Swappable Mini Telemaster (Part 2) Glow Power

If you read Part 1 of my mini swap-emaster article you can probably tell that I am pretty new to the hobby. Besides the swap-emaster, I have done a few other scratch builds and a speedbuild Spitfire. And of course I own a Bixler. So I am starting to feel like I know a thing or two about RC model airplanes.

Well imagine my surprise when recently I was browsing the HK website and I came across a totally new type of motor called "Glow". "WHAT IS THIS EVIL WIZARDRY?!" I screamed. Apparently Glow has been around for a few years. Unlike normal motors, Glow motors do not require electrical battery power to spin the prop. It sounded too good to be true. But I went ahead and ordered the cheapest one possible, an AP .15 hornet, to give it a try. Two weeks later the motor arrived along with the various other bits required and after an hour or so of fiddling it started right up. Amazing. 

Now I just needed a model to put my new motor in. I looked around the shop and saw my mini swap-emaster hanging innocently on the wall. Could I make a Glow pod in the same manner as the normal FT electric power pod? The answer is yes and here it is. Prepare to have your mind blown:

There is a mount available for the AP .15, but I could not find one for sale online. I did buy a small plastic universal glow mount from HK, but found it too bulky. So I made my own mount out of wood to exactly fit the power pod firewall. The mount has hardwood rails with plywood gussets and it is glued and screwed to the firewall. Also the firewall itself is thicker than the normal firewall in the power pod plans.

The motor is bolted to the mount with large washers and plenty of loctite.

I painted the mount flat black so that it would not throw of the lines of the plane too much. I considered extending the cowl cheeks, but then I would not be able to still swap in the electric pod because the prop would hit the cheeks.

Here is the new pod mounted on the plane.

The fuel tank that I selected does not fit completely in the pod. Also, I found that I had to actually raise the tank a bit further to get the height of the vent more or less level with the carburetor. Here is the fuel tank poking up through the fuselage bulkhead. 

One benefit of having the tank come through the bulkhead is that it prevents the tank from move around. So just a velcro strap is needed to keep it secure. I considered making a deeper version of the FT power pod so that the fuel tank would fit better. But I thought that might throw off the whole design ascetic. The downside is that I can't put the glow pod directly into another model without also cutting a hole. It is easy enough to make a new power pod, so I may try a deeper one in the future.

The AP .15 is somewhat over-sized for the swap-emaster. I was worried from the start about the plane being too nose heavy. But, surprisingly, it balances reasonably well. I placed the fuel tank right at the CG. And I put all of the electronics at the rear of the pod. I was expecting to have to move the servos to the tail to get a little more tail weight. But this was not needed. Even though it balances, it is probably somewhat over-powered. Going from a 450 electric to a .15 sized glow is a decent jump in power.

And now a few words about fuel-proofing. It is my understanding that foam models are not usually used as glow models in part because fuel can damage some types of foam. I tested on some painted dollar tree foam and the fuel does not seem to do any damage or peel the paper. It did fade the paint a little. I think the bigger issue is that fuel will soak into the foam over time. I put packing tape over the areas of the model that seemed most likely to get splashed with fuel or exhaust. And I covered the exposed edges of the foam board with a film of hot glue. Also, I covered every part of the power pod with extreme packing tape. I also considered simply covering the whole model with covering film. My motor mount is glued with wood glue. I probably should have used epoxy. Since the mount is also screwed to the firewall, I don't think it is a safety issue, but I will have to keep an eye on the glue joints. But what do you think?

So how does the mini swap-emaster fly on Glow power? For that you will have to wait for read Part 3 because I haven't actually tried it yet. Although I have done some taxi tests and the plane looks and sounds awesome.

Has anyone else tried a Glow motor on a swappable?  I really like the idea of being able to swap between glow and electric on the same model.