on the outer skins, substructure (like ribs), or both? If they are to be used on the outer skins, what does one use on the substructure? If they are to be used on the substructure, what does one use on the skin?

Don't even get me started on the "substructure" dies!

Sorry once again, but if anyone can answer or point me to any link that shows a consensus on the subject, I'd appreciate it.

Why not call Mike at Cleveland Tool (guy who makes them) and ask him?

My understanding is that the tank dies were made a bit deeper to allow for making a deeper dimple on the skins so that a small amount of sealant can be under a rivet head without making the rivet protrude above the skin surface. I would think that this would require also using them on the sub structure (ribs etc).

Snipped from Cleveland web site-

Tank dies make deeper dimples to allow for the layer of tank sealer between the rivet and skin.
Rivet will set flush with the skins surface.
Spring back angle on die faces.
Minimizes skin deformation.
Skins remain very flat!
Precision made on our CNC machine.
Stainless Steel- Heat treated.
Polished dimpling surfaces.
Don't make 14,000 mistakes on your plane!
See also DIE-KIT.
We guarantee these dies work better than any others or we will give you a refund!


TECH INFO:

These dies make a dimple 0.007" deeper than our standard dimple dies to allow for the proseal under the rivet head. Historically builders have had to use a 'rivet shaver' bit which can easily get out of control. With these dies used on the TANK SKIN and on the TANK RIBS the rivets will set perfectly flush after riveting.

Also if you purchase the dies they can be used on the substructure of the entire airframe. If you have ever noticed that the skin and the substructure dimples don't nest perfectly we have created a special die for those discerning builders that is 0.011" deeper for the ribs and stiffeners, allowing the dimples to nest together rather than smashing together during the riveting process. If you purchase the tank dimple dies we recommend that since you have them, use them on the substructure of the rest of the airplane too!


They also have a video on their web site that apparently (I haven't viewed it) discusses their use.

Note, this post is not an endorsement of their use.
My recommendation to builders when they ask, is to use the standard dies and remove excess sealant from the dimples before inserting the rivets.
 
Note, this post is not an endorsement of their use.
My recommendation to builders when they ask, is to use the standard dies and remove excess sealant from the dimples before inserting the rivets.


Recommend anyone that is thinking about using Tank Dies do a little research on percentage more blisters there are on Painted Tanks that have been built with Tank Dies.

Expect to find that tanks built with "Tank Dies" have a higher percentage of blisters under the paint than the tanks built with "standard dies." Once you have your research complete, proceed with the method of your choice.
 
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