What size Motors? - Trying to decide on best motors for Gato

[mermaid]

What sized motors would be best for a 1/48 scale Gato? (a) If direct drive? (b) If speed reduced? For a speed reduced (belt) setup, I'm tempted to go with Graupner Speed 600 12V BB (ball bearing) units.
Would that be too much power? Could I get away with a 400 or 540? Sure, I would like good long run times, but I'd prefer to have ample reserve power for a bit of hotdogging and emergencies! I'm planning power the sub with an 8Ah gel-cell 6 or 12V power pack.

[tom dougherty]

Diane, How is your 1/120

Diane, How is your 1/120 scale Los Angeles class project progressing? What did you decide to do about representing the tiles? I believe you were thinking of attaching them individually?

I was also surprised that you are building a 1/48 scale fleet boat, as I recall that you wanted to do the LA in smaller scale due to space restrictions in your apt.

[mermaid]

Well Tom, a number of

Well Tom, a number of things have happened. I'm in the middle of building a super detailed 1/72 Type VIIC (Probably U-592). I haven't forgotten about the 1/120 scale Newport News. The problem is that I simply don't have the facilities yet to scratch build the hull the way I'd like. Once the U-Boat is done, I'd like to get my "feet wet" and build an RC project. I will probably be working on the Nuke and Gato simultaneously. There is a HUGE difference between a static scale and RC model. Static scale sits on the shelf and looks pretty. An RC boat DOES SOMETHING. I'll force myself to make room!!



Edited By Mermaid on 1142200604

[JWLaRue]

I'm in the middle of

I'm in the middle of building a super detailed 1/72 Type VIIC (Probably U-592).

Let's see some photos!

-Jeff

[mermaid]

Fact is, Although I have

Fact is, Although I have the Type VIIC kit and a bunch of detail goodies, I'm still waiting for the rest of my order from Mickster. Plus, Im waiting on tools and materials from Micro Mark. On top of that, I have to wait for documentation that I ordered today from Germany! Not much to photograph yet. However, it will all come together "in the fullness of time"



Edited By Mermaid on 1142216579

[Guest]

Hmmm, 1/48th scale Gato....big boat.

I'd

Hmmm, 1/48th scale Gato....big boat.

I'd go to the local motor breakers and look for european cars (i.e. VW, Audi etc.)

Find two of the same models, and pull the motors used for the heater blowers.

These are excellent low revving, high torque motors, and will easily turn the props on your Gato direct drive.

It'll work out a fraction of the cost of the graupner units (I pay about £3-4 for a motor, you can probably get them for less).

Andy



Edited By Sub culture on 1142274062

[mermaid]

Thanks Andy. Fact is, that

Thanks Andy. Fact is, that although the boat is long @ 78" It's really not that big in terms of volume and displacement. Scaled to 1/48, surfaced displacement is only 36.7 lb. (That would be a dry hull.) A wet hull model would be a lot less. Furthermore, the boat is long and slender with a max beam of only 6.8125". (The WTC is a lot smaller.) Sort of like a canoe. Consequently, there is not all that much space to play around in. I've explored automotive sources before and found that more often than not, the motors are simply too large for a model. A good source for inexpensive motors is "Country Cloth and Hobby" Don't know if they have a web address. I bought two (Pittman and Litton) 24V servomotors from them for a song a couple of years ago. Problem is, both motors are too large for the Gato. Either could turn both props direct. Great for a 1/48 or larger Nuke though. Any takers? Perhaps my bet bet is to try CC&H again.



Edited By Mermaid on 1142287886

[Guest]

Ah, okay.

What size is the

Ah, okay.

What size is the cylinder you're putting inside the hull?

Andy

[mermaid]

I'm considering building the WTCs

I'm considering building the WTCs into the hull as opposed to using a cylinder. However, If I do use a cylindrcal WTC, I imagine a 3.5" to 4" diameter would be appropriate. By the way,Country Cloth and Hobby's telephone number is]http://www.subcommittee.com/forum/icon_lol.gif[/img]



Edited By Mermaid on 1142344949

[mike dory]

Mermaid -- you might want

Mermaid -- you might want to talk to Jim Butt, He's built a Gato in 1/48 scale and has run it now for many years It's taken lots of awards at past regatta's too. Check the directory for his current e-mail address.

Another motor set up that works very well in your size boat is, Use twin pittman (Dumas) 6 volt motors, one per shaft, running on 12 Volts with a belt reduction of 3 to 1. It's one of my best set ups for 6 - 7ft. long boats. Best Wishes Mike Dory

[mermaid]

Thanks Mike. I wonder about

Thanks Mike. I wonder about how you can get away at running 6V motors at 12V. Wouldn't they tend to overheat? I've already contacted Jim and he suggested using two Pittman industrial motors driving the props directly. I have examined the Pittman Lo-Cog Servomotor specs and have concluded that direct drive is not a good option. I agree that a 3]http://www.subcommittee.com/forum/icon_question.gif[/img]



Edited By Mermaid on 1144164427

[mike dory]

Mermaid -- In all my

Mermaid -- In all my boats, that's 6 of them, that I've used the 6 volt pittman's on 12 volts,with the 3 to one belt reduction motor set up, Iv'e never had a heating problem in the last 40 years of of service with pittman motors, course this his old technology and I'm sure there are other systems that work just as well today. The thing about the 550, 600 & 700 motors is they draw a lot of amps. The pittmans draw half that of the others. When the big 1/32 scale Gato boats came out years ago, one of the recommended motor set ups for it was to run 4 pittmans, two per shaft on dierect drive. Well I wish you all the best. Bring your boat to the Carmel regatta, we'll sail together... Mike Dory

[bob_eissler]

Al's drive units are tops

Al's drive units are tops but the price matches. To see what you can scrounge at a hobby shop, view the images on my homepage (bob_eissler). The boat is a 1/40 scale type VII (robbe) which is similar to a 1/48 gato. I use 6v power supply with 2 motor controllers mixed together by the transmitter. I use 2 controllers because they were inexpensive but it is doubtful wether they would handle the current of 2 motors.

[mermaid]

Thanks again Mike. Specifically which

Thanks again Mike. Specifically which model of Pittman motor are you talking about? After all, Pittman/Dumas manufacture many types of motors. I plan to attend The SubRegatta this July but at this point, I'm just blocking out the Gato/Balao model. I won't begin building it until fall at the earliest. I've never built an RC sub before so I'll need all the help I can get!



Edited By Mermaid on 1144184883

[mike dory]

Mermaid - Check with Dumas

Mermaid - Check with Dumas themselves there number is 1-800-458-2828 I can't recall if the 6 volt are model number 2005 or if that's the 12 volt model. but it's one or the other. Just tell them what you want they will fix up right up. Sub tec. I believe is still carrying the belt reduction units. Be sure to tell Mike you want it for a Pittman/Dumas motors. All the Best Mike Dory