Friday, April 30, 2010


We hiked in snow flurries to get a different view of Delicate Arch (16 m tall) now across the valley. The desert in the spring is very interesting. We had sun and hot, sun and cold, wind with tremendous, visibility-cutting dust storms, snow . . . you name it, we had it.

Below, taking an email break. Email and nature might not seem to mix, but when service is infrequent, ya do whatchya gotta do.

The La Sal range on the eastern edge of Utah. I've always loved the contrast of the red rock and the white snow at this time of year.

We camped at Fisher Towers. Too close to the towers for a great picture (opposite direction), but great spot to spend the night.

We left the van in Grand Junction, Colorado, and flew home. I'll return in a month and continue on a trip towards California and then home.

Meanwhile, back in the garage . . .

When I cut out the profile of the rudder, I cut right on the line. With the centerboard, I left a margin so I could use the LB to smooth out the irregularities of my cutting.

The blank was thicker than the final board, so I took the whole thing down to the thickness that I wanted for the upper portion that remains in the case and will need to be flat (all dimensions at this point are minus the anticipated cloth).

I'm convinced that the groove around the edge is critical, and made this one even bigger. I put some black pigment in so that I could easily see it while sanding.

Now it was time to test out the preparations. First, have a plan on how not to get confused as to which line is which depth, and then set the router. (If you need to get in the mood, watch a video of a master making a hawaiian longboard -- "I know the board in the blank, and I know how to go get it")

For this first attempt, I considered the grooves to be markers for the final amount of material I needed to remove. I chose a narrow bit so they wouldn't run into each other on the leading-edge side and also would maximize the flat area to run the router on.

Then with a larger bit I worked from the outside to the inside, removing material with a stair-step pattern and a couple islands that were supports for the last swipe of the router (each stair step removes material at a depth of the next highest step so that the lower groove remains).

After some easy passes with the stiff long-board, it really took shape. I found that using some foam scraps cut to shape were great holders during this stage. You can see the trailing epoxy edge now showing.

Not quite sure why it seems hard to find, but it took a while to source stitched carbon at 45-45. I finally found it at Composites One (thank you Tom!) and because they allowed purchases in small quantities, chose VectorPly C-BX 0600 and 0900. While not the exact weights specified, it looks like great material -- and I could actually get it!

Here I've routed out the groove for the UD and am cutting the double-bias (DB) (UD does not actually go next to the foam).

The material was great to work with, nothing like the DB glass that falls apart so easily. As I always do, the piece was wet out on plastic, then moved while supported by the plastic. Here it is just off the vacuum table.

The idea is for the central piece of glass and this first outer layer to maintain the flat or 'trueness' while shaping the other side. The carbon at the trailing edge is placed exactly as I want it. I held the leading edge back (and thinned the foam for the extra layer) and will run an extra tape layer down this edge and over the top. After covering the other side, the whole foil will be wrapped in a single piece for the final layer.

Here's the second side after literally 2-3 minutes with the longboard using the grooves as a guide - not much left to remove. While I was anxious at first about being able to control the router and get an 'exact' groove, this was really not a worry. The longboard fixes nearly everything. If you make an error on the outside of the line, the longboard easily takes off the small high spot. If you make an error on the inside of the line, a slight low spot will remain. If you can still see it after two layers of carbon, then it will easily disappear during final fairing. Either way, the grooves provide a guide to the perfect shape.

Hard to show in a picture, but it really is a great shape.

Second side in the bag. I found this 'tube' bag material used for surf boards - it's useful for parts that shouldn't be against the table. Just cut to any length and close the ends.

I left the trailing-edge carbon long on this side and will cut/sand to shape against the strengthened epoxy groove that has now been exposed on both sides and encased in first layer of DB.

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