Dimpling Laser Pointer

I saw this idea while searching through various toy... err... tool websites. They had created a small laser pointer for locating the dimple die when doing large skins. As a new builder, I have found this somewhat frustrating and thought it a pretty clever idea. However, the price tag seemed rather high, so I took a look at making one up myself. I found all of the pieces I needed at Amazon and in the HF Aviation section. I actually ended up with enough parts to make two for less than the cost of the unit I saw on the web. I dimpled the Top Side Skins today and it worked very well. I think, over the life of the project it will save well over the time needed to fabricate it.

The laser module is a Farhop "Focusable 650nm 5mW 3-5V Laser Dot Module" and the battery/switch box is an Uxcell "3x1.5V AA Batteries Holder On Off Switch". The flexible arm and articulating joint came from the HF "inspection mirror". I assume everyone has the JB Weld needed to glue the "arm" to the battery box and the laser module to the articulating joint end. Also, I used some Velcro to hold the assembly to the DRDT unit. Be sure to get a "focusable" module as the set up distance changes and the focus is actually pretty sensitive. I'm not sure if the "cross" modules are focusable, but I figured I'd go with the sure bet. Pictures are posted below, and if anyone has questions, let me know.

https://jimpyne.smugmug.com/RV14-Tools/i-pGtHVsn/A

https://jimpyne.smugmug.com/RV14-Tools/i-hDpfQdD/A

Smart idea, but I have always just put the male die half in the top of the dimpling tool.
You can easily see the reflection of the pilot in the skin making it very easy to align with the hole.

rvbuilder2002 said:

Smart idea, but I have always just put the male die half in the top of the dimpling tool.
You can easily see the reflection of the pilot in the skin making it very easy to align with the hole.

Click to expand...

I started off doing it that way but after a couple of close calls when a skin shifted before the pilot was set almost resulted in a skin punctured in the wrong place, I began keeping the male die on the bottom for more positive positioning.

Using a DRDT?

Been doing it male die on the top for 25 years with a C frame and never had that problem because the die only touches the skin when the pilot is being lowered into the hole.
Male die on the bottom works ok for flat skins, but in my opinion it makes it much more difficult when doing wing leading edge skins or bent trailing edge skins for control surfaces not present on an RV-9,10, or 14.

I too was enamored of the laser hole finder but ultimately implemented a low tech, no batteries required method as shown in picture below. It consists of a short piece of insulated copper wire with a jewelry bead epoxied to the end. The whole affair is attached with some 100mph duct tape and can be easily adjusted using simple finger pressure.

I adjust the bead so it floats close to the edge of where the dimple die pin is located. When the piston is lowered, the bead gets pushed to the side and snaps back to position when the piston is raised. The wire is flexible enough so that I can easily move the wing skin around, but as I get close to aligning the next hole the bead accurately indicates where the pin is. This simple device easily doubles my dimpling speed.

Unintended consequences

Curious why are you dimpling with blue plastic still on?

If you leave the plastic on you don't end up with scratches from the die pin dragging on the backside as you position the skin for the next hole.

smash said:

If you leave the plastic on you don't end up with scratches from the die pin dragging on the backside as you position the skin for the next hole.

Click to expand...

Forgot about that one.... one more benefit to male die on top.

Dimpling with plastic on, on skins that have been final drilled is considered less than ideal. There will always be some drill swarf caught under the plastic that then gets mashed into the skin surface.
Even if the holes were punched final size, if you do any amount of deburring there will still be swarf caught under the plastic.

I use the DRDT also but with the male die on top as much as possible.

After I dimple a hole I lift the lever just enough to clear the hole, then slide under the pilot and lift the sheet. It slips right in and I just keep a little pressure up as I push the lever down.

Never missed a hole on the entire 14 build. However, I do have two dimpled random holes in the skin not near a hole. But that's a story I'm too embarrassed to tell.

smash said:

If you leave the plastic on you don't end up with scratches from the die pin dragging on the backside as you position the skin for the next hole.

Click to expand...

In lieu of relocating the male pin, I just lowered the lower frame below the level of the carpet so the skin would have to be pushed down to engage the pin. If it was not aligned, then no hammer. It solved the scratch issue for me and never punched an extra hole. Like Scott said, the reflection of the upper die is an excellent indicator of location.


Free advice: Keeping the mind engaged is more important than a rapid (mindless) production rhythm and will eliminate such mistakes. Usually an extra hole (or something else like it ) will occur to train each one of us early in the process.

smash said:

If you leave the plastic on you don't end up with scratches from the die pin dragging on the backside as you position the skin for the next hole.

Click to expand...

But do you get a nice crisp 'corner' on the dimple crater? I'll bet there are more under-dimpled skins in the RV world than properly dimpled ones.

Made-up words...

Scott,

I was going to accuse you of making up "swarf" but it is in the dictionary. You sir are a true airplane nerd.

rvbuilder2002 said:

Forgot about that one.... one more benefit to male die on top.

Dimpling with plastic on, on skins that have been final drilled is considered less than ideal. There will always be some drill swarf caught under the plastic that then gets mashed into the skin surface.
Even if the holes were punched final size, if you do any amount of deburring there will still be swarf caught under the plastic.

Click to expand...