I'm building a light weight SSE - shooting for a shade over 4 lbs AUW
will I get away with a Hit-tec HS81 MG servo in a somethin' extra wing? (two servos - one in each wing)

The default servos on the plans is a standard 42 oz inch job, but the HS 81 pulls 36 oz inches - at just half the weight, will it be robust enough?

I.F.

Those should be just fine. My standard JR servos are 40 in-oz and they will work in just about all 40-60 sized sport planes. You have a light weight WWI model that will certainly perform less stressfully. I think they should work out fine.

I don't think he is talking about a WWI model. He is talking about the Sig Somethin' Extra. Yet the standards should be fine anyway. I use standard ball bearing futaba's in mine and it does just fine.

You're RIGHT! I read SSE as SE5. Oops. (It was early in the morning ) Dyslexia b*tch is a.

I tried the using 85MG's in the back end of a Funtana 40 and found that although they had enough torque, they didn't have enough throw. You may want to check this out before committing to this mod.

Hope this helps.

Yea the servos should be OK, If installed right the need for power is not huge and I have seed all sorts of servos used in the SSE. You are right to make it light, we have found that the weight is the single biggest factor in how it flies. We leave off lots of parts and give up crash survival for better flight performance.

You should got down the statement above so you can read it after you land hard and split the fus in half

Don't think it's a good idea with 81 MG. SSE is a funfly/3D and micro servo on it - no-no. SSE is not a park flier. It needs HS225MG at least. Don't fool yourself with MG gears, they are not too strong anyway on micro servos.
As for me I am going by now with Saito 82 and hitec 5975 digitals (bought them on sale) on my SSE.
If you need a plane like SSE but fragile and very light go with Magic Extra.