My GS480 Build

[David Santistevan]

I am starting my ML Boatworks L&L Special GS480 Tunnel hull build. The kit arrived about a week after I ordered it and the cowl arrived the day before.

First observations are the quality of the laser CNC work was top drawer, very clean and not a lot of messy trees to clean up. The wood appears to be a high quality ply, all very clear and clean. Suitable for clear finish for sure. There were no instructions in the kit at all. James directed me a couple of blog posts with the various stages of assembly. The kit is simple enough to figure out the build, however it would have been nice to get the benefits of the experience of the designer in building the boat. Also it would have helped with seeing the final setup to do pre-planning or mods. At this point I don't really know what the final mechanical setup looks like.

Armed with CA and kicker I had both sponson shells built in about an hour. The foam filler came in a 2" pre-cut section and a 1" section which you will have to glue together to get the 3" you need. I layed up the foam for both sponsons to glue and let the dry overnight. This was the end of the first few hours of the build. I then started on the center section. The transon is made by stacking 6 layers of ply together. There are two (I believe) 1/4" holes in each of the transom plates. I assume these are for alignment purposes in putting together the transom. In the pictorial build they showed short lengths of brass tubing. Once again without instructions for any idea what the final setup looks like I am not sure what the holes in the transom are used for later if anything. If they are just for alignment I would have used dowls and let them glue with the transom plates. Then I could have just cut them off and sanded. More on this as I get closer to finish. The side rails of the center section are super nice, laser etched plackards. The inner reinforcement is a very attractive and adds a lot both in strength and appearence.

Before I started gluing the center section I decided to seal everything while it was appart making it easier to get a nice finish on all the parts. I use a finishing resin thinned 50% with alcohol to seal my parts, The acohol opens the pours of the wood, the thinned epoxy wickes in and then the acohol evaporates leaving a very sealed and hard finish. After letting soak for a few minutes I simply wipe the excess off with a paper towel. Then when dry lightly scrape with a single edge blade and you have a beautiful hardened seal. Afer sealing and scraping all the parts I was ready to begin gluing again. This time because I was working on the center section where the transom was and where the sponsons mounted I switched to expoxy to glue that together.

More to come.

D

 

[Mike Luszcz]

Shoot, I will call you tonight...it slipped my mind. PM me your phone number again, or give me a shout after 5:30pm est. Sorry about that. I was on a jobsite when you called, and forgot. Mike

Just read your post...Talk to Ron Shaw about setup, or James Beasley, or even Buddy Lowe. All three guys have top running hulls, and I feel they would help guide you with proper setup. I just do not run gas boats, so I rely on these guys to test them!

Instructions...I know, I know, I do not have printed instructions, however the build threads I do should help guide you. If not, please just let me know what you may need, and I will try and help. I am building one right now and can share more pics if you need it. Instructions are one thing I lack with a lot of kits, which is why I try to build a lot of them to help guide. I hope in the future to do better with this ongoing problem...sorry!!!

Not sure if I sent you this or not..

http://s42.photobucket.com/user/spoonefcrx/library/GS480?sort=3&page=1

Also, the holes in the transom, are for a 1/4" dowel to help line everything up..then just sand them back. I used brass tubing back then as it was what I had on hand.

Mike

 

[David Santistevan]

Thanks Mike, no need to apologize, I am just like to document my experiences with boats. So far this one is a beauty.

D

 

[Mike Luszcz]

Thats cool. I will shoot you a pm in a minute. Been a busy 24 hours! Mike

 

[David Santistevan]

Where was I, oh the center section, I chose to seal the center box before going any further to give a complete finished looked so that a little bit. Once that was done i built the center box using expoxy this time and mounted the transon. Everything lined up perfectly and it's is pretty hard to make a mistake. Once the center box was done I had to glue it the the floor decking. Now there are lines etched in the floor telling you where to glue things, I just weighted and tape it down and it was done. The remaining stringers and head were all very simple. So at this point the entire center section of the boat is built. I still need to glue the foam in and glue the deck down but that is an all-in-one shot I will probably get done this evening.

I just need to finish the sponsons now and I will be ready for final assembly....Hope my motor and leg get here soon....

D

 

[Beau Parsons]

David

Post some pictures I like to see what this design looks like, I may want one sooner than later.

Beau

 

[Mike Luszcz]

Just PM'ed David a few times. With how well the full frame up versions of the smaller tunnels has gone, I am going to work on a full frame up version of the gas tunnel as well. Seems like the way to go! Mike

Greg...I just gotta spend the time! That is really the bottom line is sitting down, and doing the writing. I have so many new designs I am working on I am so worried about testing them instead of getting the instructions done!

 

[CapeTown73]

Hi Mike,

Please excuse my ignorance but what exactly is a 'full frame-up' version of the GS480 ? How does it differ from my kit?

I finally re-started my GS480 build process again this morning after a more than two week delay while we were moving and getting settled in again, and have completed the gluing-in of all 16 blocks of blue-foam into the sponsons. I may do the trimming of the foam with my band-saw this evening or maybe tomorrow. Then the sanding.

Really enjoying building this kit!

Kind regards,

 

[Mike Luszcz]

Wennie, please view the new 33.5" tunnel I am building..it doesnt require all that foam shaping stuff..Its internal structure is framing. It allows for easier building for guys that do not have the equipment to handle wood over foam builds. The original GS480...your kit, is kind of a hybrid structure. It has some frames, but its main structure is the foam core. With the full frame up, you just drop in a few blocks of foam for floatation, and you are done. Check out this build thread on the px335...and do understand..I did all that in 7-8 hours!!! With wood over foam, it use to take me 3-4 weeks due to the glue on each piece of sheeting requiring dry time!!!

http://www.intlwaters.com/index.php?showtopic=56931

 

[CapeTown73]

Thanks Mike, now I understand and it makes a lot of sense!

My scratch build 45 F1 tunnel was built like that and you're right, its much easier not having to glue in and shape all the foam.

But I'm still very happy with my current GS480 and looking forward to complete it in time for the start of our new season on 3 August.

 

[Mike Luszcz]

David, Due to time right now, I don't want you waiting around for me to design the frame up GS480. I am however working on a GS480 for a local (had the kit for over 6 months, and just now getting rolling on it). Here are some build pics for the sponsons. Most seem to be fine with the center section, and there is plenty of pics already about that, but the sponsons I am gonna slow down, and do a short guide...Here goes:

Once you have your frames in place and CA'ed, you can cut up your foam into the blocks needed to fit between the frames. Then, epoxy coat the frame, and the foam where it is going to make contact with the frames. I actually did that, then glued the outside strip on all at the same time. I used CA at each end of the outside strip to hold it down agains the foam. I load a lot of epoxy up on the foam behind that outside strip so it has a good bond.

 

[Mike Luszcz]

And I woke up this morning, and hotwired the top deck foam down:

Then I set up my badsaw so I could properly cut the foam core that makes up the main ride pad. Please note, you can ride the fence from the sponson transom up to the second furthest frame forward, but at that point, you need to start pulling the sponson away from the rip fence as the angle pushes the blade closer, and closer to the outside strip. From that second frame at the front to the bow, you will use a disc sander, or block and hand shape it. Its very flat in that area!

See how you ride the wooden 1/8" fence down the sponson keelson, and it forms the proper dihedral in the foam:

From this frame forward, you will start pulling your sponson ever so slightly away from the wooden fence, making sure your blade doesnt cut the outside strip!

See here, my sponson is away from the fence, keeping the outside sponson strip safe.

This is how far I got this morning. This evening, I will show you how to sand down that front area of the sponson foam, and show you what to use as a guide while hot wiring your non trip foam area..then, its ready for some sheeting!

 

[dion smith]

Great pics and tips Mike!!! Can't wait to build one

 

[Mike Luszcz]

Here is some more on the GS480. This shows how to do the hot wire for your non trip foam. First, find one of your ride pads, and you will need to tape it, clamp it, whatever is needed to hold it in place so you can do the initial cut with your hotwire foam cutter. Once the excess is trimmed, you will then feather the ply on the outside strip so that it has the same angle as the non trip. See the pics:

Go ahead and sand the top side too:

 

[Mike Luszcz]

OK, more got done this weekend. So, you have your foam sanded, and ready for the non trip. You need to first, tape your sponsons together:

Once they are taped together, you can glue on the left and right non trips, and let dry. The reason for taping the sponsons together is so you do not warp the inside sponson keelson. This forces them to stay straight while the non trip is glued. Once its on, your structure gets much stronger and will resist deflection. Here is the non trip glued before trimming:

And sand the edges:

Now that your non trip is finished, its time to add the primary ride pads. Take note to how the rear section of the ride pad is taped on. This is done on purpose to make sure the tape is not lumpy..you will see why soon:

Now, you just finished taping up your sponson ride pads, but nothing has cured yet...Go ahead and put each ride pad against each other, and tightly wrap tape around the sponsons. This will ensure the left and right ride pad are nice and straight without rockers. This is why we only put enough tape at the rear to hold in place!

 

[Mike Luszcz]

Ride pads are on..now use your sanding block and stanley sur form to sharpen the inside sponson edge:

Once your inside sponson primary ride pad was sanded sharp..its time to measure for the secondary ride pad. This measurement is 1-5/8" from inside sponson toward the outside. Do it in two places, one near the rear, and one probably 13" or so forward. This will make sure your secondary ride pads outside edge is nice and parrallel to the primary pad:

You can just see the tiny black dots:

Now glue them on!

Finished bottoms:

 

[Mike Luszcz]

I actually got the top decks on yesterday, and thought I had pics. I dont! I epoxied them on, and wraped them with tape as well. They are untaped now, and ready for edge sanding. After that, the hull will be ready to bond together.

 

[dion smith]

Hi Mike,

Thanks for the great build tips!!! What do you use as a guide when shaping the front part of the main ride pad foam to keep the angle true, or is this part done by eye,

Cheers,

Dion