Perfect Tanks and Wen-MAc Props/Silkspan

Dan,

We may be interested in "Perfect" tanks up to 3/4 oz as long as they are brand new. If you have some please send a list to: support@coxengines.com and we can pay you the same amount we pay our current supplier for those.

I'm not familiar with these props. What are specs?
Hole Dia:
Blade Count:
Blade Dia:
Blade Pitch:

Are these appropriate for regular use? Or only for display? How much per prop? Do they come with spinners?

Thanks,
Jim in MS

Hey Dan,

Have you used the faux silkspan? If so what did you think?

944_Jim wrote:I'm not familiar with these props. What are specs?
Hole Dia:
Blade Count:
Blade Dia:
Blade Pitch:

Are these appropriate for regular use? Or only for display? How much per prop? Do they come with spinners?

Thanks,
Jim in MS

Hi Jim;
These are the same props that were used on most of Wen-Mac plastic ready to fly models. They are three blade with square tips, 4.5 inches in diameter, 3 inch pitch, red in color, and hole size is the same as Cox models and other RTF airplanes, to fit a #5 or so bolt. No spinners/ They are a "flexible" plastic and may be less than 3 inch pitch. They may work OK of a small, really light Cox powered control line model or sport free flight model. They didn't pull the Wen-Mac models very well, hardly at all really. I think a friend of Chris McMillin's managed to get flights on a Wen-Mac Dauntless using a good 6-3 prop and some extra nitro. These are new in package with Wen-Mac part number 800-112. They may not be the best prop but if you are fixing up a Wen-Mac RTF plane and need a prop, these are what you need to keep it original. I think I have about twenty of them and I'll start off at 5 bucks a piece plus postage for them. I think that is cheaper than what you see them for on eVilBay, where you can go to see photos of them. I don't know much about doing the photo thing here.
Thanks a lot,
Dan McEntee

Cribbs74 wrote:Hey Dan,

Have you used the faux silkspan? If so what did you think?

Hi Ron!!;
This isn't "faux" silkspan, in my opinion. it's the real deal. The manufacturers call it a "crepe" type of paper.It has a grain that runs the length of the role, looks and feels just like the K&S stuff to me. I think it's pretty good quality stuff, as you would expect from the medical industry. It is used as a barrier for exam tables, the paper you jump up on and wiggle your bum around on trying to get comfortable. It's strong enough to take that punishment! I haven't covered a model with it yet but I'm working on it. Others on Stunthanger have and report good results. Sparky has posted a video of a guy covering some test sections with it and applying dope, them force drying it with a heat gun. I have taken sections of it and run it under the kitchen faucet to see how it handled wet, and it didn't fall apart like toilet paper or poor quality silkspan would. I could handle it, unfold it it it got folded over on itself, way wetter than you would if you were covering a wing wet. Prices for the stuff by the case are all over the place on the internet. Some guys aren't interested in a whole case, but shipping single rolls is ridiculously expensive. I think there are people that would be interested in it by the sheet like they used to get it at the hobby shop, just to try it out if for no other reason. The paper is 21" wide, and I would cut it off at 36". I think I can fold it up neat enough to get it in a large envelope and mailed in good shape. I was thinking a buck a sheet, and that is cheaper that the old K&S stuff was when it was available. You have my contact info, drop me a line if you want to get a few sheets to try out.
Type at you later,
Dan McEntee

Pm sent

944_Jim wrote:Pm sent

Hi Jim;
Just sent you an email.
Thanks a lot,
Dan

Another PM sent.

Ron

Big Happy Dance!

Got my Docspan today! The paper was packed fabulously...Plastic wrapped and protected by a manila folder within a flat envelope. Dan took great pains to make sure it could survive being tossed up on the porch as if it were a Sunday newspaper!

I immediately pulled my Guillow's Mosquito kit kit out, and compared the old Guillow's paper to the new stuff.
My initial observation is the new stuff has a tighter "weave," but feels like it is the same thickness and flexibility.

I'll try to weigh the two sheets, and compare weights vis-a-vis square area. Expect the numbers in the next day or two.

I wish I had an assembled model for this stuff right now.
Things are about to get busy for me, so I may strip the gift tissue from my Lil Satan just to have a frame to hang this stuff on.

If this stuff works like I expect it will, I may want to find a whole roll.

Thanks Dan!

Good afternoon all,

This is just a simple density comparison  of the "Doctor's Office Exam Table Covering" that may (will!) work in place of silkspan...henceforth colloquially know by me as "Docspan." Docspan is easier to say, and it describes two key features...where it came from, and what is represents to us.

I weighed a sheet of DanMc's paper, and the paper that I can at best only suspect is original Guillow's paper from my (roughly) 1976 Guillow's Mosquito kit. I still plan on weighing my Mid-90's Guillow's B-25 kit paper, since I know it IS original paper.

While I looked carefully at the Mossie paper this time, I noticed it was A LOT thinner than the Docspan. In fact, the Mossie paper had small voids, and was significantly thinner than cheap gift wrapping tissue. It still felt like decent Esaki tissue...soft, and easy to handle. It wasn't crinkly-stiff like cheap gift wrapping paper.

Anyway, the weights were taken on a digital electronic kitchen scale purchased from Walmart a couple of years ago. No claim to calibration is being made.

The new sheet of Docspan weighs 11 grams, yielding 67 in2/gr.
The old paper in the Guillow's kit is 4 grams, yielding 135 in2/gr.

While the "Guillow's" paper is roughly 1/2 the weight, it is so loosely woven that I can see a fully doped frame taking up much more dope to close and fill the paper. I also suspect the paper would be MUCH weaker than the Docspan, even with all the dope.

I still need to weigh the B-25 paper-but that won't happen for at least a month.
I know I'll dedicate my next model as a test mule for Docspan.

More to follow in July!

Thanks Dan!

WAY WAY back when Dad and I were building micro ultra light indoor models some of the techniques and materials were very very critical as well as the eye hand coordination to apply

Jump into real IC or Electric powered flight and one can pick materials that are exponentially easier to work with

While I appreciate the relative weight comparisons and THEY are important

I have been agnostic on the DocSpan because none of us has yet related the differing sources and materials on several OTHER important factors

Obviously Weigh is one
Shrinkage is another
Ease of cutting/shredding/tearing
grain direction
Shrink direction
Wet usability.... IMO the most important for old shaky hands and poor eyes

I got a few yards one time (1960s) of ULTRA sheer Silk... I am talking maybe 2MM silk on Taiwan.. The stuff was lovely in the hand and cherished by all my Indoor free flight buddies...BUT Dammit I used over 2 yards of the stuff to find some way to get just a few sections for my 28" WS rubber plane for the Gillows wings... wet it and it was impossible to use

Eventually stuck it down dry and then misted with sprayer hoping it would shrink OK

Back to the Doc-Poly(span)...
Is this stuff wet shrink or heat shrink?

In my current shop of models:
Brodak Kote (junk IMO)
MoneyKote
EconoKote
Sig Coverall
Century 21 stuff
MicroKote
ChinaKote
Dave Browns SkyLoft
DocuLam
SLC
FasCal
PolySpan
Brodak SilkSpan
SigMFG SilkSpan
Dharma 5MM and 8 MM silk
Wifes sourced various fabrics
Many SqYard of various weights of CF tissue
Many SqYrds of various weight of FG cloth

As an aside cuz I was just there yesterday looking for 2ea DuBro 4/40 ball links...(place on display board--- but empty----grrrr)

If you do not count about 250+/- 20 year old plastic models of cars, airplanes, and boats (at my LSH) my personal hobby barn/shop, Airplane hanger---- has a much more robust stock of items

Hi Fred;
The stuff I have and sent to Jim is made by TIDI. I have two different weights of the material. One they call "Choice" and the other is called "Everyday." They call both of these a "crepe" type of paper, which makes sense. The "Choice" has their part number 916213, I think and the "Everyday" is 98-1004, I have all the details on a thread over at Stunthanger. Another forum member had examples of the original, old K&S GM and SGM silk span. His sheets were 24" by 36", which is what I remember it coming in. He weighed them on an accurate gram scale. I calculated the area of the sheet in square inches, and curt a sheet of the 21" wide material I have to length that equaled the area of the original, and weighed those. They came to within a few grams each of what the original K&S stuff weighed. The "Choice" Docpaper is the equivalent of the heavier, old SGM, and the "Everyday" is the equivalent of the medium weight GM. Bot of these papers have grain that runs lengthwise on the roll. If you hold them up to a light, you can see the difference between the two. I think it is the real deal silk span, and is a good quality paper for several reasons. It is made for the medial industry, which has rigid standards. It's intended for peopl to jump up on and squirm around on and take the punishment that people's rear ends give it. The first thing I did when I got a sample in my hands was run it under the kitchen faucet and got it soaked. It did not fall apart like toilet paper, and was able to get it stuck to itself, then get it unstuck and laid back out again. I gave a roll of each to Sean. If you get near his house, beat him out of a few feet of each to try it. If you look at the rolls. They are supposed to be 125 feet long. The heavier paper, the 916312, is larger in diameter than the other, another clear indication that it is heavier. I'm trying to get a model ready to cover with the light stuff now to try it out, but others on the forums have used it so far with no complaints that I have heard. This isn't intended to say it's superior to anything else, just that is is as good as a lot of use remember silk span being like, and what we prefer to use. If you like it and it's cheap enough, why not use it!
Type at you later,
Dan McEntee

I know this...this stuff sure looks like it'll beat the Christmas tissue I used on my scratch-built Lil Satan!

That stuff tears when wet, gets really brittle when filled, and splinters when it hits a blade of grass. I've fixed that plane four or five times already...paper only, no airframe damage.

I received my paper. Packaged well and it looks like the real deal. Can't wait to try it!!!

Thanks Dan.