Garden Tom Cat

[gregleetaylor]

Hello! Im getting ready to build William Garden's Tom Cat. The inner stem is 1.5". Im considering epoxying two 3/4" marine plywood pieces together to make this up. Transfer the full size Plan and saw it out. Pros and cons please? Thanks. Greg

[Jim Ledger]

Why not just laminate out of strips of solid wood. The ply would be a bad idea for a number of reasons. Here's two...

It would be difficult to shape.

The exposed end grain would be a constant problem and be impossible to finish well.

It would be weaker than a laminated piece.

Let's see pictures of your build when you start.

Good Luck

Jim

[mcdenny]

Another good option is to make the stem out of twp pairs of pieces of solid lumber. Butt joints are fine as long as the left and right side joints are seperated. This is less work and less messy than a stack of laminations but probably uses a little more lumber.

Plywood is miserable to plane and you will have a lot of planing to fair the stem to accept the planking.

[Ian McColgin]

Also it's harder to get the fastenings to hold well in ply. But I'd agree the biggest problem is moisture intrusion and rot along the fastenings at the plank hood-ends.

As I recall, Gardner has a plans for both dimensional and ply for various stems and frames of the Chamberlain gunning dory. When I costed it out, ply turned out to be more expensive, and that was back when quality marine ply was not nearly so dear as it is now. The scantlings were, as I recall, considerably heavier.

[gregleetaylor]

Very nice gentlemen, thanks to all and so quickly! I can see I'll have a great way to avoid some problems on this forum! Only build I have is McCarthy's Wee Lassie II which, although very long to completion, was a breeze and very satisfying to build. I plan to strip Tom Cat (one way to skin a cat?).

Lofting first...

[GregH]

I'm building an 18' version of Tom Cat, and I totally agree with all the above advice. FWIW, the stem is an important STRUCTURAL member- it not only provides an attach point for the forward ends of the planking, but is also the attach-point for the forestay. It is definitely NOT a member to short-change. I laminated both the inner and outer stems from 1/4" layers of white oak.

[darroch]

Leave a little room for springback...

[michigangeorge]

I'm building an 18' version of Tom Cat, and I totally agree with all the above advice. FWIW, the stem is an important STRUCTURAL member- it not only provides an attach point for the forward ends of the planking, but is also the attach-point for the forestay. It is definitely NOT a member to short-change. I laminated both the inner and outer stems from 1/4" layers of white oak.

Just wanted to add: use WEST G-FLEX epoxy to laminate the white oak pieces - the stuff really works well!

[esingleman]

Leave a little room for springback...

In my experience there is no springback with a glued laminated stem, I have made four of them so far, and each one I could place right back flush against the form. One of them was even made of only six 1/4 inch white oak laminations (although I pre-steamed them onto the form to get the curve started or else they would not have made it to the curve of the form without snapping), the other three were thin mahogany laminated stems without steaming.

Although having some extra room in case you aren't able to get complete clamping to the form or some other potential problems is a good idea.

Erick

[gregleetaylor]

All right gents, laminated oak sounds fine:
where do I get it?
Im in suburban Philly

[shade of knucklehead]

All right gents, laminated oak sounds fine:
where do I get it?
Im in suburban Philly

Do you need planed boards or rough sawn oak?

[gregleetaylor]

rough sawn is fine

[gregleetaylor]

have no steam box or experience in steaming (yet)

[shade of knucklehead]

Let me check at work tomorrow for someplace close to Philly.

If you can find a lumberyard you might find white oak, but its getting rare at lumberyards as are lumberyards getting rare.

I did find White oak at our local Lowe's a couple of weeks ago, the selection was very very limited though.

[wizbang 13]

I would double saw as in post #2. Not of oak.

[esingleman]

Here's a suggestion. First off, make sure your oak is white oak (it is decay resistant, red oak is not, but you probably already know that). Now there are people out there that will say there is difficulty bonding white oak with epoxy, and there have been anecdotal stories of epoxy glued white oak laminations de-laminating, however we don't know the full story on these cases (for example was the wood prepared properly, was it at the right moisture content, etc.). Regardless of the old stories, there is a new epoxy product from west system that is designed to work with difficult to bond woods such as white oak. It is called G-flex. Of course there is always the old standby, Resorcinol, but this glue requires a good clamping pressure, and a tight joint with no gaps. You could always use mahogany with regular epoxy, if still worried about gluing white oak.

When I looked at laminating the stem for my 12 1/2, I was going to go with many thin laminations of white oak, until I envisioned all of the strips I would be cutting and all the glue I would be spreading and dripping and cleaning up. So I decided to thicken the laminations to about 1/4 or 5/16 so there would only be six or seven laminations to glue. Because of the thickness, I steamed them and clamped them to the form overnight to get a partial curve set in them so they would bend to the form without cracking. I then spread on the G-Flex, and clamped them tight to the form. It glued up very nicely, however there were a few spots where there were tight gaps (< 1/32" ) that the epoxy filled. So if you decide to use thick laminations, make sure you use an epoxy glue, as it's gap filling properties will make up for small gaps due to insufficient clamping. Thick laminations take a relatively hefty set of clamps.

A steam box can be a PVC pipe with end caps, a drain hole, and steam entry hole, or can be a piece of clear plastic duct taped together with a steam hose stuck inside. You don't have to make an elaborate steam box, if this is the only thing you are going to bend. The rule of thumb for steaming time is one hour for each inch of thickness. I used kiln dried white oak, and I soaked the laminations for a couple of days before steaming them. I also let them dry for a few days before gluing them.

[gregleetaylor]

Allright on this. Ive gotten a bit ahead as the stem workand fit seems most challenging. Have to decide between laminating and overlapping. Prior build out west did overlap and doug fir for stem and all keel line members

[Dave Lesser]

Here are some photos from a Tom Cat build at the WoodenBoat School a couple of years ago:
http://www.flickr.com/photos/jdlesse...0141886/detail

It is cold-molded, not strip planked, but you might find some of the other details helpful

[willin woodworks]

Go to Tague Lumber. they have a yard in Philly on Easy High St and another in Media PA.

Excellent source for all things lumbery...

[gregleetaylor]

You guys are great!! Thanks. Great time savings and the build quality is going up even before the lofting!

[gregleetaylor]

I'm back at it. Setting up the lofting, stripping with 5/8 bead and cove x 3/4" northern white cedar. votes for or against adding molds to keep hull fair? Also, have four 1/4" quarter sawn white oak planks as exterior for transom to finish bright. Worried about gluing for adhesion (white oak thing) but not wanting to have purple colored resourcinol show through any small seams in the glue up. G Flex?

[gregleetaylor]

transom pieces clamped on form picture testAttachment 2133

[Alex Low]

Stem: Trad in Fir:

[m2c1Iw]

You may find this thread interesting, hope it's OK to post the link.

Mike

[gregleetaylor]

More good support on this forum; thanks! Have found a source of white oak. Have source of northern white cedar, bead and cove.

[gregleetaylor]

Thanks Alex! Your Silva Bay story was a big part in my deciding I could actually build this boat. I wonder if your blog is still available?

[Alex Low]

Hi Greg,

The original blog is gone, but I have my photos from the build. There is a messy version of the blog still up here: http://blog.boatschool.com/2006/

It requires some poking around to get all the posts in 2006/2007 sections.

If you want to know any specifics, send me a msg and I can find you some pics - the build is well documented.

I would love to know how the boat is fairing - she was sold to a family on the Sunshine Coast in Halfmoon Bay I believe....

Alex

[gregleetaylor]

Alex,

I was looking for wood on the west coast and stumbled on a supplier who knew Bill Garden well. His original Catspaw was available from his estate at the time... I hope she has found a good home also. I have been following another blog that is a nice documentary of a Tom Cat in Australia located from the link posted earlier on this thread. He is using the same strip and epoxy method I will be using. It has been quite a welcome experience to have the benefit of collaboration with this. I might go so far as to say the boat would not be underway without the lift it provides.

I don't know if what I am doing will be worthy of additions here as it's slow ( I work for a living and some nights I am just too tired to go to the shop) but it may just prove to be the life line for the completion. I have, Oh, say, 200 projects underway at any given time... But this one is right up at the front despite its size.

I do believe I'll give the documentary a try; I must figure out how to efficiently get pix to this site (right size 'n' all). Northern white cedar arriving from Cananda via UPS tomorrow needing to be scarfed but already beaded and coved. Shipping horrendous $! Figuring out how to make the steambox thing and have found a rough cut white oak source within a longish drive from here in suburban Phila.

Lofting very near completion, a real help already, and nails in body plan to transfer for mould making next. Best to all...

[gregleetaylor]

Cat Boat...

[gregleetaylor]

Lofting table support and shipment of northern white ceder from Canada stored for strip planking

[gregleetaylor]

transfer nails from lofting to mould 1st Mould

[gregleetaylor]

Advice please: I'm using white oak sheer strakes showing about 7" of edge set so i'll need to make a pattern/spile. the maximum width of the sheer will be 4 - 5" and the plank will be finished at 1/2" thick. Can I make each strake up of two sections scarfed togther (G-Flex) or would I be better off buying that really wide plank, about 13' long? Also, the rest of the hull is cedar so is there any special way to joint the cedar to the oak? The sheer planks will be finished bright. The plans call to cover the hull with bi-axial cloth. Is bi-axial transparent when set in epoxy?

What say ye sages?

[wizbang 13]

you can grind little triangles from the tops of those round top nails.
wont need to staple them , and they will stay stuck in the lift off piece.

[gregleetaylor]

Cool, I'll give it a go, good timing as I've got seven more moulds to go, thanks!

[BC Bill]

Lofting table support and shipment of northern white ceder from Canada stored for strip planking

Might I inquire where you sourced your cedar strips from?

Thanks, Bill