Dave Holt

Hi Robin. My arm is progressing slowly, thanks. I have a little less discomfort and slightly more movement in the shoulder, but I think it's going to take quite a while. The A&E doctor said 5 to 6 weeks. However, I think that is just the initial period for the bones to start to knit together. I have a physiotherapy appointment a week tomorrow, so I might have a better idea after that. The other thing I forgot to comment on is just how well the Peco EM buffer stops fit onto P4 track. Amazing! Dave.

I believe the idea was to allow easy reversal of the bogies to protect AJ couplings from transport damage. You just pulled the bogies off and clipped them back with the couplings pointing in to the centre of the coach, safe from harm. Dave.

Those flares look very neat indeed. You're obviously a dab hand with a small hammer - a panel beater in a previous life, perhaps? Dave.

Yes, Robin, the power boxes do look very neat indeed. The storage sidings look to have come on quite a bit, too. Very impressive. Happy New Year and good modelling in 2019. Dave.

Yes indeed. Your rate of progress is excellent compared with my glacial efforts and the results are looking very convincing. I'm finding it all most inspiring. Looking forward, very much, to further installments. Best wishes for 2019. Dave.

Yes, congratulations on what looks like a very satisfactory set of valve gear. I'm glad to hear that it really did prove easier than you anticipated and that you are now raring to go at another example. It may be the angle of the photo, but it looks like a tweak of the return crank might be necessary to get it to tighten up at the correct angle. I find this to be one of the trickier aspects that I still don't get right every time [i over-did things on my BR Std 2 tank and so one of the cranks relies on cured Loctite to hold it just so]. I'm particularly looking forward to seeing further progress to complete the chassis and to see what improvements you make to the body, so I can steal your ideas! Haven't got on to that with mine, yet. I agree that the Kemilway Walschaert's valve gear was extremely realistic and way ahead of other makes, at the time, although I suspect some of the more recent, top end, kits [brassmasters, Finney and, especially, Dave Bradwell - although none of them do prototypes that suit Cheddar!] are even better. It used multi layers to provide proper forked joints and I've seen a couple of built up examples of the 3MT 2-6-2 tank, in P4, which look excellent [most recently on "Sidmouth"]. However, if it is similar to their Standard Class 4, 2-6-0 and Bulleid light pacific chassis, it incorporated a very odd arrangement for the compensation by mounting the non-driven axles on a separate sort of bogie rather than using conventional axle boxes and horn guides. I found that, despite keeping running clearance to a minimum, it still allowed the leading axles to waggle back and forth, effectively altering the coupled wheel base. I attempted to eliminate this unwanted play by tying it all together with springy phosphor bronze strips, but it would be better to replace the whole arrangement with a conventional set up. Best wishes for the layout and future loco projects, Dave.

Shouldn't worry too much about the exact arch form for the bridge, it looks to replicate the prototype very well indeed. I must say, you modified cassette alignment arrangement looks very nifty and a significant improvement on the previous version. Did you need to make a number of trial units to get a good, firm fit between the two sections of the joint. Presumably, fine adjustments are possible with laser cutting? Dave.

Work steadily and methodically, remember to make two handed sets[!], follow the guidelines and I bet you'll do just fine and wonder why you were so apprehensive. Do follow the Comet instructions and have a few good photos of the real thing, so you know what you are supposed to be representing - I've seen two models recently with the curved expansion links fitted back-to-front. All the locos I've built except the recent Caprotti Black 5 have outside valve gear, so I must have done a first one and survived. Dave.

Jeff. It's coming along nicely. For piston rods, I find nickel-silver rod [0,8 to 1 mm diameter, to suit the prototype] represents hem well. I turn down the wire to about 0,5 mm for the last 1 mm or so. This way, you only have to drill a small hole in the front of the cross head [think you called it the slider?] casting. Not having a lathe, I do the tuning by holding the n/s wire in a pin chuck and using a combined rubbing and twisting action along a fine file. As long as you progressively turn the pin chuck as you file, you end up with an acceptably round and central reduced shank, which can be carefully soldered [but could be glued] to the cross head. In my locos, the slide bars are far enough apart to do this assembly with the parts in situ, to ensure proper alignment. However, on your model, it looks like you would have to do it as a separate item, aligned by eye, and then carefully adjusted by trial fits until satisfied that a smooth fit has been achieved. Dave.

Nice to see someone else having a go at one of these [in P4]. I'm sure you will be able to sort out the ride height by judicious filing/cutting. It's so long ago that I started mine, I can't remember what the issues were, I just know it sits right now [bottom of the tanks level and correct height above rail]. It looks like you have a different rear body mounting arrangement to me. On mine, there were two mounting pillars inside the bunker moulding, so I fixed two pieces of brass angle on the outside of the frames, set at the correct height, to pick up these original Bachmann mountings. To suit my own preferences, I purchased a second valve gear etch, which allowed me to double up on some of the valve gear items. For most valve gear pivots [except forked joints], I tend to use brass lace makers pins with their heads reduced in both diameter and thickness [twirl against a file whilst held in a pin chuck]. Make the pin a tighter fit in the rear layer and use a layer of [possibly oiled] cigarette paper between the rod to prevent soldering the whole thing solid. Good luck with it and keep us updated with progress. Dave.

Thanks for the kind comments. Recovery is probably just a matter of time. Regarding the crewing issue, moveable crew sounds a bit too complicated, even if technically possible. I think I'll go for the two on the loco and one in the coach suggestion. Dave.

I think you've got a bit of time to think about this aspect. There's the minor issue of building the layout first. Dave.

Unfortunately, I will be taking a forced break from modelling for a few weeks, having broken my right arm, just below the shoulder joint, when I tripped and fell heavily on concrete, on Tuesday. Never to be recommended, but this does seam to be a particularly bad time to be incapacitated, what with the build up to Christmas and New Year. Prior to my accident, I had progressed the Std 2 tank by fitting the cab glazing and adding coal to the bunker and had started to paint the [Modelu] crew members. Here's a dilemma with a push-pull fitted loco. Does one have both driver and fireman in the cab or just the fireman? It can only be right for one direction of travel, unless someone knows how to make the drive pop up/disappear dependent on whether pulling or pushing. The same issue applies to the driving trailer of the train. Here are a couple of rather poor quality photos of the loco, one including part of a typical Delph push-pull train from the mid 1950's - ex-LNWR motor coaches in LMS or BR livery. Dave.

And a bit of a contrast to your previous build! Dave.

Very neat attention to detail, especially the push-pull gear. Super modelling. Look forward to following further progress. Dave.

Mike, Thanks for your kind comments on the Std 2 tank. I've started the Rumney chassis for the welded 16 tonner (D109, with Morton brake gear). So far I've made up and fitted the chassis top and the W iron part and, as you and John say, it all goes together very nicely indeed. Dave.

John, Yes, thanks. I wasn't worried about the assembly of the Rumney kit, but rather my lack of prototype knowledge regarding axleboxes, holes in W irons, builders plates, etc., for which the kits give options.. No doubt when its done, someone will point out that the particular wagon number didn't have some aspect I've built in. Dave.

I left the Class 40 with the bogies wheeled and the loco test pushed through some of the yard throat point work. Since then, pick-ups have been added and the loco rendered operational, though not without some trials and tribulations. My clever plan for the pick-ups proved a bit too clever for its own good. The mounting bus-bars were just fine as were the simple phosphor-bronze wire pick-ups for the inner wheel sets but those for the outer driven axles gave lots of problems with shorting out on the bogie mounting units. This resulted in a brief period of near despair when I thought I had blown the DCC chip or the control unit or both as on first power application the whole thing went completely dead after moving only a few millimetres and the hand set had a flashing display I just couldn't get rid of. Perhaps old bods like me just shouldn't try to mess with new technology. In the end, it turned out I had simply failed to press the reset but had tried unplugging, cancelling and all sorts of futile actions. The solution involved moving the pick-ups to the outer side of the wheels and re-bending them to try to clear the mountings at the extremes of the suspension movement. In the end, I also had to file some mouse-hole shaped cut outs in the mounting stiffeners on the under side. This appears to have finally solved the shorting problems and I now have a fully functioning chassis - at least up and down my short, straight, test track. I'm intending to give it a longer running in session on the North London Group circular test track next Monday. In the mean time, I also attached the Bachmann cosmetic bogie frames. making quite an improvement to the appearance of the loco and providing mounting points for the Alex Jackson coupling hooks. Still got most of the piping and other details recovered from the Lima project to fit to the new frames. The Bachmann moulded plastic air pipes on the bogie front plates have proved particularly fragile and vulnerable to handling damage and will be replaced by the brass wire versions I made for the Lima. Since sorting the electrical problems, I have to confess to the rather childish pleasure of running the sound, repeatedly going through the start-up sequence and then leaving the loco idling for ages with that characteristic warbling whistle, so redolent of these locos. I imagine the sound will be switched off after a few laps of the test track, to avoid me being pummeled to a pulp by angry NLG members, driven to distraction! Here is the loco in its current state: I've just been advised that the painting and weathering of my BR Standard Class 2 tank is now finished, ready for collection tomorrow. David Clarke has sent some photos showing the result. I have to fit the windows, coal and a crew to finish it off. It looks like some minor adjustments to the return crank positions might also be required, although it might just be the angle of the photos and crank positions. We'll see: Thought I might have a go at the Rumney Models sprung chassis for a couple of BR 16T mineral wagons I've had for a while. Just preparing to start shows just how little I know about wagons. Help! They look trickier than locos. Dave.

....or unusually long arms!

I'm fairly sure that DC vs DCC does not affect the pick-up arrangements on a model loco. After all, it's just a stream of electrons being transmitted from the track, through the wheel rims to something (the motor or input side of a chip) on the loco via the pick-ups. Many commercial models are supplies "DCC ready" which means they are analogue but can be converted easily to DCC by replacing a blanking plug on a circuit board with a DCC chip. There is no need to make any changes to the pick-ups. Dave.

It's certainly coming along well. Perhaps you could break up the large strawberry patch by having a few workers weeding or such? I must say, the track divergence and board width at the near end of the last photo do look rather wide. Will you have access to both sides when operating, in case of derailments (which, of course, never actually happen on our P4 layouts) or the need for a gentle prod of a recalcitrant loco? Dave.

Ray. The picture look just fine on my computer. The chassis looks to be coming along very nicely. What is the purpose of the three small, fold-out tabs (the upper one at about 45 degrees) between the front and centre driving axles? Dave.

I agree. Dave's chassis is a thing of beauty. I also have one in my "to do" store. Dave.

Gibson wheels. Apparently, they have too small a crank throw for the 9F, being based on the Class 2 wheel but I lived with that. I don't think there's currently a better wheel available (don't know anything about Markits). Barrow Road, of this site, has had some P4 wheels made by machining the Bachmann wheel centres and fitting new tyres. Only viable if you have the requisite tools and skill. Dave.

I built one in P4 and used a mix of compensation and springs. The front truck and centre driving axle are both sprung using coil springs. The first and second drivers have a singe, central beam and the rear two drivers have twin beams. Track holding is superb and the ride very smooth and steady, having no fixed axle. The only thing I would change is to limit the downward movement of the sprung centre axle so it cannot drop below rail head. I have experienced odd occasions when the flangeless wheels have dropped off the rail on too sharp a curve and dropped down, jamming the whole thing up! I drove the 4th axle with a High Level gearbox, motor vertical in the firebox. The frames and coupling rods were from Alan Gibson - correct wheel spacing - the rods having joints at all the intermediate wheels. Because of the deeper flanges in EM, I think you need to stick to the Comet bits, which have a stretched wheel base so the flanges don't overlap. If you purchase and extra valve gear set, you can modify the coupling rods to give the required articulation for a fully compensated chassis. Good luck with it. Dave.