"The Hammer Test"

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o1moregil
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"The Hammer Test"

Post by o1moregil »

has anybody Tried hard foam coating products like this one?, I seen a couple like this, but this one looks like ill take some really bad beating, its called poly-armor, but it looks like they don't sell it, looks like poly armor is exclusive for this company that makes these monument signs.
I don't know how heavy these products are, I guess a little experiment wont hurt, If I can get some thing this hard I would be cutting hollowed white foam cores for my Flying Wings.

heres a video of what I'm talking about:
http://www.youtube.com/watch?v=3NnHyyYB ... r_embedded
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David Drowns
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Re: "The Hammer Test"

Post by David Drowns »

I'm impressed. And look! They're out west! We may just have to see if they're willing to do custom work. If this kind of technology could be adapted to combat what a game changer for durability it could be. I guess some follow up would be in order. Thanks for the post Gil.
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gsjames
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Re: "The Hammer Test"

Post by gsjames »

Their website shows them being at a vendor show in Ft Worth in May. However, the dates are somewhat screwed up on the site. I'll write to them and see when the actual show is. Perhaps I can check it out.

I've got a suspicion that the coating is extremely heavy.
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David Drowns
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Re: "The Hammer Test"

Post by David Drowns »

It probably is heavy for what we do but if it can be thinned to a point of lighter yet still durable it could be worth a few test planes to see how it works out.
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o1moregil
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Re: "The Hammer Test"

Post by o1moregil »

I found something very similar, I placed an order this morning for 1 quart of this stuff , $24.95 for the quart and $14.76 ups ground ( :evil: ups ), I will be testing it in a 1.50" scrap block of regular "snowflake Foam" (2lbs white foam), If I like the results on the scrap piece, I will be covering one of my Russian wings with it.


here's what I have in mind.
I will be using 2lb foam for the cores, I will be fixing my dxf airfoil in away that the wire comes in and makes a cut inside the airfoil, making it hollowed.
The white foam cores that I Have weigh at 3.7oz each core that times 2 is 7.4 oz for a full wing(just the foam), If I go to the hollowed method they will be a bit lighter.
I will not be making the spar cuts on the foam like I usually do because I don't think I will be needing fg rods spars with this stuff, that will save me almost 3oz for the 3 1/8 fg rods I always use.
I'm Trying to save all the weight that I can.

some testing is on the way, If it works it works, i'f not.. well so what, nothing got lost but a few bucks and and few hours :D

BTW heres the stuff I found.

http://dinorentosstudios.com/1-Quart-Fo ... ating.html
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David Drowns
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Re: "The Hammer Test"

Post by David Drowns »

If the weight becomes to big of an issue we were talking about doing just the leading edge and see if it's an improvement. I don't have any yet. In fact I don't have the foam experience (coro guy) but this stuff looks promising enough to get me started. I'll be watching for any reports. Thanks Gil.
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Which_way_is_up
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Re: "The Hammer Test"

Post by Which_way_is_up »

I think that just doing the leading edge is a good idea!
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o1moregil
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Re: "The Hammer Test"

Post by o1moregil »

Just the leading edge is a great Idea, hopefully this thing is light unuff for to cover all the foam, maybe a cupple coats on the LE and and light one on the rest of the plane, the company send me the tracking no. already, took'um about 6 hours.
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Re: "The Hammer Test"

Post by o1moregil »

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Re: "The Hammer Test"

Post by gsjames »

Wow Gil, you are using "FlexiSign Pro". That's a pricey piece of software. Of course with your business, I'm sure it pays for it self over and over.

Leave a vertical web, perhaps 2, in your cores when you hollow them out. Or else use a full depth spar. There needs to be something to transfer the shear loads.
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o1moregil
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Re: "The Hammer Test"

Post by o1moregil »

It is pricey :shock: , but it's the best software for what I do, the update is gonna have to wait till the economy gets better .

Gary, your right I may have to do that, I didn't like how my cores turned out, I might just leave the cores with out the hollow(it's all gonna depend on how hard this foam covering gets, its suppose to reach it's hardest point in 5 days) , I did get to reduce a bit off the weight, from 3.7oz to 2.4oz per core.

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Re: "The Hammer Test"

Post by gsjames »

Another method of "coring" is to use the "Swiss Cheese" method. You heat the end of a coffee can, soup can. or whatever size(s) you need with a torch and push it through the wing. We found that on a typical 400-450 sq inch CL Combat plane that you only save about 3/4 - 1 ounce but on our RC wings it will save a bit more. It usually wasn't worth it because of the lost strength. The CL model on the left of the attached photo shows the idea.
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Gary James
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Which_way_is_up
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Re: "The Hammer Test"

Post by Which_way_is_up »

For those of you with screens smaller then 27 inches! :D

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o1moregil
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Re: "The Hammer Test"

Post by o1moregil »

gsjames wrote:Another method of "coring" is to use the "Swiss Cheese" method. You heat the end of a coffee can, soup can. or whatever size(s) you need with a torch and push it through the wing.


I always wondered how those holes where made :shock: , I was thinking you guys used some kind of door nob drill bit, now I know :D.

I found some other stuff that might work: heres a cut and paste from there web site

Unique characteristics of this product are its unusual strength and its ability to be cut, drilled and sanded. Another desirable attribute is its ability to cross-bond, a molecular substructure that literally creates one giant molecule on the surface of the substrate.
(sound heavy, but worth a try also)

website:
http://www.fxsupply.com/materials/foamcoat.html
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Which_way_is_up
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Re: "The Hammer Test"

Post by Which_way_is_up »

o1moregil wrote:. . . . . . . . . ability to cross-bond, a molecular substructure that literally creates one giant molecule. . . . . . . .

that's not a gay thing or something is it ? :lol:
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