Poly-Fiber Superfil

[Dust]

i forget now - why is this stuff bad?

[John Slade]

its twice as heavy as micro

[Wayne Hicks]

Just do a search on Marc Z's site, key words Superfill, PolyFiber, whatever.

[CBarber]

Notwithstanding its drawback, I have and likely will use it due to it being VERY easy to mix in small quantites....such as to fill holes drilled in the wrong place or drilled to secure parts together with cleco's etc.

Yeah, regular micro is not all that difficult to mix, but is still more involved than taking the lid off of two containers and mixing. For very small jobs I tend to overmake micro. Now that I am on finishing tasks I find it useful.

However, I will go back and read Marc's insight.

All the best,

Chris

[Buly]

Originally Posted by CBarber

Notwithstanding its drawback, I have and likely will use it due to it being VERY easy to mix in small quantites....such as to fill holes drilled in the wrong place or drilled to secure parts together with cleco's etc.

Chris

And people think all the lawyers are smart? DON'T DO IT
Use only epoxy based products on your plane, and two part paint.
If it is good for the environment, it is not good for your plane.

[ZG4Me]

Polyester ("Bondo", 'regular' fiberglass resin) has a different shrink rate than epoxy. Am sure it looks good on paper, and would for a few days/weeks/years, but it'll eventually delam.

Small fills, on the other hand... But it ain't worth it for me.

Like Buly sez.

For Dust, it's like putting varnish over lacquer.

Rick

[Marc Zeitlin]

Originally Posted by Buly

And people think all the lawyers are smart? DON'T DO IT
Use only epoxy based products on your plane, and two part paint.

Superfil IS epoxy. It's just premixed with the filler in one part, so it's easier to use. It's heavier and more expensive, too, but it IS epoxy.

Interestingly enough, there's a great deal of controversy over whether current, high quality polyester based fillers (Featherfill NOT included) are acceptable for use over composite layups. The answer is neither obvious nor clear. Certainly, the safe route is to use epoxy based products, but that doesn't mean that you're doomed to fail if you don't.

[Marc Zeitlin]

Originally Posted by Wayne Hicks

Just do a search on Marc Z's site, key words Superfill, PolyFiber, whatever.

I think what you're referring to is the cozybuilders archives, at:

http://www.maddyhome.com/cozysrch/

NOT my web site.

[CBarber]

Thanks Marc for the link. I just searched the site for superfill and found a lot of inconsistant statements and opinion. Some love it, others seem to feel it is "unpure". I did not find a consensis as to it being heavier. Some feel it is cheaper to use than other systems (West included, I think) since it doesn't shrink (another point of contention was what systems "shrienk" and which ones didn't). Superfill not shrinking was thought to be a reason for it to not have to be filled over as much due to an aplication changing once cured. Also, it supposedly sands very well.

So, to me no red flags, just business as usual....some love, some hate, some don't know......some are adimant as to any of the above. To me, just one more option/tool in my chest. It was demonstrated and praised at the EAA composite workshop I attended in Dallas a few years back....said it was lighter and easier to use......but, methinks, corporate sponsorships MAY have had some influance......maybe not, the instructor may just like it.

It is really easy to mix though for small jobs....IMHO

So, Dust, I don't think it is bad, just different....and a different cost equation.

All the best,

Chris

[John Slade]

did not find a consensis as to it being heavier

Chris, Somewhere in my web site you'll find documentation of a weight/volume experiment. I made similare sized lumps of superfil and micro and measured the weights and water displacement of each. The results were conclusive, at least for me. Weight / cubic inch of the superfil was almost double. Of course it doesnt matter much if you're just filling a few minor holes (Why are you drilling holes in the wrong place anyway? )

Note - The micro was mixed very thick with warm MGS. You probably won't get it as light using Ezpox.

[Lynn Erickson]

Originally Posted by John Slade

Chris, Somewhere in my web site you'll find documentation of a weight/volume experiment. I made similare sized lumps of superfil and micro and measured the weights and water displacement of each. The results were conclusive, at least for me. Weight / cubic inch of the superfil was almost double. Of course it doesnt matter much if you're just filling a few minor holes (Why are you drilling holes in the wrong place anyway? )

Note - The micro was mixed very thick with warm MGS. You probably won't get it as light using Ezpox.

superfil uses the west system resin. how do I know ? I was at the factory and saw them mixing it and the drum said west system all over it. it is made with west and micro and some talc. mixed with a high speed turbo mixer which allows a higher micro the resin ratio then you can get by hand mixing which should make it lighter but it is mixed to be use by every new builder and the ratio that they mix to is not as light as you can do if you warm the resin or mix on a hot day. it is designed to fit the need of the average situation and temp. by the kit builder who only fills a few seams. to me it is a pain to mix the right ratio of hardener to resin and the blue color is to tell if it is completly mixed. the blue color makes contouring difficult as the color is distracting to the eye and it is hsrd to see the shape when you are dealing with to many colors on the surface. one advantage is that the density is always the same and that makes sanding more consistant and less hard and soft spots in the filler makes the surface easier to sand true. when hand mixing, hard and soft filler can be avoided by always mixing the filler with the same micro to resin ratio no matter what the tempature and if it is cold, use a heater while mixing and spreading.

[SteveWrightNZ]

Originally Posted by Lynn Erickson

... mixed with a high speed turbo mixer which allows a higher micro the resin ratio then you can get by hand mixing

I have heard this before and I find it surprising, as I once spilled the bubbles in the mixed-epoxy and ended up with much arm-wrestling with what turned out to be a stiff rubbery harder-than-dough type substance. It was way too thick but after some rolling long pieces of it between my warm palms it was barely useable. Heh, it kinda weighed in around, oooo, NOTHING !!

So why do they need a high-shear mixer to do this ?

S

[Dust]

MMMM - well, unless i can learn how to get absolute full coverage in one fell swoop - it may be the way to go.

As it stands on the strake tops, i am gonna oversand what i have and skim coat the entire surface and resand trying not to sand through that coat at any point

[CBarber]

Originally Posted by John Slade

(Why are you drilling holes in the wrong place anyway? )

Yeah, I kinda figured that comment wouldn't go unnoticed.....so it goes. Sure glad this stuff is easy to repair. Acutally, when I was drilling out my holes through the cowling and wing ledge to connect the two with nutplates, one of the holes was over an acces hole to the aileron control, thus providing only a void to secure the nutplate. The holes looked so nice and evenly spaced too. DOH! Velocity does not specify any right way. It is one of those trial and error, figure it out as you go steps, that is neglected in the manual.

I do remember the micro v superfill comments on your site and it was one of the reasons I delayed using it for so long. Again, I am in the final finishing stages (well, compared to how much has been done with "pure" micro), so the bit of Superfill does not bother me. I appreciate the convenyance of the Superfill. The blue color does not bother me and it seems to just highlight the work I was focusing on.

Thanks again guys/girls.

All the best,

Chris

[UFO Builder]

I haven't been able to mix micro lighter than superfil OR aeropoxy lite.

At 3.5 or 4lbs / gallon, that would be about 2.5 parts micro to MGS by volume!

It sets really fast though, and sands like a dream!