Revell 1/72 scale plastic Flower Class Corvette- repair/rebuild..yes, an RC boat

[Frank v B]

Got this from Greg.  It followed him home but he was conflicted.  Re-building it to his standard would kill him, so he asked if I would fix it to my (lower) standard because he did not have the heart to throw it out.  It was pretty well trashed.

Approach:
1) put the Shelley Foss tug aside after tomorrow until I can paint it outside in warmer weather.  Will finish the RC installation tomorrow.
2) spend one week on this Corvette project to see if it is indeed salvageable.
3) after one week- start working on my airplanes again in anticipation of an elusive seasonal concept called "spring".  Have 3 airplane projects to get ready for MaidenFest (.46 size Mustang, 2.4 meter power glider, 12' span power glider).  Also a special project- build a project with Mark because it lacks proper instructions.  Mark will post this one later.

Repair approach for this Corvette
- have taken the motor out. It was a brushless 2836- 3300 KV motor.  So wrong. That is a ducted fan motor.  It would make this thing do a tail stand (stern stand?).
BTW- boats need about 15 watts per pound to power a displacement hull.  Will probably switch to a geared, brushed motor- speed 400 type. (80 watts).
- taken the decks off and rudder out (too big)
- repair 2 broken hull cross braces and re-inforce the other four by sistering balsa to them to stiffen them.
- install the gear train and rc equipment.  Make everything accessible through the removable back half superstructure.
- figure out how to fake the broken detail stuff (guns, depth charges, railings, guy wires)  will be applying the boat version of the 50/50 rule.  If you can't see it at 50 feet and 50 feet per minute, don't waste your time on it.

Shocks
1) The last time I bought a tube of Testors plastic cement when I was a teenager, it cost 49 cents.  The same tube is now $5.00!!  Either inflation is incredible or I'm very old.
No comment Andy.
2) Just Googled the motor that came with the boat- it is for a 64mm ducted fan using a 40 amp ESC 4 cells... about 500 watts.  This boat could literally fly with it.  Beyond soooo wrong.

Frank

[Frank v B]

repairing the braces: re-glue the plastic ones supplied by the kit, then doubling them up with 1/4" square hard balsa to stop the flexing.
These braces hold up the deck and stop the hull from flexing.

Frank

[GuyOReilly]

Looking forward to seeing it at Toogood Pond when the water softens.
Go TEMAC (Toogood Electric Model Aquatic Club)

[Frank v B]

The re-build:
i) The braces are in place.  Cannot install the two missing ones until I know how wide they need to be.  The hull flexes.  Plan to install the decks (3 pieces) as I go along.  The first deck (bow) is ready to go.
ii) All the guts (drive train, RC equipment) need to be installed permanently before the decks can be installed and lock it in.

Step 1- Fibreglass the center joint.  There appear to be gaps. There is epoxy slobbered all over the hull and it peels off...much like Simon's sanding of the PT 109 hull. Peeled off the glue that was not sticking.  Note: plastic models parts can have mould release on it from the manufacturing process.  Glue may not stick until it is sanded first.  Sanded the joint/bottom of the hull will 400 sandpaper until dull.

Step 2- Use the watery epoxy (5 min) brushing of fibreglass trick.  Thinned it by mixing in about 40% alcohol and brushed the glass in place.  easy.  I did not test a spot whether the liquid  eats the plastic hull.  Then I just have to say "sorry" to Cadez and my problem/challenge is solved... a ball of melted plastic.

Step 3- Secured the shaft- the shaft was wobbly because it was un-supported.  Cut a piece of 3/16" balsa to fit between the shaft and the hull, then glassed it in place with 5 minute epoxy and waxed paper. Photo 84.

Letting it cure over lunch.

Frank

[Frank v B]

FYI- just measured it.  34" long.

[Frank v B]

..after lunch... The hull did not melt from the epoxy/alcohol mix.  Quite strong and the seam at the keel is sealed.  Best to keep all water in the lake, not inside the boat.

Installed the motor
- used a geared 300-ish motor from an airplane that had a brush-ectomy.The prop is on the large side so the motor has to be geared.  It does not need much power to push this light-weight boat.
- used a piece of silicone fuel tubing for the coupling from the motor to the shaft.  Flexible enough to work through small mis-alignment issues.
- this was a GWS-type stick motor mount.  Attached it to a balsa cross-brace.

Frank

[Frank v B]

Installed the foredeck but tried to adhere the paper wood deck detail.  Several areas were loose.  Squeezed wood glue under it with a toothpick.  Purpose- the moisture in the glue relaxed the paper so it would lay flat.

Clamped the end closest to the edge.  The piece of balsa spread the load so the deck paper would lay flat while it dried.

Trick- tried to find a way to squeeze the paper flat nearer the bow where clamps could not reach while the glue dried.  Used 8 round rare earth magnets.  One under the deck and one on top.  Worked like a charm.

The photo shows the 4 shiny magnets (red lines) held firm by 4 magnets underneath the deck.

Frank

[Frank v B]

Ready for the spring thaw.

This is as finished as it is going to get.

These photos show:
- all the pieces in their place.  Pieces that were missing were built out of balsa and painted (base of the smoke stack, railings on the upper bridge, etc).
- cut all the guy wires because they were poorly rigged, broken.  Made it look messy.
- the back portion of the cabin comes off.  The smoke stack is removable.  Held in place by 2 sets of magnets.

The only thing left is to hook up the RX and battery and proper ballasting which can only be done in the water.

Looks better than expected.  Still a stand-waaayyy-off model.

Next project will be a plane.  I promise.

Frank

[sihinch]

Looks amazing Frank! WOW. And hopefully now sea worthy.

[msatin]

Looks Great Frank!

[Frank v B]

Today was the maiden voyage and it went well.  Not a drop of water inside.  The hull is 6 sections glued together plus potential leaks from the prop shaft and rudder post.  Half throttle was about scale full speed.  At full throttle the bow would lift out of the water and the boat would plane.  Not quite scale but.... .  No rooster tail.

Photo report:
79- Andy holding the boat just before the maiden launch.
80- at 1/4 throttle.
83- after the maiden voyage.

Neat project.  Thanks Cadez.

Frank

[Frank v B]

Trying to balance the boat fore and aft.  It needed weight in the bow to get it down closer to the waterline.  To get it there and secure it I made a moveable weight stick.  Glued and bound lead weights onto a plywood stick and put velcro on the bottom of the stick.  The other velcro part went into the hull.

The stick was pushed into the hull bottom and can be slid back and forth to find the right balance point.

Frank

potos:
- 75- top view
- 78- side view.

[sihinch]

Congrats Frank! It looks beautiful.

Sorry I missed it.