I have an M18 that I'm trying to wring a little more speed out of... It's fitted with a Tamiya sherman DMD and MF currently. I know people that know people that have run them on 12v in 1/6 scale vehicles, but what I don't know is whether the extra voltage gets passed on to the things that the 1/6 scale guys might not have used - i.e. the flash, TBU and IR LED. Has anybody experimented with this successfully, or should I be nervous about things going pop?!?

(Secret option B might be to try El-Mod - I don't have a problem with blowing up a $15 HL flash unit in the name of science, a $50 Tamiya flash unit is a different proposition...)

Should probably add: I'm thinking of 7 cell 8.4V or 8 cell 9.6V NiMH packs, no more than that.

You are a brave soul Sir, I would never experiment with my Tammy gear. I agree, that sounds like a job for a HL or IBU (they are super cheap right now if you contact Jerry).

Personally, I wouldn't look at voltage but gearing. I would try a smaller tooth pinion or re-work some of the gears in the box. Maybe a new, hotter motor (or de-wind it yourself) but watch the advertised amps it pulls.

I know the original Tamiya Tiger I gearbox (white gears) was much too fast so that's where I would go.




Jeff

Its using HL gearboxes, so not so many options on gearing - I did try picking up "faster" motors before I left the US, but they draw way too much current for anything I can drive them with (the specific ESC for them is rated at 69A apparently!)
Original Tamiya DMD 'racing' gearboxes are like hens teeth as well

I did think of Lithium based batteries as they can support much higher current draws?

In Europe we are really starved for decent brushed motors, so option C would be to hang out for Brushless compatible battle boards...

Hen's teeth are not that rare. You know how to contact me and I might have a set or two lying around. Do you want with or without final drive shaft reinforcement? I'll check in the AM to see what's in my stash. Be advised that shipping will be a little slow from here.

The nice thing about it is you could actually use two different voltages. the units are powered separately so you could run normal 7.2 too the things you are concerned about and the higher voltage where needed.

The Clark TK60 can handle 3s (~12V/60A) so it should easily push powerful motors.
However, you can probably go fast enough with 2S. We had a meeting today and a friend brought his HL Panther with WH board (new Chinese brand) + DKLM PDSG gearbox (fast gearing) + 2S Lipo.

That thing was insanely fast while retaining the legendary torque of dual-clutch gearbox at climbs. It was so fast that I think if it goes any faster you will not be able to control. It achieved at least 100km/h scale speed.
Also keep in mind that your M18 is a lighter tank and will likely go even faster. I am going to get the fast PDSG for my under-construction Tammy Leo1. I already have the medium speed one on my Centurion.

The Tamiya DMD has a voltage regulator built in so no increase in speed possible that way.

I regularly run some of my tanks with 8.4V batteries with no issues (the voltage regulator has a voltage range it can work with)

As previously said, use a gearbox ratio mod to get more speed.

Ok, good to know. The thought behind the voltage increase was that I need to buy new batteries anyway, so it would have been a cheap and easy fix.

Willy did some "testing" on the DMD years back to see if putting them in the 21st centrury Stuart's was a viable option. He ran one up to 14V and found running at 12V wouldn't be a problem unless you had massive amp draw.

Hi Martin , have you thought about speed 400 6v motors plus lipo 2s battery ,this combination should give you more speed through the standard heng long gearboxes. The speed 400 6v are a lot faster than the 7,2 volt and draw more amps , the speed of a 7,2 motor is 2,227 per volt, the speed of a 6v motor is 3000 per volt. see link http://calbugs.com/http___homepage.n...s_graupner.pdf.
should be fast on the flat but may be hard to set off up hill.The run time will be lower using the 6v motors (they blow the RX18 boards as do the 480 motors)

regards pete

Those would be great motors Pete and along with gearing PLUS voltage... the combined 3 areas would increase the speed.

Looking at advertised RPM ratings is important.





Jeff