I had the basic shape for the dumbbell’s weights finished. Next up I had to figure out how to wrap foam around it, and make the whole thing actually look like a dumbbell… somehow.
The next step was to put strips of foam around both of the ‘weights’, to give them the appearence of being completely solid (which they definitely aren’t). There was a problem, though: I needed to know the length of these foam strips. What to do?
I had a variety of metal and plastic rulers and calipers, and even a sturdy tape measure… but none of these things could help me. They were all too rigid, for one. For another, the foam I was using had a thickness of 1cm. Even if I’d used a flexible cloth tape measure to measure the circumference, the result would only be accurate for the innermost circumference. Not the outside. Plus… I didn’t have one. So… that was a problem.
After thinking it through, I came up with this:
It’s a ruler made out of 1cm thick foam! That way I can make an accurate measurement that takes the thickness of the foam into account. I simply cut off a 100+ centimeter strip of foam and copied the measurement indicators from my ruler to the foam. I used the factory edge for this to make sure I had as straight a line as possible.
With this, I was able to accurately measure the length of foam strips I’d need, and cut off two identical pieces – one for each of the ‘weights’:
I also beveled the edges. I was afraid that the pieces wouldn’t match up neatly enough… in hindsight, I don’t think this was as necessary as I thought it would be at the time:
To connect the beveled edges together and turn both strips into circles that would fit over the current frame of the ‘weights’, I applied contact cement to the edges, let it dry a bit, then made the circles:
They’re not perfect… because everything was cut by hand, and I eyeballed the slope of the beveled edge as well, things didn’t line up well:
Plus, the glued area still managed to “poke out” as a result:
Still, I’d already improvised a lot, and I figured that I could just continue to improvise along the way. After all, a test fit of the foam circles around the frame of the ‘weights’ made them both look pretty impressive at this point:
Before I continued, I wanted to fix some of those issues I’d introduced. This started by using a rotary multi-tool and manual sanding to sand down the glued-together edges. Here’s a comparison picture, the glued edge on the left side is sanded and on the right side it is unsanded:
Yeah, that’s a pretty big difference. Of course, I sanded down both of the weights eventually, not just the one. 😅
Next up, it was time to glue the outer circle onto the inner frame to make a permanent connection. I actually had a really cool idea for this: hot glue!
“But”, you might say, “that’s ugly!”. Ah, ye of little faith… this is entirely intentional. The great thing about hot glue is that once it’s painted over, it looks just like a thick weld line – which wouldn’t be out of place at all on some significant weights.
After this, it was finally time to work on the rod.
As you can read in part 2, I’d bought a thin and light-weight plastic-wrapped metal broom stick that cost me €0.70 at the time. The first thing I had to do was cut off an appropriately-sized piece.
This wasn’t hard. I simply placed the two weights side-by-side on a flat surface, then pushed them further apart until they were some distance apart that I was satisfied with. Then I added 10cm so that the rod could sink 5cm into each of the weights. I then used a miter box to get a clean cut with the right size.
I then had to paint over the blue plastic wrapping… it had a ribbed texture that I wanted to keep, as most weights have some texure on it to enabled an improved grip for the end user. But there was a problem with this plan. I’d already cut off the exact size I needed. So how was I going to paint the entire bar? After all, clamping it in any way would’ve caused obvious missing paint. Even spraying over it later, you’d never get rid of the bump where the paints overlap.
So I came up with this:
It’s a cork from an old wine bottle, screwed into two glued-together pieces of leftover prelaminated chipboard to give the entire thing sufficient weight, with some tape to pad to the right thickness.
This let me take the rod outside to my spray area and spray it with a gray primer, and then a metallic spray paint without missing any spots:
With the rod done, and the weights done, it was time to put the two (three?) of them together. And it literally did feel like it was all coming together at that point. I positioned the rod and glued it into place by forcing hot glue into the small holes I’d made in the weights for that purpose. I’d put some tape on the other end just to make sure no glue would end up falling through. (That’s pretty unlikely, given how quickly the stuff cools once it’s out of the glue gun… but still, better safe than sorry.)
Once this was done, I wanted to get rid of those holes in the middle of the weights. To work around that, I simply created a ‘cap’ out of a piece of leftover foam, then cut some bevels onto it to make it look less dull.
I liked the look of this! I glued the remaining weight onto the rod as well, then capped that end as well. The result really did look like a heavy dumbbell (sans paint job):
There was one final thing I wanted to do before I started priming and painting the rest of it, though. That cap in the middle of the weights looked okay, but I felt like something was missing… I did some google searches and found a couple of images of weights, and came up with the idea of adding these extra strips:
I loved it. It really improved the overall look of the dumbbell, but now it made the inside look bland by comparison… so I decided to cut off a few more strips and apply those strips onto the inside as well:
That looked great. The + shape with beveled center cap really added a lot to the depth and realism of the design. The ‘inside’ parts didn’t have that cap though, and I felt that it didn’t look quite right… so that was something else to work on. But that’s when it all came falling apart… quite literally, in some cases.
In the next post in this series I’ll write about the painting process and all sorts of things that started going wrong with this project. I’m guessing that’ll be the most popular post in this series. People love to see other people mess up. 😛
See you next time!