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Anybody wanna see a Fusion 75?

12K views 183 replies 17 participants last post by  joebob 
#1 ·
Been thinking a lot about what to replace my demolished 30cc Primo with and had pretty much settled on building another GBR70, but after reading through my previous build thread, I started having second thoughts. So I started rooting around the shed and found an old Fusion ARF that a buddy gave me a while ago. It was really beat up, but intact enough to get some good measurements from. So I scaled it up a little and started drawing out the construction. To save on wood, I plan on doing a foam wing with foiled ailerons. Fuse construction will be similar to the GBR using a lite ply skin, but instead of a single tube, I plan on using the carbon fiber/balsa sandwich beam design used in the old Fusion kit.

No clue how it will turn out, but should be a fun build. Still working on the fuse panels and deciding where to add the structure so it will be a little bit before I actually start gluing anything together.
 
#6 ·
Something about Knife Edge and GBR's.. Definitely the best KE plane I've ever flown!
 
#10 ·
Wild Fred said:
lite ply not the best for structural. just sayin. what does real acft ply weigh in 1/16 or 1/32 by comparison?
Don't know. But I have lite ply so that's what I'm using. The GBR70 seemed to be plenty strong. For my flying style, it should be fine. I don't do much high energy stuff. But we shall see!
 
#13 · (Edited by Moderator)
Got all the parts in to make my foam cutter. In the past, I have used a Radio Shack transformer and dimmer switch. Worked, but barely. And now that RS is out of business, I had to come up with something else. This is what I got, and it works great.

24V 10A power supply:
https://www.amazon.com/gp/product/B07QM ... UTF8&psc=1

Speed control:
https://www.amazon.com/gp/product/B0874 ... UTF8&psc=1

Power Supply AC cord:
https://www.amazon.com/gp/product/B07C9 ... UTF8&psc=1

26ga Nichrome wire, 100ft
https://www.amazon.com/gp/product/B07CH ... UTF8&psc=1

Also got some ultra flexible hookup wire to go from the supply to the bow.
https://www.amazon.com/gp/product/B01M1 ... UTF8&psc=1

Total cost was $43. Picked up a piece of 1/4" music wire from Ace and used some scrap 1x2 I had laying around and made a bow. With 36" of nichrome, I had to set the speed control to about 7V for a nice easy cut. So there's plenty of headroom for longer bows. Mounted the speed control on top of the supply with some velcro and it's ready to go!

20210311_133751_resized.jpg
 

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#14 ·
cool! i just use my battery charger, it has foam cut settings under special modes. hooks turned me on to that, i was using the old skool dimmer switch and xformer. but the charger works great, can set amps, volts, time.

you will find foam is awesome if you work with it's particulars. i'd use c/f stringers and balsa sheet the foam fuse, using appropriate things for hard points, motor mounts, etc. leave the lite ply out. the i beam of 2 c/f stringers and balsa sheeting lighter, almost indestructable, shatterproof. but what does wf know about engineering? :lol:
 
#17 ·
If I had enough balsa, I'd do a skinned foam fuse, but I don't have enough and don't want to order more right now. So, I'm trying out some different building techniques to see how they will work. Might do one later and compare. If nothing else, it will give me a good idea of what kind of weights I can achieve with this technique.

If anyone has about 15 sheets of 1/16" balsa, or whatever thickness WF suggests and wants to donate it to the cause, I'm open to it! lol
 
#18 ·
Well,i dont know much but,weight is bad,if you going to put that much love in it,a few sheets balsa be well worth it. WF is spot on,and you want it to be the best it can,go the extra mile. He does know foam,but its your plane,we want to watch you build it either way,going be neat. Going check out your cutting setup now.
 
#19 ·
Wild Fred said:
cool! i just use my battery charger, it has foam cut settings under special modes. hooks turned me on to that, i was using the old skool dimmer switch and xformer. but the charger works great, can set amps, volts, time.

you will find foam is awesome if you work with it's particulars. i'd use c/f stringers and balsa sheet the foam fuse, using appropriate things for hard points, motor mounts, etc. leave the lite ply out. the i beam of 2 c/f stringers and balsa sheeting lighter, almost indestructable, shatterproof. but what does wf know about engineering? :lol:
What charger is that? Would love to have one!
 
#20 ·
So WF, just to appease you, I ordered a bunch more balsa so I can do a foam fuse. Still looking at alternatives to tubes which are a little less expensive. My original idea was to use some of that Dave Brown CF tape, which I have on hand, and make 2 1/2"sq laminated beams from 1/4" balsa and CF. One running along the fuse bottom and the other toward the top. Another idea was to get that CF strip like Swany supplied with his kits for the spar lamination, but it's kind of hard to find, and I don't know what it's called. Also, would it be better to have the CF lamination running vertical or horizontal?

Second, would the 1" blue foam would be a better choice for a plane this size, or will the standard white foam be OK, assuming it's fully sheeted? I got enough wood to do it in either 1/16" or 3/32". Which would be better?

Still not giving up on the lite ply design, but now I can do both and see which is better.
 
#21 ·
standard white. i beam the spar like my newer designs, along motor mount to rear, like i do with my newer stuff. the foam to balsa bond is the most important, the foam and balsa aint strong- the bond is. thin coat poly, wipe with credit card, preferably vacuum bag or at least a shitload of weight,

indestructable. and light.

the fusion series is a good design, especially in larger sizes. i talked with mike a lot back around 2004-5 about the design and slab evolution. is a little small to work in 40 size, but the bigger fusions fly awesome. i'm looking forwards to your build, as your attention to detail and construction techniques are awesome- and you a good guy... i met you at least once when bfc was flying, before he ****** out and went biking and skirt chasing. :lol:

all you need to get a tight tail holt on the world is a little w.f. engineering... old yeller quote, btw.
 
#23 ·
joebob said:
So WF, just to appease you, I ordered a bunch more balsa so I can do a foam fuse. Still looking at alternatives to tubes which are a little less expensive. My original idea was to use some of that Dave Brown CF tape, which I have on hand, and make 2 1/2"sq laminated beams from 1/4" balsa and CF. One running along the fuse bottom and the other toward the top. Another idea was to get that CF strip like Swany supplied with his kits for the spar lamination, but it's kind of hard to find, and I don't know what it's called. Also, would it be better to have the CF lamination running vertical or horizontal?

Second, would the 1" blue foam would be a better choice for a plane this size, or will the standard white foam be OK, assuming it's fully sheeted? I got enough wood to do it in either 1/16" or 3/32". Which would be better?

Still not giving up on the lite ply design, but now I can do both and see which is better.
This is what we used -
UNIDIRECTIONAL CARBON FIBER, 3.7 oz./sq. yd., 12" wide
Unidirectional
0.005" Thick
Webbed Binding
Unidirectional Carbon Fiber, 3.7 oz., 12" wide, 1-9 ft.
Item #: CF341
Price per foot, Minimum quantity 1 ft. $5.62

https://www.cstsales.com/a-carbon-fiber ... abric.html
 
#24 ·
Thanks for the info. I found some strips at AloftHobbies that are .8mm x 1" so I ordered a few to play with. Also got some 12mm tubes in case they didn't work out.

Also, got an email from Sig saying they were out of balsa for a month or so, so I cancelled that order. Guess it's back to National.
 
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