Author Topic: Sig Twister Begins! (Read 7720 times)

James Holford · « **on:** April 10, 2016, 09:20:29 AM »

After finally getting a suitable work table like of good size together. I figured it was time to get the ball rolling on the Twister..Placing the Akromaster on the backburner.

For table top I cut to fit a hollow core flush door. I prefer solid but this thing is sturdy with no sag and very level. Converted a shelf I was using to hold all my plastic kits as I already have to desks in my model and couldn't fit another. Zip tied a 18" fluorescent light under 3rd shelf and plenty leg room.

Now the Twister. Pinned the bottom 1/4" bottom spar to table..layed out ribs..marked on LE rib location as well on TE. Threw some glued and used old Testors paint bottles to keep square and align top spar slots.

So far so good.... this is only the beginning on a fun journey I hope!

JoeJust · « **Reply #1 on:** April 10, 2016, 10:52:45 AM »

James, I can't help but feel really happy. Somehow you have grasped the idea of not only building well, you also have shown how much fun building can be. Keep it up!
Joe

Motorman · « **Reply #2 on:** April 10, 2016, 11:16:34 AM »

I have a pin cushion exactly like that.

MM

Stew Robinson · « **Reply #3 on:** April 10, 2016, 11:20:49 AM »

My wife does too. I'm going to have to appropriate it.

Gerald Arana · « **Reply #4 on:** April 10, 2016, 11:24:13 AM »

Quote from: James Holford on April 10, 2016, 09:20:29 AM

After finally getting a suitable work table like of good size together. I figured it was time to get the ball rolling on the Twister..Placing the Akromaster on the backburner.

For table top I cut to fit a hollow core flush door. I prefer solid but this thing is sturdy with no sag and very level. Converted a shelf I was using to hold all my plastic kits as I already have to desks in my model and couldn't fit another. Zip tied a 18" fluorescent light under 3rd shelf and plenty leg room.

Now the Twister. Pinned the bottom 1/4" bottom spar to table..layed out ribs..marked on LE rib location as well on TE. Threw some glued and used old Testors paint bottles to keep square and align top spar slots.

So far so good.... this is only the beginning on a fun journey I hope!

Holy Mackerel James! I thought I had quite a few kits but you've sure got me beat!

Interesting method of holding the ribs until you can get them glued.

Jerry

Gerald Arana · « **Reply #5 on:** April 10, 2016, 11:25:22 AM »

Quote from: Motorman on April 10, 2016, 11:16:34 AM

I have a pin cushion exactly like that.

MM

Me (us) too! Must be lots of them out there...........

Jerry

Mike Scholtes · « **Reply #6 on:** April 10, 2016, 11:40:08 AM »

But I'm worried about the hammer, spirit level, and tiny crescent wrench on the table. Not your typical modeling tools.

My wife too has the same pin cushion - must be a "wifey" thing.

Mark Mc · « **Reply #7 on:** April 10, 2016, 12:22:31 PM »

Quote from: Mike Scholtes on April 10, 2016, 11:40:08 AM

But I'm worried about the hammer, spirit level, and tiny crescent wrench on the table. Not your typical modeling tools.

Maybe not your typical modelling tools....

James Holford · « **Reply #8 on:** April 10, 2016, 12:23:22 PM »

Quote from: Mike Scholtes on April 10, 2016, 11:40:08 AM

But I'm worried about the hammer, spirit level, and tiny crescent wrench on the table. Not your typical modeling tools.

My wife too has the same pin cushion - must be a "wifey" thing.

Lol they were just placed there lol

James Holford · « **Reply #9 on:** April 10, 2016, 12:24:14 PM »

Quote from: Gerald Arana on April 10, 2016, 11:24:13 AM

Holy Mackerel James! I thought I had quite a few kits but you've sure got me beat!

Interesting method of holding the ribs until you can get them glued.

Jerry

Have roughly 200+ kits topic mainly being WW1. Over 100 in 1/72 scale alone

RknRusty · « **Reply #10 on:** April 10, 2016, 12:44:11 PM »

Enjoy the build, James. If you keep us updated with pictures and show us your methods, I'll read it all. I'm finishing up a Fancherized Umland Twister right now.
Rusty

Randy Cuberly · « **Reply #11 on:** April 10, 2016, 12:49:55 PM »

Quote from: Motorman on April 10, 2016, 11:16:34 AM

I have a pin cushion exactly like that.

MM

Yeah as do I...in fact I have two...one appropriated from my wife...Shhhh...don't tell her!

Randy Cuberly

Randy Cuberly · « **Reply #12 on:** April 10, 2016, 01:08:15 PM »

HHHmmmmmm...unusual wing jig. I suppose it's serviceable but watch for warps in the trailing edge! It is very nostalgic...I haven't seen that many little Testors Plastic paint bottles in one place in many years!

Randy Cuberly

James Holford · « **Reply #13 on:** April 10, 2016, 01:19:57 PM »

Yea one of the. There magnet boards would have been nice but this should do ok as long as I don't rush myself that I'm known for doin.

Wondering if I should glue LE first... or assemble TE.first

Dane Martin · « **Reply #14 on:** April 10, 2016, 01:26:02 PM »

Bad @$$ jig James! Lol. Looks like it's working pretty nice.
I'm in the process of repairing my Twister. Looks like it's a twister kinda time!

Ps... I too have that pin cushion. I took it from my mom. I think she thought she misplaced it and got herself another.....

Randy Cuberly · « **Reply #15 on:** April 10, 2016, 02:02:09 PM »

Quote from: James Holford on April 10, 2016, 01:19:57 PM

Yea one of the. There magnet boards would have been nice but this should do ok as long as I don't rush myself that I'm known for doin.

Wondering if I should glue LE first... or assemble TE.first

James I would put both spars in (not glued) then block up the trailing edge with a balsa (maybe 1/4" or even 3/8" square then weight the ribs down to that then glue on the trailing edges. Since it's a non-tapered wing that will probably work very well!

In the future you might consider getting a wing jig like the Tom Morris unit or an Ajusto-Jig if you can find one...maybe on E-Bay!

Randy Cuberly

Steve Helmick · « **Reply #16 on:** April 10, 2016, 02:10:49 PM »

With these kits (SIG, etc), it's a real good idea to stack the ribs and visually match them up. They'll be real close to identical...but not symmetrical top/bottom. So you'd want to flip some over and see if they match better. When you get them stacked properly, put a Sharpy mark in the bottom of the spar notches. If the spars or LE don't align well, you'll get warps...bad deal.

Steve

Mike Scholtes · « **Reply #17 on:** April 10, 2016, 03:34:17 PM »

Here's what I use. Maybe that explains the lack of front-row placings.

Fredvon4 · « **Reply #18 on:** April 10, 2016, 03:45:29 PM »

Steve has it correct even with very good lazer kits I find each rib set has a decernable top and bottom

getting them all in the same orientation save a LOT of grief later

I am now using magnets...but have built a few wings this exact same way with the Testor's bottles

James Holford · « **Reply #19 on:** April 10, 2016, 03:54:57 PM »

Quote from: Mike Scholtes on April 10, 2016, 03:34:17 PM

Here's what I use. Maybe that explains the lack of front-row placings.

Haha

James Holford · « **Reply #20 on:** April 10, 2016, 05:43:26 PM »

Ribs all dried and good. Taped LE in place. Made sure was square and glued. Working on TE as we speak. goin slow with it.

ringmaster · « **Reply #21 on:** April 12, 2016, 06:05:09 AM »

Hello, My friend it is sure very nice to see you building a Sig Twister. I like the idea of using Tester paint bottles to keep the ribs straight on your plan very smart I think. The Sig Twister and Sig Banshee have given me over 45 years of pleasure of flying control line. These two planes are all I needed to fly control line all those years and I plan to fly rest of my life. I think you made very good choice on choosing the Sig Twister she is a very good flyer and I think you will enjoy it and learn to love that plane. Thanks ringmaster and have a great day my friend.

ringmaster · « **Reply #22 on:** April 12, 2016, 07:10:22 AM »

Hello my friend, You will want to keep all your wing ribs cut outs and plywood parts as templates in the original Sig Twister box so when you need to build another Sig Twister you will have them and plans too. I can guarantee you will crash and you will have to rebuild a few times in your life I have been doing that over 45 years of flying control line flying. I still enjoy my planes and building them too. Thanks ringmaster

Avaiojet · « **Reply #23 on:** April 12, 2016, 07:23:07 AM »

James,

Super build!

I can relate to it.

Hey! Do you have a Fokker tri-plane in that kit lot?

Large enough for a 29 to a 35?

Keep up the great build!

Charles

James Holford · « **Reply #24 on:** April 12, 2016, 06:30:56 PM »

Quote from: Avaiojet on April 12, 2016, 07:23:07 AM

James,

Super build!

I can relate to it.

Hey! Do you have a Fokker tri-plane in that kit lot?

Large enough for a 29 to a 35?

Keep up the great build!

Charles

Actually I have about 15 Fokker Dr.1's... Sadly they are all plastic kits lol.

RknRusty · « **Reply #25 on:** April 12, 2016, 09:27:28 PM »

Quote from: Fredvon4 on April 10, 2016, 03:45:29 PM

Steve has it correct even with very good lazer kits I find each rib set has a decernable top and bottom...

I did not know that. Luckily, mine seems to have tuned out fine anyway. It's not a Sig kit, and Walter put a lot of effort into accurate cutting, so maybe they were all symmetrical.
Learn something every day.
Rusty

James Holford · « **Reply #26 on:** April 14, 2016, 06:18:15 PM »

Progress!!!

Still lots to do...install floating bellcrank...run leadouts... sheet center section.. etc.. But slowly getting there!

RknRusty · « **Reply #27 on:** April 14, 2016, 07:49:21 PM »

Nice. You got that done pretty quick. A cleanly built wing skeleton is a thing of beauty.

James Holford · « **Reply #28 on:** April 14, 2016, 09:08:55 PM »

Quote from: RknRusty on April 14, 2016, 07:49:21 PM

Nice. You got that done pretty quick. A cleanly built wing skeleton is a thing of beauty.

lol oh I assure you it isnt perfect..but isnt too bad... it will fly!! lmao

MikeyPratt · « **Reply #29 on:** April 15, 2016, 08:05:57 AM »

Quote from: James Holford on April 14, 2016, 09:08:55 PM

lol oh I assure you it isnt perfect..but isnt too bad... it will fly!! lmao

Hi James,
The wing looks great. As a suggestion, I would add 3/32" balsa vertical webbing between the between the spars, and 1/32" salsa vertical webbing between the trailing edge sheeting. This will keep the wing straighter and stiffer after covering. Keep up the good work.

Later,
Mikey?

Perry Rose · « **Reply #30 on:** April 15, 2016, 09:10:48 AM »

And when you put the leadout slider in move it through it's full travel and remove any balsa that touches the leadout wires. Especially the front wire.

Sean McEntee · « **Reply #31 on:** April 15, 2016, 02:26:29 PM »

Quote from: MikeyPratt on April 15, 2016, 08:05:57 AM

Hi James,
...and 1/32" salsa vertical webbing between the trailing edge sheeting.

Later,
Mikey?

Sounds delicious!

Tim Wescott · « **Reply #32 on:** April 15, 2016, 02:35:33 PM »

Quote from: Perry Rose on April 15, 2016, 09:10:48 AM

"Location: Moosup, CT 06354"

Shouldn't that be "Somewhere down south"?

James Holford · « **Reply #33 on:** April 15, 2016, 05:49:26 PM »

Quote from: MikeyPratt on April 15, 2016, 08:05:57 AM

Hi James,
The wing looks great. As a suggestion, I would add 3/32" balsa vertical webbing between the between the spars, and 1/32" salsa vertical webbing between the trailing edge sheeting. This will keep the wing straighter and stiffer after covering. Keep up the good work.

Later,
Mikey?

Is there an illustration showing what your describing?

Sean McEntee · « **Reply #34 on:** April 15, 2016, 06:23:35 PM »

Quote from: James Holford on April 15, 2016, 05:49:26 PM

Is there an illustration showing what your describing?

Here's a sketch of what Mikey is talking about

James Holford · « **Reply #35 on:** April 15, 2016, 06:26:41 PM »

Ohhhhhh I think I understand

James Holford · « **Reply #36 on:** April 15, 2016, 07:00:06 PM »

Quote from: Sean McEntee on April 15, 2016, 06:23:35 PM

Here's a sketch of what Mikey is talking about

So run it vertical from top of spar right on side of rib down to bottom spar?

RknRusty · « **Reply #37 on:** April 15, 2016, 08:05:38 PM »

James, take a look at this. This is an incredibly good site for those of us learning to build better planes.
http://www.airfieldmodels.com/information_source/math_and_science_of_model_aircraft/rc_aircraft_design/shear_webs_in_model_aircraft_wings.htm

here's the index to many more topics:
http://www.airfieldmodels.com/information_source/how_to_articles_for_model_builders/index.htm

Hope this helps. It's my go-to site when I need help figuring out how to do anything on an airframe.

Quote from: James Holford on April 15, 2016, 07:00:06 PM

So run it vertical from top of spar right on side of rib down to bottom spar?

Yes, you ideally mount them in between the spar, but at our stage of building and flying(not expert and still crash sometimes), it's easier to face mount them on the outsides of the spars(as in Sean's illustration). Not only is it easier, but less stuff breaks in a crash and the webs just pop off.
Rusty

Dane Martin · « **Reply #38 on:** April 15, 2016, 10:09:37 PM »

Here's a shot of on the spars, and the TE webs. These are from my RM 800+p. Same principle. This would be what Sean's drawing looks like.
Makes the wing bullet proof!... Better watch what i say, someone might test that!

And yes, i know the shear web grain is the wrong direction... Lol

RknRusty · « **Reply #39 on:** April 15, 2016, 11:53:53 PM »

Thicker wood makes the wrong grain direction acceptable, just a little weight penalty. My kit even came with it cut horizontally, but 1/16th instead of 1/32nd. Nice neat job there.

James Holford · « **Reply #40 on:** April 16, 2016, 03:31:47 AM »

Sweet!!!! Just might do it

MikeyPratt · « **Reply #41 on:** April 16, 2016, 08:43:28 AM »

Quote from: James Holford on April 15, 2016, 06:26:41 PM

Ohhhhhh I think I understand

Hi James,
Now that you understand it, make sure you block up the wing so that it is perfectly straight before you add the webbing (spars and trailing edges). Some people will say you to sheet the leading edge from the spars to the leading edge. That is fine, but not necessarily for this model. Save that for your next Twister because you will more than likely damage it some time learning to fly stunt and repairs will much easier to do.

Good luck and keep us posted,

Mike Pratt (aka Mikey)

RknRusty · « **Reply #42 on:** April 16, 2016, 11:19:32 AM »

Mikey's right. I believe webbing in the first four bays from center is usually adequate.

This is the time to check the wing for minor twist, because if there is any, you might lock it in place with the webs. To check for twist, get a couple of CF tubes or arrow shafts, I've even used yard sticks on edge. Lay them so they sit resting on the spar and TE as close to the tips as possible(make sure your reference sticks are not laying in a dent or a dip in the TE or spar). Back off 15' and crouch and eyeball the two sticks and see if the farther one disappears behind the closer one. If there is any twist in the wing, the sticks will be criss-crossed, so it will be apparent. Careful work with ammonia glass cleaner, heat and force can be used to straighten it. You probably will have to counter twist it slightly to get it straight when released after it dries. A hot hair dryer helps, but not a heat gun.

This is just my method, others may disagree, so proceed thoughtfully.
Rusty

P.S. I realized after writing that, Mike said block it up straight... same thing I'm getting at, but this will help it be straight when you do block it in place.

James Holford · « **Reply #43 on:** April 16, 2016, 01:23:42 PM »

Cool advice. Just looking down the LE it's pretty straight.. but not aligning the LE perfrctly square it's very ever so slightly swept wing but very very minimal.