New build

[KonaKing]

And my next tool, in the process of being built.

Ok I give, some sort of foam cutter?????????????? Do tell.

I am thinking of triing to build something new this winter but do not know what. Maybe a quad fin and try vacum bagging.

[Surfdad]

Yep! It's actually a copycarver. The principal is based on a pantograph. You may remember those as kids where we would trace the outline of a picture and the arm would contain a pencil and would duplicate the drawing. I principally just mess with one design, but tweak small aspects or the materials. I've found it REALLY hard to duplicate a shape consistently. This tool will allow me to trace one board and it will cut out or duplicate the board INCLUDING the fin boxes!!!!!! Sort of a poor man's CNC.

Keep me posted on the quad, no matter what I did I just couldn't get them to work. Drivey as anything, but all that fin area really locked up the tail.

The bag is a great deal of fun, this is the board out of the bag this morning and it currently weighs just a hair under 35 oz. The deck lamination is 2.5 oz of 4 oz cloth and 2.5 oz of resin. I know that some talented and experienced laminators could do that by hand, but I couldn't spread 2.5 oz of resin across the deck of a board. The bag allows even a garage hack like me to get a 1:1 matrix with as little as 2.5 oz of resin.

[harv]

Okay, like I said, I know nothing of the board builing terms. What does the "bag" mean?

[Surfdad]

The "bag" is shorthand for Vacuum Bag. The process was mostly stolen from the wood working guys that attach laminates to cabinets and the like. Normally, folks that build and shape surfboards apply fiberglass directly to the foam by hand, squeege it out and let it cure. The vacuum allows a much tighter a lighter/dryer lamination by applying equal pressure across the entire surface of the bag.

This is exceptionally useful with epoxy which has a much slower cure rate than with 'old school' polyester resin. I'm not a half bad laminator, but I'm not great either. If I were attempting to laminate the deck of this board by hand, it would have probably taken me 8 oz. A good 6 oz of that would have remained on the board, the rest being waste that falls off the rail laps. Developing a resin/fabric matrix that is balanced provides a board that not only is lighter but has better riding characteristics for folks like James that can take advantage of it.

A picture of the bag and pump below, and James.

[Surfdad]

This is a picture of the board with the application of what is referred to as a hotcoat or sanding coat or fill caot. All refer to the same thing. It's basically a very thin layer of resin that is then sanded down to a rather smooth finish in preparation of a gloss coat. The lamination is somewhat dry and this secondary layer of resin will "fill" in any exposed or dry parts of the weave.

In a traditional surfboard lamination, the step following this hot coat would be a gloss coat. However, I am going to be painting this board much the same way that an IS is fabricated or the Surftech line of boards. I'll scuff this hoatcoat with 220 and then apply catalyzed primer (several layers) instead of the gloss.

[Surfdad]

Epoxy is a little persnicity. If you leave any oils, from your hand, on the surface you can get fish eyes or zits. Sooooo...my process for hotcoating is to lightly sand the surface to knock any junk off the surface. Then I wipe the whole surface down with Denatured Alcohol. After the sanding I don latex gloves to avoid transferring any crap from my hands

My last trick for the hot coat is the elimination of the bubbles that can appear. I use a 1" bristle brush and tip the bubbles as they appear.

What you can't see on the bottom of the board is the masking tape that keeps the epoxy that runs off the rails from getting on the bottom, which is already done.

[Surfdad]

The hotcoats are done, and the board weighs just a shade under 40 oz. I still have to install the fin boxes and I believe that I'll have the board right at 40 oz (2.5 pounds) going into the paint phase. My paint won't arrive until the 29th, so I'm a tad ahead of schedule. The paint scheme is intended to be all black with an overlapping set of red fading to orange flames that are pinstripped outlined in yellow. If I can keep the addition of weight from the paint to 1 pound then the board will have a final weight of 3.5 pounds.

A snippet of what I hope the bottom of the tail will look like.

[harv]

I love flames. Can't wait to see finished product.

[Surfdad]

I can't wait to see it finished!

Fin boxes in. First pic I am marking the cut. I don't care about the visible marking as I'll paint over them. Second picture I am test fitting the boxes and the final picture the boxes are epoxied in and curing. I didn't get a picture, but I placed tape from the tip to the rail to hold them in place at the proper cant during the cure.

This isn't the normal way to install futures boxes, they are design to go UNDER the lamination, but the bagging process makes that difficult.

[jwanck11]

How do you measure for the proper cant for the fins and set them specifically in that exact position. I build rockets and find that fin placement is essential for proper flight - tolerances on rockets that travel ~12000 feet are quite small indeed. Wondering if there is a trick that I might learn.

[Surfdad]

I can imagine that the toe and cant of the fins is extremely important at that speed. For surfboards the margin of error is typically 1/16" +/-, less than that and it's pretty hard for most folks to even feel it.

Luckily, the cant on the fins is preset by the fin manufacturer. The tab on the bottom of the futures fin will reflect a 3 degree cant if the box is installed level with the bottom of the board.

So...for me, it's pretty easy - just level everything and cut.

For the toe, I use 1/4" or 3/16" on a side. For that, I just establish the centerline of the board and then a right angle off of that to establish the trailing edge of the fin. Then measure forward to mark the leading edge toe. Depending upon the board, the trailing edge of the fin is set at 15 or so inches apart - 7.5" on a side.

Not NEARLY as technical as your application.

[jwanck11]

Thanks... yeah especially as I work with cylindrical objects.

When I build 3 stage assemblies it is even more fun. I usually dont even paint em.

[Surfdad]

I can't even imagine setting the cant on a cylinder, you must have some 120 degree template to align the fins?

Back to the build. I want my flame graphic to flow over the boxes rather than having some garrish white box poking out of the middle. Sooo...I used Bondo to create a smoothie! I've taped over the fin slots and set screw holes, I'll go back and touch those up after the paint is dryed.

[Surfdad]

Off to the tedious part. Lots of sanding and prep work and then off to the various layers of primer, base coats and finally the flames. I do believe this board will be OK at around 5 pounds, but that is 2.5 pounds of foam and glass and 2.5 pounds of paint.

[da.bell]

Wow, that is definitely light... Why are you spending so much time on this particular board? I don't remember your other builds being this detailed or taking this much of your time...