Sig Akromaster weight

[gene poremba]

 This is my first post, i have been quiet & reading & learning for the past year. I'm building a Sig Akromaster & my un covered weight so far with OS 15 LA (r/c carb) & everything ready to fly is at 14 oz. I'm planning on silkspan & dope on the fuse & silk on the wings. I built the wing without cutting the leading & trailing edges, so its just a bit larger than stock. I'm not sure what the added weight of the finish will be, but if i come in under 20 oz ready to fly, would you say thats a good target weigh for a good stunt model? Thanks....Gene

[Dave_Trible]

Hello Gene and glad you are here!  You are in good shape with the weight of your Akromaster.  Don't go overboard with the finish on this plane.  I'll take it this will be a trainer of sorts for you and it will show scars soon enough.  Try to get it pretty straight and just go fly the dickens out of it.  Good luck and have fun!

Dave

[gene poremba]

 Glad to hear that! I was getting concerned since it was at the 14 oz mark with out the finish Anyway, i'll try and keep everything as light as possible from here on....Gene

[John Craig]

Your LA 15 is a bit heavier & much more powerful than the engine the kit  was designed for.  It will want to fly FAST. I have 2 kits but I have built neither.  I will use an old Cox .09 or a Fox 15X when I do.   People say an OS .10 is enough.  Check your CG, you are most likely a bit nose heavy.  Using the full wingspan available was a very good move.  I do not think your weight is to far off.  Keep the amount of dope & particularly colored dope to a minimum. 6 oz is a lot of dope & silkspan for a model that size.  Remember to thin your dope & particularly colors before applying thin light coats. Light is might when you are talking flight. Post pictures & tell us how it flies. Best Wishes1 !

[Andrew Hathaway]

The Akromaster will carry a lot of weight within reason, just don't go crazy on the finish.  Most of mine were covered in Sig Koverall (not light), the last one had a 1/2" fuselage with a stretch - Fancher Twister style, with an FP 15.  It flew decent on 60' .015s.  From time to time our first Akromaster still gets flown, it's mostly oil soaked fiberglass and CA now, and the OS Max 15 is about worn out, but it still flies reasonably well on 57' .012s.  The LA 15 will have plenty of power to carry the weight, run longer lines to slow it down.

[gene poremba]

 Thanks everyone for the input on my Akromaster build. I'll post pictures of it soon. Right now its in the bones waiting to be covered. Hopefully this weekend. I'm looking foreward to getting it in the air. I have been flying my Bi Slob, with an old 35 red head, in the mean time when the weather co operates. It is an ARF just to get me back in the air again and from what i'm hearing much slower! ....Gene

[gene poremba]

 9oz at this point

[gene poremba]

 I put down 3 coats of nitrate, lightly sanded in between, applied Esaki heavy silk ( i fly from rough fields) put on 3 coats of nitrate to seal the silk and it added .7 of an oz. So my airframe is at 9.7 oz. I'm trying to keep the weight down as much as possible. I'll post pics when i get some color on.....Gene

[gene poremba]

 As promised i said i would post some pics once i got some color on my Akromaster. Well, i finally got a free weekend to do some spraying & this is my take on the Akromaster scheme. Its at 13oz as it sits right now. Still needs engine & fuel tank & prop......Gene

[Perry Rose]

I built one last winter that weighs 19 ounces with an old Fox .19,no muffler, an 8 x 5 Zinger prop, a 1-3/4 plastic spinner, 2 degrees engine offset wedges, on 50 foot, eye to eye, Spectra lines. The balance point is at the trailing edge of the leading edge piece. Or a half inch behind the wing leading edge. It flys very well with this combination.

[gene poremba]

 
 Thank you for that information. I'm just a weekend sport flyer at this point & looking for it to do basic stunts, loops, wingovers, inverted etc. I'm creeping up on a larger stunt model, right now i'm really trying to learn how to get a nice finish & keep it light! I think i needed to sand off more of my primer to help keep the weight down. Each time i put one together i learn what to do or not to do on the next one. I never worried about the weight when i was a kid and some how everything flew! I'll get there eventually...Gene