Concerned about under dimpling, Please let me know your thoughts

[ctremie]

Alright! Cleaveland Dies ordered and Overnight! will know and update tomorrow, about to break this handle trying to add more pressure! lol

Thanks guys!

[robertahegy]

I have never used a DRDT-2 but I would guess the speed at which the metal is upset is as important as the pressure. I know my pneumatic squeezer was very quick and a hammer blow on the C frame is quick. I would think the speed that the DRDT-2 is operated could influence dimple quality.

Roberta

[PilotjohnS]

Another user of the DRDT2 and Cleveland dies.
I really don't like the wack-a-mole C-frames; seems too primitive and too easy to miss and get the hole in the wrong spot. JMHO.
But the DRDT2 needs to be set so the frame warps a little and leaves the donut rings.

[bjdecker]

Originally Posted by robertahegy

I have never used a DRDT-2... I would think the speed that the DRDT-2 is operated could influence dimple quality.

Doesn't appear to make a difference -- slow (#1), fast (#2), C-frame (#3)

The C-Frame dimple (#3) is a tad distorted because the dies aren't aligned quite right.

Or course, you would need to look at the cross section of the material with a SEM or similar device to determine the granular structure...

[Everwild]

I've been using the DRDT-2 with Cleveland dies and have it adjusted so the top arm of the c-frame flexes upward roughly an 1/8th of an inch when fully engaged.

It leaves clear witness marks on both sides of the skin and overall am satisfied with the crispness of the dimples.

[BobTurner]

When I look at the photos in post #1 I see a series of "dots", for lack of a better description, around the dimple. What you should see is a faint smooth ring. Not sure if it's the dies or under-dimpled. The DRDT doest take a good push - certainly, the DRDT must be bolted to the table or the back end will lift up. If it's not and it's not, you're not pushing hard enough.
BTW: my opinion: C frame is better in the hands of a pro. DRDT is better in the hands of an amateur. I used the DRDT!

[ctremie]

Originally Posted by BobTurner

When I look at the photos in post #1 I see a series of "dots", for lack of a better description, around the dimple. What you should see is a faint smooth ring. Not sure if it's the dies or under-dimpled. The DRDT doest take a good push - certainly, the DRDT must be bolted to the table or the back end will lift up. If it's not and it's not, you're not pushing hard enough.
BTW: my opinion: C frame is better in the hands of a pro. DRDT is better in the hands of an amateur. I used the DRDT!

Yes mounted and sturdy!

[Girraf]

I use a DRDT-2. I set the dies up so that I see about 1/8" of flex in the body of the unit when I full depress the handle when there is no material in the way. I'm using springback dimple dies. When I'm finished, I usually see a ring around the dimple about 1/2" in diameter and when I look at the reflection in the metal, there is no distortion except for where the metal was deformed to create the dimple. I've been satisfied with the final riveted results. I've never used a C-frame so I can't compare.

[Captain Avgas]

This is another groundhog day thread. The same thread pops up every year....mostly the same answers....mostly defence of product choice...it's all in the archives.

As previously submitted this excellent and informative video from Cleaveland Tools comparing the DRDT and C-Frame sums it all up. In essence both tools will do the job but the C-Frame will do it a bit better.

https://www.youtube.com/watch?v=_mpbsQF1eu0

The reason the C-Frame produces crisper, more defined shoulders at the dimple is purely because it exerts a dynamic pressure as opposed to the DRDT which exerts a static pressure. It's that simple.

If the shoulder of the dimple is not well defined....ie. a curve rather than a distinct change in angle ....the rivet will set slightly high. This is easy to test for....just run your fingernail across the factory head of the set rivet. If you get ANY catching on the rivet whatsoever your dimples are not well formed.

This is not a structural issue...it's largely a cosmetic issue. So in the end it just comes down to how fussy you are. If you're very fussy go C-Frame....not so fussy and the DRDT is fine.

[tyconnell]

Originally Posted by wirejock

I prefer a C-frame.

What Larry said.