Getting a perfect surface with wood?

[LooseGoose]

If Coosa is too heavy and rough, then you might want to look into acrylic sheet material. Colors are available, so no finishing required. Framing/fixing points can be made from square tube aluminium, which can be bent to conform to your hull shape and bonded with adhesive and fasteners. It's also easy to weld. Scribe panels and affix to frames.

Here's a very very interesting finishing technique for painted or varnished interior finishes i stumbled across.

https://youtu.be/PpUBzF0LSnM

Good luck! Sounds like a very interesting project.

[Chotu]

Originally Posted by LooseGoose

If Coosa is too heavy and rough, then you might want to look into acrylic sheet material. Colors are available, so no finishing required. Framing/fixing points can be made from square tube aluminium, which can be bent to conform to your hull shape and bonded with adhesive and fasteners. It's also easy to weld. Scribe panels and affix to frames.

Here's a very very interesting finishing technique for painted or varnished interior finishes i stumbled across.

https://youtu.be/PpUBzF0LSnM

Good luck! Sounds like a very interesting project.

That’s a pretty interesting idea actually. Very light weight and it seems like it would go up quickly. Acrylic is nice and shiny looking. Definitely some application for this. Especially in the shower area.

[Fore and Aft]

Chotu what about outdoor sign writting panels? They are 1mm aluminium painted gloss white, 2.5mm plastic infill then 1mm aluminium painted gloss white. We have them on our ceiling and they still look good after four years. They cut easily with a jigsaw.
This is a data sheet on spray putty. It works well and gets good results considering it is not an epoxy. Sort of surprised me when I was first introduced to it 5 years ago.
https://conceptpaints.com.au/sites/d...y%20Pink_2.pdf
Cheers

[CassidyNZ]

@ Chotu - how thick is Formica in the US? Not a silly question because the Formica here in NZ is really thin and lightweight - I just redid all the counter tops in my boat and I cut the Formica with ordinary domestic scissors (actually used an old pair of my sewing scissors).

Certainly the stuff I used would not scare me from a weight perspective. That said, to skin the whole interior of a 50ft cat would scare the heck out of me from a cost perspective - this stuff is not cheap

[MicHughV]

I have one word for you...

West System Epoxy....

Ok, that was three words..

[GRIT]

Originally Posted by MicHughV

I have one word for you...

West System Epoxy....

Ok, that was three words..

You are obviously not aware, but: This thread exists due to the fact that Chotu is highly allergic to Epoxy.

Cheers.
Paul.

[MicHughV]

ok...no epoxy then.....

Home Depot sells these formica covered pieces of wood intended to be cupboard shelving.....the formica is on both top and bottom....the shelves vary in width...I'm guessing 12-18" x 6' or so, they are about 5/8" thick or so. The formica is typically white, though I have also seen an off-white color.
If you cut them to fit some unusual space.., you can also purchase this white formica tape that has a tacky glue on the back. You just press this on your cut edge and voila....a dressed edge.
The formica is as smooth as a baby's butt. You can cut several pieces to lay them side by side if you need...the straight edges will give you a very smooth joint.

Trust that will erase the epoxy idea.

[MicHughV]

"Im not sure if your allergies extend to varnish, but varnish also makes a good wood end grain sealer. ie, if you cut the formica shelf, you can dress the cut edges with varnish.

[MicHughV]

...finally...while I'm at it....if using formica shelving and you need to attach it to something...Home depot also sells these small little white buttons that you place over a screw head to hide the screw for a clean finish. These little buttons are intended to go over a philips head screw with a flat head. They fit into that cross made by the phillips head pattern. So you can screw this panel into what ever you want and dress it with the vinyl edge tape and buttons.

Not sure if this provides any help for you, but I gave it a shot.

[Buzzman]

Formica or Laminex don't go round curved edges terribly well in DIY situations.

Those pre-edged, curved-edge counter tops kitchen manufacturers used are formed in a factory and under conditions probably not possible to achieve on a boat interior fitted in-situ.

Glueing either is also a PITA as you have to use contact adhesive, and getting the two (nearly dry) surfaces to 'mate' is tricky, and the slightest, tiniest error of movement can destry a whole panel.

Ask me how I know!

Most kitchen manufacturers today use a polyurethane sprayed finish to achieve that 'long-lasting' finish you are looking for. It dries semi-gloss, but can be polished if you require high-gloss.

And PU is a MUCH harder surface than pain. Equivalent to epoxy fnishes or better in terms of hardness and resistance to wear. It's used on kitchen cupboard doors and some benchtops as well.

Given the epoxy allergy, this is probably something worth pursuing.

Fit all the cabinetry in stick-and-frame with cheap single-faced ply (so-called marine ply is usually double-faced - i.e. both faces are 'fine grade veneer'), but as you almost never see the inside surface of cupboards up close or shiny, so any tiny imperfections in the laminate are virtually invisible, or easily filled and hidden. Single face ply is MUCH cheaper.

[Note: to clarify, the ply has veneered surfaces both sides, but only one of them is top grade, 'fine veneer finish', the other is a B-grade (not A-grade) finish. Plywoods are often referred to as A-A, A-B, B-B, B-C, C-C, C-D, or D-D grade - from 'millionaires yacht' down to 'hide it behind sheetrock shithouse' quality.

The only thing to check with the supplier is that the glues used in the manufacturing process are 'A-Bond' glues. This means waterproof resorcinol formaldehyde or similar modern adhesive.

One really useful trick with stick frame and ply cabinetry is to use slightly large sectional size 'vertical corners' and 'horizontal edges'. So the stick used at a 90-degree direction change, whether cupboard edge or bench edge.

You then router the *inside* edge of this to the thickness of the plywood, and then router the outer edge in a bullnose. The resultant long-grain timber edge is MUCH easier to finish than the rough, multi-layered edge of any plywood you'd otherwise leave exposed. It's also a useful trick it fou are going to plan in any concave or convex vertical surfaces, as you can clamp the edge of the ply very tightly into the rebate and leave the clampos there until the glue is completey gone off, with no risk of the tension in the ply 'popping' the glue off.

Another good trick for such curved vertical surfaces is to use bendy ply, which has the plys going int he same direction, but can be either across the sheet or along the sheet. Across the sheet is best for cupboard sides that you want to have a curve in them.

But you'll need a good quality router and preferably a router table (or local timber machining shop with a spindle molder who can do this for you *accurately*.

Well, you did say you wanted the interior to still look like a 'modern plastic finish' rather than a piece of 18thC kitchen furniture....curves are good.

Especially where a bench ends near a doorway or stairs, for example. And you may want to put curves in the ends of stair treads down into the hulls so they aren't totally rectangular, like the stairs on the outside of a house. This is much easier to achieve with thinner plywood, and especially bendy ply, though I'd probably used long-direction-bendy ply for stair risers, if the curve is in the riser.

Then, once polyurethane-glued in place and sanded and faired smooth, get the local kitchen builder to drag his PU spray equipment down to the dock (or even an automotive sprayer in need of a job) and get them to PU spray the entire boat.

This is NOT a job for a beginner. Do NOT attempt this yourself. It requires specialist expertise but is REALLY quick. He won't be there for more than a few hours and will do the entire inside of the boat in one hit. But you'll need a ventialtion blower to such the PU dust out of the hull or he won't be able to see, and it will get on the finished surfaces. Essentialy, you need to turn the interior of the boat into a 'spray booth' with ducted extraction fans. Set up takes a while, but actuall spraying is quick.

I've seen kitche cabinet guys spray kitchens in-situ, but that was in a project home that was spotless and huge, so the overspray disappeared. Inside a boat, I'd want ducting, whether spraying paint or polyurethane.

Get a local carpentry shop (not a kitchen factory - a proper joinery shop, like one that makes timber-framed windows) to show you what I mean with the corner-support sticks run off with a bullnose edge and an inner rebate for the chosen ply thickness. Make the rebate a cigarette-paper shallower than the ply, becasue it's easier to sand the veneer down to match than it is to fill and hide a tiny 'step'.

AS good joiner will appreciate this and understand what you're trying to achieve, and should give you accurately machined timbers for your edges.

But use hardware-store-bouth 1 x 1" for all other supports.

I'd use 3/16" or 4mm ply for sides and dividers, 1/4" if theres a load on the edge, and 3/8" or 10mm for counter tops and stair treads, but there must be some support at least every foot, so a pressure point load is never more than 6" from a support. For example, the support for a galley bench 4' by 2' would look like a ladder frame with one extra-large longitudinal side rail - the larger sectional size edge with the rounded over bullnose and rebate on the inner. the other rail is probably going agaist a hull side, so doesn't need the larger sectional sixe, but might need tabbing underneath for extra support. Or use 2 x 1" inside of 1 x 1" along the hull side.

Does that all make sense?

[MicHughV]

I built my own boat from the ground up, a 38' ketch, some many years ago. I didn't know squat about much of anything when I started, and barely knew which side of a hammer was the handle, but it's fair to say I learned, often the hard way, overcoming numerous obstacles in the process and I succeeded and that boat became my home for the next 15 years while I bee bopped around the oceans.

Trying to finish a boat interior without epoxy glue is going to be challenging, especially so without wood working skills and allergies, but other options do exist.

When I was building my boat interior, I discovered my local high school had a wood working shop that offered evening classes for adults.

I signed up. This gave me access to a wonderful variety of shop tools plus a talented teacher, who showed and taught me how to do a variety of wood working projects. This was a blessing to a very young and naive me and I signed up for ensuing evening classes until my boat was complete. A helping hand is a wonderful tool to be treasured.

Besides the teacher, I also enjoyed the company of other adults there doing various and sundry home projects. They all took an interest in my boat building project and often came by to not only show me how to do something but also lend a hand.

I might suggest searching around for a similar situation. A lot of high schools have wood working shops and may have evening classes.

Completing your own boat is not an overnight affair. Mine took almost 3 years. A little patience and fortitude goes a long way and help can come from many directions. I owe my successful build to many, many people.

[Buzzman]

Another tip I forgot, to add to those above, is if you are doing benchtop edges with 'plan view curves' (i.e. looking down from on top, there is a curve in the edge) such as where a benchtop might 'return' to a doorway, you can laminate thin strips of timber around a form to get the shape of the curved edge, then add the routered bullnose round on the outside edge, and the routered rebate for the ply 'top' on the inside edge, using a portable router.

See sketches attached to get an idea what I mean.

The form to achieve the curved, laminated edge for the benchtop can be an old door, or sheet of 1" ply, and the 'pegs' against which the strips of 1" x 1/4" are bent around can be blocks or round pegs cut from an old broomhandle, screwed down vertically.

Add waterproof polyurethane glue between each strip, and clamp.

For tighter bends you might need to steam the strips in a steam box, Google how to do this, it's not hard. A length of 6" diam PVC plumbing pipe blocked at both ends, with the nozzle from a steaming kettle introduced into one end and a small hole at the other to allow cooled steam to escape. A few lengths of timber stuffed into the 'steam box' for an hour or so is usually enough to make them bendy enough to curve into complex curved shapes, such as bench edges.

You can also use this for the edges of curved stair treads. Then use bendy ply for the riser. It helps if you router a groove into the underside of the tread for the riser to 'slot' into.

Another method for stair risers they *can* be mechanically cut by a method known as 'kerfing' the back side of the riser, to enable it to be forced into a curve. This works equally well in ply as in solid timber. Basically a series of close together vertical cuts that only go part way through, leave the 'face' veneer intact.

[Chotu]

Thank you very much for all these ideas. It’s quite helpful to understand a little more about some of these standardized techniques.

McHugh, It took 3 years to build a boat??? Or was that just to do the interior?

I do have all the tools necessary. A nice router with all the bits too.

I welcome all input here and will be thinking about the techniques over the next few months on quarantine before getting back to it. Need to get the boat out of Florida too. Way too hot there to do interior work without air conditioning. Interior work is best done in cool climates.

Can’t seem to afford any docks for it up north though so I still need to figure that part out as well.

[MicHughV]

Chotu, I built my boat from the ground up, including the hull and deck, which were built from steel. Aside from wood working, I also had to learn how to weld, having never done that before. The hull and deck took about a year. The remainder of the time was the interior, and all the bits and pieces that go with it.

When I started, I naively thought I could build the whole thing in 1 year with $9K, all the money I had. Ha, was I in for a big surprise.

I chronicled my boat building endeavors and the first few sailing years in a book I wrote. I have several photo's in there. I started to build it when I was in my 20's. I had big dreams and little money. Mistakes I made were many, but I never gave up. The book is not just a technical how-to, but gives a glimpse of the trials and tribulations of such a project.

I understand this forum does not allow the promotion of one's books, but if you are interested I can contact you by PM. Let me know.

[gonesail]

good marine carpenters don't use filler.