Thursday, December 09, 2010

Lots of small steps on the way to the paint shop

I'm struggeling on, using small envelopes of available time between other obligations, to make the floats, rudder and case, main hatch and bow pole ready for delivery to the paint shop, and the workshop available for mast building.  Some pictures from the process:

 Fairing the wing net rails


 Aft view, two year old epoxy coat sanded to 180 grit

Primed.  Next, I will sand the whole surface to 240 grit and apply a last layer of primer before transportation.

 Fairing compound added to the other side of the rudder blade

 Sanded, 120 grit

Hibuild primer applied

Gudgeon cut outs made with the strapped down router

Laminating cut outs

 Laminating last layer on tiller stub

 Foam dug out to accept tiller

Hole for the rudder pivot pin

Main hattch was very uneven, this is how it turned out trying to fill the lows.  The hatch is also the prime test site for different mixing ratios of my micro, to be used on the main hull.  Light, easily sandable when mixed correctly, and cheap compaired to finished compound.

Faired down, ready for the big fill

 The hibuild on the bow pole was sanded to 180 grit, and a few imperfections filled.

Coated with another layer of hibuild primer.  This is also to serve as a transport surface when delivering the parts to the paint shop.  It will there be sanded and one layer of Speed Undercoat and two layers of TopGloss will be sprayed. I will not reveal the colour, but I'd be surprised if the designer disappoves..


Anonymous said...

Hi Tor , great progress , are your fingers worn back to stubs yet ? Those wing net rail supports were a big consumer of time and fingers . When you mix your own fairing compound be very careful to keep your mix ratio constant or you will get areas of different density and consequent problems with the softer areas abrading more easily and giving low spots . We used the SP quick-fair , bit more expensive and maybe a fraction heavier but constant density and if your layup is fair ( and it looks good ) very little ends up on the boat anyway . Keep at it . Cheers , Jim Buckland .

Andrew said...

Interestingly, I found that QFair continues to harden as it cures over several days (not a surprise as other epoxies do this also). So, if you have a hard cured base, thin fill some low area, then sand as soon as able ('soft' by comparison) -- the two surfaces will sand differently. Whether you're happy with the results may depend on equipment, technique, size of the fill (area, not depth), etc. . . . many variables to the process it seems.

Note: SystemThree SP now has 'Slow'Fair. Longer till sand-able, but longer working window. No experience yet, but I think I'll give it a try at some point.


Tor Rabe said...

Thanks! Jim, I know, but I had the same problems using SP S fill 600 I think is the name, on the floats. I believe the thing is to follow the steps lined out in chapter 25, link on "filling lows" and "big fill". What I found was the main drawback with the SP system was the time required until sanding, several days in my workshop, artificially heated to 20 deg C. Dayly temps higher than that is very unhealthy for my wallet and the environment. Anyway, I found that 30% micro (by weight) makes a very easily sanded compound (far easier than the SP), but hard to apply as it tends to roll off the surface unless applied very slowly with a lot of force. 27% might be a good compromize. A 20% mix is ideal for the last scimming coat, filling pinholes and grit 36 scratches. I'm using my fast hardener (Svapox epoxy system) which makes it necessary to mix smaller batches, like 200 - 300 g at a time, but then I can start sanding the next day.

Anonymous said...

Yes , even here in Winter the SP system is an overnight cure before being sandable . When it is a problem we throw a sheet of bubble wrap over the item needing cure and heat that - way cheaper and more efficient and works even on our coldest days - not that they can compare with yours ! Cheers , Jim B.