Source for driveline parts for ~15" PT-109 - RC Groups
Shop our Airplanes Products Drone Products Sales
Thread Tools
Jul 31, 2017, 10:48 AM
Registered User
wparsons's Avatar
Discussion

Source for driveline parts for ~15" PT-109


I've been looking for a complete 1/64th scale Lindberg RC kit, but haven't had much luck (just missed one on eBay...). Does anyone have any suggestions for what size motor/esc I'd need (brushed or brushless is fine) for it, as well as where to get a suitable propeller? The boat is about 15", and the original RC kit used a standard size servo stripped down as the motor/esc, run off 4 alkaline AA's.

Any help would be awesome!
Sign up now
to remove ads between posts
Aug 01, 2017, 01:50 PM
Webmaster, MMCNE
RCBoater's Avatar
You can find little prop/shaft/tube assemblies in the offerings of both Cornwall Model Boats and the Model Dockyard.
For a universal joint, you can use a tube, such as the insulation from a piece of wire. A better option is to use model RR HO universal joints. Northwest ShortLine carriies them-- nifty little ball and socket unversals for use on small diameter shafts and motors.

For motors, I can't help as much-- I don't have any experience with go-fast micro boats. I can say that motor choice depends on what you're after. The original Lindberg kit used a converted servo, the same as found in their motorized Diesel Tug. I've got one, and it does a fine job in the tug-- but I doubt it would get the PT up and planing, if that's your goal. But a servo-sized powerplant would do fine if you just want to cruise around at "harbor speed".

If you are ion the market for such a powerplant- take a look at the continuous rotation servos offered by various robotics suppliers. They come with the feedback pot loop already disabled- so that they are essentially little ESCs and motors in one unit Take it apart and use the motor on direct drive for a boat.
Aug 01, 2017, 02:11 PM
Big Boats Rule!
boater_dave's Avatar
Lots of hardware around for 1:18 & 1:24 scale rc cars & trucks. Most are 6-7 cell nixx, or 2 S lipo. Plenty fast for the little Lindy PT. I used the electronics, but tamed down the motor for use in my USCG cutter which is not a go fast type.

Dave
Aug 01, 2017, 02:51 PM
Registered User
wparsons's Avatar
Thanks for the input guys! I had one about 20 years ago and it definitely didn't get up to anything approaching on plane, but moved around ok with the converted servo.

I've been looking at some micro outrunners since I'd like to use some of my existing lipo batteries in it and the brushless ESC's already have a cutoff in them.

The original used much heavier gear, I'm sure I can build it way lighter and then add ballast as needed.
Aug 01, 2017, 03:00 PM
Just Plane Nutts
AirDOGGe's Avatar
Be cautious with outrunners, as they induce a lot of roll motion with throttle position changes.


One plan might be to obtain a 13" long $35 Fei Lun FT007 and strip the works out of it for use with this boat. Radio too.
Aug 01, 2017, 04:25 PM
Registered User
wparsons's Avatar
That's not a bad idea other! The outrunners I'm looking at are in the 18mm diameter range, and quite light, but it might be enough for a small boat to roll more than desired.
Aug 01, 2017, 05:08 PM
GJB
GJB
Registered User
Hi,

I have been building an Airfix S100 of simular size. I went for the cheap way and just put in 2 130 SH motors in series.
Props are 3 blade 12mm from shapeways. https://www.shapeways.com/product/9H...ionId=40860193

Axles 1mm, stuffing box 2mm.

Speed goes from slow to scale to lunatic Powered by a 2 cel 1000mah lipo and single cheap esc.

Brushless is nice but not needed in this scale. Keep it simple and cheap

Regards,

Gert-Jan
Aug 01, 2017, 05:51 PM
Just Plane Nutts
AirDOGGe's Avatar
Quote:
Originally Posted by GJB
Hi,

I have been building an Airfix S100 of simular size. I went for the cheap way and just put in 2 130 SH motors in series.
Props are 3 blade 12mm from shapeways. https://www.shapeways.com/product/9H...ionId=40860193

Axles 1mm, stuffing box 2mm.

Speed goes from slow to scale to lunatic Powered by a 2 cel 1000mah lipo and single cheap esc.

Brushless is nice but not needed in this scale. Keep it simple and cheap

Regards,

Gert-Jan




Very nice work there.
Aug 02, 2017, 10:45 AM
Registered User
wparsons's Avatar
Quote:
Originally Posted by GJB
Hi,

I have been building an Airfix S100 of simular size. I went for the cheap way and just put in 2 130 SH motors in series.
Props are 3 blade 12mm from shapeways. https://www.shapeways.com/product/9H...ionId=40860193

Axles 1mm, stuffing box 2mm.

Speed goes from slow to scale to lunatic Powered by a 2 cel 1000mah lipo and single cheap esc.

Brushless is nice but not needed in this scale. Keep it simple and cheap

Regards,

Gert-Jan
Do you think a single lower rpm 130 motor with a plastic 1" (25mm) prop would work? I was looking at this motor:

http://www.ebay.ca/itm/DC-12V-18000R...QAAOSwZQRYbQXG

and this prop:

http://www.dumasproducts.com/product...roducts_id=526

alternatively, this is one of the outrunners I was looking at:

https://hobbyking.com/en_us/turnigy-...or-1800kv.html

If the brushed 130 will work, it's a simpler option and I can go through 10 of them before hitting the same cost as the brushless one. I plan to run a much bigger battery than it actually needs since I have them and it'll likely need ballast anyway. I have both 2s and 3s packs so I'll have options for speed as well.
Last edited by wparsons; Aug 02, 2017 at 10:51 AM.
Aug 02, 2017, 11:23 AM
Registered User
The last thing you want in a performance boat is ballast unless you have stability problems. The brushed 130 sounds good, but will need plenty of volts - 3S Lipo or a lot of NiMH. In a small model, the batteries are a significant part of the total and positioning is crucial to getting the trim right. Ballast that has no other job is a last resort.
Aug 02, 2017, 01:35 PM
GJB
GJB
Registered User
Quote:
Originally Posted by wparsons
Do you think a single lower rpm 130 motor with a plastic 1" (25mm) prop would work? I was looking at this motor:

http://www.ebay.ca/itm/DC-12V-18000R...QAAOSwZQRYbQXG

and this prop:

http://www.dumasproducts.com/product...roducts_id=526

alternatively, this is one of the outrunners I was looking at:

https://hobbyking.com/en_us/turnigy-...or-1800kv.html

If the brushed 130 will work, it's a simpler option and I can go through 10 of them before hitting the same cost as the brushless one. I plan to run a much bigger battery than it actually needs since I have them and it'll likely need ballast anyway. I have both 2s and 3s packs so I'll have options for speed as well.
The fast 130 option is for max 13mm props. 25mm would be to much. How big are the kit props? Normaly I use the kit props as a reference.

If you go for a singe setup a 380 should have enough power for the 25mm prop.
Last edited by GJB; Aug 02, 2017 at 01:40 PM.
Aug 02, 2017, 05:14 PM
Registered User
wparsons's Avatar
The 130 motor I'm looking at is 1500kv, so I'd be at ~11k rpm on 2s and ~16k rpm on 3s. I'm not looking for a fast boat, it's a scale boat first. I think a 380 would be way too much motor in a ~15" PT-109. The original kit used a standard servo without gears to directly spin the prop, which is definitely less powerful than a 130 motor? My rough logic was to cut the rpm by about half compared to the motor you're using to allow the bigger prop to work. I'm open to other suggestions as well, but I'm struggling to find reasonably priced props outside of the 1" one.

I had a 16" hydro with a 20mm brushless motor and 32mm prop that ran in the high 20mph-low 30mph range, definitely not looking for that much power or speed.

The ballast would be to keep the boat low enough in the water at rest. The kit was designed for a standard servo for steering, 4 AA cells for battery power, standard size RX, and stripped down standard servo for power. I'm looking at using a ~5g receiver (have one handy), 9g servo (also have it handy), ~800-1000mah lipo packs (have them handy too).

Here's a video of an unboxing to give an idea of size:

1:64 Lindberg JFK's PT-109 (8 min 12 sec)
Last edited by wparsons; Aug 02, 2017 at 06:33 PM.
Aug 02, 2017, 09:56 PM
Registered User
wparsons's Avatar
Found a couple more options...

motor: http://www.ebay.ca/itm/DC-3-7V-7-2V-...MAAOSwpAZZcHR2

prop: http://www.ebay.ca/itm/Original-Feil...QAAOSwY0lXR96l
Aug 02, 2017, 11:14 PM
Just Plane Nutts
AirDOGGe's Avatar
Some parts in this learning kit that look useful (motors, metal mounts, shafts, motor-to-shaft couplers, etc....)

http://www.ebay.ca/itm/12-7-5cm-Boat...kAAOSwud1W~hi2



Or, instead of using a 13" FT007 with a 370 motor for parts, you could use this 9" Volantex Vector28 (10.8" including rudder) with a more appropriate 180 motor: http://www.ebay.com/itm/Volantex-Vec...IAAOSwzqFY9XtY




Last edited by AirDOGGe; Aug 02, 2017 at 11:44 PM.
Aug 03, 2017, 03:46 PM
Registered User
wparsons's Avatar
That's a bit expensive just for the couple parts I need, but a great idea if I needed more than just motor and prop.


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Electronics for Lindberg PT 109 kaherc130 Scale Boats 1 Jul 30, 2016 04:22 AM
Help! electrical parts for Lindberg PT 109 scale 1/32 rabosr Racing Boats - Electric 3 Jun 25, 2014 04:51 AM
Help! Dumas PT-109 Vacuum Parts Larry_thE_Deer Scale Boats 2 Jun 25, 2010 02:39 PM
Discussion imex PT 109 vs proboat(old midwest)PT 109 aslvrfrostcsvt Scale Boats 15 May 22, 2008 11:32 PM
Discussion Lindberg PT 109 conversion part 1,2,3,4,5 norgale Scale Boats 74 Mar 11, 2008 12:13 AM