I know this will not fly but.......
Bought* this kit on RcCanada last year. It is both a project during my recovery from knee replacement surgery a month ago and...no RPAS needed. ;)
This is the way it arrived. Poorly built but very salvageable. A good thing they did not go further. All glue joints can be checked, fixed and the complete inside waterproofed. First time I have seen a wooden model built with hot melt glue. ::)
Plans:
- was going to go twin shaft but Mike Brodey was kind enough to give me a Decaperm- a very powerful geared 6 volt boat motor so will go single shaft/prop.
- will probably add the Kort Nozzle- a round tube around the prop that turns to steer the boat. It does not use a rudder. Akin to thrust vectoring in an RC leaf blower (jet).
- waterproof the inside
- fibreglass the outside
- colours will be traditional black hull, red below the waterline, white water line stripe and white doghouse (wheel house).
Purpose
Someone needs to tow Guy's broken down sailboats and fishing boat at TooGood pond.
May as well be me. Modelling's equivalent of RansomWare. ;)
There will be several progress posts but not too many because we are a flying club.
Note: I had one of these tugs before and was given to me. It was finished but no prop shaft installed. I painted it, added a Kort Nozzle, added a prop shaft and an Astro Geared 25 on 6 volts. Very powerful. It could plane in our back yard pool. Not quite scale. Sold it to Piker because he said "I ways wanted an RC model tug".
Frank
*thank you Oscar, my enabler.
Here is what a Kort Nozzle looks like on full size tugs.
F.
Quote from: Frank v B on December 13, 2023, 09:52:33 PM
Purpose
Someone needs to tow Guy's broken down sailboats and fishing boat at TooGood pond.
May as well be me. Modelling's equivalent of RansomWare. ;)
Well
@Frank v B you definitely will need a tug to pull that sub of yours after the depth charges have hit!!
PS: Looks like we should trademark the TEMAC subsidiary (i.e., the Toronto Electric Model Aquatic Club).
quick update:
- epoxied the inside- thinned it with alcohol, then hit it with a heat gun to make it flow into crevices.
- installed the shaft, rudder and motor. It was hard to get the angle right. Motor donated by Mike Brodey...to a good cause.
- installed the deck and built the first level of the cabin.
- getting to the frustrating parts... pieces are missing and the drawings do not allow parts to be drawn by measurement. Will have to fake it.
Note: the gap visible between the hull and the deck will be covered by the bulwarks (solid railing above the deck).
Frank
Bare bones of the wheelhouse and removable deckhouse taking shape.
The smoke stack is in place.
Next- filling and fibreglassing the hull.
Fibreglassed half the hull following the video instructions*. That was easy!
Equal parts of epoxy resin (20 min.), hardner and alcohol. The consistency was of water and it brushed out beautifully.
Note the excess cloth sticking out below the upside down hull. Once the epoxy is hard it will be cut off with an X-Acto knife.
Letting it harden for a few hours then will do the other half.
UPDATE- just did the second half of the hull. Total elapsed time including prep, glassing and clean-up was 20 minutes.
Frank
ps: the epoxy was the stuff I bought from the Eric Adams estate. Thank you Eric!
*Video on a separate post https://temac.ca/smf/index.php?topic=8898.0
Hey Frank,
This is super helpful, thank you! Question for you, should you install the motor and prop tube (not sure of the terminology yet!) before glassing?
Thanks!
S
Simon,
re: motor and prop tube sequence:
I would install the prop shaft and motor before glassing for 3 reasons
i) Lining up the shaft angle: most frame-built hulls use a keel. This tug had one about 1/4" thick (first photo). It is tough to line it up properly so the shaft is as much in line with the motor as possible. In this case I made the hole much larger than the diameter of the shaft so there was no binding. I installed the shaft so it floated in the hole, then back-filled it. Note the angle corrections on the keel outside the hole in the 2nd photo (white triangle- balsa filler).
2) Collateral damage: using drills and making holes larger than the shaft can cause a lot of damage.
3) Separate "building" from "finishing": fixing damage during the building phase is easy. It gets progressively more involved as you get closer to the finishing stage.
If the boat does not use a keel (few do) you can do it any time. This is usually only in completely moulded fibreglass hulls.
It's personal. I never like going backwards or fixing things twice.
Frank
Hey Frank, how heavy/thick was the fiberglass that you used? 2oz cloth?
Simon,
.68 oz cloth. Can be bought at Plastic World (Just west of A&J Hobbies https://plasticworld.ca/product/fiberglass-cloth-regualr-e-glass/). Mark Satin bought some last week at some ridiculously low price ($6.00 per meter).
For your PT109, like my Shelly Foss, the hull is planked with plywood so the fibreglass is used as a smooth waterproof finish. It would be different if it were sheeted with balsa where strength would have to be added via heavier cloth.
Frank
Thanks Frank!
Now show us more building! ;D
Simon,
The update:
- installed the bulwarks (railings above the deck). A mess!
- painted the deck, installed the windows, roof, painted the inside of the wheel house black, painted the entire superstructure.
- made the deck winch- put tow line onto the reel by attaching it to a drill and winding it up. About 20' of tow line.
Simon, I included the photos of the Dremel Multi- Max tool for sanding the fibreglass. Absolutely brilliant. The rubber pad contours it enough not to sand flat spots and never sanded through the cloth. Borrow mine when you go to glass your PT boat. It took less than an hour to do the entire hull (twice the area of your boat). Drips come right off and it is easy to see low and high spots because of the sheen (dull is high, shiny is low). Because of the triangular shape you can get into corners and tight spots.
Frank
ps: the weight of paint is not an issue because it is a boat. Used Benjamin Moore semi-gloss white trim house paint for the superstructure. Used Tremclad Grey rust paint for the decks... because I had them. A good latex paint becomes scrubbable after 30 days so it will be waterproof once the water gets soft in the spring.
Will spray the fibreglass hull (black and red) when it is a lot closer to the finish line.
Hi Frank. Your boat looks beautiful!
Any concerns about water migrating through microscopic voids in the latex and sitting between the latex and glass and possibly migrating into the wood through possible small holes in the glass?
No. ;)
Frank
ps: Half ounce cloth (woven like this or mat-type Angel Veil with random fibre orientation) was used as a first layer in a mould by full size yacht builders as a barrier to moisture migration (osmosis) into the heavier cloth with greater chance for voids. The latex house paint is used above the waterline.
Next Challenge (self-inflicted):
Add a bow thruster...without buying one.
Problem- to leave a dock:
- the bow needs to be pushed away from the dock before the rudder can take hold. You cannot leave a dock just by adding forward thrust and deflecting the rudder. The stern will hit the dock. Unavoidable.
- A boat with a single screw will kick the stern over when reversing/slowing down. It helps when docking with the dock on the left side but not the right.
Am cobbling a bow thruster together using:
- a small $5.00 surplus 5 volt DC pump from Princess Auto. Bought it 4 years ago in anticipation. Sure. ;D
- a standard servo (got lots)
- a brushed motor ESC (got lots)
- flexible fuel tubing.
Will show photos...if it works. ;)
Frank
ps: There is a factory-made bow thruster from Graupner. A proper thruster has a tube across the hull near the bow that goes through both sides of the hull. There is an impeller inside the tube. It was about $50.00, the price of a new airplane. This approach uses a stream of water to push the bow over. The ESC gives it variable thrust and the servo determines which side of the bow is pushed over.... in theory.
Bow thruster- back to the drawing board. Arghh!
here is the set-up for the bow thruster.
This board stands up in the bow. The servo links to both mouse trap pinch-off loops to select left or right. A bit like the control line combat fuel cut-offs.
Tested the pump. Two problems:
i) it seems to be weak on 4.8 volts unless on 6 volts. It clearly says "5 volts" on the label. I can always hide behind the fact a man never reads instructions and use 6 volts. If it burns out I will have to go back to the drawing board.
ii) It appears it is not self-priming- that makes it tough because the water has to be brought up 4" before it hits the pump*. May have to talk to Temac's pump expert- Pool Paul. Will try to source a windshield washer pump but it will need a separate 12 volt battery source. Not a problem but the boat is powered by a 6 volt lead acid battery.
Back to the drawing board.
Frank
* am trying to keep all joints above the waterline so if it fails it will not sink the boat.
Final prep before painting:
- glued in the rudder post. The tube sits about 3/16" proud of the hull surface (photo 50, right side of photo) so the rudder does not touch the hull.
- shorthened the prop shaft housing once the rudder was in place so I could accurately place the prop in front of the rudder.
- added the prop shaft strut at the bottom of the hull. Hard balsa, shaped it and epoxied it in place (photo 50). Wrapped two threads of Kevlar* over it and onto the hull to strengthen it (Photo 51). Added waxed paper and squeezed everything smooth (photo 52).
- added masking tape on the deck to start getting it ready for spray paint. The hull will be black, the deck is grey.
Frank
* Kevlar is the gold coloured thread. I use it because I have it. You can use unwaxed dental floss. It is amazingly strong in this application.
Building is pretty well done.
- sanded the hull's fibreglass covering smooth. Wow! Never for a minute thought it would be this easy or this smooth.
- installed the motor, prop shaft and prop in place so everything fits. The prop does not hit the hull!
- installed the rudder servo and rudder. It fits.
- added the battery tray and fit the speed control (an RC car one with reverse).
Added the masking tape on the deck- ready for spray painting the hull.
Only problem- cannot spray inside the house. I do it on the driveway but not while ice cubes litter it. ;)
Frank
Last day of the Shelley Foss build until painting it
- installed the ESC on the side of the hull. Two reasons: i) water always collects in the bilge (bottom), ii) this boat requires lead to bring it to the waterline. It is best in the middle (balance) and as low down as possible to reduce rolling in waves.
- installed the on/off switches for the radio and bow thruster. Purpose- so the boat can be assembled in the car and powered up when in the water. This boat will probably weigh in the neighbourhood of 15 plus pounds. My back!!
- wanted the access to the switches through the deck. Cut a hole below the deck winch, installed the switches and built a raised coaming around the hole. It is a lip to stop water running over the deck and into the hole.
Frank
Hey Frank!
I DO still have the beautiful tug you sold me (Did I even pay you for it?). I will get it dusted off and out to Toogood next summer!
Robert
Robert,
Yes you paid for it. It was $100.00.
I had to buy this replacement kit for $80.00, plus build it, plus power it.
You got such a deal*.
I remember you saying during the hand-over "I always wanted a tug".
Frank
* it was given to me (built, no shaft, no rudder, no motor, no servo) so the $100 covered the money I put into it.
Hey
@Frank v B ,
What's the latest on your windshield washer pump bow thruster?
Is it the same design as your pool pump plumbing loss of containment?!!!
Andy
How to paint a proper waterline: A hull has compound curves so nothing is straight in order to paint a waterline. On this project the top of the hull will be black. Below the waterline will be red....because it has to be.
To paint the waterline:
step 1: transcribe the waterline from the plans to the bow and the very stern. It is measured up or down from a fixed point. The waterline at the stern was measured from the bottom of the hull which was a corner so very reliable. The bow was measured from the chine.
step 2: set the hull on a flat surface and position it so the bow and stern marks are an equal distance from the top of the table. Now the fore and aft marks are set.
step 3: set the hull level (left to right) until the left and right sides are exactly the same distance from the table top. Note: I could not use a spirit level to measure "level" because the railings are not an equal height above the deck (not my fault. Ask the original builder).
step 4: clamp an ink marker in a holder and run it from bow to stern and around the other side. It worked surprisingly well. I used a solder clamp stand to hold the pen in the correct position.
A lot easier than I thought.
Now mask this line to paint the hull.
photo 1- (89) the hull sitting flat and level on a smooth table top.
photo 2- (87) marking pen in the holding clamp (solder clamps). At the bow mark.
photo 3- (88) line at the stern.
Frank
The hull masked off and finished with two coats of red below the waterline.
It was sprayed with a rattle can of red rust paint.
Spray painting done outside...otherwise that is where I would be living if I painted the hull inside the house.
Frank
Nice!
Finished painting the hull.
I will leave all the details now until some cold snowy winter day.
Used rattle can spray paints. The results were much better than expected.
The white stripe at the waterline is some trim tape I had lying around. Canadian Tire car trim tape.
It is now ready to run.
Frank
Beautiful!!