Author Topic: Zilch Expendable Plan (Read 3613 times)

Steve Dwyer · « **on:** March 19, 2018, 08:52:52 PM »

Does anybody know where I can locate a Zilch Expendable plan? I can't get on to the Barry Baxter site any longer. Anyone with an old plan I'd be glad to pay for a copy.

Steve

George Albo · « **Reply #1 on:** March 19, 2018, 09:16:02 PM »

https://outerzone.co.uk/plan_details.asp?ID=888

wwwarbird · « **Reply #2 on:** March 19, 2018, 09:58:01 PM »

You might check with Walter Umland here on the forum, I'm pretty sure he kitted it at one time. If you could talk him into cutting you a kit that would be a huge bonus, you'll never find any better. This is Walter's vendor link...

https://stunthanger.com/smf/builtrightflyright-com/

Brent Williams · « **Reply #3 on:** March 20, 2018, 12:22:34 AM »

Here you go.

PDF of the Zilch X-Pendable plans is attached.

Tony Drago · « **Reply #4 on:** March 20, 2018, 12:58:22 AM »

I'd go with Walters plans. The are true to the kit. Landing gear is mounted it the wing as per the kit.
Better yet. Have Walter cut you a kit. I built one and it went together with out a hitch...

Roy DeCamara · « **Reply #5 on:** March 20, 2018, 01:20:24 AM »

The Zilch Expendable was kitted by Berkley and had the gear mounted in the wing. The Zilch-X was not kitted, but published in MAN. It is not the same as the Expendable. They are two similar models, but they are not the same. Walter kitted the Zilch-X. I am not aware of him kitting the Expendable. I built and flew Walters Zilch-X at the VSC four or five years ago. I built a Berkley Zilch Expendable back in the summer of 1954. The kit had a mahogany spar 3/8 inch square. The landing gear was one piece of wire and attached to the spar as I recollect. To long ago to remember, I still have the plans at home in WA. I'm still in AZ for the winter. Cheers...........Roy D.

Gerald Arana · « **Reply #6 on:** March 20, 2018, 09:09:59 AM »

Quote from: Brent Williams on March 20, 2018, 12:22:34 AM

Here you go.

PDF of the Zilch X-Pendable plans is attached.

I'd like to add that The X-Pendable was published in the October 1953 Air Trails magazine. It shows a fuse mounted LG which is the one that I choose to scratch build. Also an inverted engine can be used and is mentioned in the article. Here's a few pictures of mine which hasn't flown yet. (Crappy field conditions)
Those ribs don't go to the "X"....sorry

LE & TE are laminated. Fuse top deck is also laminated. My spar is 1" X 1/4" balsa capped with 1/16" spruce and is/was 2 oz's lighter than the 3/8" sq mahogany one (3oz's). Fuse is 3/32", ribs 1/16" and I choose to add 1/8" (tapered) to the LG so it didn't look so naked!

Tony Drago · « **Reply #7 on:** March 20, 2018, 03:03:21 PM »

Walters Zilch X-Pendable kit box

Steve Lotz · « **Reply #8 on:** March 25, 2018, 06:48:38 AM »

Can anyone report how they flew? They look awkward.

Steve

Roy DeCamara · « **Reply #9 on:** March 25, 2018, 10:46:27 PM »

Hey Ty..................I doubt Walter ever talked to Jim Saftig as he died somewhere around 1960! Not sure how old Walter is but I don't think he would be old enough. Cheers, Roy

Steve Dwyer · « **Reply #10 on:** March 30, 2018, 06:18:28 AM »

Gerald,

Thanks for the response to my request for the Zilch Expendable drawing, even thou I built the Expendable as a kid and wanted to do it again but I've decided on the Saftig Zilch X because of the larger wing and thicker airfoil. I want to invert the engine keeping the thrust line centered of course, yours has a much nicer appearance. Can you give me any feed back how yours flys? I'm concerned about the change in CG. I have also eliminated the full span hardwood spar going to balsa 1/4 x 3/8 top and bottom spars with blocking, sheeting the LE and adding cap strips. A photo is attached showing the wing on the bench. I've also increased to span by 2" because I wanted a 3 bay covered center section instead of only two. Still planning on a fox 35.

Steve

Gerald Arana · « **Reply #11 on:** March 30, 2018, 08:41:42 AM »

Quote from: Steve Dwyer on March 30, 2018, 06:18:28 AM

Gerald,

Thanks for the response to my request for the Zilch Expendable drawing, even thou I built the Expendable as a kid and wanted to do it again but I've decided on the Saftig Zilch X because of the larger wing and thicker airfoil. I want to invert the engine keeping the thrust line centered of course, yours has a much nicer appearance. Can you give me any feed back how yours flys? I'm concerned about the change in CG. I have also eliminated the full span hardwood spar going to balsa 1/4 x 3/8 top and bottom spars with blocking, sheeting the LE and adding cap strips. A photo is attached showing the wing on the bench. I've also increased to span by 2" because I wanted a 3 bay covered center section instead of only two. Still planning on a fox 35.

Steve

Hi Steve,

Actually, I haven't flown it yet! But according to Roy (Hi Bub!) they fly pretty good. I can't remember how the one I built waayyy back in '60 something flew with a Fox Rocket 35 and Hobby Poxy paint "Brushed" on (very heavy) flew.
Unfortunately it got left in the rafters when I got divorced...........('68) probably for the best!?

Jerry

Steve Dwyer · « **Reply #12 on:** March 31, 2018, 05:07:00 AM »

Jerry,

Can you tell me what tank you installed in your Zilch. I'd like to use a 4 oz but going thru the Brodak selections I can't find a tank that fits into the tight space with out widening and lengthening the fuse forward of the wing. Also did you go standard vent or uniflow? A pert number and dimensions would be appreciated. Please don't tell me you made your own.

Steve

Gerald Arana · « **Reply #13 on:** March 31, 2018, 01:25:00 PM »

Quote from: Steve Dwyer on March 31, 2018, 05:07:00 AM

Jerry,

Can you tell me what tank you installed in your Zilch. I'd like to use a 4 oz but going thru the Brodak selections I can't find a tank that fits into the tight space with out widening and lengthening the fuse forward of the wing. Also did you go standard vent or uniflow? A pert number and dimensions would be appreciated. Please don't tell me you made your own.

Steve

Steve,

It is a Brodak 3 oz. all tubes forward uniflow tank. And I have a very difficult time installing it with the "J" bolt LG connection. I actually had to make an 1" hole in the firewall for so the uniflow tubing could go into the backplate without a kink.....
I also have a magnetic hatch for servicing it. Works great...........so far!

Cheers, Jerry

Steve Dwyer · « **Reply #14 on:** March 31, 2018, 08:36:38 PM »

Jerry,
The 3 oz uniflow is about the largest that will work. Could you send some photos of the underside with the magnetic hatch removed.
Thanks,
Steve

Gerald Arana · « **Reply #15 on:** April 01, 2018, 09:18:20 AM »

Steve,

Here you go!

Cheers, Jerry

Steve Dwyer · « **Reply #16 on:** April 01, 2018, 04:13:34 PM »

Jerry,

Wow that's tight I guess I can make it work but I'd like to add 1/2" between tank bulkheads and add 1/2" to the length of the fuse, do you see a problem doing this?

Steve

Dan McEntee · « **Reply #17 on:** April 01, 2018, 07:24:39 PM »

Quote from: Steve Dwyer on April 01, 2018, 04:13:34 PM

Jerry,

Wow that's tight I guess I can make it work but I'd like to add 1/2" between tank bulkheads and add 1/2" to the length of the fuse, do you see a problem doing this?

Steve

If you are just sport flying, anything goes. But if you expect to fly this in Classic competition, you can not alter any nose moments or tail moments. You can alter construction for a custom tank, or rework the rear ply former and wing leading edge to allow the rear of the tank to extend further rearward. You can alter the engine bearers to allow a thicker tank also. An extra 1/4" above and below will add quite a bit of volume. Do a search on the forums here and some one else has already dealt with this, I'm sure. Just put some thought into it.
Type at you later,
Dan McEntee

Gerald Arana · « **Reply #18 on:** April 03, 2018, 09:31:55 AM »

Quote from: Dan McEntee on April 01, 2018, 07:24:39 PM

If you are just sport flying, anything goes. But if you expect to fly this in Classic competition, you can not alter any nose moments or tail moments. You can alter construction for a custom tank, or rework the rear ply former and wing leading edge to allow the rear of the tank to extend further rearward. You can alter the engine bearers to allow a thicker tank also. An extra 1/4" above and below will add quite a bit of volume. Do a search on the forums here and some one else has already dealt with this, I'm sure. Just put some thought into it.
Type at you later,
Dan McEntee

What Dan said...........

Jerry

Steve Dwyer · « **Reply #19 on:** July 07, 2018, 05:26:38 AM »

Jerry,
It occurred to me I never got back to you on my Zilch X status, I finished mine last month and flew it. I extended the rear of the fuse slightly installing the elevator horn inside the fuse as opposed to leaving it outside as in the plans. She came in slightly tail heavy, after installing some nose weight in the tank compartment it flew very nicely. I inverted the Fox 35.
Here's some pics, how was your first flight? PS I copied the paint scheme of another white Zilch I came across.
Steve

Gerald Arana · « **Reply #20 on:** July 07, 2018, 09:28:47 AM »

Quote from: Steve Dwyer on July 07, 2018, 05:26:38 AM

Jerry,
It occurred to me I never got back to you on my Zilch X status, I finished mine last month and flew it. I extended the rear of the fuse slightly installing the elevator horn inside the fuse as opposed to leaving it outside as in the plans. She came in slightly tail heavy, after installing some nose weight in the tank compartment it flew very nicely. I inverted the Fox 35.
Here's some pics, how was your first flight? PS I copied the paint scheme of another white Zilch I came across.
Steve

Hi Steve, I still haven't flown the X-pendable! The field I usually fly on isn't in the best shape, so I'm told, and I don't want to wreck it on the first flight....

Also, I've gone off on a tangent with (the dreaded) electric RC. I'll report back when I fly it.

Cheers, Jerry

PS: I like your color scheme on the "X"

Steve Dwyer · « **Reply #21 on:** July 07, 2018, 01:05:08 PM »

Thanks, keep me posted on the results once you fly it.

Steve