Originally Posted by solentlife
Foam vs balsa .... the problem here is supply. In Latvia we have only 2 shops and they are 3hrs drive away and prices are unreal. The size balsa they have is limited also. Foam is available 5 mins walk from my house !
I'm a traditional old fart builder balsa etc. but have graduated to replace in various areas with foam ... good example is where I crashed my Ultimate Bipe (World Models wood job) and rebuilt front with foam blocks and wood spars. Same weight, but quieter and motor mount is far better now.
I like the gearbox idea ... but prefer efficiency of brushless motors ... and the reduced weight of them.
All good stuff ...
Yes I have the Outerzone as a favourite and have downloaded the plans etc.
The best plan of course is the Tony Nieuhaus one as the Plans service also offers vac-formed turrets / canopy etc. to fit ... but it's not cheap ! I remember back in the 80's when it was featured in UK Magazine .. with 4 x 20 IC glow motors. I had the plan but lent to another ... we were going to build it for a Club Display model ... unfortunately he passed away and plan got lost with his things when cleared out.
I'm thinking that the formers etc. shown on plans can still be made up with foam .. I found it surprising how stiff a structure can be once formed even with thin foam. That SE5 wing was an eye-opener.
To keep weight down - it's possible to laminate foam either side off thin balsa ... gives good stiffness but light weight ...
I'm really open for all ideas ... and I do apologise if I don't use odd ideas - no offence meant ... at end of day - I will have to work as materials available dictate and also my ability.
The end result is to do honour to my Mum who worked on Lancs during WW2 ...
I can understand the balsa dilemma. I glue scraps together to create sheet for cutting formers. I only throw away balsa scraps under 1/2" in size, and have all my scrap balsa from when I started building in a small box. Even with the recycling program, it's still expensive, and has something to do with why I build mostly smaller scale planes. At 70", it starts to get expensive.
The geared 370 setup is a brushless setup. They are actually a bit more efficient than an outrunner, when ideally setup. Using props like the GWS HD is less efficient than the SF prop on the setup I showed, but they really sound like a fuel engine. I have one that people have thought was a really smooth running glow motor. The exact motor of the one I showed was a Himax 2015-4100, which is generally considered 370 class, such as the Park 370 inrunner. Four of them should provide ample power for a Lancaster of around 50" to 70", or even larger. The gearboxes are getting a bit harder to come by however, with GWS not producing much. The GWS cloned gearboxes such as Eflite are too expensive at $10 US or more, for what I care to pay.