ML GSX338 V2 P Sport Hydro 1st Build

[mojoracer]

Hardware backers:
I hate blind nuts! I do travel races from time to time, and need to remove hardware for shipping. I have found blind nuts always strip out or fall off eventually! Working with washers and nuts in the tight confines of boats is a pain too. For this build I am using 1/8' aluminum plate material. These pieces will be drilled with a #29 drill and tapped with #6x32 threads. The back side of the plates have been scuffed up with 36 grit sander. This is to help the epoxy stick. Once the plates are ready to install, I cover the back side with epoxy. Coat your bolts with some grease and tighten the plate to the hull while the glue dries.
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[TRUCKPULL]

Hardware backers:
I hate blind nuts! I do travel races from time to time, and need to remove hardware for shipping. I have found blind nuts always strip out or fall off eventually! Working with washers and nuts in the tight confines of boats is a pain too. For this build I am using 1/8' aluminum plate material. These pieces will be drilled with a #29 drill and tapped with #6x32 threads. The back side of the plates have been scuffed up with 36 grit sander. This is to help the epoxy stick. Once the plates are ready to install, I cover the back side with epoxy. Coat your bolts with some grease and tighten the plate to the hull while the glue dries.
[ATTACH=CONFIG]158463[/ATTACH][ATTACH=CONFIG]158464[/ATTACH]

The other nice thing about backing plates and starting out with 6- 32 screws is:
If a 6-32 strips out the hole left in the plate is the exact size for a 8-32 tap.
The same is for a 8-32 striped hole it is now the correct size for a 10-32 tap

Here is a tool that carry in my tool box.
It is called an Electrician's Tap (because these are the only screw sizes that they use). It is a stepped tap 6-32 - 8-32 - 10-32

Larry

[mojoracer]

Assembly of the the 3 lumps:

Get your 3/8" wood dowel rod and cut 2 pieces 9.75" long. This will leave a bit hanging out of each side and can be trimmed off later. Before installing the rods, I used the sanding block to smooth out the sponson to center section interfaces. Make sure both the center and sponson side surfaces are nice and smooth so you get a tight fit. Now your ready to install the dowels.
I slid these into position, just lightly offset. I brushed on some epoxy on the areas that will slide through the holes in the components. Rotate and center your dowel rods into position.
Before gluing I test fit each sponson making sure everything lined up flush. Then I coated the center section sides with a heavy coat of epoxy. Once coated you can slide the sponsons onto the dowels. I used some more servo screws to fasten everything down tight! Go around all the joints and brush with epoxy. I had to use a bar clamp as shown to pull the rear of the LH sponson in tight on the bottom seam. Now it's looking like a boat!
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[ray schrauwen]

I use 1/4" thick material...

I'm just nuts that way...

I drill and tap after gluing without the top skin on in case it screws up, lol... Might drill one tonight...

Hardware backers:
I hate blind nuts! I do travel races from time to time, and need to remove hardware for shipping. I have found blind nuts always strip out or fall off eventually! Working with washers and nuts in the tight confines of boats is a pain too. For this build I am using 1/8' aluminum plate material. These pieces will be drilled with a #29 drill and tapped with #6x32 threads. The back side of the plates have been scuffed up with 36 grit sander. This is to help the epoxy stick. Once the plates are ready to install, I cover the back side with epoxy. Coat your bolts with some grease and tighten the plate to the hull while the glue dries.
[ATTACH=CONFIG]158463[/ATTACH][ATTACH=CONFIG]158464[/ATTACH]

[mojoracer]

Did some metal work at lunch time. Backers drilled and tapped, and a custom skid fin bracket fabed and welded. Drilled some holes in the hull and mounted these backing plates with epoxy. I use made in USA Speedmaster hardware on all my boats! Great products from some nice people in Florida. I'm using a .21 flat bottomed hydro strut and a 21 rudder. For the turn fin I will be using a Mojo Racing Products 40 size SS fin.
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[mojoracer]

Getting ready for the deck!
Before installing the top deck, pack the inside cavities of the sponsons with some flotation. I used an old Styrofoam ceiling tile. 1 tile will do many boats! Pack it in tight. It also helps absorb energy in collisions!
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[mojoracer]

Installing the sponson decks:
Make sure all of your top frames are free of any epoxy lumps from the build process. I sanded all the top deck contact areas before decking. I test fitted each deck and drilled my screw holes before gluing. This way every thing will be lined up before epoxy coating!
Make sure to coat the inside deck surface with a good coat of epoxy. Also apply a liberal coat of epoxy to the frames the deck sits on. Once epoxy is applied, I placed the decks on and ran the screws down. Everything pulled down nicely. I only had to use 2 clamps at the rear of the decks to close the gap at the rear outer edges.
I flipped the boat over and put some fiberglass cloth tabs on the portion where the deck meets the sponson heals or transoms. This is the curved area at the back of the decks. Not i put some heavy epoxy coat in the joint where the deck meets the sponson sheers. This area will be ground down quite a bit to make the finished bull nose shape! Having the hull upside down held the epoxy in the joint nicely! Let it dry over night!
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[mojoracer]

Trimming the sponson decks:
You now need to trim off the excess plywood from the sponson decking. I found a great Dremel tool for this. It's a carbide coated cut off wheel and it is quite an awesome tool to have. This thing cuts through plywood and fiberglass like butter! I picked this up at my favorite local hobby shop, Prop Shop Hobbies for $19. Well worth it!
I trimmed the outer perimeter with the carbide wheel, leaving about 1/16th of a inch to grind off with the sanding block. The rear curves needed to be trimmed back as well. I used a pencil to mark this curve, guiding it with the edge of my finger. Once everything is trimmed, I shaped the bull nose curve with the sanding block. Fresh 80 grit makes quick work of this process! I also ground the rear of the no trip sponson side flush with the sponson heel. Hand sand to finish your curve around the entire outer edge.
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[mojoracer]

Sealing the plywood:
I sanded and cleaned up the entire hull in preparation for this step. I used an electric leaf blower to blast all the dust out of the interior and exterior. I use Z-Poxy finishing resin for this step instead of West System. This stuf brushes out much better, and cost a lot less. I like using the higher density foam brushes to apply this. Foam brushes work well, and don't leave a bunch of bristles behind! I coated the hull inside and out and hung up to dry.
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[cybercrxt]

Well, you made quick work of that! Did the cowlings and dowels arrive yet?

[mojoracer]

Well, you made quick work of that! Did the cowlings and dowels arrive yet?

Yes! Unfortunately sent to office, and I'm not there today. I will get it tomorrow

[mojoracer]

Lay out time:
The motor I bought arrived today. Time to lay the components in and check CG. Had to package the 4S 4000 lipos sideways. Looks like the CG will be at the center of the fin. This generally works on all the sport hydros I have run over the years.
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[mojoracer]

Finishing the hull. I used some stinky Bondo to fill all the imperfection and screw holes in. After that I sanded the hull with 220 grit sand paper. I applied a coat of of automotive catalyzed primer. Now the external wood is sealed up.
I also installed the ledges for the rear hatch to sit on. Motor mounts have been started and the boat will be rigged out tomorrow! Getting closer....
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[mojoracer]

The rest of the kit:
The package arrived with the cowling, nose blocks and dowels.
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[mojoracer]

Installing the front nose pieces:
Trim the 1/4 round and bull nose parts to the correct length. I left them a 1/6th long and sanded to fit. The bull nose is taller than the plate it mounts to. I cut about 1/8th of an inch off the bottom and re-shaped the curve a bit.
Attach using epoxy. I chose to use screws run into the center stringers. I also used plenty of resin on the inside joints so the hell will be sealed. Fiberglass cloth strips were also added inside. This was a step that should be done before the sponsons go on. I did it this way due to the later arrival of the rounded parts. This concludes the major wood working!
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