Author Topic: Semi-scale profile SBC 3 Helldiver (Read 15400 times)

Will Hinton · « **on:** November 30, 2013, 08:21:23 AM »

Okay, this will commit me to the build. (I know, I know, I should have been committed long ago; to a rubber room.)
In the middle 50's I built the Berkeley scale kit of the SBC 3 and loved the airplane, although I never really flew it! Don't have any idea what i did with it when I went in the Navy! (How do you lose an airplane?!)
I've intended to build another ever since, but had planned on a scale version. I decided the other day I should build a profile this winter to just bang around with on those new spring days so maybe flying a really simple airplane would get me fired back up to fly more.
Well, those who know me know I can't manage anything simple, that's too complicated for my twisted mind. (Figure THAT one out.)
The profile was going to be a warbird. Yup, then the idea of the Helldiver popped up and it was a "gogettem" thing at once.
The ship will be for one of my LA46's and will be planked foam wings coming in around 570 squares.
I love the Navy's paint schemes of the ships back then - the top of most top wings on the SBC were yellow with a chevron indicating the carrier the plane flew from by the color. The tail feathers were also each carrier's color, and there was a band of color (squadron) on the fuse. An air group commander had angled chevrons on the fuse from in front of the canopy angling down to just at the rear of the canopy. All in all, a very colorful airplane.
I'll post a picture here for an example, this is from my Squadron Publications manual of the SBC 3.
So, I am now committed and must answer to y'all for the steady construction. I'll try to not take as long as I did on the Pawnee!

55chevr · « **Reply #1 on:** November 30, 2013, 08:35:50 AM »

Will ... Looking forward to your build. Please post photos. I love the big WW2 combat a/c. Any one that can build a Berkeley kit can build anything.

Joe

Avaiojet · « **Reply #2 on:** November 30, 2013, 08:50:25 AM »

"Good" Will Hinton,

Nice!

Plenty of work ahead. Would you consider a built up fuselage? You will have the wing area for the extra minimal weight.

The span your interested in?

Charles

Will Hinton · « **Reply #3 on:** November 30, 2013, 09:32:11 AM »

Thanks guys. I'm doing a profile for now because of the build time of a profile verses the built up version. I still have intentions of building a full bodied scale ship later on. (My bucket list.) Gotta design a retract system first and foremost for that one. It will be a jack screw system.
Span on this one will be 38" top wing, 35" bottom. The motor mounts are curing as we type, then I Swiss cheese the fuse'.

55chevr · « **Reply #4 on:** November 30, 2013, 09:33:27 AM »

Will - build it to stunt ....

Joe

Will Hinton · « **Reply #5 on:** November 30, 2013, 03:29:27 PM »

Yeah Joe, that's the plan. My first bipe many years ago did a fairly decent pattern, at least for me as a rank beginner then, so I want this one to have those capabilities.
I'm presently planning the lead out adjuster design so I can adjust both rake and height until I get it right.
The other bipe, while flying well, hinged a lot. Al Rabe suggested his rudder, so I'm toying with that.
For anyone who might be interested, Al did an article in AAM feathuring mIne, Jack Sheeks', and Jean Pailet's biplanes as stunters. Jack's was a Beech Staggerwing, Jean's a Grumman Ag-Cat, and mine was a generic.
It was the June, 1973 edition and is on page 38

55chevr · « **Reply #6 on:** November 30, 2013, 04:15:59 PM »

I have an affection for biplanes. The Beech is flat out an ugly design. Same for an Ag Cat. The Hell Diver is a classic and was the state of the art in the 30-s. I also like the F3F and the Hawker Fury. Hoping you will post the build thread.

Joe

john e. holliday · « **Reply #7 on:** November 30, 2013, 05:34:10 PM »

Beauty is only in the eyes of the beholder. I have liked biplanes. One of the reasons that I built my version of Jack Sheeks Staggerwing. What a thrill to get a ride in one years ago.

Howard Rush · « **Reply #8 on:** November 30, 2013, 06:53:31 PM »

Quote from: Will Hinton on November 30, 2013, 08:21:23 AM

In the middle 50's I built the Berkeley scale kit of the SBC 3 and loved the airplane, although I never really flew it! Don't have any idea what i did with it when I went in the Navy! (How do you lose an airplane?!)

I had the Berkeley kit, too, and thought it was really cool. I don't know what happened to mine, either. This is mysterious.

Steve Helmick · « **Reply #9 on:** December 01, 2013, 01:43:01 PM »

Howard....I saw yours in your shop, last time I was there. I would have mentioned it, if I knew you were wondering where it went off to.

Steve

Howard Rush · « **Reply #10 on:** December 01, 2013, 02:16:07 PM »

You remember about where, and how deep?

Will Hinton · « **Reply #11 on:** December 01, 2013, 02:20:09 PM »

Quote from: Howard Rush on December 01, 2013, 02:16:07 PM

You remember about where, and how deep?

Oh my.

55chevr · « **Reply #12 on:** December 01, 2013, 06:03:39 PM »

Built from a Berkeley kit it might have withered and composted. They are just a box of thin sticks. My admiration to anyone that built them.
Joe

Douglas Ames · « **Reply #13 on:** December 01, 2013, 07:13:48 PM »

Quote from: Will Hinton on November 30, 2013, 09:32:11 AM

Thanks guys. I'm doing a profile for now because of the build time of a profile verses the built up version. I still have intentions of building a full bodied scale ship later on. (My bucket list.) Gotta design a retract system first and foremost for that one. It will be a jack screw system.
Span on this one will be 38" top wing, 35" bottom. The motor mounts are curing as we type, then I Swiss cheese the fuse'.

Oh, you mean Avaiojet holes?

Will Hinton · « **Reply #14 on:** December 02, 2013, 04:44:20 PM »

I'm not sure just what the immediately above post's intentions were, but I don't need to get into any of that sort of negative possibilities. It's unnecessary and provides no useful communications to this thread. So I hope you'll excuse me for sticking to what I consider mutually friendly posts, friendly to ALL.

55chevr · « **Reply #15 on:** December 02, 2013, 05:03:58 PM »

Will,
I agree. This is about you Helldiver.

Joe

Will Hinton · « **Reply #16 on:** December 05, 2013, 08:35:37 AM »

Found a little time away from other duties so worked on the fuse a bit. First picture is the bare nekked fuse with the carbon fiber cloth epoxied on both sides of the nose. I was out of ply, had always wanted to compare weight of this method verses the ply thing so went ahead and applied it. It's a medium weight cloth, spread the epoxy, put the cloth on and saturated it completely, heated it with the heat gun to make it flow out evenly, then used the old paper towel trick to soak up the excess.
I think the weight is very close to using ply, it's stiffer, and less likely to fuel soak or de-laminate.
Picture number 2 is the fuse ready for the "cut-and-no-paste" step to get rid of lottsa weight. I hope.
The next step, maybe even today, will be to block sand the fuse to a gently rounded shape before putting the 1/16th sheeting on over the formers. I want this to give the appearance of a built up, but stay skinny. we'll see if my hair-brained idea works.

55chevr · « **Reply #17 on:** December 05, 2013, 09:39:59 AM »

Cant tell from the photo but that does look nasty ... Did the surface smooth out?

Joe

Will Hinton · « **Reply #18 on:** December 05, 2013, 10:40:18 AM »

Hi Joe,
Yes, the surface actually had to be roughed up to get a good gluing surface after curing. When I lay the CF on, after I soak up the excess epoxy I cover it with wax paper and then weight it down with bags of #11 buckshot. I have a half bucket of "bad shot" not suitable for hand loading and I made several different size cloth bags up for it. It is great for laminating and such. Also for working with wings because the bags conform to the curvatures nicely. Since I have the opportunity here, I'm doing a lot of experimenting with things i've wondered about for some time. For instance, right now I have the outboard side balsa nose doubler curing with Gorilla glue on it.
I've never used it in that area before so now is a good time to learn.
I also, thanks to this forum, just made my first heat formed canopy. That works so neat! More on that later, I have another goofy idea for the "frame" on it.

Don Hutchinson AMA5402 · « **Reply #19 on:** December 05, 2013, 11:50:51 AM »

Nice subject! I have done similar with the Stearman and had a problem with one iteration I built from factory type drawings. The horizontal tail area on the real thing is not adequate for a model. Hope you have scaled yours to 22 or so %.
Don

Will Hinton · « **Reply #20 on:** December 05, 2013, 05:31:35 PM »

Don, I figured on 24% for the horizontal, split around 60/40 with the 40 being the stab. Does that sound close to you? I know your Stearman has been quite successful, so am most appreciative of any "steer" (pun not only intended, but unabashedly corny.) Thanks much.

Don Hutchinson AMA5402 · « **Reply #21 on:** December 05, 2013, 06:26:05 PM »

Excellent choice. My first two Stearmans were powered by a front rotor Ohlsson 23 and a Cameron 19. They were built by blowing up a rubber power plan from MAN in 1952. The next one was from the "factory drawings" and flew awful, then I realized rubber flyers enlarge their stabs to get them to fly well. The next bunch all had enlarged tail surfaces and worked good.

Mike Keville · « **Reply #22 on:** December 05, 2013, 06:56:37 PM »

Quote from: Don Hutchinson AMA5402 on December 05, 2013, 06:26:05 PM

"...The next bunch all had enlarged tail surfaces and worked good..."

===============================================================

Dang sure did!

john e. holliday · « **Reply #23 on:** December 06, 2013, 09:15:00 AM »

Hope yu remembered that when using Gorilla Glue that you put protection between the material you are clamping/pressing with. That glue will find every little hole and crack in whatever you are using. Even 1/4 in sheet balsa. Glad I use plastic clamps. And yet that first picture did look ugly.

Will Hinton · « **Reply #24 on:** December 06, 2013, 10:57:59 AM »

Yeah Doc, I use wax paper between my clamps and the subject. I use a few pints of GG a year in the guitar shop, so make every effort to preserve my clamps. When ya have some of these expensive clamps, ya gotta be careful or you end up VEEERRRRRY unhappy with yourself. (Do NOT ask me how I know that!!)
You mention it's propensity to fill every little gap, that's why I chose it for this particular area. I had a couple of spots I wasn't too happy with so I figured I would compensate with the old GG and take care of the little inaccuracy in that one spot. (Can you say extra weight?) I know, and promise to do better now.
Now, it's off to swiss cheese that fuse! Later.

Will Hinton · « **Reply #25 on:** December 06, 2013, 08:12:10 PM »

Well, they say confession is good for the soul, but in MY case it's also good for a laugh. (At my expense!) I got so carried away with designing "on the fly" that i neglected to allow for the bellcrank mount!!!! Now I gotta do some modifying just to keep it control line and not free flight!

I'll post a picture or two as soon as I learn how to transfer the jpegs from my new camera. My old Olympus is starting to protest so I'm giving up on her. She's earned her retirement!

Will Hinton · « **Reply #26 on:** December 07, 2013, 11:31:23 AM »

Okay, I'll try this picture thing again. It worked! Now if I can just remember how I decreased the size of the file!! I guess my new camera is TOO good.

This build is keeping me quite humble, I tell ya. While getting ready to mount the canopy I was blacking the area in with india ink and slipped up & spilled the ink on the fuse, what an ugly thing it is now! Doc, you think the raw CF looked bad, you just wait. (Actually, that looked so bad because I couldn't lighten up the image enough for you to see the details - it really wasn't so bad as all that.) And hard? Wow, I love the CF on the nose technique - it will become my standard for profiles.

The bellcrank mount is about cured and will come next, along with a tail wheel mount and I should be ready to skin the fuse about Monday.

Dennis Adamisin · « **Reply #27 on:** December 11, 2013, 05:29:12 PM »

WOW Will, it looks like you are SPEEDI BUILDING!

(and you know I am just teasin ya) GREAT subject, looking forward to seeing YOU and the Helldiver, and the crop duster all at the field next summer!

Will Hinton · « **Reply #28 on:** December 12, 2013, 08:53:43 AM »

Hey Dennis, I sure hope we can get together somewhere, some time!! Speed building? Well, maybe for ME!

I'm mounting the canopy now, hope to have it curing by the end of the day, then I can skin the fuse'.
I got my foam cutter back from Trax Tuesday, so can start on the wings right away. (The only two guitar builds I have are spec jobs, so no rush on them, which means I can PLAY!)

Will Hinton · « **Reply #29 on:** December 12, 2013, 08:00:16 PM »

I cut the top wing's three sections and joined them today. Boy, am I out of practice!!! got a lot of chatter on the two outboard sections, but since I plan to A) plank them and B) it's just a fun ship I will sand them smooth and live with them. They aren't all that bad, but I wouldn't build a PAMPA stunter with them. I won't core them since they are so thin, I'll just do the old combat wing-thing and pop a few holes in them after I get the trailing edge and spar installed.

Will Hinton · « **Reply #30 on:** December 14, 2013, 07:36:01 AM »

I started to install a spar in the top wing and discovered all my balsa supply in anything thicker than .070 is depleted! (Haven't been watching things closely enough, I guess.) So I tried an experiment - I sliced the wing where I want the spar to go and epoxied a strip of 6 oz carbon fiber cloth instead of balsa for a spar. Hey, this is such an ideal project for experimenting, dontcha think??
I mixed the epoxy with just a touch of alcohol (and I do mean a touch) to slow the cure a bit and make the brushing easier, clamped the beast in my bench clamp, did the messy part and then taped the LE in place to cure making sure all was straight and lined up properly. I'll sand the "spar" smooth after the curing is complete. Here's
a picture of the thing, and I purposely chose to not do a close up so ya can't see the cutting chatters!

Check out my balsa order over in the Open Forum, I found a new supplier that may turn out good, might not.

Will Hinton · « **Reply #31 on:** December 18, 2013, 05:04:24 PM »

Yesterday and today i got the LE and TE on both wings, sanded true and properly tapered. I also created wing skins with some 5lb stock for the lower wing and weighed out the skins sheets for the top wing. (Not joined yet.)
I cut the outboard fuse' side to shape from a sheet of the 6' wide iron balsa I got from the "new dealer". This will be one stiff fuse. I'm adding less than 2 oz. to the fuse for the skins and am pleased so far with this fuse construction technique. This is a very blocky and deep fuse, so could weigh in really heavy otherwise, especially since I have chosen to make it sort of sculpted, or curved a lot on the sides for more realism. Yeah, yeah, I know, realism for a profile Hinton? C'mon down to earth. Hey, gotta try it, right!?
It's getting a bit late, so no pics today, but as soon as I get a bit farther along I'll correct that.
I AM HAVING FUN!!!!!!!!!!!!!!!!!!!!!!!!!!!!

john e. holliday · « **Reply #32 on:** December 19, 2013, 08:44:37 AM »

Isn't that the most important thing, HAVING FUN?

Will Hinton · « **Reply #33 on:** December 19, 2013, 10:33:02 AM »

Sure nuff is, Doc! Your present project looks the same - fun! (Wouldn't be the top wing for a Ringmaster bipe, would it?)

Will Hinton · « **Reply #34 on:** December 21, 2013, 07:22:18 AM »

Thanks to Charles, I can now get these to post. He took my jpegs and showed me what values to use in scaling them down so the site would accept them THANKS CHARLES!!!!
Been able to work on the beast a bit. have the bottom wing ready for the tips, the top wing ready to plank, and the fuse skinned on the outboard side, ready to skin the inboard side. Here's some pics of the project so far.
I'm pleased with everything but the weight. I've used ALL 4-6 pound stuff except for the outboard fuse skin, but it just feels heavy.
I swiss cheesed the top wing as you'll see in the picture, that only dropped a quarter of an ounce from it. Phooey, I was hoping for double that.

Will Hinton · « **Reply #35 on:** December 21, 2013, 07:35:25 AM »

Top wing ready to plank.

Will Hinton · « **Reply #36 on:** December 21, 2013, 07:44:44 AM »

The fuse ready to skin the inboard with the outboard skin in place.
This shows the fat, stubby, fuse I like so well on this thing.
When I thought about the cowling being a separate color on the Navy's SBC's, I wanted some way for that to stand out, so I soaked a piece of 1/16th and molded it around the front of the fuse to try and accomplish that. I think it's going to work, so I'm happy with it for now. We'll see what it looks like with color.
I'll see if I can post two pics at a time here.

MarcusCordeiro · « **Reply #37 on:** December 22, 2013, 10:09:07 AM »

Looking good!!!!

Marcus

Will Hinton · « **Reply #38 on:** December 23, 2013, 09:04:18 AM »

Thanks Marcus, and how is your current project coming along?

Will Hinton · « **Reply #39 on:** December 23, 2013, 04:30:55 PM »

Things are moving along here - both wings are planked and ready for the tips, but I think I'll make the connecting struts first. They aren't "N" type struts at the tips, and that makes it really a cinch to get the wings aligned properly incidence wise. (I would have had those made, but the weather today was rather mild so I spent time in the outer shop shaping a bass neck.)

MarcusCordeiro · « **Reply #40 on:** December 23, 2013, 05:12:54 PM »

Will

It's, ups, they are coming along pretty well. Behind schedule, even when there's no schedule...

Looking forward to seeing yours with some colors.
It's a cool build.

Marcus

Avaiojet · « **Reply #41 on:** December 23, 2013, 05:30:43 PM »

"Good" Will Hinton,

Alakazam!!

WOW! Like magic, how fast you're moving on this build. Super kudos!

Ya know "Good," generally I don't get excited over builds, not even my own, but I gotta tell ya, this is EXCITING!!

In my case, it's the choice of the aircraft your modeling, a bi-plane, a Warbird, loads of color! Great!

You have my interest. To late to build two?

Hey Good, psst, come a bit closer, I don't want anyone to hear this. Careful how you use the word "planking," I got in a bit of trouble with that, remember?

Hey! I've got your back, when the time comes for lettering and graphics, as usual, so give it no concern. Colored vinyl or spray masks whatever it takes.

A Christmas "gift" when your ready. Also for being an exceptional modeler.

BTW. Nice photos.

Charles

Don Hutchinson AMA5402 · « **Reply #42 on:** December 23, 2013, 07:04:06 PM »

Will-
You mentioned the wing struts. My experience with the Stearman was that it tended to rock a bit in the roll axis because it is such a short distance from the fuselage to the struts. If you can "cheat" the struts out toward the tips a bit without exceeding your own sense of scale it might be worth doing.
Don

Will Hinton · « **Reply #43 on:** December 23, 2013, 08:28:13 PM »

Thanks Don, I guess, as Tom Neuber said, great minds think alike. Because of the leadout guide I planned on the struts being as close to the tips as possible. My successful bipe back in the 60's did the same thing you just talked about so this one will be out there, annnndd...they won't be angled between the wings either - straight up and down for simplicity and to be able to move the LO guides as needed without adding another dimension to the move. That's a section of the build where I have some trepidation for the LO placements in the end. I have the strut planned so I can change the initial offering for the guide once the right position is established through flying.
I really appreciate your help with this project, Don, because you have a lot of research behind you that I can use! Thanks much!
And merry Christmas, guys!!

Will Hinton · « **Reply #44 on:** December 29, 2013, 08:06:49 PM »

I made a little progress today, and I do mean a little. But, I was able to get the wings sanded and ready for the tips and make the main struts. I couldn't resist doing a trial fit of the wings and fuse, so here are a couple of teasers.

MarcusCordeiro · « **Reply #45 on:** December 30, 2013, 07:13:31 AM »

Marcus

john e. holliday · « **Reply #46 on:** December 30, 2013, 09:36:55 AM »

That is looking great, but where's the pilot? Just kidding as I don't do pilots either.

Will Hinton · « **Reply #47 on:** December 30, 2013, 10:03:37 AM »

Doc, I spent a horrible amount of time online looking for a good profile picture of an early WWII pilot bust i could print out and glue to a piece of 1/16th ply backing so i could have the two pilots in it. No luck, now someone here will probably find me one and it's just too late. Drat.

55chevr · « **Reply #48 on:** December 30, 2013, 10:34:34 AM »

I don't do pilots ... I think of it as being about modeling airplanes.

Serge_Krauss · « **Reply #49 on:** December 30, 2013, 03:10:18 PM »

Will, I'm more and more intrigued! This should be an interesting plane to fly! Keep at it!

SK