Perfect #30 holes when dimpling

[Tony Spicer]

Well, having a bit of an obstreperous streak, I think I'll throw out a dissenting opinion. Take a BSC-42 rivet and set it. Don't stick it in a dimple, just set it between your fingers. A bit of spit will prevent a burn. In the few that I did, I noted two things: The diameter on all from end-to-end was uniform and close to .162, and none had proud stems.

If somebody could tell me why the rivet wouldn't swell to fill a .135 tri-cornered hole, I'm all ears.

Tony

[rlweseman]

Excellent! Exactly what the goal is.


Rachel

[jsteere #39]

I think that it is worth using as the resulting hole is much tighter to the rivet than the standard dimpling dies. May not save time since you may still have to ream the hole, but hole/joint quality is better.

I agree with Paul about the value of this process. I do not use the burraway tool, so after dimpling and reassembling the structure, I cleco every-other hole, then, while pressing the skin against the underlying structure, I ream the holes without clecos with a #30 straight flute reamer (Cleaveland Aircraft Tool # RSF30, $9.00 each.) The amount of material removed is very small and leaves a very clean, round hole, that does not require further deburring. It takes the same number of steps, but in a different sequence than the original process, and the final hole is about as perfect as is manually possible. I have completed the tail kit, most of it with this process, with zero proud stems.
John

[at7000ft]

are you using a burraway tool for deburring?

No, I understand from Paul's report that the burraway must ream the hole a little larger in the deburring process to result in the dimpled hole being just the right size.

Rick H

[psalter]

I think that it is worth using as the resulting hole is much tighter to the rivet than the standard dimpling dies. May not save time since you may still have to ream the hole, but hole/joint quality is better.

[rlweseman]

And the point of using the DIENQ, even if you have to ream to a #30, is that the other method of reaming to a #30 and then dimpling was resulting in a hole that was larger than the true #30 hole. Using the DIENQ results in a tighter fit rivet set - even if you do have to ream out to a #30.

[rlweseman]

are you using a burraway tool for deburring?

[at7000ft]

I am using the DIENQ die and need to ream out many holes to #30 to get the rivets in. Is the DIENQ die worth using? Toss-up.

[psalter]

In case you haven't seen the latest update on the FLYWITHSPA.COM update, I used the DIENQ dies and looked at the hole quality with a microscope. The results were surprisingly good, and I believe these will be the dies I will use for the rest of the plane.

http://flywithspa.com/dimpling-for-flus ... te-solved/

[av8shar]

Rick,

Yes that is the order I used, but you might find that #5 may not be necessary (at least for a majority of the holes).

Reamer verses drill bit is a personal choice and I don't believe that you'll need to de-bur again due to the limited amount of material that may need to be removed, just check to make sure they are still good to go.

I'm looking forward to putting this new process into action on my wings.

Andy