Dapol class 121

[1018509]

I like these DMU's but getting one in green with or without speed whiskers is nigh on an impossibility.

What to do - my (pricey) way was to buy a couple of green dummies from Hatton's the last two it seems, and a couple of class 121/122 chassis from DCC supplies and have a body chassis swapping orgy.

The first body swap went well although it was fiddly and the wiring is a nightmare to get out of the way when re-assembling so much so that I cut the seating insert down in the guard's area where it doesn't show anyway. Once you get over the dread  of pulling your precious model about the rest is easy.

A complete disaster on the second unit as I managed to pull off one bogie pick up and several decoder PCB wires during re-assembly so I had a cup of tea and tackled the job from a different aspect.

I removed the motor from the now useless (new) chassis and re-assembled it in the dummy this needed the supply and soldering the motor to decoder PCB, I was nervous about this but as long as the heat is removed as the solder melts no nearby components or soldered connections are affected and, more importantly, these PCB solder points are on the edge of the PCB not too close to other soldered connections, unlike the ones I previously ripped off

The dummy chassis and motor chassis are different - the powered chassis has metal weights the dummy's are plastic one of my DMU's has one plastic weight and one metal as one metal one wouldn't fit. The powered chassis have no headcode/destination lights; the dummy chassis has no motor wires.

My next project is to wire in two micro LED's for the headcode/destination indicator and power it via the lightbar connection so that both end are always illuminated. I don't like Dapol's bright in one direction and dim in the other - I can't see why these lights need to be connected to the decoder pcb other than for their power supply.

I suppose that together the two models cost me about £50 more than Hatton's pre order price but I want my DMU's now not when Dapol can be bothered to produce them so I'm happy.

It all begs the question as why aren't the motors, drives shafts, gears etc available as separate components - I hope no one is going to tell me they are now I have spent the money.

[Vanders]

I also recently did a body swap, and detailed my exploits in the other place. I agree that the are fiendishly difficult to re-assemble, although luckily I did get everything to work again once I've finished. Quite how they actually build these things at the factory is a mystery. It isn't something for the faint of heart to tackle, I'd reckon!

[Michael Hendle]

Hi

I'm glad I read this, as I was thinking of doing the same,I thought it would be a simple case of taking the body off the dummy and placing it on the chassis of the motorised 121\22.

Mike

[1018509]

I also recently did a body swap, and detailed my exploits in the other place. I agree that the are fiendishly difficult to re-assemble, although luckily I did get everything to work again once I've finished. Quite how they actually build these things at the factory is a mystery. It isn't something for the faint of heart to tackle, I'd reckon!

Interesting that you had cast metal seating mounts in your powered units; all mine, powered and non powered, have plastic seating units which, upon re-assembly, I cut back in the guard's area where it can't be seen. This makes it easier to refit and saves pulling on the wires going to the PCB.

[1018509]

That is interesting as al mine (4) have plastic seatig with metal weight underneath, i always found the trick is to remove the seating screws then seats and weights first, then the body eases off really easily by placing a very thin screwdriver between chassis and lower body, i actually prefer to use my fingernail to do this... Granted the pcb is tight but how you managed to break the pickups i have no idea as the wheel sets stay put

Oh and the end lights are moulded together so sit flush in the chassis as you put the body back on

I don't know how the pickup broke but it did and that led me to discover that there are metal and plastic weights and as I posted my unit now has one plastic and one metal weight and doesn't seem to mind.

In theory the light module sits flush but the wiring is quite stiff and dislodges the module easily - patience is the word here.

I don't understand how you get the weights out before removing the body as the clips holding the weights in have to be removed by unclipping from the side after the body is out of the way and if you have moved the body far enough to reveal the weight clips then it is off anyway and just needs the decoder PCB threading through to lift the body clear.

Anyway we have all proved that it can be done - it's just a pity that you can't buy just the gear wheels, motor and drive shafts separately.

[Vanders]

The different seat mouldings/castings is interesting. Perhaps Dapol have used different methods for different batches?

As for the light clusters, no matter what I did I couldn't get the things to stay put! I did consider adding a small dab of super-glue to hold them in place but then I worried that I wouldn't be able to get the body back on. Ho hum.

[1018509]

The different seat mouldings/castings is interesting. Perhaps Dapol have used different methods for different batches?

As for the light clusters, no matter what I did I couldn't get the things to stay put! I did consider adding a small dab of super-glue to hold them in place but then I worried that I wouldn't be able to get the body back on. Ho hum.

They do only go one way round and, on mine, the shaped end of the LED's fits into the holes in the cab but only if fitted the correct way round.

[1018509]

If you look in my first picture it clearly shows a lip on one side of the lights as you say which fits with the body moulding.....

I see it and agree there is a lip there but on neither of my units did it hold the lighting module firmly but - hey - we did it - which will encourage others to have a go and hopefully report back on here.