otherplanet

Nice attention to detail on the lights. I was going to comment on how bright the main top flashers were. Then I remembered being blinded the last time I was passed by an ambulance at night.

Hope the jerky motor is an easy fix. 

And a maximum of 8ma for the RX45 But to be honest. Most modern LEDs, especially the tiny ones you will want for this will be like a search light at that current. A 10k ohm will give a nice gentle glow with a surface mount led. A bit lower if you are building something modern. 

I agree with the above.

I generally use the Deltang 45 and 43. Depending on how many outputs and just how tiny I need to get. I have also tried the small 6xs for the more advanced functions, but not personally made good use for them. I think this is because they are more targeted at the trains.

If you are undecided between actuators and servos.

All of the 4x's have the 2F outputs you need for actuator control. But the F2 pin on the 43 is much harder to solder to, fine if you are practiced on very small pads but I would avoid unless you need the rest of the functionality. 

Servos are much easier to use and give a much better variable control and relatively much more force available. If you are just starting I would suggest do your first build with one and then move on to actuators. You can cut servos down a little but in reality you are more rearranging the components into a more useful and flexible shape,  this is still very useful if you are pushing the space limits. 

Actuators are much smaller, I have used the smallest of the complete actuators from Micron. But not the one which is just coil and magnets where you supply the pivot/structure etc. 

The force supplied by the actuator is just enough to steer the scammel scarab, but bumps in the road surface knock it off course easily. The gears of a servo provide a lot of resistance to such external loads.

It also gives most of its travel in the first 1/4 of stick travel, so whilst fully variable, it is very sensitive. They also seem to draw more power from your batter than a servo.

I would use a servo anywhere that will fit, move down to actuators only when you run out of space.

Lastly, and not on your list is shape memory alloy. SMA this is also available as nitinol. You power it using the F outputs. Its very tricky to handle, but some of the really small vehicles in Germany use it, including some of the N gauge ones. It requires very little volume but relatively long length. I mention it because you will see it around, and its the smallest, but I would not recommend it until you have really got the hang of everything else. (if then).

Finally, the biggest consumer of space is the battery. Really small ones are hard to find. Giles has a reasonable range available to him in O gauge, in OO, a lorry is reasonable but vans and cars, there are only a few, in N you will be really struggling. Less than 70mAh will give a very short run time and the maximum discharge current is directly related to the mAh capacity multiplied by the 'C' rating, again this makes it harder to find suitable components. Before you start using Lipos make sure you read up and understand them and their risks. You really dont want to get them wrong. (sorry if you know all this already)

Micron have a reasonable range but there are a few others, and the small sizes seem to come and go. The indoor rc aircraft and drone suppliers appear to be the most consistant.

I hope that all helps. Welcome to our very specialised corner of the hobby. Its a lot of fun!

Search. 1x3x1 bearing on eBay. Dozens come up at different price breaks 

I used this one.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F273512001979

Fantastic Giles. I could watch that on loop for ages. 

I am in the planning stages for a portable engine. So it will be stationary but running. The biggest challenge to me is how to get the motion running. Especially the eccentrics in OO. How how you solved the problem? Have you used the mill? Or have you been able to find a kit which is well enough made? 

At least I wont need the reversing gear.

Thanks

New toys arrived today from Shenzen. I'm not sure what I will use them on yet but the opportunities are obvious. (I do have a couple of thoughts though)

1x3x1 bearings, yes. 3mm outside diameter, 1mm ID and 1mm wide. 

Pack of 60 for a few quid. A quick test and they keep spinning when you flick them  so should help to reduce the friction in the drive systems.

Giles' recent traction engine video has spurred me on to getting the Dennis finally rolling.

Its just a trial run to make sure everything works Ok before assembly of everything else makes it harder to fiddle with.

still lots to do.

The reciever battery combo in the back is my prototyping setup, the final system should be a little smaller and neater.

Thats very nice Giles, I am jealous. A traction engine has been on my to do list for ages, but I havent got around to it.

It has a nice speed to it.

To Simond's suggestions: Plasti Dip silicone paint works well to add grip. But is difficult to get a smooth coating. My current project I have been making rubber tyres from square section drive bands, sold for repairing cassette players and dvd drives. I cut them down and glued to shorten them, although it has proved tricky to get a good joint, once acheived it seems to be stable. I used specialist rubber cyanacrylate.

I havent got the truck running yet, so I cant vouch for the durability. Maybe larger Xsection belts or rubber sheet could serve your larger scale requirements.

And you claim a Blacksmith approach! 

Amazing and inspiring, thanks for sharing.

The Roden Vauxhall D type ambulance appears in the pictures to have nice brass headlamps, although not exactly the same shape, but I havent bought that kit, yet. For a method for making something fairly similar. I file the vertical body of the lamp from a piece of round styrene rod. Put it in a pin vice to hold easier and work round gently with needle files and then emery paper. To create the brass lens, cut the flared end from brass top hat bearings and then glue on to the vertical body. Add the handle from a piece of fine wire and paint. See attached in 1:76.

Did you say you are involved with the prototype. I would be interested to know whether these were parrafin or carbide? My assumption would be that the upper lamps on the dash panel are parrafin / oil and therefore glow dull and yellow, whilst the lower main headlamps would be carbide, glowing whiter and brighter. I am interested from the perspective of what colour LEDs to fit. Good luck

Looks fantastic. I am very envious of your progress. Keep at it, I am sure it will all come together. I find that it's pushing the boundaries that make this hobby enjoyable. Once I work out how to do everything in a project it gets boring and I move on to something new.

Hence why I have so few duplicates of anything and probably why I rarely finish a layout.

If your interested, there are some UK OO versions in the radio control forum

https://www.rmweb.co.uk/community/index.php?/forum/228-radio-control/

JP is building an impressive fleet of his own.

Nice job. The scrolling display looks great. And it really adds to the operation.

I have now got the servo up and running. Other than minor trimming to the bearing mount for the potentiometer. It went together as planned. Its essentially the servo end of the model T chassis. But with improvements to clearances around the gears and the new potentiometer mounting arrangement.

Try Lee springs. https://www.leespring.com/uk_index.asp

We use them at work all the time. You can get very small diameter (sub 2mm) and your choice of spring rates forces.

Intriguing, They look very promising, I will be very interested to see how they go.

I haven't thought to search in German on shapeways. Although I have used it to look for components on other sites in the past.

The UJ is built from 2 tubes of 1.8mm OD 0.2mm wall thickness tube.

I cross drill the ends with a 0.45mm drill and then use a very fine piercing saw to cut the gaps out either side, and then a narrow file to finish the profile.

I then flatten the arms of the yoke by squeezing them in a pair of pliers. 

The spider is made from 1.2mm tube of slightly thicker wall section.

I use a 0.5mm piercing saw to cut a pair of slots into the end about 0.5mm deep.

This becomes a seat for two pieces of 0.45mm dia wire.

I cut two pieces of wire to a convenient length and then place them in a small vice at 90 degrees and squeeze the vice to create a matching set of dents so that the two wires sit in the same plane.

These are then soldered into place on the spider and trimmed to length, the completed spider can then be cut off the end of the tube.

Once the spider is finished it is fitted into each of the yokes by bending the arms out slightly until the tips of the wire can be slotted in. Then reform the arms back parallel.

This all sounds quite complicated, but its relatively quick once you have built a few.

I have some pictures from the build. I will get them off the camera and share them.

You have been busy!

I just saw the YouTube clips and came looking for the article.

Very nice work in all cases. I like the operating ramps, though perhaps you need a working tail hook release :-).

Have you seen the weighbridge on one of of the German Ho truck layouts on youtube. It measures the weight of loaded trucks and also shows the scale conversion weight.

Looks fabulous. Lovely detail and weathering. The drive motor is almost imperceptible, even when you know it's there. A great addition to the fleet.

Thanks Giles, your recognition is most valued.

I have been watching the progress of your mechanical horse, it looks really nice in the green. I am occasionally tempted to do a second Scarab, now I have learnt so much. But since Upper Benllech is now formally retired, it would be a bit redundant at the moment.

Happy New Year to everyone.

Its been a while and work on the layout has all gone a bit ‘armchair’ due to other commitments. So i decided to re-energise with a spot of vehicle building. I completed the mods to the servo CAD design and modelled up the transaxle for the Dennis subsidy truck. I also modelled replacement wheels with the tyres missing and designed some new acetylene headlamps as the military spec model only has one headlamp. All added to a sprue, the resulting collection of parts duely arrived from shapeways at the beginning of December.

Careful use of the dremell allowed me to hollow out the bonnet casting plus the crank case and gearbox sections of the chassis to take a 6mm gear motor. It’s quite steeply angled and not quite as perfect a fit as I had hoped, so its going to protrude into the cab slightly more than the original bulge in the floor. hopefully it won't stand out too much.

The transaxle went together nicely, it uses a 2mm dia worm and a 22tooth pinion to deliver drive to the wheels. My usual brass tube bearings are set into the SLA holes.

The grey shape in the top right is the original resin casting.

I’ve used brass tube and wire to build a pair of 2mm diameter universal joints on a drive shaft. this is glued to the motor at one end, and the input to the transaxle at the other. Since there is no rear suspension to compensate for, the small amount of freeplay in the UJ’s is sufficient to allow free running without requiring a spline connection.

I managed to achieve my objective of getting the wheels turning before the end of 2018 (on the 29th), they run very smoothly and satisfactorily at a reasonable slow speed. If needed I can change the worm to a 2.8mm diameter with the appropriate reduction in pinion to make it faster.

2019 will aim to get the servo built and working; since I have “improved” the design I hope it works OK. I also need to try out the plan to make tyres from square rubber drive belts to go on the wheel rims. But most importantly, I need to get the new camera working; which is suitably tiny but at the moment I cannot get an image out of it.

Lovely work as usual Giles. Impressively quiet too, you can hear the dashboard clock ticking, or maybe that is the servo.

Looks like the trailer reverses nicely.

Are you going to paint it in Denton corporate colours, or will it be making deliveries to the mill?

Several of the Rx43s can actually handle 800ma on 1 channel and you can also connect the Add2 to get 3A. But also, those with 2 or more H bridges you can assign two 400ma outputs to one channel. So use H1 for one bogie and H2 for the second and just reprogram them using the programming instructions to change the assigned channel. No need to bind multiple receivers.

Good luck

Edited to correct Rx45 to Rx43

Concerns have abated following trials of alternate vehicles. The Atkinson can only cope with this incline before sliding back down the hill. (even when just placed statically on the sloping surface).

However. The K8 will cope with this incline.

Any steeper and it starts to topple backwards on its rear wheels. But still doesnt slide.

It cant quite climb this angle, having insufficient torque because it is too highly geared. But at only a few degrees lower it will happily run up the test track.

Overall I am happy. Even the Atkinson can climb more than I need. but some further experimenting with rubber tires and or plastidip is definitely worth the effort.

Meanwhile the road surface is not the limiting factor even in its slightly smooth and glossy state.

Additionally, my efforts with the static grass (which I have never used before so excuse the imperfections) seems to leave the surface navigable even when placed between the ruts.

Its not up to the standard of Pikey's hill climb trials track, or landrover, but comfortably meets my needs.

I am loving that landrover, it drives really nicely and looks so good climbing those slopes. I look forward to seeing the fully detailled scenics.

I was tempted to do a series 1 for Upper B before the invites dried up.

However this sets the bar very high. I think I need to go back and reassess my test Road.