Monday, June 5, 2017

Deck Sheathing

I have been sheathing the decks recently.   The horizontal surfaces get the worst punishment and I wanted to protect them.   I bought two big bolts of stretchy synthetic cloth at the local Memorial Day Flea Market for a few bucks and proceded to roll them out on the decks.


  I found little splinters trying to rise up and push up little bubbles under the cloth, so  I started wetting the plywood, rubbing a cloth over it against the grain to grab the splinters and lift them, then sanding again to cut them off.

 


   I wetted the whole thing down with water and spread the titebond III, then spread it around with what we used to call a "weenie-roller" in my days on the paint crew.     

  Now, this business of wetting down with water seemed rather foolish to me at first.  I have imported the passage from Dave Zeiger's blog.  


Application of Fabric plus Water-Based Pucky

Application consists of the following steps:

  1. Sweep and wet-tack for a dust-free deck
  2. Lay out fabric (may be overlapped, but abutting is sufficient and smoother)
  3. Wet out fabric (Yep. Water... drippy wet)
  4. Paint on pucky (may thin somewhat with water, if necessary for low-drag)
  5. Dry
  6. If not satisfied, repeat from 3 (a bit of weave left provides texture)
  7. Prime and top-coat

The first round of 1-4 is the primary adhesion step. As the water dries out of the weave, waterbourne pucky wicks (is drawn by capillary action) down into pores of the plywood substrate, creating a permeating bond interface. Subsequent layers build to coat and fill the weave.

On a warm, dry day, water evaporates quickly. If the fabric is drying ahead of you, consider keeping a water-brush on hand to refresh the wet. Without that water, wicking is reduced, and glue may not dilute and penetrate the fabric or wood surfaces for full adhesion.

At the end of the first pass, the fabric is only lightly bonded, however, and can be fairly easily torn away. It is reenforced by subsequent passes, however, and the result is firmly attached.

Consider whether to leave some weave for texture (thin matrix), or fill past the top of the weave for longevity (thick matrix). In the latter case, you might consider added texture in the topcoat.

My only semi-eddicated opinion is that green (not completely cured) layers bond better. Thus many layers can be applied in a single day. I especially like to prime over a green layer, in effect gluing the primer to the matrix. The whole seems to cure well over ensuing days (possibly even faster than the generally indicated 24 to 48 hours).


 I mean, how can wet wood bond better to glue than dry wood?   If there were some great adhesion advantage, wouldn't they tell you to wet the wood whenever you tried to glue it?   

  Regardless, I found the wetting to really help in positioning the cloth and make everything go smoothly. I can't imagine trying to do it on a hot day with everything dry.  

rolly-rolly la la la
aft deck done
Fore deck done
Starboard coach roof done



Big Stretch Test


 


   I am looking for something to seal the windows with.  Being 7 feet long, they are going to expand and contract with temperature.  From what I can determine, we are looking at 1/4"- about 1/8" either direction at the ends, where the expansion and contraction is greatest.  I was turned on to "Big Stretch" as a possibility, and I wanted to test it to see.    

  It claimed a two week setup time, so I made this test piece....


Had I-gor sand it well...

          

And set up this testing scheme, letting it dry for a month. 


 I put this goal, 1/4" of one-direction movement, which is twice what it should theoretically have to endure.   I put a nut on that little black carriage bolt and started cranking....


  The pressure was too much for a little hole in 1/8" acrylic. New approach.



Now we are pushing rather than pulling. You can see the new goal drawn on the plywood.




  Here at almost 1/4" past the goal, it looks stressed, but not coming loose.



Another 1/8" and it finally ruptured.

You can see here that it stuck very well to the wood, but not as well to the super-slick acrylic.  It could bear some roughing-up with some 220-grit, perhaps.  

All-in-all, I'm optimistic about using this product on the windows.


Tuesday, May 30, 2017

Rudder Hardware



     Finally got the rudder stock hung on some hardware that met my most important criteria:


  • Bulletproof
  • corrosion resistant
  • very cheap


  First, I cut some bands of metal out of an old hay baler with my wet saw.  


  I used to make a living with that thing.  Now I use it for fun.

Then, I cut a groove in an old stump and laid the bands across the groove and whammed a metal bar down over them so that they would fit around the rudder stock.

Who needs a fancy hydraulic press? 


I cut some bar out of an old chair.


  Then I straightened it and clamped it in place on the bands around the rudder stock.


  I had my dad weld these up.  I am so friggin' helpless!

 

  

  Here they are painted with coal tar epoxy.  A lot cheaper than having them galvanized.  The gudgeons are pieces of 1/2" galvanized pipe that I threw in the stove to safely burn away the zinc.  I filed out the internal ridge and found that you can insert a piece of pex pipe and leave a little bit protruding, which you can heat with a propane torch and mash down to make a perfect little top hat bearing.  No metal on metal, hooray!


I wanted to be able to boot the tiller where it goes through the transom because of rain and spray and bugs getting in through the hole. To have a lip for the boot to attach to, I just cut the lip off a plastic bucket and heat-formed it around an elliptical plywood mold.   




Here it is in place over the hole that the tiller goes through.


   That same evening, Ale broke a dish glove- manna from heaven!!   Looks like it fits perfect. 








   Here is the rudder stock installed with the tiller in place.  You may notice that the shape is a little different than what it was in the photo above.  In the mean time, I realized that I had had a brain fart when I was designing it.  I had put the pivot at the water line, which would have the stock dragging through the water all the time, so I cut it down.   There is also a little skeg I installed under the transom to get a little more distance between hinges .  The tiller is bolted to one side only so as to allow the rudder to swing all the way up so I can leave it in place on the highway.  

Speaking of the rudder, remember  I said it was too darn heavy?  Well, I tested it to see:


  I put a string of gallon jugs on it and dropped it into the pond to see how many it pulled down.  Turns out it was about ten pounds to the negative.  Of course, that weight doesn't have to sink the whole thing, just the underwater part, so I took off seven by drilling a 1.5" hole and plugging it with plywood. 


   While it does little for total displacement, it may make it a little easier to pull up.  





PS....

  I made this blog thinking of my family and friends mostly here in the US and Canada. However,  I have been fascinated by seeing the page traffic I get coming from Australia, the Phillipines, Thailand, etc. If any of you from those places read this, I encourage you to comment or check out my new contact page and send me an email telling me how you came to find this blog of all things. 

Thursday, May 11, 2017

Quick Update

I've gotten a couple things done in the past couple weeks.



Here is the Tabernacle all glued up with its bearing plate glued and bolted on. The metal strap is copper pipe pounded flat for lightening.  Everyone has their opinion on this matter.  Lightening is such a mysterious phenomenon, it's hard to know who to believe, but my money is on some kind of grounding and bonding.  At least when things start going BOOM BOOM BOOM all around, you can look at your first mate and say, "Honey, it's OK.  I have taken measures."


  Here it is installed. I had the disconcerting experience of having the 5/16 nuts pop loose after I torqued them real good on 5/16 threaded rod.  I bought a bag of these from Fastenal and they are all kind of loose. I wonder if their threaded rod isn't machined light as well, perhaps to be more forgiving of having the threads all boogered up when you cut it??  I will have to address this.


I don't usually go in for testing, but deck sheathing begged for it.   Here are some odd bits out of the bargain bin. There was a stretchy polyester, a double ply blend, a plain, thin cotton-poly blend of the very most common type, and some cotton canvas. My money was on the cotton canvas, but it was not to be....

     

  I followed Dave Z's procedure for laminating, skeptical as I was.  I-gor did the heavy lifting, as you can see here.  The double ply stuff was too hard to wet out.  The cotton canvas resisted wetting out and raised bubbles as it dried. It would be a poor choice for this.  The other two wetted out nicely and had a good feel.



After three coats, we were good. The thin, purple cotton-poly would have been ok after two coats and the third really slicked it up too much for my taste.


  I made the test piece into a sled and drug the kids around the driveway for half an hour, trying to replicate light to moderate abuse.

 


There was very little damage to any of the samples except the cotton canvas, which tore badly.  Whew!  Glad I didn't go with my gut on that one!   


Wednesday, April 19, 2017

Real Carpentry





  After all this fooling with plywood, I am now making a lot of trim pieces. And there are several on the boat:

toe rails-                      4
hand rails-                   2
walkway coamings-    2
outer wales-                2
inner wales-                4
hatch board retainers- 4


That's 18 by my count. I started with the forward toe rail.



Here it is laid out.  I think I was subconsciously inspired by the aluminum toe rail on my buddy Jason's Mirage 18 to make lots of little holes. Bad move. Easy enough for a robot to mill out of aluminum.  A lot of work in wood.




Here I am drilling all those little holes. I was half way done when I changed my mind, so I just pressed on. Get it?...pressed on? never mind.



Here they are, roughed out with a chisel.




For the curves at the ends of these, I opted for a series of straight cuts with a hand saw.



Then rounding it all off with a big ol' horseshoe file my dad gave me from when he was a farrier. It's a lot easier than doing it with a jigsaw.  I find that cutting really hard wood with a jigsaw puts tension in my whole body and makes me really uncomfortable.

I rounded off the insides of the holes with the handy dandy router (thanks for that gift, Tommy)



and put my lovely assistant to do some of the tedious sanding.



Lucia got in on the sanding, as well.



The outer wales involved two scarf joints each.

Damn, I'm good

Would you have been able to pick out the joint if it weren't for the screw mark on the wood?



This board had a little wane in it right at the end, which made the perfect base for a scarph joint.  It worked out!


 The inner wales were a little less tedious to make, but a little more dangerous, it turned out.


See all those little pieces glued on the end grain?  I cross cut dozens of  them on the table saw against the fence. I had a little push stick to send them over onto the floor, but toward the end, one of them got a little caddy-whampus between the blade and the fence and, ZING! That little sucker flew back and got me literally right between the eyes.  My safety glasses (thanks for reminding me, honey) absorbed the blow and fell off my face in three pieces (but never broke, strangely).  Oh, how very lucky I was, not to have taken it in the mouth! That would have really added to my pirate look.  From then on, I stood well out of line with the blade.

The fine students at Carroll County High School planed me this lot of white oak.


Here we have staves laid out to be gang-cut for the tabernacle, trying to use the prettiest wood from each board.



  I tried to order them so that the bows of the respective staves cancelled each other out.




Here they are glued up with LPU glue.  Right glue for the job?  I dunno. I'm always doubting.


Cami chiseled off the foamy squeeze-outs for me. It was a fun weekend for the kids.

Ready for pucky


Making a table with the window cut-outs

Boat as playhouse

The weather was nice, so we took their boat out for the first time since last fall.  This is an Auray punt scaled WAY down from Bolger's interpretation. I built it for them two summers ago.