There comes a time in a build project where you just have to commit. To me, that day was today.

I had previously cut up the aluminium N-filter to match the curvature of the shell (fairly well), and today was the day when I decided to really fix it in to place.

I had decided, however, to add a smoke machine and some lightning inside this part, so I needed to make it accessible. The only way of doing this, would be to either have it bolted on somehow, or cut open the shell. I opted for the second option.

I marked the outline of the n-filter with a marker (on to painters tape, as I had already painted the bulk of the shell, I then went on with drawing a line offset 5-6 mm inside the outline, and used this as an outline for the hole I was going to cut up.
I didn’t want to just start cutting with my dremel as I have had “accidents” with the cutting wheel before, so I opted for something more safe. Drilling holes. A lot of them

Once I had drilled holes all around, and in some places, used my power drill as a mill, this is what I was left with. A big gaping ugly hole. It did however proved ample access from the inside:

In comes the rotary tool with a sanding extension to clean the jagged edges up nicely. I did touch up some of the cutouts on my N-filter as well, as I had moved it slightly from the originally planed position.

In order to fasten the metal N-filter to the fibre glass shell, I used a two-component epoxy putty. The drawback of this, is that it is fairly fast curing, so I didn’t have time to pause for pictures while doing this.

I first rolled a long snake of the putty once I’ve worked the hardener into the material, and pushed right inside the outline of where the N-filter would go, and then pushed the N-filter (hard) in to place, squishing the putty down. I then removed excess material, and worked up a new bunch of epoxy putty, making snakes again, and this time pushed in the material in the joint between the fibre glass shell and the aluminium filter. Using the wooden end of a fine paintbrush, rubber gloves and pure isopropanol, I smoothed the edges out and cleaned off excess material.

The isopropanol I have in my workspace is fairly strong, 99.5%, so in addition to the gently rubbing to smooth the putty out, I removed some paint at the same time.

After I was happy with the putty (it took me 3 rounds of adding and smoothing), I let it sit for 10 minutes (I did say it was fast curing) and then gently painted over the joint with normal black paint.

I figured that if the filter was attached to the cyclotron, which was texturized, and welded in place, the paint which was added would not have been texturized. It turned out just great.

Here’s a picture from the inside:

I have since reinforced the joint slightly from the inside, and removed excess putty with an exacto knife. Next session, I will grind the opening inside to perfectly match the N-filter, then reinforce some more, and start working on the drop-in insert that I am building for the light and smoke machine.

As a final teaser, here are some of the things that dropped in the past week:

The crank knob is the real thing. Just the wrong colour. Will need to trade or paint it. We’ll see.