Viggen

SNAKE

New member
Hi Everyone Just got into building FT foam planes and have access to a laser, Just wondering If the wing is cut by a laser, It can be cut in one piece, Would it be strong enough with out the glue joint or carbon fiber in the wing any help would be appreciated.
Thanks BILL
 

mrjdstewart

Legendary member
yes, you could cut in 1 piece. i would maybe still wrap the middle with tape but other than that, follow the plans.

good luck

me :cool:
 

kilroy07

Legendary member
Hi Bill and Welcome!

and have access to a laser
Man, you are set! What is the working/cutting area? If it's in the 700x500 range I have a bunch of the FT designs already converted to DXF I could share (might save you some time.)

I am curious as well.
I "Almost" had a viggen at FF for David to sign, but I over extended myself and had a couple more pressing projects. Please, keep us posted on how it turns out (I might start cutting this weekend.).
 

SNAKE

New member
600x900 I'm the owner of a graphics and laser company, And I'm always open to sharing, I have all kinds of plans in DFX, Foam electric nitro and gas let me no. Thanks BILL
 

flyfree

Member
Just FYI - built a Viggen (beautiful lines for foam board on the fuselage, and very interesting how they did that). The wings started to show signs of stress on the first flight, and I folded a wing on the fifth flight, despite BBQ skewer reinforcement. The skewer actually tore through the paper. It was a great flyer, and very quick, up to then.
 

kilroy07

Legendary member

SNAKE

New member
Thanks for the info, Do you think carbon fiber would help, I would like to build the kraken next just the for kicks of it, Any thoughts on the
carbon fiber would be appreciated.
Thanks Bill
 

flyfree

Member
I think a carbon fiber spar would help if it was the full wingspan. I used BBQ skewers, which were plenty strong, but each wing was a separate skewer, which allowed them to fold a little right at the fuselage, and eventually fail. I was running a 12 blade 70mm EDF on 4s. It was a bit overpowered. :)
 

kilroy07

Legendary member
I think if we add the etch line in the wing and Add a carbon fiber
I think a carbon fiber spar would help if it was the full wingspan.
I agree. I plan on swinging by the hobby shop tomorrow and checking out what they carry.

I have a 70mm 6 blade (i think you pretty much have to run EDFs on 4 cell batteries to get the thrust you need.)
But, I might build one of the new vipers (F-16) that should be released soon...
 

SNAKE

New member
Hi. Everyone
On a 70mm 6 blade EDF You don't think the Viggen will fly on a 3s, Or is it better with the 4s, Or just go with
a 12 blade.
Have a good day BILL
 

Namactual

Elite member
The EDF's are usually tuned to run on a certain voltage. That is determined by the KV of the motor not the size of the fan. The Viggen would fly with any decent EDF as long as you match the appropriate battery for the power output.

Usually the lower the blade count the more efficient the fan is, but it also results in less static thrust on the same RPM. This means a lot of times the MFG will put a higher KV motor on the fans with a lower blade count which will also give you a higher efflux speed.

What EDF do you have, it would be easier to advise knowing what you have.
 

flyfree

Member
IMO, it'll fly fine on a 6 blade 70mm EDF on 3s (thinking this is something like the Detrum fan ...). It'd be faster on 4s though. You'd probably want to stay around 2200-2600 mAh to keep the weight down.
 

SNAKE

New member
The EDF is a 70mm 6 blade with a QF 2827 3800 kv don't no to much about the fan, It was a package deal.
 

Namactual

Elite member
I did some searching and if that is the fan I think that is, the 3800kv is set up for 3s operation. The 4s is a 3500kv and 6s was 2300kv.

You should be fine on 3s.

Again, if that is the edf I think it is. The most important thing to take note of is how many watts/amps you are pulling and make sure you have a battery and ESC to match.
 

SNAKE

New member
Thanks, I'm sure glad that all of you are around, And know what you are doing, Makes it easy on everyone that don't really no.
 

SNAKE

New member
I am always around...

I can't say I always know what I am doing though.:unsure:
:p
I have a question for you? I'm going to reinforce the wing with a carbon fiber tube, would you use hot glue and reinforcing tape
or just use epoxy Thanks BILL
 

Namactual

Elite member
Hot glue and tape should be enough.

You said you have to cut the wing in half to fit your laser right? I would first tape the bottom of the seam and run a bead of hot glue between the wings. After it cures, tape the top as well. (look at the FT Cruiser build video at about the 2:45 mark, they do that on the Cruiser wing) here is a link...
Cruiser Build

As for the spar, just run a slot for your spar on the top of the wing and glue into place. Finish up by running a strip of packing tape along the spar on the top and bottom of the wing.

This would probably be overkill, but you would not have to worry about your wings folding.