D869

Thanks Julia, I think it was your blog that first put the idea of a CNC Proxxon into my head. It's just taken me quite a few years to make it happen. I will probably keep the mf70 as is for a while. My tooling improvement 'to do' list is already long and distinguished.

I haven't posted much on my blog recently so thought I would try creating a workbench thread and see how that goes... so here goes... As some of you may know MinerChris is building a cameo layout based on Callington in Cornwall for the Diamond Jubilee challenge. I'm calling it 'Cameo Callington' (he isn't). He's making good progress but I can't see him having time to finish any appropriate steam locos before June so I thought I would take a break from Hayle North Quay and make a contribution. The original plan was to build an N Brass LSWR G6 kit and put it onto an 0-4-4 chassis to make an O2 class suitable for the layout. It hasn't quite worked out that way but there will still be some N Brass bits on the loco. For the last few weeks I've been concentrating on the chassis. Some words and pictures in somewhat backwards order... All put together. The bits. In spite of appearances here, the frames are 0.5mm phosphor bronze. I'm trying out the Dave Holland 'keeper' style of chassis and so far it's proving very handy during the mechanical fettling stage. The front spacer is solid brass to get the weight forward with a PCB insulating layer. The rear one is Tufnol. The main frames straight off the milling machine. I must thank Mr Brummitt for his kind advice on the subject of CNC converting the Proxxon. Some actual milling in progress. You may notice that this is not a chassis component. It didn't all go right - it took me some trial and error to get the milling parameters sorted. The top one has too much depth of cut. Bang up to date - after two rounds of fettling the bogie pivot and wheel arches, it finally managed to get through the horrible curves of South Yard's pointwork. The O2 will also be my first South Yard appropriate steam loco. The body is rather more advanced than shown here but I will save that for another posting when I get back onto that part of the build.

We mixed it with cheap instant coffee for the scenery on St Ruth. John's workshop smelled of cheap instant coffee for weeks afterwards.

Do you intend to get the foil off Cellotex somehow? I bought some foil free pinky/peach coloured stuff a fair few years back but I haven't seen it in the dreaded DIY sheds recently. Don't the manufacturers know that putting foil on their product makes it less suitable for model hills?

These look like the old Association compensated bogies. You had a bolster casting, etches for the 'structural' sideframes and multiple options for cosmetic cast outer sideframes. The rocking pivot was a ridge of whitemetal that you had to squash a bit once the etch had been fitted over it. I have a set under one of my siphons. The wheels would never stay put so eventually I modified them to be uncompensated which turned them into better behaved running gear. If you dig out a very old shop list then you can probably get a definite identification on the various sideframes in your stash.

Thanks Steve and Keith. Although I seem to have had brain fade when asking the question yesterday (I'd already read that it was using the milled chassis) I'm still curious about the oft quoted challenge with the front pair of driving axles on Castles and other big wheeled GW 4-6-0s. How does it all fit in? My understanding is that scale wheelbase, scale tread diameter, Association flanges and a motion bracket won't all fit - something has to give. Having looked closely at the real thing in the shed at Didcot there ain't a lot of room to spare in that area. Regards, Andy

Splendid stuff. Any idea what the situation is with the front two driving axles with regard to spacing when doing the 2FS conversion? ... did Mr Armes need to reduce the flanges or has Mr Farish spaced the axles a tad further apart than they strictly ought to be?

I did some with a single belt on my Unimat SL on the middle step of each pulley. Nominally 1600 RPM but it fluctuates with load. TBH I wouldn't get too hung up about speed as long as the thing is cutting nicely without undue noises, chatter, smoke etc. Just start with some wheels where you have a big surplus to practice on, in my case Farish coach wheels.

I recently built one of the SNCF steel minerals. The chassis for this allows other options to be built. I haven't looked in detail at whether it would work under the Association RCH body but it seems like it might. Has anyone else?

Thanks Pete. Good to see you too. No, I dont think that storage boxes count

Some photos from Tolworth. A good show, well attended and with plenty of quality layouts. This IoW layout, or rather three linked layouts was just across the road from us. Always a nice subject and nicely done. Harlyn Pier was our next door neighbour. A lovely layout with a T9 - one of my favourite locos. It moved off before I got a pic but the pannier was nice too.

You must be getting the hang of this exhibiting lark now Pete. Glad it went well.

Scoop... hmm... well, it's quite soon and we're taking St Ruth so just wondered if you would be along

There have probably been shows that have had us wanting to be climbing the walls but Leeds wasn't one of them. The sepia thing was unplanned... probably just the combination of the camera, layout lights and the hall lighting. Shall we see you at Tolworth Mr Pete?

Some photos from our trip to Leeds this weekend. A nice show with some good content and the food was good too so our thanks to the organising team and also the catering folks. It was perhaps inevitable that we were next to John Aldrick's lovely 2mm scale 'Ivybridge'. Couldn't see much ivy on it myself though. Looks like my flash triggered so this photo is hopeless - sorry... I rather liked this model of Outwell Village on the Wisbech and Upwell. I liked lots of other things too but didn't take many photos. Finally of course we had to drag Ivybridge into the 1960s... EDIT... another pic of Outwell. For some reason I thought this had come out badly when I looked at it last night but it looks OK to me today...

I tried a '1' in there but that didn't help. I also tried a CT in the Western and it ran just fine. The MC1 has a step upwards in throttle response around step 11 or 12. Maybe fixable but life's too short. The throttle response was smooth when I fitted the CT decoder. Thanks again for your help. The MC1 will be taking up residence in the bottom drawer along with the TCS board for the MP15. Regards, Andy

I think 25th class is a modern innovation for services which connect with Ryan Air.

I bought my bow pens direct from Haff (www.haff.de) a few years ago and have been happy with them. The ordering process was somewhat old fashioned (international bank transfer IIRC) and you may need a bit of google translate too but I think you can probably still buy pens from them should you wish. Regards, Andy

Thanks both. The photo sesh is done now but I'll have another play with the Western when I've got everything back in their proper places again. @Nigel I do get the feeling from other posts on here that the 20 quid Zimos are well regarded and plan to get hold of one to try out next time I am in the vicinity of a DCC trader's stand at a show. In the short term all of the decoders will be coming out of all of the the locos so it will be easy enough to try out a CT in the Western and find out whether it does better. I'm aware that the MC1's back EMF parameters can be tuned to the motor but the chip seems pretty basic in other ways so I'm not sure it's worth the effort. I do have some previous history that colours my views on this. I bought a TCS back emf decoder PCB that was purpose designed for the Atlas MP15 chassis in my class 22. I never could get on with driving it and my efforts to try to tune the CVs couldn't make it right. In the end I fitted a 6 pin socket and the CT does a really good job in that loco too. Regards, Andy

Thanks Nigel. So probably not original to the Dapol Western then. I'm somewhat comforted by that because although it does run adequately with this decoder I'd expect a good deal better out of the box from a factory fitted decoder. I do wonder whether the seller knew the decoder was in there or had acquired it like that. I dont think there was any mention of it having a decoder in the listing so it may be that he was trying to run it on DC. It certainly did run very badly indeed like that. I don't think I'll be spending much more time on this decoder. I might try one of the CTs in the loco once we are done photographing. Regards, Andy

Some time back I acquired a Dapol 'N' Western listed as a near non-runner via a certain auction site. On investigation I noticed a blue shrink wrapped thing in the DCC socket. Most of my running is on DC so I took it out, fitted a blanking plug and the loco ran just fine. I'm now getting ready for some photos and it would be nice to be able to be able to have the lights on with the loco stood still so I put the decoder back in and hooked it up to my NCE Powercab. Everything worked more or less as expected but the lights are too bright. The speed control is rather non-linear but I don't need it to move so I'm not bothered about that just now. Powercab reports the manufacturer and version as 141 and 081, which as far as I can gather means ThrottleUp(Soundtraxx) / OEM MC1. I have no idea if this came from Dapol or was fitted by a previous owner. I got hold of the manuals. These suggest that F7 will dim the lights by a fixed amount... but there is no noticeable dimming when I press '7' on the Powercab. https://www.soundtraxx.com/manuals/MC1 Users Guide.pdf https://www.soundtraxx.com/manuals/MC1 Tech Reference.pdf I did a CV reset by setting CV8 to 8 and powered the whole thing off and on just to be on the safe side. The manual says that the F7 behaviour is controlled by CV41 and its default value is 16. Mine was zero even after the CV reset. I tried 16 but that didn't help. I also tried setting CV38 to 128 (it was also zero) which should put dimming onto the F4 button so the function state is displayed on the Powercab LCD, but again no joy. All of the CV setting is done in Direct Mode which is supported according to the manual. I also checked CV49 which is something to do with selecting lighting effects. This was already set to 1 which I think is what it should be for dimming. There is a bunch of US lingo in the manual here about grade crossings and Rule 17 so I can't really figure out what this CV is supposed to be set to but 1 seems most likely. Does anyone have any idea where I might be going wrong? Have I identified the decoder correctly? Can it even do dimming? I did manage to sort out the dimming on my CT equipped Farish D800s but so far this blue shrink wrapped decoder has not been persuaded to dim its lights. Thanks in advance. Andy.

Thanks both for the advice. I will definitely avoid candles.

Excellent Mikkel. You should warn that Churchward chap to be more careful when wandering around on the track though. It could be the death of him.

Lovely job Ian. Decided not to stick with the NSLR livery then? A set of compasses with a bow pen on one arm and a blunt bit of brass rod in place of the sharp bit is worth a try for painting lines around corners. Probably best to practice on something else though. Regards, Andy

Fire retardant will be fine. I dont want to go over the top but I also dont want to inadvertently create a fire hazard. Looking at some of the stuff on the Interweb, the Cellotex and similar products have a good deal to say about fire resistance. The only specific thing I've found on fire behavior of the extruded polystyrene stuff says that it needs to be enclosed (something along those lines). No doubt there is better info out there and I'm still a good way off actually needing to make any hills - this was just a quick trawl.