Adam Posted September 4, 2017 Share Posted September 4, 2017 A question for EM modellers. How much clearance do you need between the inner face of the slide bars and the outer face of the mainframe? I am building the test chassis to P4 standards, however I am aware that EM modellers tend to use wider wheels. Gordon A Gordon, I'm not sure that this is the critical dimension since depending on the width over the outside of the frames (and the prototype) it will vary. EM back to back is 16.5, so absolute maximum width over frames would be a smidge over 15mm. Surely the width over wheel faces is the thing that is likely to be a limiting factor? Practically, that will be the width over wheel boss plus the depth of rod/fixing and this will depend on the wheels being used. The choice would seem to be the Hornby wheels recycled/bushed/longer axles, whatever), Gibson wheels (which do you have in mind?) or Markits. I have no idea about the former or latter, but could work out the Gibson option assuming you're thinking of 4839G (intended for the industrial Garratt) since I have a set of this in stock, somewhere. From that I should be able to fathom out what workable piston rod centres would be if you can tell me how wide the slidebars/crossheads are. So, 1. what's the width over frames of this 'P4' version? 2. with that, what are the piston centres? And, finally, 3. How wide are the crossheads? Adam Link to post Share on other sites More sharing options...
davknigh Posted September 4, 2017 Share Posted September 4, 2017 Gordon, FWIW the slide bars on both .Chris Gibbon's RSH and Neilson tank are set for about 26mm inside measurement and any allowances for narrower gauges come from the frame spacing. That said, compromises have to be made with the front coupling rod bearing to suit P4 and clearances are quite tight. HTH David 1 Link to post Share on other sites More sharing options...
RichardMarshall Posted September 8, 2017 Share Posted September 8, 2017 Gordon David recommended I have look at this thread and it certainly looks extremely interesting. You can certainly put me down for one of the P4 kits. The 'up the skirt' photos are very good with plenty of detail. You are to be commended for your effort. Richard Link to post Share on other sites More sharing options...
Gordon A Posted September 13, 2017 Author Share Posted September 13, 2017 (edited) Right back on the Peckett chassis having spent nearly a week on my old Land Rover. Firstly the slide bars. This shows the slide bars, firstly soldered together, secondly as removed from the etch. Inbetween the slide bars is a half etched overlay. The slide bars are made up of two layers, one folded on top of the other. I have soldered a couple of scrap pieces of etch across the pair of slide bars to ensure that they remain parallel. I sat the cut out pair on top of the etch for the other side before soldering the scrap pieces in place to ensure they are set at the correct distance apart. Next cylinder and slide bar bracket. I have fitted Gibson 13mm Industrial Beyer Garratt wheels on the front axle, representing the 3ft 2.5" wheels that were fitted at some rime. The cylinder ends fold up, with a fold out tab that locates the cylinder in place on the main frame at the correct angle. The cylinder is held in place by a 12BA screw and nut. I have then added the slide bar bracket. This consists of two layers of etch. As you can see the clearance between the bracket and the wheel is paper thin. The other option is to fit Gibson Black Hawthorn wheels that are 10 spoke, 3ft 0.5", 12mm diameter. This will increase the clearance between the front wheels and the slide bar brackets by 0.5mm. Gordon A Edited September 13, 2017 by Gordon A 1 Link to post Share on other sites More sharing options...
davknigh Posted September 13, 2017 Share Posted September 13, 2017 Thanks for all this Gordon, it will all be very useful when the rest of us come to build our version. On the matter of wheels, true there is clearance to be gained by using the Black Hawthorn wheels but the cosmetic advantage is on the side of the Garratts which will look closer to the Pecketts from "normal viewing distances". I'm hoping a few careful strokes of a file will make the difference plus some VERY careful mounting of the wheels on the axle. Just out of curiosity, what wheels were recommended for the original kit? Cheers, David Link to post Share on other sites More sharing options...
Gordon A Posted September 13, 2017 Author Share Posted September 13, 2017 Thanks for all this Gordon, it will all be very useful when the rest of us come to build our version. On the matter of wheels, true there is clearance to be gained by using the Black Hawthorn wheels but the cosmetic advantage is on the side of the Garratts which will look closer to the Pecketts from "normal viewing distances". I'm hoping a few careful strokes of a file will make the difference plus some VERY careful mounting of the wheels on the axle. Just out of curiosity, what wheels were recommended for the original kit? Cheers, David David, I don't know as all I have is an exploded diagram for the chassis. Gordon A Link to post Share on other sites More sharing options...
Gordon A Posted September 18, 2017 Author Share Posted September 18, 2017 (edited) Here is a side on shot of the Hornby Peckett sat on the CSP etched frames. A view of the chassis looking at the top You can see that the body mounting holes have to be filed out to a 2mm wide slot to use the body's securing holes. As previously stated the wheels are 13mm diameter for the industrial Beyer Garratt. A view of the chassis looking at the underside The slide bars need tweaking to set them parallel to the main frame. The slide bars are etched over length which is a good thing IMHO. They should end at the slide bar bracket and not protrude past it. I have 5.3mm clearance between the slide bars and the main frame. The distance between the outside faces of the main frames is 15.75mm, plus 2 x 5.3mm should give an overall distance between the inside faces of the left and right side slide bars as 26.15mm. If you need a greater clearance two packing squares, each 15 thou thick, have been included for each cylinder. The three sets of slide bar brackets, each two layers, appear to be set for the same clearance. So for a greater clearance you will have to do a bit of cut and shut. As my local model shop is open tomorrow I will try and buy some micro bore tube and rod for the brake gear. At some stage at Scaleforum I will try and have a talk with Chris Gibbons re a suitable gear box. Gordon A Edited September 18, 2017 by Gordon A Link to post Share on other sites More sharing options...
davknigh Posted September 18, 2017 Share Posted September 18, 2017 Wonderful! Thank you very much Gordon, oh, and enjoy Scaleforum!! Cheers, David Link to post Share on other sites More sharing options...
Norton961 Posted September 19, 2017 Share Posted September 19, 2017 Excellent work Gordon, your efforts are appreciated. David Link to post Share on other sites More sharing options...
Gordon A Posted September 21, 2017 Author Share Posted September 21, 2017 If any one is interested I will try to remember to bring the chassis with me this weekend. Gordon A Link to post Share on other sites More sharing options...
Mad McCann Posted September 21, 2017 Share Posted September 21, 2017 You do realise of course that we've lined you up for a Barclay next... ;-) D. Link to post Share on other sites More sharing options...
PenrithBeacon Posted September 21, 2017 Share Posted September 21, 2017 If any one is interested I will try to remember to bring the chassis with me this weekend. Gordon A Which stand will it be on ? Regards Link to post Share on other sites More sharing options...
PenrithBeacon Posted September 21, 2017 Share Posted September 21, 2017 I received two sample CSP chassis etches from Ian Young, one is Hercules and the other Henry Cort. Lost wax cast crossheads and piston rods were included with the samples. 00, EM and P4 spacers are already included. ... I will check the two sets of frames to see which best matches the Hornby Peckett. I understand that may be Hercules. ... Gordon A Following in from this, would it be fair to say that you are adapting the CSP design? Regards Link to post Share on other sites More sharing options...
Gordon A Posted September 21, 2017 Author Share Posted September 21, 2017 Yes PP the kit is well designed, goes together well and fits with a few strokes of a file. There are a few missing components which I assume are elsewhere on the kit etch. There will be some additional parts drawn up on a extra etch such as the lower boiler barrel and a set of spoke overlays. I will list the bits on the additional etch in due course. Gordon A Link to post Share on other sites More sharing options...
Gordon A Posted September 21, 2017 Author Share Posted September 21, 2017 In my last update I forgot to mention that I used a spare spacer soldered on top of the back spacer to provide a rear chassis securing point to the body. Yesterday and today I concentrated on the brake gear. My first surprise was that in the etch there was no provision for the front brake hangars either parts or holes in the frames. The second was that the brake hangars appeared to be 2mm too short. If you look closely at the brake hangars you will see the original top hole lower down. I lengthened the hangars 2mm with some scrap etch but did not take the time to file to shape so the addition looks a bit crude. New ones will be on the additional etch. Looking at the pictures I am not sure that 2mm might not be a shade too much. There was also no pull bars provided in the etch linking the front to the rear brake hangars. The next job was to add the rear brake cross shaft using 1mm tube. On Henry Cort the brake shaft does not pass through the mainframes but is mounted in some blind bearings bolted inside the shaft. In future I think I will drill out the middle bolt hole in the frames and use 0.5mm wire to locate the cross shaft. The current kit does not include a lever for the steam brake cylinder, just a lever for the hand brake. The steam brake lever will be included on the additional etch. I will also try to provide an anchor point for the vertical pull rod from the steam brake cylinder. Time for tea and to start packing for Scaleforum. Gordon A 2 Link to post Share on other sites More sharing options...
davknigh Posted September 21, 2017 Share Posted September 21, 2017 Gordon, Are you thinking of making the brake gear removable in the same way as Chris does? It looks like you have gone down that path which is a Good Thing IMHO. You seem to have the clearance between the front driver and the motion bracket sorted. Thanks again for your efforts. Cheers, David Link to post Share on other sites More sharing options...
Gordon A Posted September 21, 2017 Author Share Posted September 21, 2017 Gordon, Are you thinking of making the brake gear removable in the same way as Chris does? It looks like you have gone down that path which is a Good Thing IMHO. You seem to have the clearance between the front driver and the motion bracket sorted. Thanks again for your efforts. Cheers, David Hello David, I have used Chris's method of mounting the brake hangars, but have soldered the pull rods. I think when the new etched components are made it will be possible to use Chris's system of mounting the brake gear. Gordon A Link to post Share on other sites More sharing options...
davknigh Posted September 21, 2017 Share Posted September 21, 2017 Hello David, I have used Chris's method of mounting the brake hangars, but have soldered the pull rods. I think when the new etched components are made it will be possible to use Chris's system of mounting the brake gear. Gordon A Excellent! I see by the pics you have discovered, as have I, that the Salters are not fastened at the top end :-(. Cheers, David Link to post Share on other sites More sharing options...
High Level Kits Posted September 22, 2017 Share Posted September 22, 2017 To achieve the correct buffer height, you may need to trim a bit off the frames Gordon, as the Hornby footplate will be thicker than the etched one for which the chassis was intended. Link to post Share on other sites More sharing options...
PenrithBeacon Posted October 14, 2017 Share Posted October 14, 2017 Any news? Regards Link to post Share on other sites More sharing options...
Gordon A Posted October 14, 2017 Author Share Posted October 14, 2017 The additional components are currently being drawn on Monday evenings, so is taking a bit longer. Gordon A Link to post Share on other sites More sharing options...
davknigh Posted October 15, 2017 Share Posted October 15, 2017 Thanks Gordon, your efforts are greatly appreciated :good: Cheers, David Link to post Share on other sites More sharing options...
PenrithBeacon Posted October 15, 2017 Share Posted October 15, 2017 The additional components are currently being drawn on Monday evenings, so is taking a bit longer. Gordon A Link to post Share on other sites More sharing options...
Gordon A Posted December 3, 2017 Author Share Posted December 3, 2017 Another step down the road. Finally the additional Peckett parts test etch. Sorry for the poor picture. Included in the etch are: Additional new parts: A - Lower boiler barrel. B - Smoke box back C - Firebox front D - Levers for steam brake cylinder E - An overlay to the back from spacer which a rear screw hole for the body and holes for the hand brake and steam brake rods. F - Wheel spoke overlays. G - Cylinder wrappers. Replacement of existing parts: 23 - Firebox and ash pan bottom. EM and P4 24 - Crank pin square brass bearing overlays. 71 - Middle frame spacer EM 74 - Leading coupling rod crank pin brass overlay 87 - Brake hangars front and back 88 - Brake shoe detail overlay. 91A - Front sections of the brake pull rods linking the leading and driven axle brakes. My next job is to fit these additions to my current chassis. Gordon A 4 Link to post Share on other sites More sharing options...
davknigh Posted December 3, 2017 Share Posted December 3, 2017 Excellent!! Looking forward to seeing the next stage, as time and season permit, of course. Cheers, David Link to post Share on other sites More sharing options...
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