walkingthedog Posted February 26, 2020 Share Posted February 26, 2020 Metcalfe kits do seem to make you start building as soon as you open the packet. Ooh I wonder how that goes together..............before you know it you are surrounded by glue and bulldog clips. Link to comment Share on other sites More sharing options...
96RAF Posted March 4, 2020 Author Share Posted March 4, 2020 Track bus wiring.I decided to try a new method of bus wiring, basically accessible from above board using plug in choc-blocks.Each heavy bus wire is daisy chained around the circuit linked by plug in choc-blocks. Each choc-block half is link wired to make every terminal common to the bus.The other plug in half will be wired to each track piece per normal practice.Once all the track wiring is complete the choc-blocks will be assembled, checked for cross circuits and pushed out of site under the elevated sections. From the controller.../media/tinymce_upload/ad09bab67e51eb1b4ddde31bd927a27e.jpg To the first break out connections...the wood block is to ensure no shorts between the bus wires./media/tinymce_upload/ca7ba1a3d24ee0aa1905a24b7b0343ec.JPG Via several more to the last connection where the terminator will be fitted.../media/tinymce_upload/ff7b2d25db049280c45d53c0be1c3a71.JPG Once the bus is installed and rung out test locos will be run as far as the isolated sections at each end will allow. Link to comment Share on other sites More sharing options...
96RAF Posted March 7, 2020 Author Share Posted March 7, 2020 Changed my mind.Going to use these instead of the choc-blocks./media/tinymce_upload/b520557b43463d934859a7d6809c9e92.jpg Same idea but a bit more professional and neater. Link to comment Share on other sites More sharing options...
96RAF Posted March 11, 2020 Author Share Posted March 11, 2020 A small problem has arisen during power bus wiring.I have a 9V battery connected to a buzzer which I clip across the dead power bus, such that if I cross a wire when installing the droppers then it tells me there is a short. I am about half way through wiring the first terminal board before I find and connect the buzzer which imeediately yelps at me. I have checked the track plan for hidden reverse loops and can't see any and I have checked each dropper is the right colour and attached to the correct bus on the terminal board, so why is the alarm going off. The track has one siding that has an led buffer stop already installed so I lifted that track piece and still the alarm wails. I can only think that because the terminal board (picture in previous post) has a power indicator light (which glows green if + and - are correct or red if + and - are reversed or orange if DCC is applied) this could be the cause of the alarm going off. The indicator is simply a resistor in series with a bi--colour led wired in parallel across the + and - busses on the board. I have no desire to disconnect every dropper just to prove the point. Wiring droppers is brain numbing to start with without doing it twice. Plan A - connect buzzer across an isolated terminal board. Does it wail or not. I think it will.Plan B - connect a Select with a 1-amp PSU and see if it OLs. I don't think it will. If Plan A is true then how do I continue wiring droppers secure in the knowledge I haven't crossed one. Track plan - no reverse loops that I can see./media/tinymce_upload/aabc918aa1c36a83b7219d78fef94bc6.JPG Thanks for any helpfull suggestions. Link to comment Share on other sites More sharing options...
Rog RJ Posted March 11, 2020 Share Posted March 11, 2020 Cut or desolder the resistor in series with the LED on the distribution board to prove if that is causing the problem. Link to comment Share on other sites More sharing options...
37lover Posted March 11, 2020 Share Posted March 11, 2020 Raf96,If I understand your wiring arrangement correctly you are simply adding droppers spaced around your layout to a bus circuit. So if can you not disconnect the feed from say your first Brimal board to the second and .... ah just realised you say you were part way through wiring the first board! In which case either take up Rog's suggestion or use another temporary replacement choc block for your first connection board and see if that works [rather than mess up the Brimal board]. You've only(!) got 18 terminals x 2 on the board so if you are half way through that's only 9 x 2 droppers to undo & refix! Link to comment Share on other sites More sharing options...
96RAF Posted March 11, 2020 Author Share Posted March 11, 2020 Each terminal on the board is double wired and they were a pest to get into the terminal holes, so a plan is hatched to prove the board is at fault by using an unpopulated board direct without any droppers at all, just the buzzer. If it yelps then I can see if the resistor will cut or if it is surface mounted then all bets are off for using the buzzer. I will use a Select 1-amp psu and see if it browns out from a short as I attach each dropper. Link to comment Share on other sites More sharing options...
96RAF Posted March 13, 2020 Author Share Posted March 13, 2020 I desoldered one end of the in line resistor on a spare board and checked with the buzzer - all quiet untill I invoked a short. As I am wiring between 150 and 180 dropper pairs to a total of five of these boards the buzzer has gone back in the drawer, in favour of the Select 1-amp psu method. This picked up a dodgy buffer stop led by showing a short (EO - emergency off) and it reacts immediately to the coin test, so I am happy it will pick up a crossed dropper. I just have to wire in a switch to isolate the controller during soldering operations, even though my iron has a dead tip - some cheapie irons can have a potential on the tip high enough to kill most electronics. Decided to have a break from soldering this weekend and finish off the lift out section instead, which will now be a slide in section with the plug in choc block connectors at the back so they connect as you push the section firmly into place. A pair of locking bars will secure the section against movement. I’ll put some pictures up of the new design as I go along. Link to comment Share on other sites More sharing options...
96RAF Posted March 14, 2020 Author Share Posted March 14, 2020 Slide in section connectors mounted on the back stop blocks seem to work OK, so I will plod on with the infrastructure for the two bridges across the slider section. slider open/media/tinymce_upload/ead34a47cb2155c8bb3c2cc0445f1bd1.JPG slider closed/media/tinymce_upload/20a7370585fd55bb93453d8d42ba44a9.JPG The connector on this side feeds the main bus to the bridge track bus and back to the left hand isolated section. Same idea on the other side to feed that isolated section from the bridge tracks. This means that when the bridge section is removed there is an isolated section either side of the gap. When the bridges are replaced track power is restored to the isolated sections. Lock bolts will secure the sliding section in place to ensure all bridged tracks line up OK. The slide action mates the connectors every time with little effort and means the bridge tracks will match up without any chance of damage as could have hsppened with a lift-out section./media/tinymce_upload/3ccecde815c7a6d9d4d21bc10d257e94.jpg Having listened to peer advice I have decided to ditch the RH points pair (16A&B in the trackplan above) and replace it with a relocated LH pair (linking the run through red and blue tracks between points 6 and 7 pairs) to allow stock leaving the sidings to get from the blue line onto the red line without reversing. Link to comment Share on other sites More sharing options...
96RAF Posted March 31, 2020 Author Share Posted March 31, 2020 As a break from soldering droppers (about half way there now) I built a Metcalfe Coal Drop kit and had to bash it a bit to get it to fit into the incline. It is designed to have the track built up a ramp after the kit is placed, not the other way round, but I think it looks OK, better still when there is some scenery to blend it into later. The topside terminal boards for the track bus are working out well, and they are reasonably tidy. I shall hide them under some infrastructure later. /media/tinymce_upload/591e69eeef06a3c9da38839fcd41dc9f.JPG I also had the hoover out, tidied the place up a bit and scattered a few previously built kits about for effect. Several bits of cardboard have been pinned in place to see what the viaducts, etc might look like. /media/tinymce_upload/80514b0795d0e0844ccf9a48a5819b05.JPG Then I ran a Class 47 round. Only one derail and that is coming off the top of the hill on the RH side below, just where the signal lamp gantry is. but only when selected straight, OK when the loco crosses loops. A bit of investigation to do there. Extra pins per WTDs standard fix probably needed.The slide out section safety cutout for the track power works as advertised. /media/tinymce_upload/1309482e1fb318bf064d837d67bd762a.JPG Link to comment Share on other sites More sharing options...
Howbi Posted April 2, 2020 Share Posted April 2, 2020 Hi Rob, came across this etailer of components... https://www.rkeducation.co.uk/ ........may have some kit useful for your new layout..........HB Link to comment Share on other sites More sharing options...
96RAF Posted April 2, 2020 Author Share Posted April 2, 2020 Hi Rob, came across this etailer of components... https://www.rkeducation.co.uk/ ........may have some kit useful for your new layout..........HB Some usefull stuff there Howard. Link to comment Share on other sites More sharing options...
96RAF Posted April 16, 2020 Author Share Posted April 16, 2020 A bit of Metcalfe kit building - single road engine shed.May need to find a better home for it. /media/tinymce_upload/09aca20f9e61eb20f9b13a8ca2c59cc8.JPG Link to comment Share on other sites More sharing options...
96RAF Posted May 7, 2020 Author Share Posted May 7, 2020 The next task is to improve my manual points switching panel. /media/tinymce_upload/cc95fd5ab23c15ca0bee116b3adc5bc5.jpg It needs new labels on the topside and on the other side the old Cat-5 wiring which was just about adequate for a short run to the point motors requires replacement with some beefier wires. A fiddly job with not much room for error, but hopefully only needs doing once. /media/tinymce_upload/605ae481cb785a8245704b1707d42fe6.jpg Link to comment Share on other sites More sharing options...
96RAF Posted May 8, 2020 Author Share Posted May 8, 2020 That’s more like it..... I‘m happy that will do the job./media/tinymce_upload/b15f89388fffa3d197d350f7a403f08e.jpg I only had two wire colours so I had to resort to traditional ringing out point to point to ensure one end matched the other.When you spot the apparent repeated error I will explain why it isn’t wrong. Link to comment Share on other sites More sharing options...
Howbi Posted May 8, 2020 Share Posted May 8, 2020 There's a brown & blue out of sync at the end of each block.........HB Link to comment Share on other sites More sharing options...
96RAF Posted May 8, 2020 Author Share Posted May 8, 2020 There's a brown & blue out of sync at the end of each block.........HBCorrect Howard - when I originally set up the 2-pole 6-way rotary switches for some reason one pair of ways (1, 7, & 13) is out of synch so although I soldered to the tags per the switch configuration document this pair on each switch rings out wrong, so I swapped the wires over at the choc block end rather than desolder/resolder at the switches. It was the same on the old wiring according to my archive wiring diagram, which I referred to after the event as usual. No problem as long as it is documented for future reference. Link to comment Share on other sites More sharing options...
96RAF Posted June 9, 2020 Author Share Posted June 9, 2020 A bit more progress.This is the slide out twin bridge section with a bit of scenery added. It was a bit of a bodge getting the Metcalfe kit parts to fit the span available, so some architectural features are structurally misplaced, but I do not care - it will not fall down. Viewed from the back side showing the push in connectors that enable/disable power to the bridges and the isolated safety sections either side of the gap./media/tinymce_upload/dc7d10031933a956d0a3176d81305897.jpg This is it viewed from the outside of the layout. I need to fit a couple of catches to hold the slide in place although the connectors grip well enough./media/tinymce_upload/3df78eb8cb603fb01ba8e860b19afdb9.jpg Lots more little details to touch up like raw edges of card, rail bed to do, jetty walls and fittings, etc but they will get done when I have filled the river up with ‘water‘. I am hoping the grey river bed will shine through as a reasonable base water colour when the waves are added. Link to comment Share on other sites More sharing options...
Derek 19B Posted June 10, 2020 Share Posted June 10, 2020 Looking good, like the double river crossing.Derek Link to comment Share on other sites More sharing options...
96RAF Posted December 30, 2020 Author Share Posted December 30, 2020 Nothing much to report for ages as wiring is not exactly an interesting page filler. I have been doing a bit of scenic work adjacent to the bridge section though and will take some pictures later. Main activity behind the scenes has been trying to get the points to work reliably when commanded from RM, so I can use RM as intended to run the layout. At present they are all surface mounted solenoids of both Hornby standard and small types depending upon how much trackside space I have to plant them. They are currently rigged to operate only from R8247 DCC accessory decoders for now, until I have worked out the best method of using the relay modules I bought for manual control in parallel. Unfortunately solenoid success without a CDU in circuit has been at best about 60-70%. The R8247s just do have enough grunt operating from DCC voltage. The paired solenoids are resisting working together and some of the solo ones are refusing to work at all in one or both directions. Just a case of methodically wringing out the wiring again, but I am rapidly losing faith in solenoids so I decided to have a look at motor driven points instead. I am however reluctant to pay the going rate for the likes of Cobalt IP motors nor do I want to have to faff about mounting them under the layout, although I have plenty of headroom for them. Fitting them to the elevated sections may have been a challenge though . . . With that in mind I bought five of these tiny motor - gearbox units to play with. They are 12v DC with a 50:1 ratio gearbox giving an output shaft RPM of 400. The motor is 16mm long x 10mm wide, the gearbox 9mm long and the output shaft 55mm long but it can obviously be trimmed to length. Operating current is quoted in the spec as 170mA, but no indication in the spec of stall current so they could be marginal for direct operation by a DCC accessory decoder./media/tinymce_upload/0be06ae5eff6ffa37c6fd6cece376f82.png As proof of concept I built this test mule, which comprises a guide rail that locates the motor, a wooden driver ‘nut’, a pair of limit switch microswitches and a linkage twixt the motor drive unit and the point tie-bar made from a standard point motor extension bar. I used a small bell-crank robbed from a duff Hornby surface mount solenoid motor which gives approximately 2:1 mechanical advantage. A sprung centre-off reversing switch is provided to inch the motor thus allowing fine adjustment of the limit switches. Diodes provide a back-out current path from the limit switch stop position at each end of travel. In the final application the motor will auto cut out at end of travel and a simple ON-ON switch or DCC >> or << direction command will be all that is necessary. /media/tinymce_upload/ffd403e23373e26a1a639590935f43c6.JPG Below (just about) shows the swinging link between the bell-crank and the nut runner to allow for the arc of travel of the bell-crank. A new design will deploy a sliding link or a fixed link with a slot to sort this out. Working at this size is a tad fiddly for my old eyes and stiff fingers, but we are getting there./media/tinymce_upload/564f4ac3716b550370a5d2a1a0f66a06.JPG There obviously needs to be some material and geometry redesign of the nut runner and operating linkage but the basics are there. The ultimate will be 3-D printed parts that the motor can be assembled into and the whole unit screwed down to an adjacent point and connected to a controlling power source. This source will be DC or DCC as required with thanks to Ed Cairns in Canada who is working on an associated electronics module that will work from either power source and will sense motor current as it loads up at end of travel, which if proven reliable will replace the interim mechanical limit switches. More info as I make it happen. Link to comment Share on other sites More sharing options...
96RAF Posted January 2, 2021 Author Share Posted January 2, 2021 I have had a light bulb moment in the design for this motor driven point actuator, based on this simple cable conduit./media/tinymce_upload/eb1a24c886ab4671c14df4be0afa47f6.JPG The conduit cover when lubricated with furniture polish is a secure but easy sliding fit on the main housing and as you can see the motor-gearbox unit sits nicely inside the conduit housing. The motor output shaft nut runner will attach to the back of the slider and a shaft support bearing will plug the left hand end of the housing. The new design will still use limit switches to control the motor finite travel but this is not now critical. The point tie-bar actuation will be by way of a 3.5mm thick ramp glued to the slider. This means the required tie-bar travel can be spot on. The housing will be mounted on its side with the slider facing the point and a spring link will connect to the tie-bar and ensure the point travel follows in reverse when the ramp is down. The transverse push-pull will get rid of the need for that pesky bell-crank and critical set-up. Slotted lugs will be fashioned in the housing to accurately mount the device to the board. I will post photos when the new mock up has been assembled. Link to comment Share on other sites More sharing options...
96RAF Posted January 4, 2021 Author Share Posted January 4, 2021 Been doing a bit of scenic work ... ... a long way to go but getting there whilst the mojo is running. Bridge to tunnel on two levels.../media/tinymce_upload/395b04dc9e79b46f97013469a45ab858.JPGGoods Depot snd Hi-Level station.../media/tinymce_upload/e6653f786e482165c188ad4e968ef663.JPGSidings and escape road from Coal Drop.../media/tinymce_upload/bab78341d2c8e6912a3aa39602732708.jpg Link to comment Share on other sites More sharing options...
Bulleidboy Posted January 4, 2021 Share Posted January 4, 2021 It's looking very good Rob. Given the room I think I'd go for a "looped eight". BB Link to comment Share on other sites More sharing options...
96RAF Posted January 16, 2021 Author Share Posted January 16, 2021 @barry - I do like a folded 8, bags of running line for the same footprint - but you need a crossover.New Point Motor - Second prototype . . .Still needs a bit of refining of the ramp length but the basic principle of exact 3.5 mm lateral displacement of the tie-bar is solid. /media/tinymce_upload/2328a83507008d522dc731c035f2e0a5.jpgThe small grey rectangle is a chunky block to interface the tie-bar such that the ramp can move it without bending the tie-bar. It also spaces the motor unit away from the track to provide clearance for stock coming off the bend. The ramp is too long as built (25 mm) as it takes to many seconds to move the treaded output rod runner fully from one point direction to the other. The travel limit microswitches will be actuated by the bit sticking out at the top, which is also threaded to act as the output shaft nut runner. Not shown is the return direction spring mechanism which will bias the tie-bar towards the point motor. It may be as simple as using one of the travel limit microswitches. To make the motor a snug fit in the conduit housing I used three layers of shrink wrap sleeving on the motor casing. A dab of hot glue will fully secure it later. Prototype 3 will incorporate hold down lugs and a bracket for the microswitches. Going well so far. Link to comment Share on other sites More sharing options...
96RAF Posted January 16, 2021 Author Share Posted January 16, 2021 This is the schematic for it.../media/tinymce_upload/3ffae4ceb5834558630fb0884a294702.png Link to comment Share on other sites More sharing options...
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