Introduction: Making Perforated Brass for a Star Trek Communicator
I needed some perforated brass for a project and it's either extremely rare or hard to find, or both. I've seen ready made pieces, for what I'm building, go for $200-$300 on eBay, but that seemed a bit steep and at that price I decided to make my own. But some tests that I did using a center punch to try to get the right pattern and spacing, did not turn out great. So, I had the idea to use some perforated steel, (which I was able to find with the right hole pattern and spacing) as a drilling guide/template. The spec for the brass that I needed comes from the following site:
https://www.herocomm.com/PartsAndPlans/Antenna.htm
Tools and materials needed:
- K&S Brass sheet - #16405 (6" x 12" x 0.025" thick) This is very close to the thickness of the original material used.
- OnlineMetals.com - perforated steel - #13526 (12" x 12" with 0.036" Thick x 0.0625" Hole x 0.125" Stagger (Mild Steel Perforated Sheet A36 Round Hole)** The key here is the offset hole spacing matched the spec.
- 5/64" drill bit (this is the size of the holes needed in the brass)
- 5/32" drill bit (to drill the corner anchor holes)
- Power drill
- A piece of scrap lumber (I had a piece of 2" x 12") to anchor the pieces
- A piece of scrap aluminum 1/16" thick and at least 3" x 3.75"
- 4 - 1/8" x 1-1/2" lag screws
- tin snips
- de-burring tool
- magic marker
Step 1: Getting It Ready
The first thing that I did (using the tin snips) was cut 1 piece of the perforated steel, 3 piece of the brass and 1 piece of the 1/16" aluminum into identically sized pieces - 3" x 3.75".
Next, I drilled 4 holes, 1 in each corner of all of the metal pieces, and then using the lag screws, I anchored the stack of metal sheets to the piece of scrap lumber, in the following order:
- 1 piece Aluminum on the bottom (protects the last sheet of brass from being deformed)
- 3 pieces of brass
- 1 piece of perforated steel on top as the drilling guide/template.
Step 2: Drilling the Brass
I didn't need the entire area drilled, only a section about 1.75" x 3.25", and I used a paper template to trace the area needed, onto the perforated steel.
Then I started drilling, and drilling and some more drilling...
Some drilling tips:
- Keep the RPMs relatively low 600 - 700 RPM (this yielded the best results)
- Use moderate pressure on the drill, also for best results
Doing both will reduce the amount of burrs left around the exit of the drilled hole.
If you have a drill press, of course the results will be even better.
Take your time and take some breaks, between sessions, as this will take some time, there are ~435 holes to drill.
Step 3: Final Resulting Pieces
The end results where even better than I expected. There were some variations in the sheets of brass depending on which sheet of the 3 you look at. The top sheet of brass was excellent, with almost no burrs around the holes. The other 2 brass sheets did have some burrs, but still not terrible and a de-burring tool can take care of those.
I had switched drills, near the end of the drilling and it had somewhat higher RPMs, that's how I could tell that the holes from the lower RPM drill were better.
The final cut and trimmed piece of brass, from one of the sheets is shown in the last 2 pictures. The first shows the piece lying on top of a brass rod frame, before it was bent into shape and soldered to the frame.
The last picture shows my first attempt at the end goal for the use of the this brass, which was to make an authentic replica of a Star Trek TOS Communicator antenna grill. I'll go into some of the details of shaping the antenna in another Instructable. I'm not quite finished with that build yet, as I'm still waiting for some material to make the custom hinge wheels that the antenna frame will be attached.