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Author Topic: Twister Builds  (Read 3496 times)

Offline Bruce Guertin

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Twister Builds
« on: July 09, 2024, 08:59:52 AM »
As stated elsewhere in this forum I re-acquired a Twister I built 40 years ago.

As I don't plan on flying that one, I'm going to build two more (at a time) identical ones to re-acquaint myself with modelling. I've set up my building space and began construction. I have an Adjust o Jig and prepared one set of ribs already. I borrowed one years ago and just loved it. My problem is while the rib cutting on these kits is dead on, I can't get that symmetry after I cut the holes for the rods. Yes, I have the fixture for the ribs. Are there any tricks I should know, or should I just start pinning parts to the plans the way I always did it?

Because I'm a detail person, Ive weighed all the contents of each kit to try and average the weights between the two. There's a big difference between the two. one fuselage blank is 69 grams and the other 87.
Bruce Guertin

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Offline Paul Smith

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Re: Twister Builds
« Reply #1 on: July 09, 2024, 09:55:48 AM »
Jigs and fixtures that align gauge holes only align holes and not what really needs to be aligned.

I always make fixtures that align the LE and TE, which is the goal of the exercise.

This involves V-blocks for the LE and tapered blocks for the TE.  They are mastered with an aluminum square tube.
The LE blocks are generic and will fit any model with a square-on-edge LE.
The TE blocks are cut on the miter saw for the required TE angle. 
They are hot-melted to the board with the glue just on the edges, not the bottoms.

When I change to a different model I can usually leave the LE blocks in place and just change the TE angle.

Yes, there is a huge difference in weigh between several 1/2" profile bodies.  The heavier body is stronger and will need less reenforcement. 

Paul Smith

Offline Bruce Guertin

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Re: Twister Builds
« Reply #2 on: July 10, 2024, 07:57:10 AM »
Is that board just a shelf from a Lowe's or Home Depot? The concept looks easy enough.
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Offline Motorman

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Re: Twister Builds
« Reply #3 on: July 10, 2024, 10:18:11 AM »
Having a sweet wing jig is nice but, a flat surface and a keen eye is really all you need. Put the two spars and 1/2 the trailing edge on with no glue and see what it looks like. If it's good hit the joints with some thin CA and go from there.

Offline Ken Culbertson

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Re: Twister Builds
« Reply #4 on: July 10, 2024, 03:25:15 PM »
A Twister is a warp looking for a place to happen.  You didn't think the name came from it's flying ability did you?  My advice is to make sure you have a centerline painted on the fuselage as part of your finish and again on each tip rib.  Makes it easy to spot the warps as they come and go.  It is great to build it as straight as a good jig will allow but don't go overboard.  It is also one of the easiest wings to remove warps.

Ken
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Offline Craig Beswick

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Re: Twister Builds
« Reply #5 on: July 10, 2024, 07:08:08 PM »
I thought the name came from the tail, "Twisting", in flight?
Ted comes on here, perhaps he can clarify?
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Offline Paul Smith

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Re: Twister Builds
« Reply #6 on: July 11, 2024, 12:33:54 PM »
Is that board just a shelf from a Lowe's or Home Depot? The concept looks easy enough.

Exactly.

I go to Home Depot and look at the "cull" rack.  The wood is discounted 70%, often due to small cosmetic defects at the corners.  It works well enough unless it's going into a public area of your house.  2x4's, 2x6's, plywood, laminated shelves.  An 8' piece of stock with a bad spot still has plenty of good material for a modeler.
Paul Smith

Offline Paul Smith

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Re: Twister Builds
« Reply #7 on: July 11, 2024, 12:37:51 PM »
My advice is to make sure you have a centerline painted on the fuselage as part of your finish and again on each tip rib.  Makes it easy to spot the warps as they come and go.  It is great to build it as straight as a good jig will allow but don't go overboard.  It is also one of the easiest wings to remove warps.
Ken

When building a profile fuselage I start out by drawing a centerline as true as possible.  Then I drill about four 1/8" holes spaced from the front end to the tail.  Using these I can find the CL at any point in the assembly process.  This is valuable in the all-important final assembly.
Paul Smith


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