Fairing filler......

[Roly]

There is always the easy way to do things, and I gotta get this right as it could turn into a major time consumer.
To those who know..........been there done that.......have the "force"


Microspheres + aerosil---411
Microballoons + aerosil---407
Microlite + aerosil---410

I have studied the west systems site but if you seal the faired finish with neat epoxy there seem to be little advantage except price. 410 is not recommended under dark colours, hard chines or thick as it is soft.

How is the trowelability of 411 relative to 407?
I am keen to get a good finish.

[SailDesign]

For real fairing, don't use any of the above - use Awl-Fair from AwlGrip. Goes on smooth, sands well, you name it.
http://www.marineware.com/awlgrip_4.asp
Steve

[bobsyachts]

when fairing use Awlgrip or international much better for sanding or even Hempel which is a little cheaper.

[Roly]

Thanks for your comments--Awlfair is not available here so it is a "mix my own
scenario". Also, I can save money for elsewhere!
Just can't see the advantage of using 407 phenolic MB's, as they are 4 times the $'s. Guess I will stick with 411(MicroSpheres) + 10% aerosil.

[yokebutt]

Roly,

For fairing I really like using Q-cell (very easy sanding, and the glass balloons are nor suceptible to heat) and as little fumed silica as I can get away with without sagging.

Yoke.

[Roly]

Thanks Yoke. I actually thought microsheres (411) was actually part Q-cell and colloidal silica?

An epoxy adhesive can be blended from a suitable epoxy resin thickened to a non-sag consistency using a low density modifier such as Micro Spheres, Glass Bubbles, Q cells or Phenolic Micro Balloons.

This was from the Baltek site.
What is the difference between M.S's, glass bubbles and Q cell??

[lprimina]

Steve is right use Awl fair, you can get it shipped to you.. The money you save with cheaper means is wasted on time and energy plus the easier sanding means less mistakes. I cant say anything about Q-Cell I havent used it.
Ben

[JR-Shine]

For pre made epoxy fairing - Quickfair by System Three

For "mix your own" - 4 parts Microballoons (phenolic) to 1 part silica by weight.

The Quick Fair is better and you can sand it with a machine in 4 hours - that alone makes mixing your own no longer worth while.

Joel
boatbuildercentral.com

[yokebutt]

Not too crazy about phenolic balloons, harder to sand and also more difficult to hide due to the dark color.

Fumed silica has the curious quality of making putties thixotropic and much easier to shape accurately, but it improves the abrasion resistance a lot too.

Yoke.