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Slab for os32/40fp recommendation

2K views 26 replies 8 participants last post by  kamlooper 
#1 ·
Looking to build a profile for a small engine, like a Pen Knife size or similar, any plans around?
Thanks
 
#2 ·
Hey Kam, any slab can be scaled up/down to a 40" wingspan, which is proportionately close to the 2.5-3lb auw ideal for a 40fp, with a header/pipe, of course. :drink:

Primo 25 is closest without much adjustment :tu:
<<<<------- avatar photo
 
#4 ·
just build a light one. see, the fp is 12 oz. a 4 0z. tank plenty of fuel. mount standard servos in wing like the burrito, and you got a sub 3 lb. mojo. there's a thread on one I did a dozen years ago. I routinely did 2.5 lb. fp powered lamyaks, and now use 35-42 on 3s batteries on same weight plane which works even better.
 
#7 ·
I scaled a Chinn Yak down to 87% -41" winspan for a 40FP. 41" and 2 1/2 to 2 3/4 pounds is where you want to end up at. 3lbs is not Bro power. My plane pictured came in an ounce under 2 and 3/4 pounds.
It is a fun bird, but I feel like electric is better.
Also in my opinion the 41" stix is the absolute best plane in this class.
https://www.theprofilebrotherhood.com/forum/viewtopic.php?f=110&t=37317
 

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#8 ·
kamlooper said:
Is that the Mojo 25? I found the plans for them. Im thinking of building something other then the primo since I have a primo 40 to construct.

Edit:, chit, I cant cut all those pieces lol
no, it's a stock mojo. use a built up mount and select light wood. make the gear out of 1/8 wire, as it'll hold 3 lb. fine. very few pieces to cut; just ribs. i routinely make the canopy frame out of 3 pieces 1/8 balsa glued together. and i make fuse 1/2" thick. still under 3 lb. you gotta know you save about 7 oz. just in motor/tank/gear. another oz. on the mount.

viewtopic.php?f=21&t=3776&p=54988&hilit=laminated+mount#p54988

is how i make my engine mounts. electric similar, it's shown on my later build threads.
 
#10 ·
video of it flying here. it has the west on it there. i'm flying the original .91 lamyak, the white/orange one. donnie is flying W.W.'s slide 58, richard's recording. recording, and tigman is flying the primo. maybe not? at the end, he's got his hands in his pockets... i think he landed sooner tho. and as a side note, i built all 4 of those planes! i about forgot how solid the .91 powered lamyak is in hover, it's a big puppy.

I'm glad that richard's videos are still there. lot of fun stuff. the spongebob hoovering is priceless!
 
#20 ·
Two pieces of 1/8" ply laminated for the motor mount will be just fine. In my opinion 1/16" for the ribs will be okay, unless it is to low density wood. If you were worried about the 1/16" you could add a small 1" wide doubler with the grain running vertical at the spar.
 
#24 ·
hey,what happen to the slicks, i was getting all worked up,a great flying small plane,tell us more,lots 40fps sitting in boxes,lots of cheap 2st engines have no home. can these small planes truly fly well,with no batterys or if we got to,el power. go VOTE you cant charge your planes in a blackout,and save the balsa trees for planes.
 
#25 ·
If I have dxf files for it (slick) ready to go, I could make some parts. Its a learning curve for me, it took some time to pull these ribs off the pdf plans, convert and place them for cutting. In the end i fucked up and it cut the little support bracket off the bottom of the ribs. I taped them up then tack ca'd them so they can still be used.
A huge shout out to Makerspace for cutting these for me...great bunch of people at my location.
 
#26 ·
Zombie [2point0 said:
":lqdrxvqm]
kamlooper said:
Thanks! Thats a sic avatar, looking back at cam while hovering!
I love the dangling cigarette. Cracks me up!
Pro Bro Gus took that photo at Beaver Bro, in Powers, OR back in the day.. :drink:

Pro Bro Frisbee sells a kit of the wagas yak designed for the 40fp, it's called the Yak 40. He built me one, then kitted it. :rockon:

 
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