Making a G gauge Flea Drive

E

Exador

Registered
7 Nov 2019
6
8
64
Southern California
For awhile I have been toying with making a small drive for critters and such. I was dismayed to see most motor blocks priced at $50+ on eBay. All were to closed spaced on the wheels for the critter I envisioned. I decided to attempt a custom drive for much less and managed to succeed. I found the following drive unit on eBay for about $1.20. BTW, I'm using a plastic wheelset because I am planning on RC/Battery drive but this would apply to LGB metal wheelsets also.
The drive unit:
new_unit.jpg


I opened the unit, removing 2 small screws and the plastic band holding in the motor.

exploded.jpg


I re-drilled the drive axel on my Unimat.

lathe.jpg


I then cut off the overlap of the drive axel with a cut off wheel.

drive_axel.jpg


I reassembled the motor

closed.jpg


and disassembled the wheelset. I removed the center plastic spacer.

wheel.jpg


I had gauged my drill to be a press fit for the axel. Next, I pressed the axel and one wheel through. I then pressed the other wheel on AND!!

done.jpg


Voila! My Flea was complete. It runs surprisingly well. I plan on using 2 drives for my critter. I had the plastic wheels so total cost was under $3.
Hope you enjoyed my post. Please comment. Exador
 
dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
25 Oct 2009
16,365
1,110
71
St.Neots Cambridgeshire UK
For awhile I have been toying with making a small drive for critters and such. I was dismayed to see most motor blocks priced at $50+ on eBay. All were to closed spaced on the wheels for the critter I envisioned. I decided to attempt a custom drive for much less and managed to succeed. I found the following drive unit on eBay for about $1.20. BTW, I'm using a plastic wheelset because I am planning on RC/Battery drive but this would apply to LGB metal wheelsets also.
The drive unit:
View attachment 260810

I opened the unit, removing 2 small screws and the plastic band holding in the motor.

View attachment 260807

I re-drilled the drive axel on my Unimat.

View attachment 260808

I then cut off the overlap of the drive axel with a cut off wheel.

View attachment 260809

I reassembled the motor

View attachment 260811

and disassembled the wheelset. I removed the center plastic spacer.

View attachment 260812

I had gauged my drill to be a press fit for the axel. Next, I pressed the axel and one wheel through. I then pressed the other wheel on AND!!

View attachment 260813

Voila! My Flea was complete. It runs surprisingly well. I plan on using 2 drives for my critter. I had the plastic wheels so total cost was under $3.
Hope you enjoyed my post. Please comment. Exador
Very interesting, just wonder how the nylon gear will cope with the press fitted metal axle. I note that you have a Lathe, I would guess that you made the interference fit to be not many thou’s of an inch. That would help longevity of that union.
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
26,676
1,066
North West Norfolk
G scale drive units are a tricky area. Mostly because of the varied type and weight of rolling stock that folks use in this scale/gauge/arena.

Ivan at IP Engineering has been producing drive units for probably the longest period in this country, and wile his have mainly been successful, they have struggled where people have required heavier loads.

In the quest for cheap and cheerful, my mos successful drive unit was a 25mm wide strip of aluminium bent into a U shape using a vice, with a nylon worm and gear from an old Bachmann bug mauler. Brass bearings for the axle salvaged from somewhere or other. It had to be cheap, as I was out of work at the time.

The other issue, and the Achilles' heel of this cheapo unit was the gear ratio - I had no choice, I had to go with what was in the parts bin.

In the UK, there are now a few 3D printed drive units at around the £25 - £30 mark, but the gear ratios are still a bit high, and when my Yeti chewed up the brass gears in the most recent cheap gearbox, the 3D printed case didn't stand up too well.

However, you have to remember that I don't have many lightweight wagons, and therefore am asking the drive unit to do quite a bit of work.
 
dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
25 Oct 2009
16,365
1,110
71
St.Neots Cambridgeshire UK
G scale drive units are a tricky area. Mostly because of the varied type and weight of rolling stock that folks use in this scale/gauge/arena.

Ivan at IP Engineering has been producing drive units for probably the longest period in this country, and wile his have mainly been successful, they have struggled where people have required heavier loads.

In the quest for cheap and cheerful, my mos successful drive unit was a 25mm wide strip of aluminium bent into a U shape using a vice, with a nylon worm and gear from an old Bachmann bug mauler. Brass bearings for the axle salvaged from somewhere or other. It had to be cheap, as I was out of work at the time.

The other issue, and the Achilles' heel of this cheapo unit was the gear ratio - I had no choice, I had to go with what was in the parts bin.

In the UK, there are now a few 3D printed drive units at around the £25 - £30 mark, but the gear ratios are still a bit high, and when my Yeti chewed up the brass gears in the most recent cheap gearbox, the 3D printed case didn't stand up too well.

However, you have to remember that I don't have many lightweight wagons, and therefore am asking the drive unit to do quite a bit of work.
When I was into 0 gauge I used the MSC Gear Box Drive Motors, certainly the XL would IMHO take pretty well anything that one would throw at it, so strongly put together it is.


Certainly not as cheep as $1.20!
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
26,676
1,066
North West Norfolk
When I was into 0 gauge I used the MSC Gear Box Drive Motors, certainly the XL would IMHO take pretty well anything that one would throw at it, so strongly put together it is.


Certainly not as cheep as $1.20!
I've just splashed out the best part of £100 for an MSC motor/gearbox (2 stage) for Yeti - so far so good, but I'm poised because I went back to meddle with some sound :wait::wait:
 
E

Exador

Registered
7 Nov 2019
6
8
64
Southern California
G scale drive units are a tricky area. Mostly because of the varied type and weight of rolling stock that folks use in this scale/gauge/arena.

Ivan at IP Engineering has been producing drive units for probably the longest period in this country, and wile his have mainly been successful, they have struggled where people have required heavier loads.

In the quest for cheap and cheerful, my mos successful drive unit was a 25mm wide strip of aluminium bent into a U shape using a vice, with a nylon worm and gear from an old Bachmann bug mauler. Brass bearings for the axle salvaged from somewhere or other. It had to be cheap, as I was out of work at the time.

The other issue, and the Achilles' heel of this cheapo unit was the gear ratio - I had no choice, I had to go with what was in the parts bin.

In the UK, there are now a few 3D printed drive units at around the £25 - £30 mark, but the gear ratios are still a bit high, and when my Yeti chewed up the brass gears in the most recent cheap gearbox, the 3D printed case didn't stand up too well.

However, you have to remember that I don't have many lightweight wagons, and therefore am asking the drive unit to do quite a bit of work.
there is an all-new version of this gearbox for $3.29
s-l500.jpg
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
26,676
1,066
North West Norfolk
That doesn't look bad, and would be a cracker for railbuses, railtrucks and the good ole VW Drasine :clap::clap::clap:
 
FatherMcD

FatherMcD

Registered
13 Mar 2014
57
18
Idaho
Would you mind sharing the actual link? The closest I've found is this: s-l1600.jpg at over three times the price. Thanks.
 
E

Exador

Registered
7 Nov 2019
6
8
64
Southern California
Fred2179G

Fred2179G

Registered
20 Apr 2017
398
87
USA
I can buy those metal geared motors for $2.56 from china.
US $0.93 27% OFF|DC 3V 6V 1:90 Metal Gear Motor All Metal/Half Metal Single Axis Gear Motor Robot Intelligent Vehicle Speed Reducer TT Motor Blue-in DC Motor from Home Improvement on AliExpress

I also used a similar but smaller motor, all metal and it came with a 3mm shaft [which turned out to be one side only. See Large Scale Central - Advanced Forum Detail Topic - Delton Doozie Gearbox]



As you will read though, it ran very slowly due to the high gearing. 1:90 is a bit much (the blue one.)