Big Apple Hobbies

Installing Brushless Outrunner on ParkZone Typhoon - Part I
The plane is a Parkzone Typhoon, but the basic steps and procedures are applicable to any similar plane. A few words about means and madness .... I mean methods...: you will note that I made no measurements throughout this conversion. There’s nothing wrong with this if you take your time and eyeball things thoroughly before you cut. A lot of times you need careful measurements, but not all the time. There are 2 related articles that will go with this project: how to use Baking Soda, and How to use CA Glues. These have not been written at this time (Oct 27, but will be shortly). When they are done, they will be listed here. The plastic threaded inserts are available from Big Apple Hobbies for $10 for a multi-pack. The pack includes 16 inserts each in #2, 4, 6, 8 and eight each in 10 and 1/4” size. They can also be used for metric screws. You can pay by Paypal or by Credit Card over the phone. Details coming soon. The plywood used is 1/64 and 1/8” lite ply. You can substitute other sizes, but these sizes work really well for this size plane and they are both super-easy to work with. Sanding cannot be over-emphasized. You need a good sanding block, and you need to get the pieces to fit properly. Take a few extra minutes to round the edges and make things look pretty and you’ll end up proud to show off what you’ve done. This particular plane originally had the motor right up close to the firewall, and pretty much nothing at all in front of that. My mod moved the CG forward by placing the new motor about 1” forward of the old location. CG location is important - measure it before you start to do anything, and then make sure you shift things around to get the CG in the same location once you’re done.
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1 - The firewall has little ridges that point the gearbox down to achieve proper downthrust. (Typhoons seem to have no sidethrust built into either the firewall or the gearbox.) Downthrust / sidethrust can be adjusted by sanding the base of the plywood box or by shimming the spider mount with washers. 2 - I cut off the plastic nubbins with a razor saw to provide a flat surface. Attaching the motor direclty to the firewall would quickly result in a broken firewall. 3 - Cutting off the side nubbins.
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4 - This is as close as I could come with the saw. The rest will have to be sanded off. I find Dremels a little hard to control so I prefer hand sanding. 5 - Nice and smooth. 6 - Cut off a piece of 1/64 plywood a little larger than the firewall.
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7 - glue the plywood to the firewall with medium CA. Don’t spare the CA and use foam-safe if your plane needs it. 8 - trim it as close as you dare with a strong scissors and then sand it flush to the edge. 9 - here I’m holding the motor in place to see how far forward it will end up from the firewall.
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10 - Cutting a strip of lite-ply for the mounting box. Notice that even though I haven’t actually measured anything, I am using a tri-square to make sure the cut is square and the edges will be parallel with each other. 11 - Hmmm..... probably won’t be enough here. 12 - So I cut a second piece the same size as the first.
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13 - I cut off a piece to serve as the engine mount plate. 14 - I marked the long edges of the plywood pieces in red, so that when I have a bunch of small pieces cut out, I’ll know which edge I want facing the back. Here I’ve made a box by just gluing one piece after another around the aluminum mounting spider. Don’t rush here and take the time to bevel the edges properly so you get nice strong joints. 15 - Box is finished.

Go to Part II

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