Taken the plunge - modern image 00 gauge Transit van RC conversion

[Robin2]

Is that a Deltang receiver? Which model?

 

...R

[Pikey]

Yes, RX-45. With lead-out wires and connectors added by Andy at Micron.

[Pikey]

First test a success. Battery didn't run for very long, guess it wasn't charged.

 

 

[Robin2]

I'd appreciate it if you would put your movie on YouTube (or similar) so we don't have to download the file.

 

...R

[Pikey]

I've since finished the bodywork and it has successfully completed its first proper test drive

 

https://youtu.be/9UtMubASFa8

 

I'm quite pleased. It seems to start with a bit of a jerk, but that may be something I can tweak with the transmitter settings. Obviously its a bit of a frankenstein's monster, with the servo sticking out through the windscreen, but the whole point was to get something relatively easy up and running fairly quickly without worrying too much about perfect detail and hiding all of the electrics. Total cost so far is about £210, but included in that is a transmitter (£70) and a battery charger, (£20), neither of which I will need to buy again. So approx £120 for the van itself, including the original model.

 

So, I'm kinda hooked  I've ordered a Scania 6 wheel curtainsider, which should be much easier to do than the van. I've also ordered an AEC dropside lorry, which I'm going to convert for my dad to run on his early 60s steam/diesel layout. And a Scania 8 wheel flatbed lorry with crane, which will be a tricky one as they have two steering axles. But I like a challenge

[Titan]

Was a bit worried about the p-way crew for a moment!

[Pikey]

Yeah, I didnt really pick the best place to reverse there did I

[Robin2]

Rather than being worried for the P-Way gang I was very impressed by your driving.

 

The cost (even at £120) is a bit eye-watering, however.

 

...R

[Pikey]

https://youtu.be/l89jmOi9E9I

 

Dug out an old Metcalfe model of a petrol station, and drove around it for a bit

[Enterprisingwestern]

Based on your user name, it's not your Transit it's modelled on is it?!!

 

Mike.

[Pikey]

Ha  

 

Tarmac yer driveway?

[otherplanet]

That runs really nicely, I think it's worth making the mods to hide the servo, incidentally if you go for the linear ones. They come in left and right handed versions. Unless you're transmitter has the ability to easily invert the steering direction. You need to get your linkage and servo All the right way around. Or it will turn left instead of right.

Speaking from embarrassed experience!

Looks really good though. Im glad you have the bug and I'm looking forward to seeing the next build.

[Giles]

That's great to see!

 

I suspect with these small motor/gearboxes (I have a couple) that the motor only spools up at a higher start voltage than we would like, so they go from 0 to ten mph instantly, unlike the Polulu gear motors (very much larger) which spin over slower, sooner, at lower voltages. I should very much like to be wrong though!

 

Best

 

Giles

[otherplanet]

Yes they can have a very narrow operating range. In their origins as vibration motors they only needed to start and stop. There are a range though.  If you look at somewhere like precision microdrives, they give the full technical specs, including power graphs. They actually sell 2 motor gearboxes with the same dims and voltage bur different speeds. Due to the motor windings. But ultimately at this size we seem to be limited to a low maximum speed, or a jumpy, start to a higher than desirable min speed. Getting maximum smoothness in the drivetrain helps, but Watching the German videos on YouTube, they seem to struggle too.

[Robin2]

It would be interesting to know if the low speed running could be improved with some form of motor speed detection and feedback into the control system. But there is not much space in such a small model for that added hardware. And of course you would need to reprogram the controller.

 

A QRE1113 reflective optical detector is both very small and convenient to work with (i.e. they are surface-mount size but have long legs that are easy to solder) and maybe one could be positioned to detect stripes on the inside of one of the driven wheels - just thinking out loud.

 

I am using one of them to detect the speed of a small motor in an 00 Gauge loco - but, of course, the available space is much larger than in a Ford Transit.

 

...R

[Pikey]

Some more lorries have arrived for conversion. There should be plenty of room inside this one:

 

 

 

This chassis almost looks as if its designed for an RC conversion - space between the chassis rails for a motor, central recess over the front wheels for a servo, loads of room in the rear for a battery and receiver

[Pikey]

Finally modified the ramp so that my van can get up onto the concrete yard slab without grounding. So I can now make deliveries to the depot:

 

https://youtu.be/XWBBQM8UG-E

 

I should be starting the conversion of the next lorry this week, when my next shipment of motors and steering axles arrives from Germany/Poland.

[37038]

That is amazing! Once the indicators work it will be a work of art

[Robin2]

I dunno. It's a bit crap really. I was expecting the driver to get out and walk round and open the rear doors!

 

...R

[otherplanet]

I love the green tinged 'security camera' effect on the gate. 

Nicely done.

[Pikey]

Latest delivery from mikromodellbau has arrived, including these brass gears which are soooooooo tiny  

 

[Pikey]

So, I'm working on the conversion of three more models, all lorries. The Eddie Stobart curtainsider in the pictures above, and these two:

 

 

The Scania flatbed will have working lights (including indicators, hazards and reversing light), and spotlights that I can hopefully flash independently of the headlights. Plus I will have a second motor for raising and lowering the ramps at the back, to load things on and off. Conveniently, my transmitter has a two-stage 'flaps' switch (for model aircraft), which has fully customisable settings - so I'll set the middle position of the switch (which on a plane would be flaps stage 1) as zero, then I can toggle the switch up to operate the motor to raise the ramps, or down to lower them. The truck also has two steering axles, which adds a further challenge to the conversion! I'm leaving this one til last, for the moment.

 

The green truck on the back is an AEC Mammoth, which is obviously not my era. I'm converting this one for my dad, who has a 1960s branch line station and goods yard layout in his garage. There is a road down to the station which goes up a lane and over the railway bridge, but the lane is quite steep and bumpy so I had already concluded that I'll need to drive both rear axles - or the lorry will never get up the lane. That's what the tiny gears are for. Here they are mocked up in the drivetrain arrangement:

 

 

So I'll have the motor mounted slightly off-centre, driving the main propshaft, and then worm gears and matching axle gears, giving a final drive ratio of about 55:1 (I think). This should drive slightly slower than my Transit van. Here are the axles installed:

 

 

I've cut away all of the middle of the chassis, and I'll make some brass bearing blocks to hold the propshaft in place, I'll either use some 2mm tube to hold the prop, or some of the little 3mm bearings from Mikromodellbau. I've made a mistake by opening out the axle holders to 3mm - before realising that the top and bottom arent actually in line, so I cant use a 3mm bearing! I could maybe use 3 of them stuck together, but as that actually wont function as a bearing I might as well just use a slightly bigger diameter tube. 3mm tube with 2mm tube inside it to carry the 1mm axle. Bit of a faff.

 

I opened out the centre bore of the plastic wheels to 2mm, then glued in a 2mm brass tube as a sleeve, then glued the 1mm diameter brass axles into the sleeve. It works very nicely. Here is the front steering assembly (kit from mikromodellbau, identical to the one used on the Transit):

 

 

Nothing fancy as far as lights are concerned for this truck, but I hope to have functional headlights and indicators.

[Pikey]

Bearing blocks with 3mm brass tube pressed in, which will be glued to the chassis. These hold the 1mm propshaft with 2mm sleeves through the 'bearings'. Axles are 1mm with 2mm sleeves through 3mm 'bearings' which are glued to the chassis. I need to make more space for the motor.

 

Edited July 13, 2017 by Pikey

[Robin2]

Looks magnificent.

 

...R

[Pikey]

So I've now worked out the technique for glueing the brass pieces to the aluminium pieces - not before accidentally glueing one of the gears to the shaft in the wrong place though!!

 

If you put a dollop of superglue onto a surface it wont stick to (like a little plastic bag), and scrape it up with the head of a pin, you can use the pin to transfer tiny drops of superglue to the exact area you want it. I've successfully used this technique to glue everything in place, but I'm going to have to make a spacer or something to stop the axle moving and the gears disengaging, because I've glued the cog to the axle on the wrong place. It also means the rear wheels are going to stick out a tiny bit. Very annoying at the time, but I suppose no-one will notice really.

 

I also slipped with the Dremel whilst removing material from the wheel arches, and cut one of them off! Actually not a disaster, because I can trim them and glue what's left to the cab, leaving space inside them for full articulation of the steering front wheels.

 

I'll glue the motor in place tonight, but not with much glue as I'm not sure the ratio is correct so I might want to change the size of the gear on the end of it - which would mean removing the motor and re-mounting it in a different place.

 

Getting everything lined up was more luck than anything else - neither of the axles are horizontal, and the prop is on a bit of an angle as well. It seems to be balanced well enough though, all six wheels are touching the ground anyway. May need a touch of weight over the front end to ensure the steering works properly. I do hope it works. Radio gear should arrive in a few days time, so I guess I'll find out then!

Edited July 17, 2017 by Pikey