beeman Posted January 22, 2011 Share Posted January 22, 2011 Thought I would display some of my pics for my VSU, to which I recently carried out some improvements. I 'upgraded' the electrical control system to a similar control as on my turntable. This made it simpler than having 16 relays, now 2 control & 2 interlock. The downside is , I have to remember whether it has to go up or down, previously it was automatic. The upside is, using the slotted opto switch for the stop position made it consistently more accurate. The pics show the adjustment mod with the threaded rods connecting the levels, these can be tweaked up/down for track vertical level alignment at both ends of the unit. I also decided to speed up the drive by increasing the diameter of the motor pulley, originally a belt drive from an old Concord electric lawnmower,using both toothed belt gears. This reduced the time for travel between levels to half the original, now around 70 secs. The track/scenery section at the front of the VSU can be slid out, only being held by a couple of screws, for clear access if required.This was built using rigid building insulation for the relief onto a wood and ply frame using impact adhesive, shaped roughly to profile, pasted with pva/polyfilla mix for surface finish before the scatter etc.. The gulley viaduct made from wood and card.The roughstone walling the firm foam found in tv packing, cut and 'picked' to suit.The distant backscene produced from digi photo,s taken locally then doctored on my PC for size and content, cut and pasted to produce what I feel is a satisfying distant view and continuation of the foreground. I call this my 'Country Run' bit of the layout. Must admit I spent ages with literally almost hundreds of sheets around the layout with this method to obtain what I visually wanted.This was also done using the commercially available backscenes, by copying and juggling them around to create a 'Flowing 'and plausible image in other areas. The distant country scene is pasted to a 4mm sheet of plywood which slots in between the country run bit and the VSU. as can be seen from the pics.The ply originally painted white then the blue for the sky after. The 'end' view shows the slotted opto switch which is the stop switch for the appropriate level, and the lens end bulb which projects onto the opto transistor is an optical interlock. These are fitted to each end and have led indicators on the control unit to show if any stock protrudes and also electrically inhibits the unit operating. This is necessary as the unit is behind the backscene. I also have angled mirrors so I can see the VSU at each end, and having run into the back of stock on the VSU fitted 4 laser detectors which work similar to the lens end system but over the length of the VSU for track occupancy. This is on the fixed approaches to the VSU so that it 'sees' the level in use. After first concocting the idea of a VSU some 30ish years back I have reached the point where I have 'loaded' it with some 23 complete loco and trains. The max length being a Pacific + 5x70ft. coaches, Hope this finds interest and hints for others. Beeman Link to post Share on other sites More sharing options...
Deev Posted January 22, 2011 Share Posted January 22, 2011 That is brilliant - a rolling stock jukebox!! How do you manage to get the track levels spot on to allow trains to roll on/off? Dave Link to post Share on other sites More sharing options...
RMweb Premium Kris Posted January 22, 2011 RMweb Premium Share Posted January 22, 2011 Very cunning. How quickly does it go up and down? Link to post Share on other sites More sharing options...
shortliner Posted January 22, 2011 Share Posted January 22, 2011 Brilliant work! Link to post Share on other sites More sharing options...
beeman Posted January 22, 2011 Author Share Posted January 22, 2011 Thought I would direct anyone interested to my post on the old site describing the VSU rather than repeating myself, or would be happy to respond to any specific queries. My linkThis was before any scenery was attempted, and the old control system as can be seen, now much rationalised.Beeman As an afterthought I will include the link to the post I did some time ago on my turntable. I used almost the same circuit for the VSU, thus making it much simpler and the 'stopping' more accurate. Virtually the circuit is the same except for the inclusion of two miniature relays which interupt the start button line should there be any stock interrupting the sensors.This as said earlier prevents the VSU from operating. There are micro switches, one top, one bottom, that are in the motor supply lead so if in the event a relay contact became 'welded' together the motor is switched off at the ends of travel, as an 'ultimate limit stop switch'. Beeman.My link Link to post Share on other sites More sharing options...
Brush47337 Posted January 22, 2011 Share Posted January 22, 2011 You deserve a coconut for that - fantastic. Any chance of a wee video to show it in operation....? Please Link to post Share on other sites More sharing options...
alangdance Posted January 22, 2011 Share Posted January 22, 2011 Thanks for the info regarding your VSU. I am just about to build mine. You have given me some answersto some problems that I was excepting to get. At the moment mine will be a bit bigger than yours using door runners for the movement. It will be manual control for now. I have being looking into auto operation as well. I was thinking of using 2 stepper motors and a small PLC to control the selection of track and stopping position. Not to sure how to hook up the motor to the VSU at the moment, will need more research into this. Thanks again for the pics and write up. Any comments. Regards Alan Link to post Share on other sites More sharing options...
beeman Posted January 22, 2011 Author Share Posted January 22, 2011 Hi Alangdance, be interested to see how others would design a VSU, the suggestion of the door runners interests me., are these for positioning the unit ?, how are you going to raise/lower. Think it was Jan.2010 in one of the Model mags an article was published of a similar idea that carried, if my memory is correct, 60 trains, Gord help the weight of that lot considering that the thing was lifted by ONE central screw thread, which I think was 12mm with a single nut fitted to the moving frame. Sorry to suggest but this to me was engineering lunacy as to the construction strength, it certainly would be damage wise if it collapsed.. It appeared the designer/maker said he had problems and attempted to fit some sort of counterweight. I would give 10/10 for effort but 0/10 for its practicality, having bu*****d around with mine for many years although intermittently. Finding faults and improving/correcting when required. One of the latter problems when fitting into its present location being movement, which many complain about re baseboards on the move. I built a dedicated train shed in the garden, block built/rendered and lined throughout with chipboard flooring. Still found very slight movement due to suppose temp/humidity, this affecting alignment, my VSU being screwed thro to the blocks. Therefore the latest modifications being required, and I reckon about the ultimate. Anyway, Good Luck and keep us informed of your progress/ides Beeman. Link to post Share on other sites More sharing options...
alangdance Posted January 22, 2011 Share Posted January 22, 2011 HI Beeman My throughts were to use 2 stepper motors ( if money was no object I would use a servo motor instead) link together driving a couple of lead screws, this would be to even out the weight or maybe connect the door runner somehow to some spockets and timing belts to drive the VSU. The use of steppers is for getting a much accurate adjustment than with a normal motor( 1.8mm on full step or 0.9mm on half step)than using sensors to stop the VSU in its correct position. The control would be using a PLC ( maybe a logo or similar). I have not yet looked that close at the auto side yet only played around with a few ideas in my head. 1st is to get the VSU working manually then I will look into auto side after that. My VSU will control 32 trains (I hope) but may change if this works out to be to heavy to lift. Regards Alan Link to post Share on other sites More sharing options...
alangdance Posted January 23, 2011 Share Posted January 23, 2011 HI Beeman A quick question for you what type of motor are you using, whats the voltsge,amps and watts. Alan Link to post Share on other sites More sharing options...
beeman Posted January 23, 2011 Author Share Posted January 23, 2011 HI Beeman A quick question for you what type of motor are you using, whats the voltsge,amps and watts. Alan The motor I used was a 24vdc windscreen wiper motor, came off mobile plant. not sure of rating, about 75 x 90 mm no gearbox. can be seen in pics in the link to old post. I would imagine that the 2 worm drive gearboxes, again wiper unit + the actual lifting screws [car jacks] give the unit a high mechanical advantage. when I fist made it many years back I sat on it to 'test', and it would lift me then, bit older and rounder now though, so I will stick with original testing.The actual stopping and description is similar to my turntable posts [link]. this using 1.5mm wire thro the opto switches, Allowing for differential depending on travel direction the actual cut off is less than .5mm, so very adequate. I find that the whole thing will move slightly due to expansion/contraction than the stopping accuracy. This is perhaps more accurate than what one could achieve with stepper motors. As one site reports these can 'hunt' around the stop position, and are far more complicated in circuitry. .Any movement, albeit minimal, of the unit as with layout baseboards is a problem I have to accept, the reason why the last 60mm of the tracks are fixed with a washer /screw, both the approach/exits and the levels of the VSU. Beeman. Link to post Share on other sites More sharing options...
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