308jockey

Afternoon all,

This past weekend at the Perry GA model show I found a couple of boats I just couldn't leave behind, especially at the price I was able to get. The one I want to ask about here is a PT boat that I have no information about. It is 39 inches in length, a glass hull and deck with two plastic sections that open into the hull as shown in the photos. It has part of an electrical system in it that makes no sense to someone who runs mostly nitro boats. It has a pair of what I assume are ESC's. There is no writing on either and they appear to be wired for different battery types. The blue one has a pair of T or Deans connectors, I don't know the correct name, but I use these same connectors to plug Lipo batteries into my 400 and 450 class helis. The red ESC has older style connecters like I would have used for the six-cell nicad packs in older cars or boats. Both have a pair of nipples that I am guessing are for water cooling the unit though I've never heard of that type of cooling. Each ESC has a pair of connecters wired together. Each has a switch but the switches share a common wire. There is also a mess of speaker wire that runs to lighting throughout the boat. The hull has three prop shaft tunnels but appears to have only used two motors. There is an older 2-channel AM reciever and two servos, all of which will be replaced. It also came with a pair of Graupner electric motors with a geared unit and shaft with props. These appear to be '70's technology and not compatible with the electronics on the boat. The guy selling all of this had about 5 tables full of boats and helis. I suspect he bought this and was planning on doing something with it later but never did. It's obviously been run and the original motors removed. My first thought is just to pull all of the electrics out and start over, hopefully using the ESC's and finding new motors. I also suspect I'll take all of the crewmen off and re-paint. The crew appears to have come out of a bag full of plastic soldiers from a toy store that were hand painted. I like the concept and may replace them with something better detailed. The paint job took a lot of effort but I just don't like it. I'll probably research some PT boats and give this one a single number instead of the two it now has. My questions are: What kit is this? An ARF boat or was it built? Are those really ESC's or are they something different? If so, what would be the best battery and motor combination to use? It's set up for three motors but appears to have only ever used two. Will this boat need ballast? I have almost no experience with scale electric boats but look forward to re-floating this one and have a nice pond cruiser to go along with my Dad's old Dumas Tuna Clipper and the race boats we've been running. A calm evening, a cool beverage and a nicely lit scale boat chasing the ducks....that's the good life. Thanks for any light you can shed on this project.

Rick H.

308jockey

A few more photos.

Rick H.

Deathwish

My Feedback: (6)

Try this site out

http://www.pt-boat.com/

Deathwish

My Feedback: (6)

FOR RADIO CONTROL USE:
2 channel radio
6V electric motor DUMG2020
Running Hardware kit DUMB1362
6-cell battery
Battery Charger
Speed Control (can use DUMB2520)

Deathwish

My Feedback: (6)

btw pro boat made one thats 40" idk if it's the same one or not but you can give them a call

here's the one on there site.

http://www.proboatmodels.com/Product...ProdId=PRB3600

308jockey

That's the one Deathwish thanks!! This one has ben re painted and I don't know if I like it or not. Probably not. It's missing the motors but those are available. I now know that the red box is an ESC but there is no mention of the blue one. Apparently this has been modified somehow. Looks like I may just re-wire the whole thing. It has the light kit but that will need attention as well. New it's kind of pricey I think, I wonder how fast it is. Even with new motors I'll be into this one for under $100. Thanks for the information.

Rick H.

Hydro Junkie

Someone doesn't know anything about PT boats as they were never painted like that in combat areas. In the Solomons in 1942/3, when a new boat showed up with OD green and brown scheme, it was repainted grey and the large white bow numbers were not redone due to visibility issues. The boats survived by stealth and having huge white numbers on the bow would make the boats easy to see, even at night over a long distance. My advice is to strip the boat down, repaint it in a proper grey and lose all the army men. If you need to put a crew on board, make them more scale appropriate as what the person put on are way too small

Hydro Junkie

Someone doesn't know anything about PT boats as they were never painted like that in combat areas. In the Solomons in 1942/3, when a new boat showed up with OD green and brown scheme, it was repainted grey and the large white bow numbers were not redone due to visibility issues. The boats survived by stealth and having huge white numbers on the bow would make the boats easy to see, even at night over a long distance. My advice is to strip the boat down, repaint it in a proper grey and lose all the army men. If you need to put a crew on board, make them more scale appropriate as what the person put on are way too small

siberianhusky

You have a brushed esc there (red one) and a brushless esc from a Miss Geico cat (blue one). Very different in what they will run.
I'd personally get another brushed esc, if you can find a match, rip out all the wiring and start from scratch.
The motors are antique technology but good enough for a scale boat.
I'd stay away from the dumas crap, over priced and not very high quality at all.
Could probably run a pair of car esc's as well if they have cooling fans on the heat sinks. Should be a pretty low amp draw setup.
Nothing wrong with the graupner motors, be better than Dumas that's for sure. Not worth replacing all that stuff unless they don't work.
I think you just need a pair of matching brushed esc's, a Y harness to connect them both to the RX, and batteries.
Looks like a nice boat, just about everything there to make it run.
BTW you could get about 50$ for the blue esc used.
Please Do Not waste money on that dumas speed control, antique technology! For far less you can get a modern esc with many more options and better amperage ratings than that old 70's POS!
For about 5$ you can get a 20 amp brushed esc from HK, need a heat sink added but it would work.
http://www.hobbyking.com/hobbyking/s...USHED_ESC.html

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXE527
here is a link to the 55$ 1950's technology Dumas esc.
LOL which would you prefer.
Other slightly more expensive modern esc's for cars are another option, Crawler escs may be good, don't know, don't do rc cars.

308jockey

Holy jumpin' jiminy, that Dumas esc is the same one my Dad put in a Dumas Tuna Clipper back in the '70's! $55? Really? I like the Turnigy unit much better. Cheaper too. A pair of those with brushed motors and batteries will get this boat in the water economically. The crew figures are history and a good wet sanding is in the future. I'll do some research and paint it back as a scale paint scheme and make it a 109. I'm looking forward to some cruising with this boat later in the season. Thanks for all the information and I'll post photos as the project continues.

Rick H.

mfr02

A lot depends on the particular type of Graupner motors - they made a wide range of sizes, and quite a few variations for each size.  Gearboxes speak of displacement hulls like tugboats, a fast boat like a PT really needs direct drive.

Got RPM

Someone isn't as correct as they think they are. It all depended on where the boats were operating. These combat zone photos indicate that camo was used. Numbers, not so much...

Deathwish

My Feedback: (6)

pic one and 3 has the numbers near the top deck

tollytime

SERVICEBULLETINALERT!!

I purchased a ProBoat PT-109 "AS-IS"that was previously returned to a online hobby distributor. The boats electronics were tested and functioning at the time it was purchased. There was some broken parts on the deck, but nothing that couldn't be fixed. I dropped in the batteries and took her out on the pond for cruise. She got on plane and handled well for a boat her size. I stopped and noticed the stern was low in the water.

It was sinking!! Yep, she was goin down!! I hit the throttle and grounded her in a soft patch of weeds. After draining out the bildge, I didn't see any sign of holes. I brought her into my work shop, turned off the lights, and stuck a high powered LEDflashlight in the bilge. The flashlight revealed some careless mistakes madeby Chinese slave labor camp that built her. There was pinholes all around the stuffing tubes that were letting plenty of water in. Not enough epoxy to make a good seal.

I picked at the epoxy and it just flaked off all aroung the stuffing tube.

I'm pretty sure this is something you should check.

I plan on converting this boat to brushless this summer.

rblubaugh

My Feedback: (5)

Tollytime,

I'll be following this conversion.  Will you be making a speedboat out of her or a scale running PT boat with a little extra  speed built in?

Bob

308jockey

Tollytime I'll be watching with interest as well. If you get time I'd be interested in seeing more photos of how yours is done now inside the hull. Mine was a mess and had no motors and it was good to see how they had been done. I have no experience water cooling anything electric. I spent some time getting everything out and off of mine. I piled it all up just for fun. Those Army guys are definitely not period correct, most are carrying M-16's. Still, someone had a fun time customizing this boat and probably learned a lot along the way. I'm about ready to get out some wet sand paper and go to work. I won't take it all the way down but will get back to smooth paintable surfaces. I'm also going to look around for some web sites that can give me more information on PT boats and see what kind of a scale project this might become.

Rick H.

tollytime

I'm not converting my PT into a speed boat, but I do want better power.

Let's start with the info page. http://www.horizonhobby.com/products...e-_-PRB3600#t1

Many parts are still available. Click on "parts and accessories" and then click on "parts listings" on the lower side menu in grey.

Some parts listed as "Discontinued" may still be for sale on Ebay.

You may have to enter in some ofthe exactpart numbers on your Ebay search to find them.

Typing in "ProBoat Pt-109" on your Ebay search will bring a lot of items up to the surface.

Click on "manuals and support" and you will find a complete manual in PDFform when you scroll down. There are good pictures (with part numbers) that should answer all your questions

Here are some more pictures of the inside.

What's missing from the drivetrain?

(2) 550 motors: (PRB3105)

(1) SSDriveshaft kitwith motor couplers (PRB3605)

(1) Cooling system kit (PRB3607)

(1) Motor mounting Kit (PRB3608)

(!) Propeller kit (PRB3621)

I'm not sure ife you need new stuffing boxes or not.

308jockey

With winter still holding on tight I got out the water bucket and wet/dry sand paper and went to work. I didn't bother to go all the way to the surface as I wasn't worried about weight, I just got it smooth enough to make a nice paint surface. I then got out some Model Master flats that I already had and sprayed. I thought about going with grey but I already had this and have seen some PT boats in this color. I'll be doing a good bit of detail hand painting the next day or so and then I guess I'll start ordering some running gear. Hopefully it will be in the water in a week or two.

Rick H.

1sgt

Looks pretty cool the way it is. I can't wait to see wat you do with it.

Jim

308jockey

Tollytime thanks for the photos, they answered several questions. I had a couple of others though. What are you using for batteries? Based on the white plastic plugs on the ECU I am guessing a pair of 6 cell nicad packs like we used to run in cars. Do both motors run in the same direction or are they counterrotating? I need at least one prop or can just buy 2 new ones of some type. I also need a couple of coupling units of some kind to attach the shafts and motors. I am not using original motors but two matched units I already have. New motor mounts are not available but fabricating some should not be a real problem. Some one tried to drill a center shaft in this hull and made a mess of it but it will fix easily. Glad I checked that. Do you locate your batteries forward and do you use much ballast? A couple of parts and 2 or three evenings should have me in the water. I just wish the wind would quit blowing so much. I'm fresh out of sailboats and kites...


Rick H.

Hydro Junkie

Let me throw some some fuel into the fire. Here's info on the boat from the first picture:
Laid down 17 June 1943 by the Electric Boat Co., Elco Works, Bayonne, NJ
Launched 4 September 1943
Completed 16 October 1943
Placed in service 22 October 1943 and assigned to Motor Torpedo Boat Squadron TWENTY NINE (PTRon 29) under the command of Comdr. S. Stephen Daunis, USN
PTRon 29, assigned to the Mediterranean, based at Calvi, Corsica, and Leghorn, Italy, and had action along the northwest coast of Italy and southern coast of France, operating under the British Coastal Forces
"Hairless Joe" was transferred to the Soviet Union 7 April 1945 and reclassified TK-434
Fate unknown.
Specifications:


Displacement 56 t.
Length 80'
Beam 20' 8"
Draft 5'
Speed 41 kts.
Complement 17
Armament: One 40mm mount, two 20mm mounts, four 21" Torpedoes and two twin .50 cal. machine guns
Propulsion: Three 1,500shp Packard W-14 M2500 gasoline engines, three shafts.

As for picture 3, here's info on it as well:
Laid down 6 December 1944 by the Electric Boat Co., Elco Works, Bayonne, NJ
Launched 21 April 1945
Completed 10 May 1945, placed in service and assigned to Motor Torpedo Boat Squadron FORTY (PTRon 40) under the command of Lt. Comdr. George E. Cox, Jr., USNR
PTRon 40, assigned to the Pacific Fleet, arrived at Samar, Philippine Islands, in the summer of 1945, but had no action with the enemy prior to the cessation of hostilities
The "Hell Razor" was placed out of service 21 December 1945
Sold in May 1946
Fate unknown.
Specifications:


Displacement 56 t.
Length 80'
Beam 20' 8"
Draft 5'
Speed 41 kts.
Complement 17
Armament: One 37mm mount, one 40mm mount, one 20mm mount, two Mk 50 rocket launchers, four 21" torpedoes and two twin .50 cal. machine guns
Propulsion: Three 1,500shp Packard W-14 M2500 gasoline engines, three shafts.

That all being said, there is documented orders to repaint boats completely grey IN THE SOLOMONS to make them harder to see. In books about the boats serving in the Solomon Islands I have read, a camo boat was considered a liability. The boats were out in the center of the chanels between islands where camo would not be as effective . As for PTs in the Med, they were used differently as the environment was different. I do know they were used in conjunction with British F-lighters to combat the German steel hulled torpedo boats and may have used the camo to hide inshore until the German boats were sited but that is a guess as I'm not as studied in that theater. As for the last picture, it was taken just prior to Japan's surrender and would probably have been used close inshore to combat Japanese barges as there wasn't a larger target left, thus the camo would have been usable. The middle picture was an early 77ft Elco, PT-20 class. Could have been one of the boats sent to the Phillipeans with Ron 3 where hiding during the daylight hours would have made the camo helpful against Japanese aircraft and surface combatants as they had no real base to operate from after the first few days of the war. I saw a picture of the six boats on a tanker taking them to PI that shows them completely grey as well so it could have been something the crew did trying to survive. It is also possible that shot was taken in the South Pacific with Ron 3(2) in the Solomons or New Guinea , as some of the 77 footers were used in those areas until 1943 when many were pulled due to being obsolete.
If you want more info about the various boats, you can find it here:
http://www.navsource.org/archives/12/05idx.htm

tollytime

The motors both turn in the same direction (counter-clockwise) and thus use Left Handed propellers. The replacement props come in pairs (PBR3621). The Proboat (PRB3510) may be the single version, butI'm not sure. Plenty available on Ebay. I've heard they break easy and most people upgrade to metal props.

Converting it to counter-rotation will require a LH and RH prop. I'm not sure if the timing on the motors are the same when one of them is re-wired for reverse running. The real PT boats had props that turned in the same direction, Surprise!!

What type of propsshould you upgrade too? There are many solutions. I don't know how much you're willing to experiment.

http://www.cornwallmodelboats.co.uk/...ropellers.html

The 35mm M4 (4mm) threaded plastic props look like good replacements, but maybe you want better.

You have plenty of standard 3-blade 35mm M4 brass props from Raboesch and Rivabo.

Should you maybe opt for the 3-blade 35mm M4 "skewed" prop that is more suited for high speed patrol? The ProBoat plastic props do have a "skewed" look to them.

What about a 35mm M4 4-bladed propellers. They also come in a skewed version as well.

I would try the 3-blade 35mm M4 "Skewed" style. Part No: RAB160-04 (Left hand) You will need to order a Right hand and Left hand if you want counter-rotating.


For batteries, a pair of 7.2v 4200mAh Duratrax NiMH is what I use. Duratrax makes a 8.4v 4200mAh NiMH with 7 cells, for an extra boost in performance.

I have only used the factory battery trays near the rear of the boat since I've owned it. The battery trays are actually a part of the boats inner wood structure just in front of the rudder shafts. 7 cell battery packs will fit.


I have never tried ballast, but I haven't run it that much yet.


ProBoat seems to have run into a motor mount shortage. A PRB4211 should work just fine. You can find them on Ebay.

The is shaft coupler is 4mm on one end and 1/8" (3.175mm)on the other. You have an M4 shaft (4mm) and the motor is 1/8" (3.175mm). You have to buy the shaft kit to get them (PRB3605)










<actinicrices prod_ref="RAB160-04" retail_price_prompt="Price:">
</actinicrices>

308jockey

Someone mentioned to me the idea of counter rotating props as a possibility but since neither the model or the full size normally run that way I won't make that change. I have nearly everything I need. I found a matched pair of motors I didn't know I had and purchased a cooling system that fits perfectly. I have ordered props and universal joints. Couldn't find motor mounts after a short search so rather than continue looking I got out some sheet aluminum and made some. My sheet metal skills are only fair and they are not pretty but they work. I doubt I'll see the remaining parts this week but there isn't much left to get this one afloat, maybe 6 hours of work. I'm also contemplating a lighting system that will provide some exterior lighting and a little bit on the inside as well. I know this wasn't used in combat but I've made sure my local pond has been cleared of any Axis combatants and it will be safe cruising. I'll get some more photos posted soon. Tolly and HJ, thanks for all of the information.

Rick H.

308jockey

It runs! I had to wait on a few parts, the couplings from engine to drive shaft were unavailable so we found some others that worked. I took the motors that were sold to me with the boat and removed them from the gearboxes, brushed motors very similar to the originals. It took less time to form some sheet metal into motor mounts than to search the web and order them and although I'm not much of a sheet metal mechanic and they aren't pretty, they work. I also had to sleeve the output shafts to fit the couplings from the motor but again a simple matter. I put new factory props on it. Before I put it in the pond I floated it in my bathtub. It sat well but was leaking from the back. I had already plugged the hole a previous owner had drilled for a center prop shaft and suspected a leak around a skeg and painted resin around all three to be sure. Then on to the pond.

It looked good sitting still in some calm water. The winds had died following a storm yesterday. Nothing to do but push the throttle forward and it really took off! I tested steering and throttle response and was pleased. High speed runs look to be around 12 to maybe 15 mph. I think the nose was a little high at speed and will ballast the front before running it again. I brought it in after about 10 minutes and found it was still taking on water. Dumped it out and saw nothing obvious but I'll inspect it more closely. Put it back in the water as the batteries weren't anywhere near exhausted. I was dodging a couple of floating branches when the boat clearly struck something at speed, either a fish or my dad thinks a snake. Whatever it was was undisturbed and I saw it continue to swim close to the surface for several more minutes. Anyway it lost a lot of speed so I brought it back in to find one of the props missing! Damn! It hadn't unscrewed but the plastic had separated from the metal inner sleeve that threades on to the shaft. New ones are on the way. Also you may notice in one of the photos an aft torpedo tube came loose from it's front mount and is dragging which occured in the collision.

As always I discovered a few problems. There is a poor solder joint to one motor terminal which will have to be re-done. The balance problem should not be difficult. I did notice that the cooling system was not working. I didn't expect a large jet of water that I see in our gas and nitro boats but there was nothing at all. Checked the motors and ESC, all were quite warm but not hot. I could probably leave it alone but since I went to the trouble and expense of installing it I want it to function. And I have to sort out the leak problem. I always expect a little leakage but this is too big to just ignore. Besides, until the new props get here what else have I got to do? I'm very pleased with this project. It was pretty rough when I found it. These boats were orginally selling for over $400 apparently but I'm into it for a $50 purchase price plus maybe another $75 in parts. That includes a motor I bought but didn't use. There is maybe 20 hours of work in it, probably less. Now that it's been tested I'll also install a light kit and put appropriate insignia and a flag. I'll do something to make the antenna less noticable also. And I still have those painted-blue plastic army men if anyone needs them :-). So where is a scale boat club to be found in Central Alabama?

Rick H.

dauntlessfan

Rick that PT looks great on the water, nice work!