Beam update

Sorry guys - I've been working on the beams, working on the shop, building a deck and trying to finish up my apartment. 

I have neglected this blog quite a bit...

I have in fact been working on the beams for the last year, I'll just go ahead and post a link to progress photos and do my best to update this as I proceed.

Thanks for your understanding and patience.

Beam Build Progress

Beam Anchor epoxy fill

Due to the voids I created last time around making these beam anchors, I was going to make absolutely sure it didn't happen again. For starters, I added just enough glass fibers and Cabosil to the epoxy to thicken it to a "honey" consistency. Then I put the epoxy container into the Vac-Mobile and manned the controls for almost 15 minutes to get the air out of solution.

After that, I slowly poured the mixture into the troughs before smoothing it over and then running a heat gun over the surface to remove the little bubbles just under the surface.

Once I was satisfied with the fill and level, I added some peel ply and let it cure.

Same for other side.

Rebuilding beam anchors. Trying a new blade

The next step in rebuilding these anchors is attaching the pivot tube to the top of the panels.
The tube has a smaller diameter than the thickness of the panels, so it has to be centered properly.
The instructions show one method of attaching them which involves laying them down flat and using a packing piece to lift the tube off the surface a bit so it sits centered on the panel.

I did do it that way the first time around, but when I checked on them later they had moved around while the epoxy was curing (newbie mistake) forcing me to cut them off and re-glue them.

This time, I wanted to try a different approach which was easier and worked a lot better for me.

Both panels clamped together and set vertically with some pieces of scrap lumber to create a "wall" on either side.

Some spacers set in place to center the tubes and some tape to hold everything in place while the epoxy cured.

In the meantime, I started researching different saw blades for cutting the anchors later on.

I am still a bit surprised at how effective this method was so "Thanks again, Arno!"

I found a blade with diamond tips that was purpose designed to cut cement board and thought this might be the perfect thing to use.

New blade mounted on table saw and set up to do a cut on one of the "junk" pieces from last time.
I wanted to see how this blade would perform before screwing up another set of anchors.

Unbelievable!! The cut was nearly effortless and I had to force myself to SLOW DOWN.
It almost felt like I was cutting through a candy bar

Nice smooth cut, little to no heat build up and not a lot of dust either.
I'm really happy with the results!

After the cut, I removed the blade.
You can see that most of the paint is still intact and it still looks almost new

A bit of paint removed from one of the cutters is all that happened on this cut.

Thanks Arno!

Arno contacted me after that last post and suggested I use a fine toothed saw blade to cut the LFS Beam Anchors next time. So in the shop last night I set up my table saw to see how this might work by re-cutting one of those messed up pieces. As it turns out, just using the the blade I had in there (Standard Ripping Blade) worked just fine! I have some better blades picked out that I'll be ordering later on.

(I just love the community support among builders!)

After confirming this would be "the" method to use, I ended up using the saw to cut the core panels for the next attempt at making these pieces. I also cut the panel I made a while back for the float bow gluing surface.

I did wear a respirator, hearing and eye protection when doing this job since fiberglass dust was all over the place for a while there.

After getting those cut out, I got the router set up to mill down some foam panels to the 5/8" (15.7mm) thickness required. Then ran them through the table saw to get them cut into size.

Since this is my second time doing this job, I learned from the previous attempt to add 1.5" (38mm) to the width of the blank. Doing so allows you to cut off and discard the rough outer edges of the blank while also negating any concern regarding kerf allowance.

The foam is now glued to the core panels and set to cure.
Tonight I should be able to clean up the edges and get the back edge rounded over and sanded smooth. I should also have the replacement G10/FR4 tubing delivered soon.

Everything is going so much smoother this time around...

A nice practice cut

Clean edges, no tear out

Moving on to cutting the core plates for the Lower Folding Strut Beam Anchors

Foam panels milled down, cut to size and prepped for gluing to the core plates 

Junk parts...

:(

This past Friday morning, I picked up my Lower Folding Strut Beam Anchors from the shop.

Apparently, I spent a lot of time and money making junk parts...

I was upset about it for a day or so, but there's not much I can do about it.

These parts will not be used in the boat, but I'll be hanging on to them to use as "practice parts" when setting up the router for the next step & etc.

You can clearly see the major problem in the pictures below...
Next time around I'll make the Hi-Density mixture a lot thinner so that it can actually be poured after degassing (like a very thick syrup) instead of being troweled in place as a thicker mixture like these were.

The other issue was the use of a water-jet machine to cut the parts.
The guys did a good job but it was the wrong tool to use to get the blanks sliced up.
I'll have to look around for a different method next time.

Currently I'm thinking of locating someone with a big wet-saw, or maybe even use a diamond tipped bit on my oscillating saw.

(I'll be able to check that method on these junk pieces...)

Anyway, I'm starting from scratch to rebuild these parts.

Huge Voids in Hi-Density Fill

Water Jet cutting is not the correct method to use for these parts.
Notice the concave section of the tubing.

Layup in place for rebuilding these parts.

Best infusion to date

I'm still on the learning curve regarding resin infusions, but every time I get to do one I learn something new and try something different.

In this latest example, I was building the Lower Folding Strut Beam Anchor Base Plate.

I spent one evening getting the fabrics prepared and everything laid up correctly.
I then applied the Vacuum Bag and pulled down the pressure. One small leak near a pleat was quickly isolated and fixed and then I turned the pump off and let it sit overnight since it was too late to mess with resin, but I did take the time to run the resin amount calculations:

34" * 16" = 544 sqin x 8 layers (of 18oz) = 4352 total fabric area
4352 *.31grams of epoxy per square inch = 1350 grams of mixed resin

1350/1.30 = 1038g PartA
     (1.30 is the 100:30 mix ratio)
1038 * .30 = 311g Part B

(This is an approximate amount required to fill the fabric itself, plus the feed lines and the amount left over in the consumables with some left in the bucket to ensure no air is pulled in near the end)

Note: I ended up with about 120 grams of mixed resin left in the bucket.

The next day after work I found that I still had a very good seal and had only lost 15 millibars over a 24 hour period.

I mixed up the resin and fed it into the stack via the small 1/4" (6mm) line to throttle the flow.
The wet out was really good and even.
Total infusion time was right at 40 minutes.

Once the resin had soaked into just over half of the Enka Fusion on the vacuum side, I clamped off the inlet and outlet tubes leaving the tube connected to the VacMobile (turned off) to keep a vacuum on the line itself.
What I was wanting to test/validate this time around was the "self leveling" characteristics of the excess resin. Since the inlet side of the infusion will always be a little heavier and thicker I was hoping to see that excess material flow into and fill up the Enka Fusion.

In this case, it worked perfectly as expected!

Infusion nearing completion.

If you look closely, you can see the difference in shading near the left side of the stack.
The darker green area to the right is where the stack is fully saturated, while the lighter green areas on the left edge are still pulling resin in.
Also notice that I moved the Enka channel on the right side about an inch (25mm) over the fabric stack, this is not a problem since I've found that the resin will move in all directions (to an extent) seeking to fill the voids.

When I first started practicing infusion, I was under the impression that the resin would only move toward vacuum and would never move in the opposite direction.

Some part notes

Scraps of foam are used to create an inlet pad.
I use a Dremel tool to bore a hole through the middle and then I cut a flow channel underneath the part while a quick pass on the sander rounds off the edges.
Puncturing the vacuum bag for the resin inlet is the last thing I do before introducing the resin.
Doing it this way eliminates a potential leak source.

Vacuum consumables removed - Nice looking part!

And a close-up shot

Beam Carbon Anchor blanks curing

A sticky messy job that took about three hours to complete.

The beams are super critical to the integrity of the boat and the instructions stress a nice tight wrap (no wrinkles) so I really put in a lot of effort pulling the fabric very tight as I completed the wraps. Once that was done, I hung them both on a rod to lay up the remainder of the fabric before wrapping with Peel Ply. Both blanks received an additional layer of carbon to remove all doubt regarding strength. My final thickness measurement ended up right in the middle of the required thickness, so I'm happy with that decision.

Both carbon blanks are now hanging around waiting for a full cure before cleanup and ripping down to produce the sixteen pieces required for the next step.

Peel Ply removed to check quality (No bare hands on these pieces)

Final Carbon UD thickness should be 6.6 - 8mm

Nailed it!

Hanging around to cure while I work on planking the inner starboard float hull