Sig Super Chipmunk

[Neville Legg]

Is that a SIG Chipmunk, Paul? The tail moment looks a lot longer than the Kit!

Cheers       Neville

[Paul Taylor]

Hey Neville,
I am not real sure. Some one gave me this plane, and he got it from an estate. I posted a few photos when I got it asking about it and several people ID it as a Chipmunk.

Maybe when I dig into it, there we be something stamped on a rib or some plane on the bones that will tell me what it is for sure. I got a Sig Akrobat as well, and the ribs are marked as Akrobat.
The Chipmunk did not have a plastic cowl, but the Akrobat did.

[Alan Hahn]

I believe that is the first Sig Chipmunk kit, aka a "Van Loo" Chipmunk. The current kit is the "Super Chipmunk".

Mike Gretz gave a really nice history of the Sig Chipmunk genealogy.

I know there was a link on SSW, but maybe here too.


I found the link to a web page, but unfortunately the page seems to have vanished into the "ether". I'll post Mile G's. article- I note that this there seemed to be a link from Phil Brown's (aka Garf) CL Links site, but I don't find it anymore (it may have been to the now non-existent site also pointed at by SSW.

The top link (the pdf file) is Mike G's genealogy. The jpgs are the MAN article on the vanLoo Chipmunk.

[Brian Massey]

Dave Fitzgerald lengthed the tail moment of his Chips by 3 inches. So maybe . . .

Brian

[Walter Hicks]

Chipmunk Mods :

1. Equal panel wings


2. Flap to elevator hingline  , lengthen  3"

3.Stab/Elevator  is I believe 1" longer .

4. Keep weight below 50 Oz.


5. Use La .46 or St .46


YES the mods make it a  MUCH better flying airplane , I have build  4 Chipmunks  the last being with the mods.

Dave Fitz  used this is his younger days!

[Alan Hahn]

Chipmunk Mods :

1. Equal panel wings


2. Flap to elevator hingline  , lengthen  3"

3.Stab/Elevator  is I believe 1" longer .

4. Keep weight below 50 Oz.


5. Use La .46 or St .46


YES the mods make it a  MUCH better flying airplane , I have build  4 Chipmunks  the last being with the mods.

Dave Fitz  used this is his younger days!

I wonder if Dave F. read Ted Fancher's Twister modifications----3 inches added to fuse length sounds familiar! Also helps balance a heavier engine.

[Clint Ormosen]

Dave Fitzpatrick lengthed the tail moment of his Chips by 3 inches. So maybe . . .

Brian

Brian, ya' might want to fix that typo.

[Richard Grogan]

Richard, your Chipmunk looks fantastic, but where is the pilot man??? you have to have a pilot If you're going to have a glasshouse you need a pilot!



Cheers      Neville

Neville,when he found out that I was the one who was actually going to be in control, he jumped off my bench and hid himself in the "grey area" of the shop. Haven't seen him since...can't say that I don't blame him! 

[Neville Legg]

Richard, I find pilots all over my workshop! probably doing what yours did?   I normally sit them down, and give them a good talking to, and tell them its not that bad a job. By this time my wife is reaching for the phone, to call for the men in white coats They normally live to fly the next model, I have some from the '60's, though when my Sheeks Spitfire bit the dust after the elevator horn broke, I never did find the pilot, that flying site is now a housing estate, so I hope he got a decent burial! Got to go, the men in white coats are knocking on the door! 


Cheers            Neville

[Brian Massey]

Brian, ya' might want to fix that typo.

Lengthened/lengthed; potato/potahto. I was once married to a "Professor of English" . . . she couldn't teach me much either. 

When I remember to use it, I find spell check very helpful. 

Brian

[Balsa Butcher]

Clint may have been referring to the spelling of Dave Fitzgerald's last name...oops!  

[Brian Massey]

Clint may have been referring to the spelling of Dave Fitzgerald's last name...oops!  

Drat! I did it again!    Back in '05 I chaired the Pontiac/Oakland Western Regional Convention. One of our guest speakers was Art Fitz (drum roll please) patrick! We became pretty good friends and now every time a name starts with "Fitz", guess what I say . . . To further befuddle my brain, he also goes by "Fitz".

If you like automotive art, you should check him out. He did all the great Pontiac ads from the 60's when they were all hand drawn. He also designed the sports car stamps from 2005 (which out sold the Disney stamps) and more recently consulted on the Disney movie Cars. www.fitz-art.com

My apologies to the "other" Fitz. 

Brian

[Clint Ormosen]

Clint may have been referring to the spelling of Dave Fitzgerald's last name...oops!  

Now you got it.

[Brian Massey]

Now you got it.

I may not be fast, but sometimes I'm not as slow. 

Brian

[Brian Massey]

The Flyin' "Fitz" says to bring in a Chip at 50 ounces! Gads, what am I doing wrong! All the "parts" collectively weigh 47.2 ounces now, with no finishing work applied!  That's the wing, fuse, stab/elevator/rudder, B40 with prop and muffler. I still have to add landing gear, covering, dope etc, etc. Am I building a pig?

I know I've added extra bracing around the tip weight box and bellcrank platform, but certainly not measured in the pounds. I'm using all the stock kit wood, could that vs. contest grade make that much difference???

Brian

[Clint Ormosen]

Brian, let me start off by saying that your woodwork it excellent. However, the weight is a major concern. Depending on the rest of the finish work and hardware, you could be looking at a near 60 oz Chipmunk. That's a problem. Start looking at ways to trim this thing down. You might need to rebuild the stab/elev assembly with lighter wood. Trim the center of the ribs out. Same with fuse assembly. Maybe re-sheet the fuse top. Anything you can do to cut weight.

Come on guys, let's help him out with more ideas!

[Brian Massey]

AARRRRGGGGG!  When I totaled the individual weights I included both the wing with flaps, and wing without flaps weighs!! 

The correct skeletal weight is 35.3 oz.  I feel much better, but a bit more stupid. I may be on target for that 50 or so ounce Chip. 

Brian

[Balsa Butcher]

You need to weight ALL the parts - LG, fuel tank, wheels etc. as well as the skeleton to get a realistic figure. In other words, everything but the paint. Plan for 8-10 ounces for the finish. I'd use monokote or Ultra-kote on the wing. Many Chips are finished that way and it is a lighter finish than a full-on dope paint job.  

[Alan Hahn]

You need to weight ALL the parts - LG, fuel tank, wheels etc. as well as the skeleton to get a realistic figure. In other words, everything but the paint. Plan for 8-10 ounces for the finish. I'd use monokote or Ultra-kote on the wing. Many Chips are finished that way. 

I think John Paris's Super Chipmunk has a Monocote/Ultracote covering with paint for the sunburst pattern, and he regularly cleans people's clocks with it at the Sig Contest.

I think the B40 is a great choice for a liteweight but powerful engine for the Super Chippy.

[Terrence Durrill]

I started a Sig Super Chip about 1987 and hope to finish it some day soon.  Seems like everyone recommends lots of power and I do not own any 40's or 46's.  I do have a new Fox .35 with balanced crank, stuffer backplate, Marvin Denny's hemi-head and a Super Tigre needle valve assembly.  I also have several O.S. Max .35S stunt engines in very good condition, two Veco .35's series 100, in very good condition and some McCoy 35 Redheads.  This Chip will be built completely stock, using all kit parts.  The kit itself, was purchased from a local hobby shop about 1984.  Any suggestions would be appreciated.  Thanks....TDurrill   

[Alan Hahn]

I'm guessing that if you can keep it light, (in other words, watch out for the plastic parts), and I would think about plastic covering, to keep the weight ALARA (As Low As Reasonably Achievable). Of what you have, I'd go with the OS35S. I believe it's bit more power than the Fox 35 but not a lot more weight.

The kit moments are set up (I believe) for the Fox 35--probably without a muffler, so the 35S (which isn't that much heavier) isn't a bad choice. However see if you can find a light muffler to strap on. Every bit helps!

I have a Super Chipmunk, and several 35's and two B 40's (plus a fair # of Fox 35's). I think I'll go for my B40, or maybe electric!. But it is important to watch the overall weight.

[John Paris]

I think John Paris's Super Chipmunk has a Monocote/Ultracote covering with paint for the sunburst pattern, and he regularly cleans people's clocks with it at the Sig Contest.

I think the B40 is a great choice for a liteweight but powerful engine for the Super Chippy.

Alan,
Mine is silkspan and dope.  I think in the early days it was around 44-46 ozs but is closer to the 50 mark now.  There is another on the board now with the same paint scheme in mind.  I will use my DS 40 in it just like the old one.  Hopefully it won't have to work as hard with the new one.
John

[Alan Hahn]

I think the DS40 and B40 are about the same weight (almost identical engine with regard to weight).

Sorry to think your's was plastic. But with silkspan, I try to keep at least 10 feet away just in case I might drop something!

[Brian Massey]

Here is a letter written by Dave Fitzgerald to Walter Hicks (one of our club members) regarding the mods Dave made to his Chips. These changes took a great flyer and elevated it to championship level (Not that Dave's expertise had anything to do with it  . So with great thanks to Dave and Walter . . .

I've had to resample the scans down to get them to load here. If you want the full res scans (about 3.6 megs) let me know and I will be happy to email them to you.

Brian

[Alan Hahn]

Brian,
Thanks for posting the notes (and thanks to Dave F. for making them!).

He mentions sanding the cowl down to fit the narrower fuse, but my guess is that this isn't the plastic cowl in the Super CHipmunk.

[john e. holliday]

Looking at the pictures, he has a couple of ounces that can still be removed from the ribs.  When I get done with a set of kit ribs they resemble an I-Beam rib.  Also sand all sheet wood before using or punching out parts.  Looks good so far.

[Brian Massey]

Good idea Doc; I've never sanded the sheets prior to removing parts.

Thanks,

Brian

[John Paris]

Brian,
Thanks for posting the notes (and thanks to Dave F. for making them!).

He mentions sanding the cowl down to fit the narrower fuse, but my guess is that this isn't the plastic cowl in the Super CHipmunk.

Alan,
He is probably talking about sanding the two pieces a bit before joining.  That would make the overall assembly thinner to fit the new fuse design.
John

[Luiz Dutra]

Hi Brian,
Very nice kit. Must replace the abs cowl/wheel pants for fiberglass parts. I finished one last year with monokote. Total weight is 42.5 oz with the Randy Smith Fox .35. Luiz- Mococa/Sp - Brasil

[Brian Massey]

Hi Luis; Very Pretty Chip you built! I hope mine comes out half that nice. I'm planning on a Brodak .40 for power, silk and dope finish and a flying weight around 50 oz. I'm considering balsa wheel pants and cowl, not sure yet.

Your paint scheme reminds me of Tom Warden's Continental . . . was that on purpose?

Brian

[Brian Massey]

Thanks Ty, that's another good tip. I may go in with the dremel and shave a gram or two.

Brian

[Shultzie]

Neva'nuff Chipmunk photos

[john e. holliday]

If I remember right, that is a father-son photo of the McClellen's.  Hope he is doing better.

[Shultzie]

If I remember right, that is a father-son photo of the McClellen's.  Hope he is doing better.

Yes...That is the McC Clan!

(hope he is doing better?) Uhhh? Tell us more?
They were great modelers and great modeling friends...and made our CLPA world a betta' place.

[john e. holliday]

I heard he had to give up the Chairmanship of the aerobatic contest rules board because of ill health.  If I remember right someone said something about heart troubles.  Maybe Keith Trostle will chime in on this. 

[Jim Pollock]

Regarding Dave Fitzgerald's mods to the Chipmunk.

He tells me now that if he were building one today,(2010) he would build it box stock but power it with a PA .40UL
I think he's figured out that 75% of a planes flying ability is due to it's engine.  Guess that's why he's using
a PA .75 in a 630 Sq In Plane.

Jim Pollock   

[Shultzie]

Still neva-nuff Chippy's....
Except for Bob Welch's beautiful winning Chipmunk here in the NW in the mid 70's and early 80's...this beautfull Super Chip by Bob Suoboda who place 13th at the 72 Nats rates WAAAY up there on the best of the best Chipmunkity list.
(This great shot was by Les McDonald's slide collection)

[Brian Massey]

Here's a status update on my Chip: The basic airframe is together; fillets are almost done; tail wheel mount is on; drilled and fitted for tank and engine and the controls hooked up and covered . . . I hope this last step was not premature.

So far the weights are:

Airframe: 26.8 oz (Bottom of fuse and cockpit are sheeted and fillets on in, along with some filling.)
Engine/muffler/prop: 10.5
Accessories: 7.2 (Included in this are the tank with tubes, vents and mounts; cowling; wheel pants; engine mounting bolts/washers etc and tail wheel.)

Total weight is now at 44.5 oz. with a silk and dope finish yet to be added. I think the dream of a 50oz Chip are doomed,  perhaps 55oz is still in reach.

Neville, is yours started yet? If you have any problems/questions, just ask, I've probably made most of the mistakes possible. 

Brian

[Walter Hicks]

Brian,

  This is what happens when you use the kit wood. The 50 oz or less  can only be accomplished by using contest wood.  The only wood I would use are the wing ribs! Or by carefully weighing each part and if it is light keep it.

[Richard Grogan]

Brian,
As a last resort, you can lose the wheel pants. If you must have pants, try to make some vacuform ones out of lite plastic. Use Dave Brown or du-bro lite wheels(foam).Cut some lightening holes where you can, not to affect any structural points, of course! Should be a great flyer anyhow. It may be happier a little overweight, kinda' like GMA's Noblers that I've read about here!I shamefully cover mine with Ultrakote and used LusterKote for the colors.While not a World Beater, I love mine. 

[Neville Legg]

Brian, your Chipmunk is looking good! I haven't started mine yet, I've spent the last month trying to get over pneumonia, either in bed or sat in front of the fire trying to feel better, reading old Aero Modeler mags, and trying to get my enthusiasm back My mind is full of enthusiasm, but the body is so weak   It'll get better soon I hope?
Have you gone over your model with the sandpaper again? Like sanding the flaps, elevators, tail, fin and rudder to proper aerofoil sections. It can reduce the weight of these components by almost half ? Have you read Don Bambricks article on finishing his Fury in Flying Models, I think he got the finish down to a few ounces! Its all in the sanding, and preparation, apparently!  Look forward to seeing it finished.

Cheers       Neville

[Chris McMillin]

Still neva-nuff Chippy's....
Except for Bob Welch's beautiful winning Chipmunk here in the NW in the mid 70's and early 80's...this beautfull Super Chip by Bob Suoboda who place 13th at the 72 Nats rates WAAAY up there on the best of the best Chipmunkity list.
(This great shot was by Les McDonald's slide collection)

One of the best looking Chipmunks I've ever seen. One can see the results of what is called "shaping" done with wood tools from Xacto tools and sandpaper around the fuselage and cowling! The little 1 1/2 inch spinner is simply elegant.
Thanks for the picture Don, and Les.
Chris...

[Brian Massey]

Brian,

  This is what happens when you use the kit wood. The 50 oz or less can only be accomplished by using contest wood.  The only wood I would use are the wing ribs! Or by carefully weighing each part and if it is light keep it.

You're right Walter; this is 100% kit wood. I decided to go all kit wood and make no real modifications. My plan is to make another from scratch using hand selected wood (This is one of the reasons I'm weighing this one so often.), and making some modifications. I want to see what differences I can tell between the two. I love the looks of the plane so won't mind having two.

[Jim Pollock]

Just a note here:

The paint scheme you have called a copy of Tom Warden's Continental is actually the paint scheme that Art Scholl used on his Chipmunk.  I still don't think anyone has figured out the reason for the stabalizer separation from his plane that resulted in his all too untimely death.  Every plane I see with that scheme, I consider it to be a tribute to one of the very best acrobatic pilots ever to step into a cockpit.

Jim Pollock      

[Balsa Butcher]

A long time ago Tom Dixon wrote an article about re-visiting the Chipmunk kit. He built it with the kit wood, mono-koted the wings and painted the rest with a dope based sport finished. I don't remember what the finished weight with but he was very happy with the way the finished airplane flew. I'd still consider carving the wheel pants out of light balsa or ommiting them altogether to save an ounce or two. Otherwise fly and enjoy, fortunately the Chipmunk wing is capable of flying a less than super-light airframe well. 

[Brian Massey]

Just a note here:

The paint scheme you have called a copy of Tom Warden's Continental is actually the paint scheme that Art Scholl used on his Chipmunk.  I still don't think anyone has figured out the reason for the stabalizer separation from his plane that resulted in his all too untimely death.  Every plane I see with that scheme, I consider it to be a tribute to one of the very best acrobatic pilots ever to step into a cockpit.

Jim Pollock      

Thanks for jogging my memory; I have gotten so use to seeing the paint scheme on the Sig box I forgot. I wonder if Tom Warden liked the paint scheme and took his ideas from there? If you haven't seen Art's flying in awhile, here's an old video of him in his Chipmonk performing the lomcevak.

The pic is Tom Warden with his Trophy Trainer. Same paint scheme that he used on his Continental.

Brian

[Brian Massey]

I hope "better late than never" works on model diets.

Brian

[Gary Dowler]

Ok, so here is one of those questions about the Super Chipmunk Kit that might seem utterly, inexplicably, simple to most. But sometimes things look one way and end up being another.

Started this kit. Built one in 1983, but I don’t recall how I answered this question. If you look at the picture of the fuselage side, you see the wing cut out.  There is a solid line, and at front a dotted line. The instructions offer nothing whatever in the way of explaining which to cut on.   

On a profile ship, where maximum wing chord on a tapered LE is in the center of a 1/2” piece of wood, obviously you cut to maximum size.  On a full fuselage, am I correctly assuming that you cut on the solid line, and the dotted line indicates maximum chord hidden in the middle?

I know this sounds silly, but I don’t want to cut this until this question is resolved.  A simple notation in the plans would have gone a long way here.

Gary

[Gary Mondry]

Gary,

From the Sig "Super Chipmunk Building and Flying Instructions" booklet, basic fuselage construction "Cut the fuselage sides out of the 1/8" printed balsa sheets.  Note that there is a right and a left side.  On one side cut to the dotted line at the front of the wing cutout.  This will later allow the wing to be inserted into the fuselage."  Then in Final Assembly, "The leading edge of the opening on one fuselage side must be opened up to the dotted line to allow room for the center of the wing to slide by."  And also "(Note alternate wing installation method described on the plan which is preferred by many modelers.)"  I don't have the plans, but believe the alternate method is to cut the fuselage out beneath the wing to allow it to be installed, in which case the cutout wouldn't need to be enlarged on one side.

I hope that helps.

Gary

[Gary Dowler]

Gary, thank you. That answers everything.  Given that this kit is probably 35+ years old, the more recent instruction book isn’t there.  Thanks again.

Gary