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Outdoor Free Flight Forum => Power => Topic started by: flydean1 on April 30, 2019, 10:20:02 PM

Title: 1/2A Maverick
Post by: flydean1 on April 30, 2019, 10:20:02 PM
I'm building a 1/2A Maverick from an ancient Campbell kit (From Lee's Florida period) for One Design.  Wondering about covering.  My favorite is Ultra Cote Light.  I'm also leaning toward tissue over mylar, or Ultracote with diagonal strips.

Looking for recommendations on this, and other Maverick building and trimming tips.

Title: Re: 1/2A Maverick
Post by: danberry on May 01, 2019, 09:33:46 PM
If you're gonna use a TD I'd recommend the Ultracote Lite. Added diagonal strips not necessary.

Put a couple degrees left thrust into it.
On a TD, get a Top Flite 5 1/4 x 3 prop.

Title: Re: 1/2A Maverick
Post by: flydean1 on May 01, 2019, 09:44:41 PM
Got all the above.  Thanks Dan

Title: Re: 1/2A Maverick
Post by: mick66 on May 06, 2019, 01:43:28 AM

Are you running the TD on suction or bladder?

Just saw your question on shutoff ... obviously if on bladder you can use flood off.
Easily done on a KSB including a quick DT.


Title: Re: 1/2A Maverick
Post by: flydean1 on May 06, 2019, 10:53:35 PM
Bladder, every time.  Simple and elegant.

Title: Re: 1/2A Maverick
Post by: Scottl0413 on May 13, 2019, 09:28:20 AM
Dean, I may be to late to the party but I always add polyspan diagonal strips on wings and stabs that are not geodetic construction! Ref. attached pic.!

Title: Re: 1/2A Maverick
Post by: gstew on June 30, 2019, 01:30:14 PM

That is very interesting.

What do you use as the adhesive?

Any special techniques when you apply the strips?

Do you find the grain direction of the Polyspan (if it has one) and orient the strips with the grain lengthwise?

AND why don't you do a symmetrical pattern top and bottom.

I've done a similar thing with recording tape back in the 1990's, but try finding that nowadays!

Greg in Mississippi

P.S. UPDATE... Scott, I just found this in your Shocer thread:

"...The strips are actually Polyspan and they are under the covering. I apply them with dope than shrink them and apply 2 coats of 50/50 dope before applying the ultra coat lite material. I started adding this on all my nostalgia plans and it really helps with the rigidity of the wing. So I said to my self, self why not on everything so I did. Adds rigidity to everything which is a good thing. If you're not covering with plastic you could put it on before or after, I've seen it done both ways!!! Tissue is good also on really light planes such as the rubber jobs you fly. Attached is a pic. of a Ramrod wing with the added Polyspan strips."

So most of my questions answered except the grain direction (if Polyspan has grain) and why not a symmetrical pattern.


Title: Re: 1/2A Maverick
Post by: Scottl0413 on June 30, 2019, 05:21:45 PM
Greg, Polyspan and tissue both have a grain direction! I always align it length wise to the strip. This is to give it's max strength when the wing/stab want to twist during pwr. flights.


Title: Re: 1/2A Maverick
Post by: flydean1 on June 30, 2019, 07:49:20 PM
I've seen strips applied on top of the plastic covering.  Usually nitrate dope is the adhesive.  I think Dohrman Crawford showed it to me first.  The strips might possibly impart more stiffness when attached to the covering rather  than just the ribs, but not sure of that.

I'm using Dyneema (tm) covering with tissue from the main spar forward top and bottom.  Sorta a poor man's D box.

Title: Re: 1/2A Maverick
Post by: duration on July 01, 2019, 07:14:34 AM
Carbon fiber rib caps top and bottom would be way stiffer. If you need to get around the no carbon rule for some events, consider using Kevlar thread instead of CF. I used this back in the 1980s before thin CF cap material was readily available. Now I use the carbon fiber caps from Alex Andriukov (andriukov models.com). These come pre-striped in several widths and lengths.


Title: Re: 1/2A Maverick
Post by: gstew on July 12, 2019, 12:02:20 AM

LOL... I know about tissue grain, but haven't used Polyspan yet, still dumb about it! Does the tear-test work ok to find the grain on Polyspan?


Good idea, the Kevlar thread. I like it!

What adhesive do you use for the CF capstrips and what for the Kevlar thread?

Greg in Mississippi