Scratch built Typhoon advice needed

[Subculture]

So you didn't mention the tooth count of the Emaxx gear, but a quick google throws up something around 65 teeth, so along with the other stage of reduction I get around 16-17:1 overall reduction giving a free running spindle speed of around 750-800RPM. That is good about the right speed and reduction.

You mentioned earlier the tanks were drawing a lot of current. What was the figure?

[Mermod]

As is the draw kicks in a 5 amps then drops to about 3.5.
yes the spur gear is a 66t 55mm diameter, i had the second one ready for the other tank in a box of goodies, turns out i engraved the o ring details on the tank end caps plus the date when it all went onto storage, the 3rd of July 2014 which got me thinking about the o ring grease sitting in tank, stripped it all down and it kinda feels like old glue so I'm currently cleaning everything, I wouldn't mind doing away with the small fragile gear setup and putting the spur gear straight on one of those planetery units then straight onto the traxxas pinion, any suggestions?

Thanks again
Phill

[Subculture]

Okay so going back over the figures I realise I made in error in the first stage of gearing, and your final ratio is taller at around 10.8:1, which would stretch the motors somewhat.

if you wanted to use the motors I linked to, then bear in mind the output shaft will be larger than your 500 motor, so the pinion will need machining or you can order a new pinion with the right bore.

The tanks will be slower to fill, estimate 25-30 seconds but should only draw a few watts free running, all assuming nothing is binding up.

[Mermod]

I'm torn between the 540 or 385 motor versions, I have a habit of overdoing things, perhaps I should go with the smaller of the two.

[Subculture]

Either will work.