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Indoor Free Flight Forum => Completed Builds No-Cal => Topic started by: Broken Strands on June 21, 2008, 06:43:27 PM



Title: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 21, 2008, 06:43:27 PM
I'd been thinking about building a no-cal model of some sort for a few weeks and was trying to decide on which plane. Last Sunday I was looking through the threads created by outofbalance and found a link to Paul Bradley's site (thanks OOB). Paul's got about a dozen no-cal warbirds plans available for download along with color graphics for each design! I got all excited and printed out a set of plans for the Hellcat and printed out a set of inked-tissue graphics at the same time.

Here's what I have so far, the prop blades are cooking in the oven right now. Notice my first attempt at a rolled balsa tube in over 25 years (to the right side of the first pic) didn't turn out so good :-[. I may go with a carefully picked out solid stick for now just to get this done. Hopefully by tomorrow...

Bill


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 21, 2008, 06:49:41 PM
One of the items that did turn out well however was the bearing and prop shaft assembly. I copied the well-proven Ray Harlan type out of a sheet of .030" aluminum. From front to back it's 1/2" long and .093" wide, the wire used is .020"


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 21, 2008, 06:58:10 PM
As it turns I'm all but genetically incapable of accurately and consistently forming wet balsa using a hot soldering iron. I had to resort to forms and laminated outlines, all the outlines are 1/32"X1/16" (2 layers). In this case the old dog couldn't learn a new trick.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Mike Taylor on June 22, 2008, 02:56:01 PM
I think you'll be happy with how strong and light the laminations turn out to be. Guys I fly with indoors are making those as electric R/C models ; they fly great and look great in the air...


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 22, 2008, 11:05:05 PM
I think you're absolutely right about the laminated outlines Mike. One of these days I will have to sit down with a handful of balsa sticks and teach myself the soldering iron technique. Right now I'm too anxious to get this Hellcat finished.

Also, the thought of micro R/C in one of these little planes sounds very interesting! Trying to resist spending more money...

Here's a set of tail feathers for a 24" WW2 Lavochkin LA-7 mass launch plane. Curved outlines certainly are cool.

Bill


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 22, 2008, 11:22:43 PM
Covering the fuse and stab presented no major problems, they're both flat. Did have a concern about how I would attach the inked tissue, the ink from my printer will smudge with moisture. Ended up using the recommended Uhu glue stick, another technique I have little to no experience with. For some reason my tissue (Esaki) doesn't want to stick my wood (balsa) very well. Either my glue is too old and stale or I'm too slow in getting the tissue in position and stuck down, both likely conditions.

I ended up using the glue stick to tack the tissue into place then followed up with a 50/50 mix of white glue and water to finally seal the piece, so far so good. Smudging was minimal.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 22, 2008, 11:29:09 PM
Here's what I ended up using for a motorstick. A piece of 1/32"x1/4" glued to a piece of 3/32"x3/16" to form a "T" cross section. Not as fancy as a rolled motorstick but should prove adequate... and was much simpler to construct!


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Dan G. on June 22, 2008, 11:40:09 PM
Very pretty Lavochkin pieces.

Dan G.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Mike Taylor on June 23, 2008, 11:12:07 PM
Bill, I agree with Dan, gorgeous framework. That will look so cool floating overhead...


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 23, 2008, 11:30:27 PM
Thanks Fellas, it means a lot coming from you guys. I've seen the quality planes you both produce.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 23, 2008, 11:39:33 PM
Tried to figure out a methodical way to cover the wing, taking into account all the limitations of water soluble, inked tissue that ultimately can't be shrunk... intentionally or otherwise. I could have covered the whole thing flat then prop up the tips and glued but that method would leave huge folds at each of the dihedral joints. Remember, this is a Hellcat so it's a three-panel wing with a flat center section.

Decided on the most tedious procedure. Doing it the proper way always seems to take the most time and effort. The pics should tell the story.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 23, 2008, 11:49:35 PM
A trick I learned many years ago was used again with very satisfying results. Right before attaching each of the tissue pieces I ironed them to force all the moisture out. This shrinks the piece down to it's smallest dimension, in theory anyway, so that when the piece is attached it will never shrink-up more when the humidity drops warping your delicate structure. I'm also happy to report that the ironing process didn't smudge the ink. I ironed with the ink side down.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 23, 2008, 11:54:25 PM
Getting close now! Forced myself to make a specialized sanding tool to cafefully open up the slots for the wing and stab. It's just a piece of 220 glued to a piece of 1/64 ply. Worked great!


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 24, 2008, 12:00:02 AM
Put the whole thing on my cheapie scale and ,Wow!, very happy and surprised. 2 1/2 grams! I was hoping for around 4. Sometimes things work out after all.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 24, 2008, 12:09:18 AM
Had to modify the TE of the prop blades so they would clear the "massive" engine cowl. I'll let you guys know how it flies.

Bill


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 24, 2008, 12:13:03 AM
Here's a shot where I forgot to turn on the flash. Turned out kind of artsy fartsy with the twilight shining through the window.

Next plane... Bearcat!


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: lemuel on June 24, 2008, 12:33:48 AM
that looks fantastic broken strands.. how do you stop the tissue from twisting the frame? Do you iron it? or pre shrink it first and then iron it and then print on it? i like no cals but have had no luck with the warping thing. What is the span that these things are supposed to be again?

regards
Matthew


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Dan G. on June 24, 2008, 01:44:41 AM
Man ... that looks really good ... should get some pretty good times, too.

I have to say ... printers have certainly revolutionized the covering and finishing ... who would have thought?

Dan G.


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 24, 2008, 01:45:51 AM
Hi Matthew, I've tried several methods in the past to control shrinkage, pre shrinking on a frame, wadding the tissue into a ball then smoothing out etc. Now I simply iron it, not so much to smooth out the wrinkles but to force as much moisture out as possible right before attaching the tissue to the plane. This is for planes intended to have a loose tissue covering. For planes that have a more robust structure where the covering will be taught I do no prep at all on the tissue.

Here's where I got the plans, http://www.parmodels.com/Plans/nocals.htm

As far as I know the WS limit for no-cals is 16"

Regards, Bill


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: lemuel on June 24, 2008, 01:51:04 AM
thanks Broken strands, I think i might shoot the idea around to the boys so that we can have a no cal flying thing going in the local gym.

regards
Matthew


Title: Re: No-Cal F6F-3 Hellcat -Build-
Post by: Broken Strands on June 24, 2008, 01:54:31 AM
Hi Dan, ain't these little things a kick in the head? I dismissed these things as beginner planes for years, then I heard some guys getting 5 and 6 minutes with them and that really raised my curiosity. Now, after building one I'd say they're about as delicate as a PennyPlane with the flight performance of a Bostonian. They're actually an indoor duration plane that just happens to look kinda scale!