32 inch F1 Tunnel build: Cozy F1 T800

[Dirk Jan]

Time for another build log of a F1 tunnel hull. I designed and built the Cozy F1 Tunnel 7 years ago already. The build log can be found here:

https://forums.offshoreelectrics.com...nel-wood-build

This time I designed a 32 inch hull. Setup will be 6S with a 3674 SSS 1650kV motor and 120A esc.
It will be an outboard setup with TFL large leg.
Speed estimate / goal is 55mph.

I took my experience from the Cozy F1 into the T800. The sponsons are wider and have less angle, to improve cornering. The hull and sponsons have a seamless deck and the tunnel has a lowered bottom, just like the real F1 Tunnels.

The hull I designed in Autodesk Inventor. I plotted the drawings and started to cut the ribs.

First update:














Verstuurd vanaf mijn SM-G970F met Tapatalk

[Dirk Jan]

And some more pictures. The build is much further already, so I will do a recap here, with frequent updates .













Verstuurd vanaf mijn SM-G970F met Tapatalk

[autolex]

Beautiful work! I love all of the detailed pictures. I too have some inventor experience (now use revit for work).

looking forward to the build!

[Dirk Jan]

Thank you Autolex!

Here's the next update.

As mentioned in the first post, the build is already in advanced stage. The boat hit the water successfully already
I need to make some minor updates on the drawings, before I will share them for free!

Starting the mid section with bottom extrusion, for a lower c.o.g.
The mid section bottom is made from 1.5mm birch plywood.



Using aluminium corner profiles for perpendicular angles.



Transom added, 4mm birch plywood.



Connected the sponsons temporarily to get an image of the hull!





Comparison with my Cozy F1, just under 24 inches hull length.

[autolex]

beautiful structural work! what are you using to cut the plywood?

[Dirk Jan]

Thanks! I use a hand saw old school style.

[lilbigmacky]

That's old school for sure. I hand cut a rigger with way less pieces and didn't want to touch a saw ever again by the end of it. Ever thought about laser cutting?

[Dirk Jan]

Yes I considered it, but I like old school / hand crafting. Also, I save some cost this way

Verstuurd vanaf mijn SM-G970F met Tapatalk

[Dirk Jan]

Next update.

Continuing the mid section. I designed one big compartment for all electronics.



Adding the lowered bottom of the tunnel:





Overview so far:





Starting with plating the sponsons:



Verstuurd vanaf mijn SM-G970F met Tapatalk

[Dirk Jan]

Next steps, plating the sponsons and laminating:









2 sponsons together:



Start laminating with 80gr/m2 glass weave:





Verstuurd vanaf mijn SM-G970F met Tapatalk

[Dirk Jan]

Continuing:



Laminating the electronics box:



Hull assembly so far:





Fitting the outboard leg:



Finished the steering servo plate:



Verstuurd vanaf mijn SM-G970F met Tapatalk

[Dirk Jan]

Continuing:



Laminating the electronics box:



Hull assembly so far:





Fitting the outboard leg:



Finished the steering servo plate:



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[Alfa Spirit]

Beautiful job, very clean. Congratulations.

[Dirk Jan]

Thank you Alfa!
Next updates:

Laminating the bottom. I made a rond in the inside corners of the center extrusion, by thickened epoxy.







Extending te backside left and right:









Verstuurd vanaf mijn SM-G970F met Tapatalk

[Dirk Jan]

Determine the position of the steering servo, with steering rods:



Hull overview so far. Loosely assembled:



Making a template for gluing the sponsons to the mid section:



I made a small wooden block to measure the sponson angle left and right, to be equal. The stripe on the block should align with the bottom of the angled section:



Glued and clamped together (not too tight):

[autolex]

BEAUTIFUL woodwork! I can definitely say i'm not this talented (or patient!) keep up the pictures!

[Dirk Jan]

Thank you Autolex

Next update:

Filling the sponsons with foam board.



I made a template from paper for the deck plating.



The deck is from 0.8mm birch plywood. I managed to apply the deck in one piece.







I chose for the SSS 3674 1650kV motor; it is affordable and I heard good stories about SSS motors.



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[lilbigmacky]

Looking great so far. Do you have cowling for the outboard motor?

[Dirk Jan]

Yes, cowling will be home made, for outboard as well as the main cowl/ cockpit and it will be shown here lateron!

[Dirk Jan]

Another update, starting with a comparison between the Cozy F1 and Cozy F1 T800



Bottom side with lowered mid section:



Time for applying laminate, 50gr/m2 glass cloth. I used the deck template again.

[nocebo]

This is awesome! Really amazing work and cool to see it go from a concept to reality.

A question on your inventor modeling process - do you start my modelling the overall shape/profile of the hull and then later build out the framing? What do you use as your reference for sizing of various hull components?

[Dirk Jan]

Thanks Nocebo and good question about the design.

I used the actual F1 Tunnels as reference and I took a good look at rc F1 Tunnels for the length - width - height ratio.
As I made the smaller Cozy F1 already, I took that experience as well. For example, I wanted wider sponson ride pads with less angle, to improve cornering. Also, I wanted the sponsons and deck smoothly transition into each other. That's why I started the design with a sketch of the transom, including sponsons. Next I made a mid plane and sketched the deck layout from the top. Next, the actual sponsons and deck were designed separately from the main sketch as reference.

[Dirk Jan]

Next update; I designed the cockpit / cowl in 3D CAD. I will make a mold with wooden ribs and foam in between. On top of the mold I will directly make the cowl from carbon fiber.



Finishing the front-mid section:





Installing the Turnigy 120A Marine esc. It is positioned besides and below the steering servo. I made a support from ply and mounted the esc with double sided tape.



As the mid box is very large, I put a cross bar between the lipo and other electronics. The lipo is a 6S, 4500mAh 60C.



The hull so far, including steering linkages.

[srislash]

Beautiful work

[nocebo]

Thanks Nocebo and good question about the design.

I used the actual F1 Tunnels as reference and I took a good look at rc F1 Tunnels for the length - width - height ratio.
As I made the smaller Cozy F1 already, I took that experience as well. For example, I wanted wider sponson ride pads with less angle, to improve cornering. Also, I wanted the sponsons and deck smoothly transition into each other. That's why I started the design with a sketch of the transom, including sponsons. Next I made a mid plane and sketched the deck layout from the top. Next, the actual sponsons and deck were designed separately from the main sketch as reference.

Ahh i understand, Im assuming you then sliced the solid to create individual sketches for parts for the framing members? Been thinking about doing a design for a while, but every time i sit down with a blank sketch in Inventor, I dont know where to start. You've done awesome work, looking forward to seeing it run.

[Dirk Jan]

Thank you guys

@Nocebo: I didn't design the hull as a solid, but I used sketches in planes and also used 3D sketched lines for the sponson sides for example.

I started with the transom, including sponsons and added the lines for the length of the sponsons as well:



Added the shape of the hull-mid section:



I made a solid for the sponson sides and I added 3D sketched lines for the sponson shape:





Added the ribs between the 3D sketched lines and made them as separate parts:



Built the mid section of the hull from the sponson lines and bottom sketch:



Finally, assembled it all together to make the design complete. Of course it took me a lot of fine tuning and modification to get the hull shape to my liking.
I hope it helps you making a start on a hull design. You could also design a solid like you said; there are many ways!

[Dirk Jan]

Complete hull:

[nocebo]

Thankyou so much, this is exactly what i was looking for. Youve done a great job on these models, they look really clean and neat.

Ill give it a go following your method - might have to start with a small mono first though, a bit easier : )

[Dirk Jan]

Here's the next update.

I made the battery tray from birch plywood and laminated both sides.



Preparing the hull for paint:



Starting the paint:





I started with the cowl mold as well:

[Dirk Jan]

Finishing the paint on the hull:







And finishing the mold for the cowl:





I laminated 2 layers of 200gr/m2 carbon fiber cloth and 1 layer 50gr/m2 glass cloth to finish it smoothly.
I put a non-carbon part in, for receiving the transmitter signal and gps signal.
Before laminating, I waxed the mold and applied PVA film.
The cowl released from the mold without issues: