HI blucher,
The PT109 was built from a Dumas Boats plywood kit which is reasonably heavy, very strong and quite rigid. it has a quite shallow prop shaft angle which allows the motor to sit very low in the boat, and it sits just above the keel. There is not much else in terms of weight other than the batteries, and I have experimented to the extent of fitting four smaller batteries connected in parallel, all sitting on the bottom skin of the boat. They can't get any lower and still be inside the boat! The boat still wants to roll.....
The Perkasa I built was from a Precedent kit with the plywood hull and it was relatively straightforward and very satisfying to build. it isn't plank on frame thank goodness but just uses plywood and a small amount of balsa. I covered mine with fibreglass cloth. My build blog showing the Perkasa and some pictures of the PT109 frames is on this website, and if you go to this link it will take you there directly:

http://model-boats.com/builds/view/13599?goto=13635


The Perkasa is a BIG heavy boat and if you want some speed out of it then you need a lot of power. I have used a single Turnigy 4084 - 620KV brushless motor which gives a very high speed without the complication of two motors/controllers/props etc. At speed this motor delivers about 1.2kW. if you go to this link on this website:

http://model-boats.com/user/lauriem

you will see the power setup for this boat. At my club there are four Perkasa's including mine and this motor and battery combination gives the best performance by far - much better than boats with two motors.

Yes I guess that it might have been a bit difficult. Never mind, it is good to chat with you through this website if that is all we have available at present (barring Star Trek Transporters!!!).
😯 👋

nice looking boat,hopefully mine looks this good when finished