D869

Thanks - looks good. I'm assuming your Cellotex had foil on it? Having said that I'd prefer foil free stuff I'm also thinking that anything polystyrene based will do bad things in a fire. None of us want a fire but it would be nice to know that I'm not creating hills stuffed with flammable material that will create poisonous fumes if the worst happens. Regards, Andy

Thanks for the info - will save me a good deal of googling time. The pink extruded stuff sounds like what we used last time around. I definitely want to start with something where I dont need to remove foil or whatever other facing if possible. The baseboard structure will be the more traditional plywood. Regards, Andy

Thanks for the info Don. I've used the more dense builder's rigid insulation foam on South Yard and St Ruth for making big volumes of 'hill'. I'm not sure exactly what the technical term for this material is. The stuff I've seen more recently has foil on both sides so I have been wondering what I will use for the new layout - maybe the non foiled stuff is still around and maybe it isn't. I haven't really looked very hard yet. It wont be expanded polystyrene though - I agree it's 'orrible stuff when you start cutting it. The ground at the rear of the quay will need something fairly substantial though. It's neither low nor subtle. Regards, Andy

Cheers Don. I've always chucked any corrugated cardboard in the bin having never found a use for it but maybe I'll give that a try. Just put a load of it out for the recycling binman tonight as it happens. I'm sure more will be along quite soon though. Regards, Andy

Hi Ian, Glad to hear that it's not just me that struggles with this. Your diagram is clearly the answer - just build that Seriously, I think it is tricky - I think we are conditioned to dismiss things as 'flat' but we need to change our perception. I found that cycling on roads that I'd previously considered 'level' when out driving changed my perception of them pretty quickly. The trouble is that even when we know that there are subtle variations in level, it's still difficult to work them out by looking at photos. Going to the real place can help... but only if the ground levels haven't changed (which in the case of Hayle they have... a lot). Mucking about with bits of cerial box and clay certainly helped me to get to a conclusion that I was happy with. I was wondering while doing this whether clay would be usable as a ground making material for real. I've now decided that the answer is 'no'. My clay is dry in places now but the main issue is shrinkage - the paper templates were wrinkled where they had been pulled around by the shrinking clay. A quick slice with a sharp knife around the edges of the clay to separate it from the paper has allowed me to straighten the paper out again. I will stick to the more usual things like Sculptamold for the real layout. Regards, Andy

As we all know, the Earth is anything but flat but a flat earth is quite a common sight on our models. Now it's pretty obvious that Hayle North Quay has some high ground at the back and a quay edge at the front, but is that the whole story? Well, no... A couple of examples from my visit in 2010 (the place has been completely rebuilt since then to provide flood defences). I'm not sure what this building used to be, possibly stables for the Steam Packet hotel or possibly something else. In theory this is on the flat part of the quay, but look at the ground line. The wagon weighbridge (in its original position) - pretty flat here but look in the distance - the road (and inset rail track) are climbing up to enter the former Octel bromine works site. In the 1950s this gradient was used for gravity shunting. The problem (for me) is knowing how much level change is enough. While puzzling over this I looked again at my many photos and found a little corner of a photo of one of the other quays which showed North Quay in a helpful way... So roughly speaking, the rear of the 'flat' part of the quay is higher than the quay edge by about the height of a car (A40?). I guesstimate about 5 feet. The bigger conundrum for me was to figure out how a small patch of ground in front of the Octel works 'fits together' from a height perspective. These level changes are less subtle but I found them quite difficult to figure out. A couple of snippets from 'Britain From Above'... Towards the rear of this little scene we have the rail line up to the Octel works... which is uphill but only up a railway kind of hill plus a non-too-steep ramp from the road back down to quay level at the end of the detached cottage. All quite subtle but on the other hand the two semi detached cottages have a retaining wall at one end which is is almost a full storey high and has earth to the top of it on one side and the ground level is similarly high where it meets the inclined front wall of the detached cottage. Now maybe it's just me but I couldn't make all of this fit together in my head... and also factor in some selective compression. In the end I decided that building a scenic mockup of the patch of ground and the incline to the Octel works was the only way to figure it all out. The mockup sits on an old piece of laminate flooring and is all done with cheap card, cerial boxes and Templot printouts. I didn't have any suitable 'ground' material to hand so I took a trip down to my local Hobbycraft and a bag of air drying clay was about the cheapest thing that seemed like it would do the job. It was quite fun to do - sticking extra bits on here and there or carving bits off and easily smoothed over with a dampened finger, screwdriver blade or an old butter knife. Have I got it right? I don't know but it doesn't look too far from what I see in the Aerofilms photos. What still puzzles me a bit is why they didn't just dig more of this ground out instead of building retaining walls and leaving it piled up against their back walls to cause damp. I have a theory but will leave this as an exercise for the reader. Wot, no tractor? Actually the tractor is part of this story because it will hopefully drive along the road and negotiate that ramp in order to get to the other end of its train. Using the info from the scenery mockup, I worked out how much extra 'padding' the ramp would need and added a functional but rather less scenic balsa wood ramp to the tractor test bed... I'm not sure how long the clay will take to air dry - it's had several hours so far and isn't showing any signs.

Cheers Laurie. Good to see you and glad you had fun on the day. All grommet/strain relief suggestions will be stored away for the day when this particular job comes off the back burner so thanks for that. Before that day there are more important things like wood to cut and so on. I was thinking of some flippant comment about our respective mental states but decided that it might be best left as an exercise for the reader.

It was good to see you and Parkend at Tutbury Steve and glad that the other show went well. I guess you have seen the photos on the Tutbury thread that I and others have posted. I'm not sure what to make of automating a layout to be in sync with the real thing in Japan. It's certainly original but I can't see it catching on for folks modelling freight lines with just one train per day Regards, Andy

I have in mind something similar involving making something along the lines of a stepped washer on the lathe and using it with a flexible grommet/strain relief sleeve unless I can find something better ready made. It's not very high on the 'to do' list though.

Hi Ian, I think that the thin metal of the malt whisky tin is capable of slicing through a grommet when used on a handheld controller like this so it needs something to protect the grommet from the metal. I already have some things like these in my stash... https://uk.farnell.com/hummel/lcp07b/cable-gland-polyamide-6-5mm/dp/2887516 These should prevent the metal from causing damage but they lack any strain relief at the point where the cable exits the gland so I dont think they are ideal either. Something that has both a hard plastic sleeve through the hole and also a flexible strain relief sleeve on the outside end would be ideal but the stuff I've found so far has one or the other, not both. If only the whisky people had foreseen the high probability that their packaging would find a new use as an electronic project enclosure, honestly...

Good to see you too Pete (plus Kyle, Meeth, Exeter and Loch Awe) and sorry we didn't have more time to catch up. Yes, the enclosure I've 'upcycled' to house the tractor controls has attracted some favourable comments. A sort of new take on John Greenwood's 'beer can' controller. It was originally temporary but it is quite a nice size so I think I'll probably keep it as it is - I just need to figure out a more long term arrangement for getting the cable out without the tin slicing through the wires. Regards, Andy

As you might have seen on one of 2mm threads, the tractor and its test bed put in an appearance at the Tutbury gathering yesterday. Several folks had a try at tractor driving and several politely declined. Apart from hopefully being entertaining for the budding driver it was interesting for me to see what happens with someone else at the wheel. Full marks to Laurie Adams for being the only person to attempt and complete the full tractor shunting challenge (swap an incoming full tank with an outgoing empty one). So apart from having a good day out and a deadline to actually make me get things done, what did we learn about using the tractor under the gaze of the public ? People unfamiliar with the tractor seem to start off by driving very slowly. This is understandable but I'm not sure it's a good strategy because as well as the tractor moving forward more slowly the response to the steering also takes longer and the driver has time to over correct. People have different 'muscle memory' of what a rotary control should do. It is a bit confusing for a long time model railwayist to be presented with a handset on which the rotary control is a 'steering wheel'. Figuring out which is left and right can also be a challenge when the tractor is pointing in different directions (not surprisingly, radio control modellers tend to be better at this). Things get more fun when you then hand them the other controller so that they can do some shunting with a loco. I don't think there is anything to do here other than to watch knowingly while they get used to it although using a Powercab DCC controller for the trains might be easier on the brain. The test bed was kitted out with more dummy scenery and buildings than last time so there were more opportunities to collide with the landscape. Not unexpected but if the driver keeps the throttle open then the tractor will part company with the magnets underneath. After this happens it is tricky to 'find' the magnets again... the extra stuff on top acting as a disincentive to lifting the lid to figure out where the magnets are. This is a good lesson because it won't be possible to lift the lid when the tractor is installed on the layout proper. I have some ideas about how to make it easier to get out of this pickle. Sometimes the control system's centre position drifts over time. This is probably because friction or collisions up top are creating more resistance than the steppers can handle and they 'lose steps'. This is a job for some more Arduino programming - at the moment it only 'finds' the centre when it starts up but with some work it can also correct for lost steps while it is running. I did managed to get the tractor stuck 'in a corner' once between the limit of lengthways and widthways travel so need to give a bit more thought to the way that the limits work to prevent that embarrassing situation. Luckily nobody was looking. More visual feedback (probably some LEDs) is needed when the magnets are moving without anything visible 'up top' before and after the gravity shunt. On the whole it kept running for the whole day with very few unscheduled stops to lift the lid and sort things out manually. As far as I know it only went completely pear shaped once when the carriage swing arm somehow managed to swing a long way past what should be its 60 degree limit. I thnk I was watching Parkend when it happened so I'm not sure how it got into that state but the bigger concern is that even with a 'standard IT fix' (turn it off and on again) the thing couldn't sort itself out without extra manual help, so some more work needed there.

(apologies for inadvertently putting this in the PSJ thread at the first attempt) Some photos from my camera. I will plead the same excuse as others for not providing photographic coverage of the whole lot. Steve Nicholls' exquisite 'Parkend' - I've been hoping to see this for a while so was glad when I heard that Steve had been roped in for Tutbury Glencruitten airship base - an interesting prototype - certainly a new one on me. Mr 'Shunting Tractor' Adams was snapped in the act of having a play with the Hayle tractor test bed. I really should have cleaned up my cake oriented detritus before getting the camera out though.

Oops - sorry - posted my photos in the wrong thread - the perils of having two windows open.

Err... the money shot? All being well the L61 shunting tractor will be there along with its test bed and some wagons to push around tomorrow. Looking forward to a nice day out.

Err... jealous! Looking forward to seeing you at Tutbury on Saturday. Regards Andy.

Looks like Padstow station building to me. What are you using for the stonework please Jerry? How are you doing the flashing? Regards, Andy

Cheers Pete. Likewise for Kyle. Should be a good day out I reckon.

I've volunteered to take the tractor test bed to the Tutbury gathering next month so I've been doing some more work on it ahead of that. All of the work so far is 'below stairs' so visitors may not see much visible difference from it's state last year at Chelford but in fact quite a lot has changed. The first big change is that the curtain track has now been relaid to run dead straight instead of following the line of the Esso siding. This makes manual steering more predictable - previously it was a bit tricky to drive when the carriage was on the curve, so trying to steer the tractor along the straight road of the Esso siding turnout was not easy. Old... New... Second I've made the swing arm about 20mm longer and added a new gear into the train. This means that the magnet can reach 20mm further out on either side of the centre line. Several of the el cheapo moulded chinese gears have been replaced with machined ones from HPC. A couple of cheapo ones remain where I still need thin gears. Thirdly there is a little sensor (called a slotted optical switch) part way along. The carriage has a rectangle of black plastikard that passes through the slot, breaking the light beam. This allows the Arduino to 'know' how far along the track the carriage is. So why bother when it was working OK anyway? Well the other big item on the 'to do' list for the mockup was to deal with the gravity shunting that was used in the 1950s to gravitate oil tanks from the bromine works gate back onto the road outside the Esso depot. My original plan was to build a separate contraption with an electromagnet moving along another track. I did some experiments with small electromagnets and found that anything small enough to fit just wasn't strong enough to do the job. Plan B was to have a rare earth magnet mounted on a servo so that it could be either engaged or not with the tank to be moved. After sketching several ideas which all looked like a lot of work I started wondering if I could avoid the job entirely and do the gravity shunt using the tractor drive. To cut a long story short I found that I could... but the tractor drive would need more 'reach' and the Arduino (the brains of the operation) would need to know exactly where the magnets were instead of just knowing the general direction in which they were pointing. The Arduino software naturally needed a whole lot of work to make it do new things. The final piece of work has been to replace all of the curtain track mountings. They had been done fairly quickly (i.e. badly) by just screwing down into bits of strip wood glued to the cross members along with Blu Tack and bits of wood or card to pack things to vaguely the right height. This was OK to get things working but on the real layout they wont be accessible from above so I needed to design some new mountings that can be adjusted and removed from below. The new ones use Tufnol blocks drilled and tapped to take machine screws and an aluminium angle cross member that is removeable from below. Finally while the thing was turned over I took a picture of the carriage from underneath from where you can see the two stepper motors and the bits that keep it on the curtain track.

Hmm... so is the 119 quids quoted here not an outright purchase price? The US site also lists a more basic 'Designer' version for 60 dollars (plus tax) but this doesn't seem to be on the UK site. Regards, Andy

Thanks Mikkel. And thanks for keeping us posted on matters in your neck of the woods.

Thanks Mike. It sounds like the TurboCAD way of creating fills is similar to QCAD (i.e. select the bounding outline) rather than DraftSight. I guess I just need to bite the bullet and change the way I draw my half etch outlines. I managed to get the red fills sorted in my new chassis deck drawing (which is a more 'normal' 10ft wheelbase 17'6 over headstocks tank chassis). The red lines are all closed polygons and are drawn for just one quarter of the chassis and look like this... I was lazy and used overlapping rectangles where the chassis members cross. These were filled a polygon at a time and then just the fills were mirrored on 2 axes to do the other three quarters of the chassis...

I've been continuing my work with QCAD as and when the opportunity arises. I don't want this to become a QCAD specific discussion but it does (I hope) highlight the differences that can arise between different tools in the same part of the market. Most things in QCAD are bit different but it doesn't take long to get used to a new way. On the other hand I think that the way fills are drawn is quite different and will need me change the way that I draw the outlines. Here is a coloured in example - the deck from a Pickering 14T chlorine tank... In DraftSight I drew the overall metal outline first... and then I drew the extra lines to divide off the half etched areas (the white outline is switched off for this screen grab)... From what I've seen of QCAD so far this needs a different approach. In DraftSight the fills are done by turning on the required outline layers and then clicking on a point inside the area to be filled - rather like 'flood fill' in a bitmap drawing tool. In QCAD the fills are drawn by selecting the outlines bordering the area and then asking QCAD to fill the selected outline... fine here for the overall metal fill but not fine for the red half etches because at the moment there is no easy way to select the outline of just the half etch area for the red half etch. I think it needs a dedicated outline around each half etched area so parts of the white border need to be copied into the half etch border layers. It will probably be quicker if I draw the half etch outlines as a bunch of separate polygons which overlap each other rather than trying to draw the whole complex half etched area as a single outline. None of this is insurmountable but it's all work to do when changing from DS to QCAD. Perhaps one of the TurboCAD users can tell us whether it needs the user to draw fills in a manner similar to DS, QCAD or has another way to do it?

Quite a long journey back from Cumbria last night so the blog posting had to wait until today. Some photos from our trip to Maryport - a general model show spread across two decent sized sports halls and with some very good layout content. It definitely deserved to be better attended than it was but we still had some very knowledgable punters come and talk to us. Our train set Whithorn - apparently Maryport (across the Solway Firth) is the backscene for this. Calderwood - nice pre-group modelling but a tricky one to photograph Maidenhaiste - made quite big too! This class 37 on Crimson Road has seen better days 'Bobbin Mill Halt' 'Bobbin Mill' has a nice D800 - a bit big for our needs though.

Consider your lurking at an end I semi agree with you... if the etch is heavily text based or perhaps for something like decorative ironwork then a vector graphics package will be better suited to the job. I've done artwork both ways and I'm far more comfortable doing 'engineering' artwork (wagon chassis and so on) in CAD - it tends to have more advanced object snapping features and the ability to copy or move objects through a specified distance that my vector graphics package (Inkscape) lacks. I did put some 'engineering ' stuff onto my Inkscape artwork but I was quite glad to get back to CAD for the next lot. I'm sure that more expensive vector packages may have a better features.