Warren's Build Log, CAN 573

[Chad]

...I'd do the woven sock outermost/last, and use clamps to grab one end of the sock to hang from the ceiling, and add clamps to the bottom end as weights. The sock will compress the under-layers pretty nicely as you rub/milk the sock upward and down. Also, with the woven sock outermost, any sanding that nips into it isn't as critically important as would be the case with sanding into the unis (although you'll still want to avoid turning too much sleeve into black dust).

[Warren Nethercote]

Chad, I see your logic, although I am concerned that it would force me to ensure that the uni layers did not go beyond the trailing edge. A better solution might be to go my way (sock first) but vacuum bag, which would allow me to drape wider-than-necessary uni over the foil. Others seem to have done the layup successfully with the foils leading edge up and the vacuum 'bag' draped over the whole thing. I don't have a vacuum pump but a friend has offered to loan me his.

As a supplemental note, a final lamination of light glass cloth (say 6 oz) might be useful as a fairing layer, protecting the carbon fibre at the expense of extra weight.

[Chad]

It's very difficult to bag something like this without inducing wrinkles, and you really don't want wrinkles in uni.

Make a small mockup and bag a few samples first if you haven't done much vacuuming!

...or, make your core's trailing edge something tough (1/8" G10 or home made E-plate), hold the unis deliberately away from the TE (in staggered fashion even), and let just the sock go around the TE. Like this:

layup.pdf

[Warren Nethercote]

From pillar to post .....

My carbon fibre order hasn't arrived yet for the rudder so I used some of the left-over cedar to start building spreaders. I am going to use structural cedar cores with carbon fibre reinforcement - I have knitted tube that I bought for DN tillers and didn't use, and some remnants of 12oz CF uni left over from DN runner building. Thinking about 2 x 12 oz uni plus knitted CF tube. Should be plenty strong if Chad's estimate of C-Tech's CF-only layup is about 36 oz.

Dave at Competiton Composites suggested that the spreader brackets were large enough for me to do adjustable spreaders if I wished, but I would sooner have rigid ones. I have inverted masts twice using swinging spreaders, and lost one rig with a (swinging) spreader bracket fitting failure. So my spreader roots are sized so I can get a snug fit in the brackets after application of carbon fibre (it would be tempting to glue them in, but I am leery ....). The spreaders will taper towards the tip in both planes.

I have to think about spreader outer ends: Jon's totally captive shrouds are the acme of simplicity and reliability, although logistically awkward when first rigging the boat. Chad's conventional approach makes outfit easier, and is the norm, but depends on the lashing. Either way I am probably going the synthetic rigging route. (Jon: is your standing rigging synthetic or wire. It looks like the former in the picture, but I am not sure.)

[jray]

Warren, I used wire for all the standing rigging, 1/8" for the side stays and 5/32" for the forestay. Had the t-balls professionally fitted buy APS and used Sta-Lok fittings attaching to the turnbuckles. The only downside is that the stays cannot easily be removed for transportation. I haven't found it a issue yet but haven't pulled long distances.

[ryderp]

Here is a link to how I built my rudder foil: http://i550-381.blogspot.com/2012/07/rudder-foil.html

I basically did exactly what you are proposing, except that I used a pre-formed foam core from Flying Foam. I did the first layer of sleeving without vacuum bagging (described in the blog), and then bagged the rest. I had no problems with distortion of the layup during vacuum bagging. My rudder is actually the most "professional" piece that I made on the whole boat.

I use a rudder cassette (which I highly recommend) rather than including the gudgeons in the foil itself.

Phil

[Warren Nethercote]

Phil, my proposed approach is based on what you did - my apologies for not giving credit. I even thought about the Flying Foam blank, but the last time I went to their web site they announced that they would no longer ship to Canada, so I went the cedar core route. I would have done foam core spreaders too.

Incidently, today I did the first cedar core spreader using Chad's technique (well, not exactly): two layers of uni CF followed immediately (wet-on-wet) by a CF sock. Don't know how much detail the photo shows with the cluttered background. It was the first time I have done a wet application of a sock and I was surprised at how straightforward it was. Now I am waiting for my carbon fibre order to arrive, as the rest of my uni remnants are quite short.

[Chad]

I started using these guys' methods to do most sleeve-type projects:

http://t780.blogspot.com/2009/09/mastbau-salinge.html

Their build blog is pretty humbling, all around.

[Warren Nethercote]

Chad, impressive indeed! Don't know if you have watched much of their video, but off wind there is some pretty impressive (sic) trailing edge singing from the foils. Vuvuzela is perhaps a fitting name for the boat! It is the first 'handraulic' swing keel I have seen (but I am sure there are more).

[ryderp]

Warren,

I think that the cedar cores will work out great for you. I only used the Flying Foam cores to save some work in creating the foil shape. I think that the weight difference will be minimal. One note is that I ended up having to shorten the cord of my upper spreaders (a year later) because the main was hitting the trailing edge of the upper spreaders when on a reach or when the sail had a bit of twist in it. I could also have moved the shroud attachment point back, but it was easier to just take a saw to the trailing edge and then fill back in with epoxy and filler. No problem with the original design on the lower shrouds.

Phil

[Warren Nethercote]

My carbon fiber arrived and a friend loaned me his quirky vacuum pump, but my 'honey do' list got in the way of progress. Finally, today I used a cut-off from my rudder core to approximate a rudder tip and run a test piece with glass cloth laminates. The test turned out well, but I think I'll collar my wife to help with the real rudder, lest it turns into a Chinese laundry.

(Admin: I wanted to do a picture of the test piece too, but the site disconnects when I attach the second picture. The error message is 'This page can't be displayed.' The same thing happened when I tried to add the second picture by editing the one-picture version here. I have made multi-picture posts in the past ...... I will add it as a second post. Nope - it failed as a new post with a single picture. ?????)

[admin]

I just tried a test and yes, the 2nd image would not load. I'll start a ticket with netfirms, the web hosting entity. For now, just try doing it one post at a time, and remember file size is limited to 2 mb per image,

sorry for the inconvenience! --TF

[Warren Nethercote]

Thanks Tim. Here is the second image ..... both of them were about 180kB, so no size issues. I was very happy with the degree to which the laminate conformed to the test piece's 'tip'. There were puckers of course, but nothing like I expected. Of course, it was only 3 laminations of 6 oz cloth.

[Warren Nethercote]

Dirty little secrets ..... ever noticed how no one seems to write about how nasty it is to remove resin-soaked breather after you have vacuum-bagged something. About 2 hours getting the stuff off my rudder. Any advice to offer? I used a spatula, and was tempted to try a heat gun, but I think that might be a Dick Tracy move!

[Chad]

I usually end up using a putty knife, an old and slightly polished/rounded flat blade screwdriver, a fairly sharp wooden wedge or shim, and needle nose vise grips.
Polyester peel ply (instead of nylon) is usually a little stronger and easier to get started, and won't tear into little bits as easily.
There is another product, that is smooth with very tiny holes, that leaves a slick surface and comes off easily. It allows the epoxy to flow through to the breather/absorber layer, but its slick surface isn't suitable for secondary bonds.
If it was easy, any monkey could do it!

[ryderp]

The release cloth that I used (I think from Soller Composites) was coated with silicone and pealed off pretty easily. I had to pull pretty hard but it came off in one piece. Actually the breather/absorber and the release cloth came off together in a nice looking "blanket".

Phil

[Warren Nethercote]

I was hoping to post an update of my latest rudder 'oopsie', but I am getting the 'Page cannot be displayed error' again. I am trying this from a different computer as a quick post, but don't have photos available here.
My rudder trailing edge turned out too thick even for an anti-singing edge so a made a glass extension with glass tape for skins overlapping the main rudder TE, uni-directional glass below that, and a filleting mixture core. The uni should make it resistant to chipping, albeit not as robust as the original configuration which had Gougeon 727 biaxial tape over the TE, followed by a carbon sock and then carbon uni. It also looks a bit funny, with the glass TE on a carbon rudder, but that is why they invented white paint.
I do have a photo, honest I do ...

[Warren Nethercote]

With luck, here is the photo described in the earlier post ....

[Hooligan]

Thanks for your great information Warren. I will be looking back on this forum as i progress with CAN#503.
Nick
Hooligan
CAN#503

[Chad]

Hi Warren,
I lost your email (sorry!), but here's the 30 degree chainplate frame I used, both for a "standard" decked boat and a round/pdx style deck, in dxf format.

Best,
-Chad

i550 ChainplateFrame.dxf.zip

[Warren Nethercote]

Thanks Chad!

[Warren Nethercote]

I have been picking away at stuff, but suffering from the realization that there was too much house maintenance undone, and needing doing. Oh well .....

But I have now got a rudder and a rudder cassette, although I must build a tiller before the cassette can be declared 'done'.

And I have spreaders at a similar state of development. I broke down in the end and abandoned my short uppers for something more like the normal proportions.

Both cassette and spreaders await completion of a tiller and GNAV rod before I clear-coat. I am going to try System 3 water borne linear polyurethane.

I am also picking away at organizing nesting for my frames so that I can get them NC cut locally. Thus my request to Chad for a usable file for his diagonal chain-plate frames, which I like.

[admin]

Wow, great job, Warren. Clearly some of the i550 circle have ascended into the realms of Higher Building , at least compared to my "workboat" quality launch.

Keep at it, man, and boyo boy do those house maintenance demands interfere....I address eight years of neglect instead of sailing these days!

[Warren Nethercote]

I don't know about that 'higher building' stuff. Some may wonder why I never take close-ups ....

[Warren Nethercote]

Rudder is done and now moving on to the fin for the keel and a gnav strut.

I trimmed the top of the rudder blade to fit the top plate (an old GRP batten) so I can see what the rudder cross-section looks like. My GRP trailing edge kluge is pretty obvious once you peak under the paint (blush). I also see a touch of asymmetry here and there, but who is perfect?