anderswallin.net » IOM Building

CNC-turned stainless steel IOM bulb

Administrator — Mon, 03 May 2010 20:06:40 +0000

CNC-turned from stainless steel, this is a 400mm long and 38mm diameter IOM keel bulb. A slot will be milled in the middle for the keel fin. Unlike a lead-bulb this one will require no surface filler/sanding/painting. But the density (compared to water) of stainless steel is 8 at most, while lead bulbs can be close to 11 (depending on the lead-alloy), which means the volume of this bulb is slightly larger.

PIKANTO hull Nr 1

Administrator — Sat, 26 Dec 2009 21:02:05 +0000

We’ve moulded the first PIKANTO hull!

This is a bit of a prototype since it’s some time since Jari or myself moulded a boat, and also because these are brand new moulds and we have never made a boat in one-go like this before: closed mould with the hull, deck, mast/finbox, and ruddertube all attached in one session. We need a bit of routine and practice to get the whole process of “release-agent > gelcoat > resin/fiber > fin/mastobox > close-mould > seal deck-joint” running smoothly. I am sure by hull nr 5 or so we will have learnt the workflow pretty well

Having said that, this first prototype hull came out of the mould pretty good. There are some problems with an uneven gelcoat layer, and a few places in the foredeck where there is trapped air between fiber/gelcoat. We’re considering either cutting away the rounded flanges on the foredeck, or alternatively moulding the deck from many smaller pieces of fiber that would drape around the challenging shapes better. Anyway we are pretty happy that the boat comes out of the mould with deck attached and fin/mastbox + ruddertube in place. I’ve been thinking about a glass-fiber rudder-tube moulding also, and there’s obviously a possibility to add a support under the foredeck for the jib-attachment point, maybe even the mainsheet post tubing also?

This is with a “home-made” gelcoat made out of laminating resin, colloidal silica, and colour-paste. I’m not sure this is optimal and I remember reading on some RC-airplane forum about using 2-pack (polyurethane? or epoxy?) car-paints as gelcoat. Does anyone have links or experience with that?

Polished PIKANTO hull mould

Administrator — Mon, 21 Dec 2009 17:47:00 +0000

The PIKANTO moulds were polished first with “Oskar’s buffing and polishing compund M-50″ and then with “Norpol Rubbing R-10″, both from Terpol (www.terpol.fi) in Turku.

Shine mould, shine!

Administrator — Sat, 19 Dec 2009 18:06:42 +0000

After sanding with 1200-grit and a 10-15um particle-size fine paper it is time for polishing. We have two grades of polishing-compound. These pics show the coarse type which is polished with a spinning soft disk on a power-drill.

After polishing follows release agents: first Frekote and then wax. It’s still possible we will mould a prototype hull this year. Stay tuned.

Pikanto rudder mould

Administrator — Sun, 13 Dec 2009 16:56:28 +0000

Jari cnc-milled rudder moulds for the Pikanto IOM this weekend. The design is similar to the Sails ETC rudder, but slightly larger and with a NACA 0006 airfoil profile, and a slot for a 4mm rudder stock.

240 and 400 grit sanding

Administrator — Sun, 06 Dec 2009 21:10:32 +0000

When not shopping online for lathe-electronics/parts I have been busy sanding the Pikanto moulds. First the last bits of 180-grit today, then all over with 240 grit, and finally started with 400 grit which I will have to continue with next in the next session. The flat bits and large gently curved areas of the hull are easy and quick to work with but as always the devil is in the details. The deck mould has a lot of edges and features that are tricky to sand, and all moulds have a sharp 90-degree edge which is easily damaged when handling the moulds.

The plan is to go 600-800-1200 grit next weekend and do a bit of polishing after that.

Pikanto moulds

Administrator — Sat, 28 Nov 2009 22:43:24 +0000

Our three-piece hull/deck-moulds for the Pikanto IOM (designed by Graham Bantock) are now ready. The next step is to sand the surface smooth and polish the moulds. We hope to mould a prototype hull before the new year.

More Polish Laerke pictures

Administrator — Sun, 08 Nov 2009 09:58:41 +0000

A Polish Laerke

Administrator — Mon, 02 Nov 2009 21:38:36 +0000

Grzegorz from Poland sent me these pictures of his home-built Laerke IOM.

Noux IOM builders in Hungary and Australia

Administrator — Mon, 21 Sep 2009 09:11:56 +0000

Forster Tamas in Hungary has a nice set of pictures of his wooden Noux:
http://www.rcsailing.hu/photos/wooden_noux_building_(builder_forster_tamas)/

Down Under, Bill Hutch is also busy building. He has first made a wooden plug, then a mould, and finally moulded a glassfiber hull.
http://radiosailingshop.com.au/index.php?main_page=page&id=6