Daily update - cockpit preparations continued

 The work is progressing slowly, but steadily. I finished preparing the cockpit sides, final screws (5x30mm) are in and set in epoxy, limber holes are cut and glassed (I really like glassing exposed end grain for some reason, makes me feel warm and safe ;) ):

I'm varnishing the inside of the hull where it will be closed off by the cockpit:

I have 2-3 coats aft, only 1 coat so far forward of the bulkhead. I will glass the bottom of the "engine compartment" below the companionway as it will be used to store equipment (like tools or an anchor) and so it's going to be in extensive and careless use so something has to protect the bottom plywood.

I did run out of clear epoxy primer though (I'm using sealine 1:4 wood primer). No idea when the new batch will arrive, until then I'll switch to other things.

tot dan.

Daily update - getting the cockpit ready for assembly

 Before closing off the cocpit I need to finish  a couple of things:

- seal everything that will end up in the closed space - although I plan to install some ventilation (possibly even active) I expect this space to be a bit damp, so everything needs to be well protected.

- reinforce the transom joint - especially the attachment point of the lower rudder gudgeon. 

 

The Designed suggests a small(-ish) stainless steel angle plate screwed to the bilge plating as reinforcement. I went with laminated glass. 7 layers of 300g/m2 biaxial makes for about 2.5mm of reinforcement over the entire width of the bilge. A large fillet with a radius of about 2cm takes care of spreading the loads and the actual gudgeon will be back plated with something stiff (maybe steel or a GRP plate) and covering the fillet. I think this will spread the loads nicely.

This was the first time I used this type of glass - went fine, but it was fiddly. I tried to see how many layers I could saturate simultaneously - 2 was the number for me, 3 was too much (with the 105/205 combo), optimal was just 1. Good to know. I will practice some more before glassing the hull on some more internal reinforcements.

As for the pictures: I was working solo, so not much pictures from the actual work. Cutting this stuff went fine using regular household scissors but for the larger jobs ahead I ordered an electric pair on ***zon.

 

And here's what 7 layers of 300g biax looks like:

The white blotches are a result of me trying to go over too many layers of glass and not knowing what I'm doing in general. I'll improve eventually, hopefully before it is time to do the hull.

Let's see what tomorrow brings...

Heat box update

So. The winter was long and tumultuous, I did not get to work on the boat much. I did manage, however, to finish the heat box I was dreaming about while battling my assortment of cold resins. 

So I built an insulated box out of cheap(-ish) 15mm interior grade ply, 5cm foam insulation and 3mm plywood for interior walls.

With the box finished some enclosure for the thermostat electronics needs to be built:

The electronics and software are way overbuilt (probably where it does not matter) and possibly lacking in areas that will prove to be important. But at least I can reasonably safely heat resin in plastic bottles as the heater temperature is one of the many settable parameters :) Truly nerdy business, but fun nonetheless.

All together it looks like this:

Inside, a 230V, 200W silicone heating pad (from a 3d printer bed) - I did tear out the thermistor (no documentation) and replaced it with a DS18B20 temperature sensor.

... and after some last minute changes to tune everything up it's done.

 

Starting tomorrow I will get to work on the boat. I need to get it ready for transport within 2 months. Plan is to get the cockpit and deck done, glass the hull and paint it. A usable interior would be a nice bonus, but is non-critical in view of the constraints. I can finish after moving it to a new shop.

Updates will now be more frequent as I need to get crackin'. See ya.

Plywood passed a "test"

 Two years ago(!), when I bought the plywood for the hull and started the build I threw a scrap piece behind the shed in the muck, where it has been soaking in the rain and drying together with some leaves and mud ever since. This is how it looks like today:

 

No signs of mold, rot or delamination, that counts as good enough where I come from:) I'm not going to do the famous boil test. Not planning on boiling the boat either...

laters

Building the cockpit

 Today was the day I managed to start working on the cockpit. It is not too difficult, the cutting part, but it does require some planning as there are many corners and joints. I'm trying to make sure the joints will be load bearing in the direction that most makes sense for the particular joint.

I have cut out some venting holes:

The surfaces that will be walked on (and jumped on from the cabin top) will be reinforced with some beams - the design specifies 8mm plywood for all surfaces here and does not call for any bracing - I don't know, the 8mm ply seems a bit too thin to leave like that. It will gain some additional strength after it is glassed over, but I'm going to reinforce everything anyway. I will not be installing those before at least drilling the holes for the lower rudder gudgeon as it will be a pain trying to reach the transom through the vents in the bulkhead after everything is closed up.

The whole thing came out very symmetric, I could use the pattern I made for one side for making both pieces with a very good fit so, again, stressing out over the layout and the dimensions of the frames payed out again.

Tomorrow I'll start gluing everything up, but it looks like It will take more than 1 day as I want to cut some more limber holes in the side assemblies.

ciao.

A picture is worth more than a thousand words

Since no progress has been made as I'm waiting for some parts to get delivered (glad I still have that excuse at least), I'll share a link to the album with all the pictures of the build. No explanations, sly remarks or attempts at humor. Just pictures:

Setka Piglet album

enjoy.

Taking care of the cold resin problem

 It's been a while since last I updated my blog. Or even worked on the boat... Time to resume activities. But. Winter is coming. And it's getting cold in the shop.

Mindful of how much I hated working with cold syrupy resin last winter I decided I need to make a heat box to keep the glue toasty and thin. In the spirit of DIY and due to the fact I could not find one that would let me control both the temperature of the box AND the heating element (maybe they are there, but i'm sure they are expensive) I decided to make one. The heating element temperature needs to be limited for the obvious reason of not melting a plastic jar of resin, that would just be counterproductive. And I want to be able to use whatever heater I have at hand: light bulbs, whatever. I do happen to have a 200W printer heat bed, but that also likes to get pretty hot.

Requirements:

- Fun. Check. That has been had. The geeky kind.

- Cheap. Not sure if in the end it actually was cheap(-er) than commercial options, but hey, see point 1.

- Silent. None of that clickety-clack of mechanical relays. Hence a cheap chinese SSR comes into play. It is rated to 25A, I would not trust it beyond 10, in reality it will not control more than 1 or 2. Should be aok.

- Safe. As in: not melting down anything. Not the resin, not itself. So the temperature of the heater must be under control, and the temperature of self (as in: the solid state relay) must be kept in check. And since the latter is of the chinesium persuasion and likes to go up in flames - an additional safety (mechanical) relay comes to the rescue to disconnect the whole thing if overheated.

- Modular enough to be easily serviceable. That includes the micro controller - I picked an Arduino pro mini - simple, well supported and cheap.

- Simple interface: just one rotating knob to set everything (temperatures, hysteresis setting, saving defaults and the like).

The prototype (using resistors as heaters pressed against dallas temperature sensors) looks like this:

Instead of soldering everything on a prototyping board (which I considered) I designed a proper(?) PCB and had a well known chinese PCB manufacturer stamp out 5 of them (that is the minimal amount I could order). The boards will be arriving in a couple of days and if I did not make any oopsies in the layout I will have 4 perfectly good spares if anyone will be interested:

The code to go with the setup is published on github. I'm sure there is plenty of thermostat projects out there, but this one is mine and mine alone:)

Now on to trying to finish Piglet's cockpit. I'll post when done (in a few days).

doei.