Wednesday, September 29, 2010

Mast Construction


Still going with the mast, all the 'thin' stuff is done (thin spars and spacing blocks are all glued up). I used clamps, panel pins and sticky tape to get everything to stay in place. Plus some tactical placement of concrete blocks and bits of offcut.

Fat bits tomorrow night.

Monday, September 27, 2010

Shaped the Narrow Mast Faces

I marked out and shaped the narrow mast spars tonight. I was going to use the router to shape it but by the time I'd 'jigged' it up with guides and clamps it would have been a week next Tuesday.

In the end I just marked it out with pencil, clamped both narrow faces together and power-planed them both together. Seems to have worked out pretty well. Very hard working with timber over 5m in length.

The timber is finger jointed pine of some type (radiata, I guess). Cheap and relatively nasty, so it will be interesting to see how it stands up to serious use. Hope I'm not wasting my time.

Centreboard a Tight Fit

I tried out the centreboard in the centreboard box yesterday (sensible place to try it out) and it didn't fit... very well. It was VERY tight.

Even though there should be plenty (well, a couple of mm's) space I think I know what went wrong. I used a large concrete block to 'clamp' the centreboard box together when I was gluing it. I remember that the brick didn't go all the way across, meaning that it left a slight bow in one side of the box. So, the 2-3 mm's of free space has disappeared and it is now too tight. I should have had a 25mm spacer in the centreboard box to keep it at the correct width.

I'll jam a thick spacer in there for a couple of days and see if it takes the curve out of it and gives me the correct fit. Fingers crossed.

Saturday, September 25, 2010

Alternate to Bote Cote

I'm going to run a little bit short of Bote Cote and even though it's great stuff, I don't think I'll make a special trip out to buy a new bottle, or get it posted to me.

There's only the mast glassing to do (I think), so I might cheat, go to Bunnings, and just buy a big tube of Araldite and use that to glass the mast. I'll see how much it costs first.

Second Foil Glassed

Second foil glassing was much more successful than the first. Always easier the second time. For a start I didn't drop it and crack off part of the edge (which has repaired fine).

Takes about 10 squirts of epoxy (plus 5 of hardener, of course) to cover it.

Now I just need to give it its second coat of epoxy, then rub back and give it a few coats of varnish to finish it. After seeing how easy it is to chip and damage the thin back edge, I'd always glass these things, not just epoxy them.

Updated Pickies

Glassed First Foil

The first foil is glassed and that didn't go real smooth either. The points to note were:
  • It takes about 12 'squirts' of epoxy to coat the glass on the large foil. 10 squirts do the small foil.
  • I coated both sides of the timber with epoxy, then wrapped it in glass. The epoxy held it in place while I put on a second coat. To keep the edges from unwrapping I used spring clamps to hold the edges together (see photo next entry). You could also use clothes pegs.
  • The foil was 'mounted' for glassing by putting long plaster board screws in each end and propping it between two saw horses. This wasn't really secure and the large foil dropped onto the floor. Took me ages to pick out the dirt and sawdust in the sticky epoxy.
  • When it dropped it snapped off a small piece of the thin trailing edge. Hopefully I've managed to repair this during the glass coating.
  • Used the glad wrap trick again to help hold the fiber glass in place. This worked well to hold the thin trailing edges in place (this is where the wrapped fiber glass met). It also seems to have worked well holding the tighter curves in place.
The 1.5 litre Bote Cote epoxy kit isn't going to be enough. I'll have to buy another one... another $65.00.

Paint Not Good

So many things wrong with the paint job:
  • Runs from putting it on too thick the first time.
  • Runs still soft, with a skin over wet paint, even after five days drying.
  • When I put on the next coat, it blistered where the runs were, despite lots of rubbing back (thought I'd got rid of all the soft paint, obviously hadn't).
  • Put the last coat on with a foam roller, and there were thousands of little bubbles that left tiny 'pin holes' in the paint.
  • Tried a lambs wool covered roller... left lambs wool in the paint!
All in all, not real happy. I'm not wasting anymore time trying to get a better finish. Time to move on.

Don't think I'd use Kill Rust again, just a good quality exterior latex acrylic house paint, probably semi-gloss.

Tuesday, September 21, 2010

Paint Technique Not So Successful

When I was painting the hull I noticed that if I went over the first light coat of Killrust (which was applied over two undercoats) after about five minutes the second coat covered very well, though it did appear to be a little thick. This was confirmed 24 hours later as it showed bad runs.

After three days the thicker paint, though skinned, wasn't actually dry under the skin. I've rubbed the whole hull down with sandpaper, which removed the skin and exposed the wet paint underneath. I'll wait a couple of days for this to dry and hopefully be able to re-coat.

From now on it's one thin coat, light sand, second coat. Just like the instructions say!

Monday, September 20, 2010

Finished the Rudder Box

The rudder box and tiller are a complete unit now, with gudgeons attached. I'll have to do a bit of paint touch up here and there but all in all, I'm very happy with the result. Looks quite professional (from a distance ;-) )

Tips for Making and Glassing the Foils

Mike Storer describes a process of using a normal plane, torture board and sandpaper to shape the foils. A torture board is a long piece of flat board with sandpaper clamped across the face and held in place at each end with blocks and screws. This gives a very traditional way of shaping the foils.

I like power tools. I got both of my foils done in about an hour each using an electric planer and an orbital sander. If they're not perfect then that's my inexperience, not because I didn't do it with hand tools. If anything I think it was easier with the power tools. The most I took off at a time was 1mm with the planer and most of the time it was half that. I.E., don't be in a hurry.

As for the fiberglass coating of the foils, I tried a trick Dave Carnell uses to butt-join sheets of plywood using fiberglass. He provides a lot of detail here but from that I took away the fact that cling wrap doesn't stick to epoxy fiberglass as it's setting. So, doing the tips of the foils, even when using double biased glass sheet, you still get little bits of the cut fiberglass sheet poking out into space. Nothing makes these bits behave, doesn't matter how often you revisit them and poke them down into the setting epoxy. They always eventually stick out. So, I wrapped cling wrap over the tip of the foil where the curves were tightest and ended up with a great result; not 'sticky-out' bits. The wrap just peeled off once the epoxy had set. There were some 'crease' marks from folds in the wrap but if I'd been a bit more careful those wouldn't be there. As it is I'm pretty sure a quick sand will fix it up nicely.

Finally, a trick I learned from the Woodworking Forums (at least, I think that's where I saw it) when working with 7008 two pack wood finish works pretty well with epoxy too. To keep mixed 7008 from 'going off' when you have some left over, you simply cover it and stick it in the freezer. I was ploughing through paint brushes, losing one every time I put a coat of epoxy on the woodwork or did any fiber glassing. So again, I wrapped my last brush in cling wrap and popped it in the freezer. When it first came out it was as hard as a rock but after a little while it softened up enough to do my next epoxy application. I've wrapped it back up and will see tonight if I get to use it again.

Saturday, September 18, 2010

Hull Gets First Coat and Foils Cut and Shaped




Good day today, got lots done.

Actually, it was more a case of the foils not taking as long as I thought. Just used the power planer and orbital sander and before you knew it, two beautiful looking foils. For racing, Mike Storer (the designer) recommends they be glassed, then painted white and rubbed back with wet-and-dry paper until they are uniformly matte. This makes them very quick through the water.

Would you do that to two gorgeous bits of wood like that? Not me, they're getting a glassing and varnishing. Who'd want to lose that look?

I've also added kwilla (left over hardwood from the deck that I built) to the leading and trailing edges of the foils to add a bit of protection to the western red cedar.

Friday, September 17, 2010

Marked out Tiller and Daggerboard

Marked out the tiller and daggerboard today and have cut the templates ready to start shaping.

The plans recommend turning your jigsaw upside down and mounting it in a vice, using it like a tiny band saw to cut out the templates. I tried it and it actually worked really well.

Have to remember that little trick, though you do have to watch your fingers!

Bondall is Better

The Bondall marine varnish was a total success, worked much better than the Wattyl stuff. Was actually a couple of bucks cheaper, too. Finish looks great.

Too Much Work

Wow, the 'glassing' and finishing takes ages. I really think I might skip this step next time, sticking to the PDR concept of getting something quick and cheap.

The $65 worth of epoxy is more than half gone and I've still got the foils to glass. Hope I have enough left. I haven't used anywhere near as much epoxy as recommended in the plans (used Selley's Platinum for gluing everything together, didn't encase the boat in epoxy, haven't used epoxy to fillet any of the joints). Basically I've only used it to coat the tiller and tiller extension and glass the hull joints.

I've also done just enough plain epoxy to cover the fiberglass, then leveled out the rebate with epoxy and high strength filler. In hindsight, I should have mixed this a little thinner than 'peanut paste' consistency so that it flowed and smoothed out a bit more than it did. Not enough to run, just enough to level. As it is I ended up with a fairly rough finish due to the thickness of the 'epoxy bog' so ended up smoothing everything with builders bog. This set faster, was easier to sand smooth and was cheaper. I know it's a little soft but it will have a lot of paint over the top of it so should be adequate. I hope...

Also, should have scraped all those runs off when the epoxy was still soft. The sander just doesn't get through it once it's set, that Bote-Cote is tuff-stuff. The plans tell you to do that but I put the last coat on fairly late and then just crawled into bed. Regretted not scraping it all back today.

Thursday, September 16, 2010

Edge Glassing & Rudder Box




Today I planed about 1mm off all the edges of the hull and 'glassed' 50mm tape into the resulting rebate. This seals and toughens the hull at the most likely point of failure. Important when I'm doing the Brisbane to Gladstone race. That, plus the other small bits of epoxying I've done has used up about 800mls of the 1.5lt Bote-Cote kit. Hopefully there will be enough left to glass the foils.

Of course, this is all being done in line with the OZ Racer design concepts. When M saw me doing this he wondered why I was bothering. To be honest, if I was to stick to the pure PDR concept, I'd have knocked this thing up in a day and given it a coat of exterior house paint. Might try that one day, just to see what the differences are.

Also put the first coat of paint on the rudder box. This will give you an idea what colour the boat is going to be.

I've changed varnishes too. Moved from the disappointing Wattyl Exterior to Bondall Marine Grade so let's hope the tiller arm doesn't crocodile this time.

Wednesday, September 15, 2010

3D



Okay, it's official, I've gone 3D.

Also stripped and recoated the tiller arm. Let's hope the varnish behaves itself next time.

Rowlock Positioning


The Wader's web page (see sidebar for link) gives a couple of sites that help with locating the best spot for rowlocks. They also give a summary of the best spot for a PDR. This is where mine are going to end up.

New Hint Re Glue and Eyebrows

The Selley's Platinum glue is magnificent stuff however, don't get it in your eyebrows or mustache. You will have to lose both to get the glue out.

Considering this sticky stuff gets everywhere, just be careful.

Tuesday, September 14, 2010

Going 3D

Here are the latest shots.



Let's see, what went wrong today:
  • Stuck the bracing on the rudder box in the wrong spot so I had to plane that off then re-glue it.
  • Got the sides on and as I was taking a picture I thought, 'How do I get the side tanks in?'. Luckily, they go in quite easy. Whew!
  • Forgot to notch out the side tanks for the bracing inside the boat. Not a biggie and easy fixed.
What went right:
  • Using picture frame clamps made putting the stern transom on nice and easy... and square.
  • Turned my router upside down in my vice and made a temporary routing table to make some space for the gudgeons on the rudder box.
  • Stripping of the tiller is going well. Should be able to re-varnish tomorrow.

Costing Spreadsheet, Shopping List

Here is a spreadsheet that I put together to help calculate the all up costs of putting together your PDRacer. It also forms a bit of a shopping list:

Shopping List

Monday, September 13, 2010

Not Such a Great Day

Most upset today as my second coat of varnish on the tiller (you know, the bit I said I loved making) 'crocadiled' the finish. I'd left it the prescribed 24 hrs before recoating but it still went wrinkly.

I'll leave it till tomorrow and give it a damn good sanding, leave it another 24 hrs, then try coating again. Hopefully it should be okay.

Daggerbox is painted, assembled and in. MAYBE tomorrow I can assemble the hull.

Sunday, September 12, 2010

More Changes

I found this page:

Perth PDRacer (sorry, that page has gone).

and that has a couple of good modifications, though some I'd be worried would make the boat a bit heavy. One mod I think I will make is to put in some reinforcement for a pair of rowlocks. I get the feeling that while I'm learning to sail I might need to paddle home occasionally.

Better Planning - Daggerbox and Tillerbox

Tell you what...

Next time, or for anyone else building a PDR MK III, build your daggerboard box first. Or at least as soon as the sides are cut so that you can get the correct profile for the box.

This is the bit that is hidden inside one of the side air boxes that the daggerboard (not a centreboard, not a leaboard, must be a daggerboard aka, the 'keel') goes into. This is because it takes ages to make due to the surface finishing that happens inside the box before you do the preliminary assembly. Have to do all this painting first because you can't do it when the whole thing is stuck together; you can't reach the inside of the box.

First you epoxy it, then you undercoat, then you top coat a couple of times. Each time you have to wait between 12 - 24 hrs for epoxy/paint to dry. As this bit gets as wet as the external hull, you have to make sure you paint and seal it well. You don't want it leaking into the air box.

I'd also buy the gudgeons nice and early so the tillerbox and tiller can be put together completely. That is a fun job to do. I've really enjoyed making that part and it looks really nice. Lots of nice, clean, varnished wood. Looks very nautical.

Friday, September 10, 2010

Changes...

Couple of things I've done differently to the MKII and from what I can see of the MKIII.
  • Think I've said it before; I'm going to undercoat with a quality exterior oil base and then topcoat with Killrust, not use a two part epoxy (see Dave Carnell's page on epoxy. Look down the bottom).
  • I'm not using epoxy adhesive. I'm using Selley's Platinum or Selley's Floor adhesive. Waterproof cross linked polymers.
  • I've added an extra two splines to the external side panels, so now there is a chine and a gunwale on the exterior sheet. I tried doing that without laminating two thin pieces whilst bending them, to put in the permanent pre-bend to match the fair curve. Both cracked during the install but generally should be okay. They're just providing a wider base for gluing the deck to. Not really structural and you won't see them.
  • I'm using 4mm for everything except the bottom, 6mm for that. Hopefully, that will keep the weight down.
  • I've put a hardwood face and tail at each end of the rudder and daggerboard to help protect the western red cedar. I know it will be glassed, that is just for extra protection.
  • I've made the decks 280mm wide, which will make the cabin fairly narrow. Still, you sit on the deck, not the floor and it's really just for one person, so that should be okay.

Wednesday, September 8, 2010

First Shots




Here are some shots of me gluing up the chine logs and the side panels all cut out.

One thing I have noticed is the MK II has chine logs on the lower curves and the MK III has them on the upper curve. You're going to get a lot of that. I'm becoming all nautical and navally, so words like 'chine log' and 'transom' and 'fair curve' are going to sailing onto the page.

I will also be moving to 'bells' to express time. Currently, as it's nearly 10 pm here, it's approaching two bells of the first watch.

My shed is a mess. Not because of the boatbuilding... it's just a mess.

My Puddle Duck Racer

We (wife and I) were driving past the canals and lakes here on Queensland's Gold Coast and wondered why we never saw anyone sailing on them. L turned to me and said 'You know, we should get a canoe and we could paddle around out there. It would be fun'. I heard '... we should get a canoe and you could paddle me around out there. It would be fun'.

I thought it would be hard work, so started to look around for plans for a small, cheap sailboat that I might be able to build myself that took some of the pressure off me paddling. The smaller the better and if it could be man-handled by just me into the back of the ute and into the water, so much the better.

Found the Puddle Duck Racer and eventually, the OZ MK II plans and decided that was the one. I purchased plans for the MK II from Mike then stumbled across the MK III and decided I'd give one of those a go. So, thought I'd better start a blog on the construction and adventures of my OZ MK III puddle duck racer (PDR). Everyone else does.

Though technically not a PDR as the hull shape is out of tolerances due to design improvements by Mike Storer (see 'The schism explained' below), it is the easiest way to refer to the little boat and have people understand what you're talking about.

For reference look in these places:
L's not that impressed as the PDR is a bit of an ugly duckling. If it works out and I like this sailing thing, I'm going for the Goat Island Skiff next.

BTW - the boat will be named after the little girl we sponsor in Mozambique through World Vision.