24.5" e-tugboat model- Bare bones, no photos, no plans, no parts, no instructions

[Frank v B]

Interesting project- My enabler Greg Cadez called and said he had parts of a tugboat model.  If I did not want it, he would throw it out. NFW!.  It ended up in the back of my van.

These are all the parts it came with.  Clearly a wood kit because the decks have printed planking.  I will finish it, put a small electric motor and RC equipment in it and take it to TooGood Pond in the spring.

Approach
- I scoured the internet for about 300 tug boat kits.  Could not find it.
- looked at 500+ images of vintage tugboats.
- have an idea of what this original could have looked like
- start building and design it along the way.
- fibreglass the hull to smooth out all the strip planking and make it waterproof.
- 50:50 rule will be applied liberally.*

Photos:
Here are the photos of what I received. 
- added balsa stringers at the deck level so I could see the shape.
- filled in the rear deck with two layers of balsa.  It was clearly a fantail stern.

Here's to the challenge.
I have added a photo of the Sanson which is close to the design.  My model is about 10 years older in design.


Frank

* 50/50 rule in airplanes is "If you cannot see it at 50 feet and 50 miles per hour, don't waste your time on the detail."

[Frank v B]

First step:
- built a rudder to what the stern would look like
- add the balsa rear deck and glue it in place.  This will clearly outline the deck and strengthen the balsa stringers.

Decisions made:
- the big central deck stringer will be removed once the deck has dried (black arrow in photo 24).  Access for the RC equipment.
- the rudder shaft and control horn will be added above the deck.  Will build a little box to cover it.  Reason- the fantail stern is so small it would be a waste of time.  Easier to adjust later.

Photos:
23- shows the balsa added to the stern to get its shape right. Also shows the new rudder.  The prop shaft and prop came with the boat.
24- the deck is fitted.  Needed some trimming.
25- deck glued and clamped in place.

Frank

[GuyOReilly]

Great project!
Looking forward to seeing it at Toogood Pond in the spring.
A "toolbox" or rear cabin will cover the rudder linkage quite nicely.
Keep us posted.

[Frank v B]

- Installing the front decks
- starting the planking of the hull.  Each plank was soaked in hot water for an hour.


Frank

[GuyOReilly]

Just curious, what type of glue do you use, CA or aliphatic?

[Frank v B]

Guy,

You're asking an impatient builder.... 5 minute epoxy!!  I use the good (expensive) Bob Smith 5 minute epoxy.  It hardens in 5 minutes and is rock hard in 15 minutes.
 
If I have more time (overnight) then I use JB Weld 5 minute epoxy which starts to think about hardening in 15 minutes but does not stick until after an hour and stays tacky for hours. False advertising.

I cannot use CA at home (wife's allergies) and aliphatic glue makes me yawn because it is so slow. 

Frank

 

[Frank v B]

Oops!  It is not a tug.  It is a fishing boat!!!

When assembling the boat and installing the deck house and hatch...it turned out it was not a tug boat (tugs have a wheelhouse in front) but a vintage (1940-ish?) fishing boat (they have the wheelhouse in the back).

Photo report:
36- The first time assembled.  The wheelhouse would only fit on the back hatch.
37- view from the top.  The white is the light weight spackling after a rough sanding.
38- Arrows point to two spaces filled in because the planking bulged outward by about 1/2" from the frames.  Installed new planing inside the bulge, the cut out the bulged hull.  The photo shows 2 small balsa patches (black arrows) at the transition points.  Easy to sand once the filler dries.

Frank

[Frank v B]

Fibreglassing the hull.

Here are the steps I use(d) in fibreglassing a hull, wing or fuse.
Assume all joints/voids have been filled and sanded.

Materials- Photo 64- I used:
- 15 minute epoxy (Bob Smith Industries),
- a cheap 2" brush,
- rubbing alcohol (Rexall),
- a mixing container.  I used an empty Ferraro Rocher container because it
has rounded corners so it is easy to empty/clean
- 1/2 oz fibreglass cloth.

step 1- Photo 66- drape the fibreglass cloth over one half of the hull.  Let it overlap everywhere by about an inch.
step 2- mix the epoxy 50/50 per normal then add rubbing alcohol slowly while stirring.  The consistency should be that of water. 50%-50% EPOXY and rubbing alcohol.
step 3- Photo 66- dip the brush in this mix and gently drop the wet brush onto the fibreglass cloth.  This locks the cloth in place.  Each next brush stroke needs to radiate out from this first spot.  Wet the cloth all the way around even at the edges.  Let this cloth hang down (see photo 67 at the bottom of the upside down hull) and make sure the epoxy goes onto the cloth beyond the hull.  When hard, it makes it easier to cut with a #11 Xacto blade.
step 4- let it harden overnight so it is cured.

This whole process took 20 minutes.

Tomorrow I will trim the excess cloth and do the second half.

Frank

ps: check out this earlier post.  It has a link to a terrific video on fibreglassing a hull from the AMA (US).  https://temac.ca/smf/index.php?topic=8898.0

[Frank v B]

Fibreglassing the hull Part 2

Step 5- knife the excess cloth off the first half. Photo 69. Lightly sand with a relatively fine sandpaper (220-ish).  Repeat for the second half.  Lay down the cloth, mix the epoxy, brush it on starting in the centre, put a coat on all the new cloth, let cure for at least 3-4 hours. Photo 70.
Step 6- cut off the excess cloth from the second half, lightly sand.
Step 7- add a second coat over everything and let cure 3-4 hours.  This coat is thinned 50-50 as well. This coat fills the weave. Photo 70.  Note the clamps in photo 73- a bit of cloth curled after the first coat (workmanship issue).  The clamps keep it flat while the glue from the second coat cures.
Step 8- add a third and final coat.  This coat adds the smooth surface.
Step 9- sand things smooth.  If it is a bit rough, add a 4th coat to fill in thin areas.

Paint.

Frank

[Frank v B]

Install the motor
- Found a Graupner geared Speed 400 (geared 2.33:1).  Made motor mounts out of ply and balsa and glued it to the hull.
To line up the motor and the shaft I slipped a piece of brass tubing over the two.  Once the glue dried, I removed the brass tube and installed the flexible coupling.

Note: it is always best to use some kind of gearing on a motor for a displacement hull*.  Direct drive is used in speed boats.

Frank

* a hull that does not rise out of the water as it speeds up.

[Frank v B]

Fibreglassing the hull- continued

- finished the 3 coats on the hull.  It used less than half the bottles of 15 minute epoxy.  A lot less than I thought it would take.  See photo of the bottles.

- a photo of the hull after 3 coats.  Letting it cure overnight.

Frank

[piker]

Hey Frank!

That's looking great, and coming along quickly (at least it seems to me)!

It's a cute fishing boat.  I like the style.

Robert

[Frank v B]

Thanks Rob.

Coating the deck with epoxy (no cloth) while the 3rd coat of epoxy is still curing on the hull. Photo 81

note in photo 82- clamps on the stern to hold loose cloth to the railing while the glue dries.

Frank

[msatin]

Looking beautiful Frank!

[Frank v B]

Thanks Mark.

Still puttering along:
- added a 4th coat of thinned epoxy.  It made a huge difference. Fully filling the weave of the cloth.
- sanded and filled the imperfections with spackling.  It was hard to see the imperfections.
- opted to spray paint the hull gray.  That drew complaints of odour in the house...even though the spray painting was done outside.
- sanded and filled the imperfections again.
- painted it with a coat of gray Tremclad rust paint--- because I had it.  This made the hull a uniform colour so the imperfections would show up better. It is curing now. It is also thicker than spray paint so that sanding will be more effective at filling holes/dents.

Photo 96 shows the white spackling filler on top of the sanded first coat of gray spray paint.

Frank