My New First Big Bird...

[Chancey Chorney]

Hi all. I am at a kind of happy place right now. While cruising our local version of Craigslist, I came across a gentleman that was selling all of his RC stuff. Amongst them, one plane caught my eye. It was a Sig Twister. So, I made a call, and he wanted to sell it all as a 'Lot', for the low sum of $1500 CAD!  He did NOT want to separate the package, but invited me down to take a look anyway and told me if the stuff didn't sell in a few weeks, he would consider selling it to me. So I showed up to take a look in case he was to split it up later. I was very happy to see the plane, and it did indeed look nice. All dope and fabric (cannot remember what he told me he used, but it was not silkspan), new never run Fox .35 50th Anniversary Edition, new .15 x 60 foot lines, and new Sullivan handle. As I admired it, he was telling me he had never flown any of his planes, the RC stuff or this Twister. Only built and hung up. He wanted to talk a bit so I listened to him. After I thanked him for the time and allowing me to come out and see his stuff, he offered me to buy the Twister as pictured with the accessorises mentioned. I think I paid a bit too much (but was saving up for something like this), but now have a nice plane to fly with only a few things to fix. Mainly the flaps and elevators as he has used over-under cloth hinges and they feel too stiff to me, but he said they were installed as per the plans (which he did no longer have). So, please enjoy the picture of my new toy!

[Steve Helmick]

Cloth hinges will usually loosen up with some wiggling and suitable vibrations, which will probably be abundant with the Fox .35.

Oh yeah...we need to see the pictures. You forgot them, didja?  Steve

[Chancey Chorney]

Oops, forgot the picture.
And also, would anybody here happen to have a digital copy of the Sig Twister plans they would be able to share? I had a set before on my computer before it crashed and I lost everything and could not remember where I had gotten it from. I would like these in case I have to repair or rebuild something in the future. Thanks again.

[Steve Helmick]

All I've got is the Fancherized Twister plans. It should help, anyway. It may be on Outerzone?    Steve

[Chancey Chorney]

Thank you. Anything is better than nothing.

[Tim Wescott]

Whuzzit weigh?  I'm a bit concerned that he may have used Super Coverite or something else heavy.  The Fox 35 likes things light.

The Fancherized Twister plans should have the information you need for repairs -- really, all you need is the rib profile and in a pinch you can get that from the ribs themselves.

Keep us posted.  Remember that the Fox 35 wants lots of oil, and most of it castor -- see if you can find a "what should I run in my Fox 35" thread someplace.

[Russell Shaffer]

You might need to put a brace on the elevator pushrod.  I don't see one and the wire will often flex.  I'm sure you plan to remove the engine from the plane and bench run it for a bit?  The airplane looks to be very well built and you can't go wrong with all of the new stuff that came with it.  Best of luck and have fun with your new bird.

[Chancey Chorney]

Thanks all for the tips. I will look into a support for the controls. I will be calling around to see if I can find some castor around here, as I have only Omega fuel available locally!

Weight as pictured is 2 lbs 3.6 oz., or 35.6267 ounces.

[Tim Wescott]

Thanks all for the tips. I will look into a support for the controls. I will be calling around to see if I can find some castor around here, as I have only Omega fuel available locally!

Weight as pictured is 2 lbs 3.6 oz., or 35.6267 ounces.

Check with motorcycle shops.  IIRC the lubricants available are castor-based and way expensive, but aren't pure castor.

If you get desperate, modern hippy-dippy cosmetics places sell castor oil to be used as a base for making stuff.  I don't know if it's degummed or not, so I don't know if it's suitable for running an engine on.

[Randy Cuberly]

Check with motorcycle shops.  IIRC the lubricants available are castor-based and way expensive, but aren't pure castor.

If you get desperate, modern hippy-dippy cosmetics places sell castor oil to be used as a base for making stuff.  I don't know if it's degummed or not, so I don't know if it's suitable for running an engine on.

Castor oil is available from Sig in Quarts or Gallons.  No hazardous shipping charges. Do not use Castor oil unless it says De-gummed on the label.

You can order fuel from them also but the hazardous fees make it pretty expensive in one gallon lots!

For the Fox you want 26 to 29 % castor oil in the fuel with 10% nitro.

Randy Cuberly

Randy Cuberly

[Paul Walker]

The LE radius looks too small. Probably should take a plane to it and make a larger radius. Too small of a radius will make for poor flying qualities|.

[Perry Rose]

 Replace the pushrod with a carbon tube.

[Scott Richlen]

Looks really good!  And, at 35 ounces, it should fly very nicely for you.  As previously said, make sure you demount the engine and break it  in right using the correct fuel.  A Fox 35 should run for about forever if broken in correctly and fueled properly.  I think you'll be very happy with this plane.  (But not sure I'd pay $1500 for it..... )

[John Park]

The LE radius looks too small. Probably should take a plane to it and make a larger radius. Too small of a radius will make for poor flying qualities|.

The gentleman who built it certainly did a nice job on the finish, but he doesn't seem to be much of a sandpaper enthusiast.  I'd have radiused the top and bottom of the fuselage as well as the LE - but 35-and-a-bit ounces sounds good and light, so the kit wood must have been excellent stuff!

[Mike Griffin]

I hope this helps you

Mike

[Bill Adair]

Chancey,

Sig lists the plans for only $5.75, but you may have fun finding them.  

Listed under Airplanes, Control line, Kits, and then Kit parts! Click on the Twister name to show the plan. Might be easier to do a search on the part number, but I didn't try that. P/N is - SIGKP022

Just tried the search, and it does work.

I don't know who does their web site, but it's a bit confusing to me.  

Bill

[Dennis Saydak]

Guys, Chancey came over for a visit today and I took a look at the Twister. Basically it could be flyable with a little work:
1) The controls are very stiff mainly due to the hole for the bellcrank to flap opening being too small, which is causing some serious binding of the controls. He'll open it up to free up the movement.
2) It is severely nose heavy. I'd remove the muffler and spinner. I'd also replace the prop with a wooden lighter one. Or, tail weight could be added to compensate for the extra long nose moment. The model itself is quite light.
3) The wing has a bad warp. Fortunately it will allow the model to fly in level flight ok, but not inverted.
4) I'll see if I can round up some castor oil or caster based fuel so Chancey can at least get the Twister in the air. Castor is hard to find around here.
5) There is no pushrod keeper at the elevator horn. So that needs to be fixed.

Thanks for everyone's input.

[Brett Buck]

Keep us posted.  Remember that the Fox 35 wants lots of oil, and most of it castor -- see if you can find a "what should I run in my Fox 35" thread someplace.

   And hopefully, the "what should I put in the bypass of my Fox 35 to keep it running through outside corners" thread, too.

     Brett

[Chancey Chorney]

A BIG thank you to all for the help given. It is greatly appreciated. Also a BIG thank you goes out to Dennis for your time and help this afternoon helping me with my problems, and getting my engine to run great.

[Chancey Chorney]

Forgot to add. Thanks a lot Mike for the copy of the original plan. I got it now and just tiled it. It will be good enough to work with in case of.... well, lets not go there for now!

[RknRusty]

Hey Chance
Don't forget to check that Lead edge shape as Paul mentioned. It looks like the builder didn't spend much time shaping it(hard to tell for sure in the photo though). I have a Twister LE shaping gauge that I'll trace and send to you. You can use it to cut one out of plywood so you can get it rounded off to the right radius. It will hunt(roller-coaster) and never find its groove if it's too sharp or squared off. I know you don't want to peel the covering off to do that, but it's a lot better than the frustration of a plane that won't go where you point it. I'll put that tracing in an envelope for you tomorrow.
Rusty

[Dan McEntee]

Guys, Chancey came over for a visit today and I took a look at the Twister. Basically it could be flyable with a little work:
1) The controls are very stiff mainly due to the hole for the bellcrank to flap opening being too small, which is causing some serious binding of the controls. He'll open it up to free up the movement.
2) It is severely nose heavy. I'd remove the muffler and spinner. I'd also replace the prop with a wooden lighter one. Or, tail weight could be added to compensate for the extra long nose moment. The model itself is quite light.
3) The wing has a bad warp. Fortunately it will allow the model to fly in level flight ok, but not inverted.
4) I'll see if I can round up some castor oil or caster based fuel so Chancey can at least get the Twister in the air. Castor is hard to find around here.
5) There is no pushrod keeper at the elevator horn. So that needs to be fixed.

Thanks for everyone's input.

     Not to be argumentative with former NATS and World Champions, but what you have will fly just fine for you once you take care of the laundry list that Dennis spelled out. No sense in rebuilding a nice looking airplane for someone at your skill level. Even the pointed leading edge won't hurt you while you are learning and after a couple hundred flights, and then building one with a nice, rounded leading edge, you may see and feel the difference. I would recommend the brace or fair lead for the push rod. Just use the old cotter pin trick about half way down the rod. I would also add a double layer of brass tubing to the hole where the landing gear plugs in to the fuselage. Landing forces will wallow the hole out after a short while. I use a short piece of 5/32" tubing inside a short piece of 3/16" tubing, and glue it in the hole. That usually lasts the life of the airplane. Break in the engine as recommended already. Mount the tank a bit higher than what it is set at already. As for prop, start out with a 10-4 or 10-5 and speed the engine up a bit. I find that this helps avoid the Fox burp that has been mentioned. I have quite a bit of time with the Fox.35 and I swear that I have never experienced the dreaded Fox burp. I learned early on to set up my planes with the flatter pitch props and I think this is the reason why. Higher RPMs must make for more and better fuel draw I'm guessing. If you do experience flame out on corners, there is plenty of info on the forums for doing the bypass stuff. But at this point in your progression, just get it flying and have some fun without over loading yourself. You can add castor to the Omega fuel that is available to you. It is a half castor mix but only about 18% total oil. Add 6 or 8 ounces to a gallon and you are in the ball park. Any of the nitro content mixes will be OK, but the 5% is cheaper and that is always a consideration, but lots of guys use up to 15% nitro also.
   Good luck and have fun,
   Dan McEntee
   

[john e. holliday]

I agree with Dan.   Get the bird flying while you build one with the improvements.  Also don't be afraid to put this one back together if you do have a mishap.

[Scott Richlen]

consider your first major mishap an opportunity to round that leading edge....

[RknRusty]

consider your first major mishap an opportunity to round that leading edge....

When that time comes, maybe you can start sanding right through the silkspan on the LE, and if you can manage to do it without detaching it completely, you can re-cover just the LE with a long 2" wide strip of some cool looking Monokote trim. I don't know if that's possible, as I haven't worked at all with silkspan on a wing, but maybe it's worth a try. Some experienced silk spanners here might confirm if that's a good idea or not.

I got your Twister LE gauge tracing in an envelope today, and also one for my Florida friend Jim Mynes. He read this thread and wants one too. Good luck with your new toy.
Rusty

[badbill]

Just wondering, always learning something new... How can a wing warp affect upright flight but not inverted? Or vice versa?

[Dennis Saydak]

Just wondering, always learning something new... How can a wing warp affect upright flight but not inverted? Or vice versa?

Each wing panel viewed independently along the trailing edge essentially appears straight. However, when the entire wing trailing edge is viewed from the rear, the inboard wing trailing edge hangs down very noticeably compared to the outboard wing (essentially a "straight" wing warp). In normal level flight the extra air pressure under the inboard wing  makes the model fly tighter on the lines (model wants to roll/fly out of the circle). However when flipped over inverted the reverse happens and line tension is reduced or lost completely (model wants to roll/fly into the circle). In this case the warp is severe enough to lose complete line tension inverted or attempting an outside manoeuver. That's why a wing has to be built as straight as possible. This warp can't be steamed out.

In this case Chancey is "lucky" in that he is at least able to put the model in the air and fly round & round. Had the inboard wing been warped the other way the Twister would likely have lost all line tension on takeoff and flown into the circle. Hope this makes sense.

[Chancey Chorney]

Thank you Rusty!