Fillet making tools.

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#1

Hi guys,

I’m on the hunt for tools for making and sanding corner fillets/inside radius corners.

I’ve used pvc pipe, welded up stainless balls onto bolts, and cut radiuses out of plywood and polyethylene sheet for tools to make the fillets.

They all work, but all leave a lot to be desired for a smooth pull. Some putties work better than others, but in the end take a lot of sanding.

I’m curious to hear what methods and off the shelf tools there are to pull the same fillet, every time and how other parts of the world folks are doing this task.

Sanding is either knocking off the tits, and pulling another coat to fill in low spots and then moving on to priming and endless sanding with foam boards with a full bull nose… is there a better way?

Thanks,

Zach

#2

For finishing radius’s we have done all of the above and also buy high density foam sanding blocks from a body supply. The stuff is easy to sand or file to any radius you could want. We then use 2" paper with PSA on it and sand away. To apply the filler we use thick urethane sheet folded or bent to make your radius you want. With practice there is not much sanding needed. Practice makes perfect or maybe its just old age.

#3

Pull your fillets, clean up the egdes with flat scraper, PEEL PLY YOUR FILLETS and put it down with a dry 1" brush. Coarse stiff peel ply seems to work best
Of coarse this is for structural fillets.

#4

Thanks for the tips about bending plastic sheet and the auto body supply foam. I’ve been using polystyrene dow board, or divinycell blocks rounded over. The harder black foam blocks would do better.

I haven’t tried peel ply over fillets, will have to give that a shot. Don’t see why it wouldn’t work the ticket for fairing fillets too.

My structural fillets I do wet on wet with epoxy and cabosil, 3/4 diameter the same as my air roller, with 17 ounce cloth draped over them. The ones I’m talking about are the faired out slick ones that end up sanded out to 320 grit and painted on the deck of a boat hull, or shower stall.

Thanks,

Zach

#5

As ghetto as it sounds, we use spoons for making fillets. They are quite cheap and come in a range of sizes and shapes, also being metal they can soak in acetone for cleaning.