Live diesel monster, CFG + FEVE

Try this- it's much cheaper. Use a short section of flexible polymer tubing as a coupling. Get the tubing in a slightly smaller diameter than the shafts. Look for a thicker wall tubing if available. Force the tubing ends over the shafts - perhaps with a touch of contact cement to hold them on.

Good idea Bill but I am looking for something with an order of magnitude torque capability of
about 1 Nm (a pure guess) and the ability not to deform at up to 10,000 rpm.

Can a piece of polymer tube get anywhere near this ?

I don't know how much torque it could stand. Perhaps some reinforced hose, like fuel line hose would be better.

Help please Carl,

Do you think it is a necessity to have a DPDT switch, that diverts battery power between the speed controller and the DC generator, with a centre off facility.

I am trying to do this remotely with "off the shelf relays" and it would be easier without a centre off. This would require the speed controller to be used as the off position to stop power from the generator moving the locomotive during nitro start up.

I have to date no idea whether the speed controller can just absorb the power from the generator until throttled up and therefore dispense with the 3rd position on the DPDT relay.

The whole point of this is to be able to remotely start the loco and also to switch to battery power remotely when the nitro runs out fuel or fails.

If you think this is potty and I am trying to run before I can walk please say.

Thanks as usual,
David

A centre off is not absolutely necessary but seperate manual off somewhere is useful for safety isolation and fault finding.

The speed controller won't do anything until activited by the radio control irrespective of the amount of electricity supplied to it providing it is within it's working limits.

The lower threshold of mine is about 6 volts.

There is another issue here in that the speed controllers and receivers are often designed for BEC (RX batterry eliminator) working.
That means the receiver operation functions by power supplied transparently from the speed controller.
If there isn't enough electricity to operate the speed controller (below 6volts) then the reciever will not work either.

So I do not use the BEC circuit on the speed controller (it is just shorted out) and the receiver uses a conventional 4.8 volt supply separately.

In theory it wouldn't matter because you would need both to be working before being able to do anything.

But in practice with using the BEC there is a delay and the speed contoller operates before the receiver and for a brief period supplies electricity to the bogies which results in a lurch.

Hope this makes sense.

Hi Carl

Could you inform me about these I P Engineering power bogies please as I plan to buy a pair of them as they are relatively cheap.

http://www.glendalejunction.co.uk/IPHomeBuild.html

As I do remember you saying you had a pair?

I don't actually have these type of bogies Anton.

These are a relatively new production from IP since they invested in a laser cutter.

I'm not sure about them as they are wood.

£25 each.....mmm

A cheap motor, plastic gears, middle quality wheels, wooden frames, driving just one axle.

I wouldn't use them for a heavy locomotive to be honest.

Alternatively the Pline power bogie made from all metal is available and i have been emailing the guy for prices and he wrote back as follows:

http://www.pline.biz/home-builder-parts.php

1. A cub power bogie for 6v DC with 1:18 single stage reduction, powered by 75gmcm torque/2500rpm perm motor. Price GBP30 per pair
2. Cub power bogie with 1:32 single stage reduction for 6v dc powered by 75gmcm torque/2500rpm perm motor. Price GBP32 per pair
3. Bo-Bo power bogie with 1:36 dual stage reduction for 0-18v dc powered by 150gmcm torque/7500rpm perm motor. Price GBP120 per pair
All our power bogies have brass side frames, spacers, bolster blocks and bush bearings. Axle boxes, milled brass. All metal gears, wheels are steel with high impact delrin hub bushes for insulation
Axles are spring steel, dia is 3mm, wheel dia varies between 20mm-32mm(tread)
Add shipping to the UK @ GBP12 for a pair of power bogies.

David has warned me about buying from abroad and a definitely see where he's coming from but what do you think of these?

Anton, have you thought about using a pair of PIKO Taurus bogies they are reasonably cheap and strong, also Aristo or USA trains do bogies if you can find them.

http://www.piko.de/produkt_db/check.php?page=detail&grand_id=3&parent_id=23&child_id=0&id=36100

I think pline are quite reputable but I would worry about my £120, maybe not my £30 though

Hi Patric
Thank you for the link....i have never heard of piko before and its good find all my options. Yes i was never going to consider spending £120 but £32 for a two complete brass bogies sounds reasonable.

Some of the stuff on the website looks very interesting and useful.

There are certainly products there that I could use.



Have you seen these:
Lego train motor bogie

I think they are 38mm gauge but maybe you could modify.

Or this for motors...shame they're in Australia.
Surplus motors

Piko do recommend a 2 amp supply, (for a twin bogie loco) I know my BLG 1amp supply did not have enough oomph for the taurus, but runs fine with a 16v 2.75a DCC supply. How many amps does your system throw out ?

Anton, 2 things.

I am not aware that Pline have sold any of their bogies in the UK so I would not buy without visiting the agency at Cleethorpes to check on quality.

Are the Piko Taurus bogies 45 or 32mm ?

Tx
David

@David - 45mm's

Ahh thats a problem as I im only using 32mm products.....hmmm well ive been emailing the guy at Pline models and for around £30 I cant really go to wrong. He has said i can have a wheel base of up to 100mm so this is very helpful in getting the correct size for the Hymek as a small wheelbase would just look to silly.

Anton, the Pline bogie at £30 is pretty basic, is 6 volt with plastic gears. Caveat Empor.

Carl, any idea how to incorporate a pressure tight filler cap on a soldered up brass fuel tank.
I am running out of space so need to customise.

Tx.

I think a threaded arrangement would probably be easiest to do if you make the top thick enough or solder a 3mm washer for strength.

Drill out with say a 3.5mm drill and thread with a 4mm tap.

Or solder a nut on the top after you drill out a hole slightly bigger than 4mm. Put a steel bolt in the nut to centralise the hole while you solder.

Then you just use a 4mm bolt/set screw etc as a filler plug with a rubber sealing washer. Of course you could make it bigger if you want.

Carl
Would you mind telling me the wheel base on you monsters bogies and what you think a good/standard 32mm wheelsbase is? Also what you would consider for a loco chassis that is 19 inch long and 4inch wide

Sorry part of that question is aimed at David as well as I know he's the man for 32mm gauge

Anton,

My FEVE monster is 20 ins long with a bogie wheelbase of 2 1/2 ins and a distance between bogie pivots of about 12 1/2 ins. These dimensions are approximately those of the Welsh Funkeys at 16mm to the foot scale but I am modelling at 13mm to the foot on 32mm gauge to represent a prototype of about 750 mm. The model is therefore a bigger prototype on my railway than the Funkeys are in 16mm.

I dont know if it helps but here are some 3 ft and metre gauge prototypes. First figure is overall body length, second is wheelbase and third is distance between bogie centres, all in feet.

Soller motor coach 40/7.5/27
Creusot Diesel (Majorca) 44/7.5/29
Brissoneau (Corsica) 40/7.5/24
Breda Centre Cab (Sardinia) 33/6.5/19

So to summarise I am using 32mm guage but not 16mm scale and obviously all proportions will be unaffected.

Yesterday I visited a very friendly and extensive rc model shop. I explained about the issue of aligning the nitro and generator shafts and asked about the drive train on a nitro car/buggy.

The proprietor then showed me the inside of on of these vehicles. Apologies to those who are familar with these things but there were a few surprising (to me ) conclusions.

- The clutch unit is self contained and screws directly on to the prop shaft.
- There was a 3 to 1 gear ratio with a drive shaft on both forward and rear axles so that alignment problems are limited to gear meshing ones.
- The drive between the motor and the axles was completed with a T bar engaged in two slots in a hollow tube and at 3 to 1 was presumably rated at about 5k rpm
- The base plate with all the holes and fixtures could be obtained, along with all the other spares and it was estimated would cost abot £35 in total for a loco.

Any comments on how practical this might be and how such a crude universal joint (Tbar on one end.two slots in hollow tube for the other) might cope with he forces between motor and generator, if in fact they are greater than on a nitro car.

thank you very much david for posting that

and sorry im a bit confused here....did your rigid coupling snap? and your now thinking of incorporating some kind of gearing from a rc car to attach engine and generator?

quick question....does this locomotive featured here use a gearing system that you are trying to incorporate on your loco?
http://www.mylargescale.com/Community/ForumArchives/tabid/100/Default.aspx?TOPIC_ID=42371

as it looks like this one has the clutch bell and everything still on and uses a gearing ratio

Yes Anton my expensive and 12k rated flexi coupling snapped after less than 1 hours running. The stresses that caused the failure may have been due to the fact that I had the dc motor floating and this could have caused the break due to excessive oscillation, but this is purely anecdotal.

Therefore I need a coupling and do not have access to a lathe at present. Consequently I was looking at a radio control car in my local model shop to see how the drive train works on a car.

It appears that the main drive incorporates clutch, gears and a semi universal joint. The clutch is, I think, of no great value but the gears and joint may be useful on a loco to avoid shaft alignment.

What I cannot get my head around is how the car had a simple slot in either side of a hollow tube engaged by a transvers rod on the transmission shaft can be sufficiently robust (and makeable) compared to the complex flexi coupling that failed in my experiment.

I know the gearing, at 3 to 1, and maybe the clutch, helps to reduce the forces but I am surprised such a basic T bar design could handle say 15k/3 ie 5000rpm. I wonder whether to buy the parts and try it, one could possible use the car base plate to resolve seating and alignment issues.

Any thoughts would be most gratefully received.

It could be a way to go David. At one time Conrad's were selling a glo plug racing car chassis complete for 150 euros but sadly no more.

If you are going a long this route you could add another set of gears and just run it entirely mechanically.

I bought some gears and a clutch too BTW, and will experiment when I have some time.

As for your coupling....That was a bit naff and I'm surprised that it broke even with the motor movement. Just shows who sensitive and fragile these fexible couplings are.

I notice that Bob Pope and Jerry Hyde have used huge Oldaham type or similar couplings.

Brief progress report on the big ugly FEVE loco is :-

1. All relays, fuses and electronics installed in chassis
2. Two Essel motor bogies installed in chassis
3. 2.4gb Receiver and Electronize ESC installled in chassis
4. Chassis tested under battery power only and signed off as fully functional.

Main oustanding tasks are

1. Try to get the Oldham coupling.
2. Install ic power generator unit into chassis.
3. Test run under ic power.
4. Build and fit body.

Main issues outstanding are

1. Designing the loco body to fit within my railway's loading gauge.
2. Shaft alignment and a successful coupling.
3. Body made of wood, brass or plastikard. Brass is too heavy and would take too long. Plastikard is the easiest to work but goes brittle and could melt. Looks like ply again.
4. Summer has started and outdoor tracklaying is a big distraction from being driven insane with a live diesel.