DRDT-2 Set Correctly?

At the point on the vertical stabilizer where it says to dimple the skin. Don't want to screw the dimples up and curious if I have the DRDT-2 set correctly. The dies completely touch each other and there is about another inch of handle travel over the cam. Is that correct? Keep seeing video about proper dimpling and they talk about reflections not being distorted except for the actual hole. I'm not seeing that perfect reflection. Their is reflection distortion beyond the actual hole. Am I under dimpling, over dimpling or what ? A rivet seems to sit nicely in the dimple. Is the whole reflection distortion critical of should I just dimple away and quit worrying about it. I'm a new builder and the learning curve is mind numbing. LOL Thanks

If you're distorting the reflection around the hole, you're probably under dimpling. Its pretty hard to over dimple. Spring-back dimple dies are just like the name implies. When you bottom the die out, the squeezer should spring back.

This video shows it perfectly. Not a fan of the lack of narration while the compressor is running. But, watch till the end and he will explain.

https://www.youtube.com/watch?v=Qo9QCMaNSoA

You should see a light ?witness mark? (faint concentric circle) around the dimple. If it?s not there, adjust the fully closed dimples closer together. The drdt arm should be pressed down hard enough that the back end would come up, if it?s not bolted down.

Easy "rule of thumb": Set the travel for the DRDT-2 such that when you fully compress the dies (pull handle down) with your test coupon, there should be a slight deflection in the arms of the drdt-2. I.E. you are putting enough force on the sheet metal and the DRDT-2 such that there is a little flex on the steel C-frame. Witness marks are also a great visual indication that you are successfully dimpling.

If possible link to a photo / video of your test dimples or see if anyone local can swing by to take a look. As others have said, it's pretty hard to over-dimple.

1 turn down from die to die contact

Here is a LINK to a post I made back in 2009 about DRDT-2 setup with a photo showing the difference between different "preload" settings. The one turn preload I believe is the manufacturers recommendation as well.

You should see a light ?witness mark? (faint concentric circle) around the dimple.

Click to expand...

This ^^

If you have a pneumatic squeezer put a set of dies in it and dimple some scrap, it will show you what you should get when your DRDT-2 is properly adjusted.

My DRDT-2 loosened up a bit over time, I used some blue locktite on the nut.