Fillets - A tip from Phil Granderson works out

Not too long ago on another CL board that will remain nameless

Phil mention that he was using some new fillet materials and that he really liked it. It's from Tap Plastics and it's called Tap "500" Filler. I got some of the stuff and thought to try it out.

Now, when you mix it, this stuff looks just like Bondo. Goes on about the same too, but that's where the similarities end. There are pros and cons, first the pros.

Pros:
The stuff is pretty easy to work. You can use a chunk of plywood rounded at the tip to shape it. The stuff sands very easily and is easy to shape, even after it has hardened for 24 or 48 hours. About like Windy's AeroPoxy stuff. It doesn't tear or ball up like some stuff and as near as I can tell, darn near anything will stick to it. And more important, it's relatively cheap. I got a quart for $7.25 with hardner. Enough to do about 25 planes if you tend to use a lot. Oh, and it's not very sensitive to exact amount of hardner. Just put it in until you get a nice flesh color

Cons:
Hope you work fast. This stuff hardens right now! You get about 5 minutes working time. I mean it, that's 5 MINUTES! About enough time to do a single fillet if you don't mess around. Luckily, the stuff shapes pretty easy, so you don't have to be all that neat. Takes a bit of time to figure out how much to mix. I've wasted enough to do 3 more planes just getting the hang of how much to mix.

Overall, I'd say it's a winner. Pretty east to work, just about anything will stick to it and it's cheap. Can't say that about everything.

You can get it at http://www.tapplastics.com under the repairs and sculpting header. They also have some other very cool stuff for not too expensive.

Randy, can you offer any comparison on how heavy the stuff is? Some fillers have to be used for very small fillets because they are somewhat too heavy. For instance, the epoxy mixed with microballoons had to be very low on glue and high on dry filler to keep its weight within reason.

My first question, too--weight. The others are always:
Second--durability
Third--sandability
Fourth--paintability

This one sounds OK for the last three, but some stuff that is extremely light will crack over time. And some is difficult to paint. And some you had better form it right, because you will never sand it. And some....

Since Marvin (alias Bigiron) did a test on various engine cleaners that was quite useful, that would be something to do here concerning the various types of material used for fillets and gap repairs. Is there some useful and repeatable amount that you would be willing to mix and waste--(like a two liter Pepsi cap??)--that you could weigh and we could then mix other similar components and weigh, and each submit their results? If we mention sandability, durability, paintability, it will only be relative to the original user since we won't be able to compare all products side by side, but it would be an interesting thread. Maybe someone can start it new with whatever product they are now using. Choose a repeatable amount to weigh which someone else can duplicate with their product, and weigh in grams for greatest accuracy.

I haven't tried this product, but if it is similar to Bondo, if you use less hardener it will set up slower. More hardener and it sets up VERY fast. I have mixed bondo with enough hardener that it smoked and turned the paper I was mixing it on brown.
Read all the instructions and see if it says that if slower set up times are needed you can do things.
Some two part systems will NOT set up at all when you miss the required mixing ratios. Others will not set up when applied over other products. I found the hard way that Polyester Resin (fiber-glas boat application type) will NEVER harden when put on on top of one-to-one ratio slow drying epoxy glue, but will harden on top of five minute type. Be sure you check for compatability. Some filler (two part types) tend to bleed through and discolor lighter colors of top coat paints over time.
Where can you get this "TAP" stuff?
Bigiron

I'm looking at a can of this stuff as I write. It contains "polyester resin, inert fillers and new microscopic spheres", ie microballoons. I've never used bondo, but I have done a fair amount of FG and this is neat stuff. It is described as a light weight industrial filler that bonds to most surfaces including clean metal. It can be used for structural repairs over a filler material called kitty hair. Without having actually weighed it, it seems fairly light and is very easy to work with except as noted, it dries fast. I use a paper towel and a drop of acetone to wipe the edges clean before it sets. It stays put and shapes and sands easily. According to the label it can be painted in 1 1/2 hours. Be aware that it stinks like FG.
The company bent over backwards to be helpful with my order. They also carry pure talc in bulk. I haven't tried it yet, but looks like the cat's meow for dope and talc mix, since that is the purpose it is made for. Randy gave the URL for the web site above, and they take orders on line. They also carry CF and Kevlar and a bunch of other interesting looking stuff for marine/composite apps. They have several stores on the West Coast. Good folks.

Leonard,

My first question, too--weight. The others are always:

Weighs about the same as Epoxolite. Not too bad, not the heaviest I've used. I've used lighter stuff, but it didn't tend to hold up. I don't believe it will crack or dry out.

Second--durability

Stuff seems pretty tough, as far as it goes. Good combination of useability and durability.

Third--sandability

Stuff sands like butter. Ever carve jelutongue? (sort of a very soft pine without knots).

Fourth--paintability

Nearly as I can tell, ANYTHING will stick to it. I did some tests with catalyzed polyurethane, Sig dope, Brodaks dope, enamel (the stuff that TopFlite sells) and some base filler along with some Model Magic. It all sticks and sticks well. No problems I can see. Seems pretty inert.

Like anything, there are pros and cons as I noted. But it's a lot cheaper than Aeropoxy, it's about the same workability and apart from the fast drying time, it pretty agreeable.

A note on the drying time. If you don't get enough hardner in it, it simply doesn't set up. I did several tests and there is a critical ratio. Too much doesn't seem to matter, but you have to get enough in. Even with the absolute minimum amount of hardener, it sets up very fast. As I noted above, about 5 minutes.

>My first question, too--weight. The
>others are always:
>Second--durability
>Third--sandability
>Fourth--paintability

I've never used it, but I can attest to at least the durability and the paintability. Phil's airplanes are holding up just fine with absolutely no sign of the paint lifting off.
I would go even further and say that Phil's painting system of the TAP fillet and the TAP talcum powder fillercoat, Brodak colors, and car clear paint seems to be the best paint system I've seen. The car clear is drastically more fuel proof than Brodak, and is at least equal in appearance. Phil's paint jobs recently have been works of art, and he's done a lot of them.

Phil's planes always were works of art! I can remember one back in the 60'S or early 70'S that had a black metalic that seemed to be flawless!

I personally liked Phil's plane from the late 80s that was hot pink, sky blue with some sort of transparent material on the wings. Very, very long tail moment.

Glad Phil is back in there flying stunt.

Randy tell Phil that he better be right on this fillet stuff. I ordered some and It cost as much to get it shipped as the material itsself cost. If it don't work good, tell him I will stand a short distance upwind of him and spray paint my plane black so as to get him covered with overspray.
Bigiron

Well, I don't see Phil, but perhaps Brett could pass your message along

The stuff works great for me.

>Well, I don't see Phil, but
>perhaps Brett could pass your
>message along

I'll work it into the endless ration of abuse I give him.