Horsetan Posted November 19, 2014 Share Posted November 19, 2014 The SNGLPT site has a bit of information on the tenders as well: Click here, then on the sidebar click on "Chime", then "Archive", then click "A Tangle of Tenders". Link to post Share on other sites More sharing options...
david.hill64 Posted November 20, 2014 Author Share Posted November 20, 2014 David, There is an overhang: 2 1/4", see the attached detail from Doncaster drawing R-257 (the later batch of streamlined corridor tenders). The reason for showing this is that it shows both original and cut-back fairings. The actual front for a modified 1928 tender is also included. (And of course Sweedy is correct: the third tender is indeed one of the tenders shown in R-257. This research lark is harder than it seems.) Thanks Dave! Looks like I have even more work to do than I thought, but I had already mentally prepared for that. The etch was such a perfect fit from front to back! The photo is particularly interesting and also shows that the dragbeam is different, but I guess model curves are not to scale so there is little to do about that. The SNGLPT site has a bit of information on the tenders as well: Click here, then on the sidebar click on "Chime", then "Archive", then click "A Tangle of Tenders". Thanks Ivan! Yes in my googling I had come to that useful site, if only to prove that the tender is wrong for the chosen loco, but its identity still has time to change if required. I guess my weekend is sorted, though I had been hoping to start on the loco frames. Link to post Share on other sites More sharing options...
david.hill64 Posted November 23, 2014 Author Share Posted November 23, 2014 Well the butcher's apron has been donned, the gas axe lit and modifications made: The rear fairing had been soldered on by running a fillet along the edges. The application of a sharp scalpel allowed me to lift the fairing and then clean it and the surrounds. It has then been re-positioned as shown, fitted flush with the tender top. It looks about right. I had to put a small infill piece in place as the division top beading didn't come to the tender top. I have had difficulty finding suitable pictures. I guess it should be symmetrical with the RHS. I was similarly able to lift the front fairing on the LHS and part of the front plate. I then cut back the fairing so that it fitted against the top of the tender side. I then added a 1.5mm brass strip to the front to represent the overhang above the tender front plate. Finally I blended the RHS of the fairing to make the join to the tender top less conspicuous. I'll post photos when it is out of the paint shop. Link to post Share on other sites More sharing options...
david.hill64 Posted November 29, 2014 Author Share Posted November 29, 2014 It has been a very quiet week on the modelling front. Work has rather intruded on pleasure. I got the tender back in the paint shop, only to discover that I had run out of primer. I knew the can was nearly empty, but a quick flash over the rear fairing and that was it. I soldered two 6BA screws to some scrap brass strip. The screws are fitted into the chassis attachment points and allow the tender to sit clear of the floor for painting. I should have made on of the legs very long so it could be used to manouevre the tender when painting. I have a similar lash-up with washers and bent brass which will allow me to hang the tender upside down to do the lower surfaces. I will post a picture of that when fitted. So I have been out to the hardware store and replenished stocks and here is the tender on the painting table ready to be sprayed (other brands are also suitable). I do not recommend this activity when SWMBO is in residence. The lack of paint allowed me to start on the loco frames. I used a CD writer to mark up each axle bearing with the correct horn-blocks and am using the same pen to identify parts as they come off the fret. I had an attack of number blindness searching for part 70 - couldn't see it on the etch guide at all, but it was clearly marked. This will be fitted later. The frames have gone together well. I spent a long time wondering why they didn't appear to be square. I was using a long length of 3/16" tube through the rear bearings to check for squareness. One side was square and the other not. Only when I realised that the tube was bent did the reason become clear. I need to get some solid round bar I think - and make sire that it is straight! Next job is to fit the remaining hornblocks. The wonderful profile milled nickel silver coupling rods arrived this week, just in time for the setting up process. Now to keep my fingers crossed that the tender will look better. I must resist the temptation of having a peep until tomorrow. Link to post Share on other sites More sharing options...
N15class Posted November 29, 2014 Share Posted November 29, 2014 The tender looks much better now. Are the hornblocks independently sprung or is it compensated? Link to post Share on other sites More sharing options...
david.hill64 Posted November 29, 2014 Author Share Posted November 29, 2014 The tender looks much better now. Are the hornblocks independently sprung or is it compensated? Thanks! It will be a fully compensated chassis with the leading axle pivoting about a central point and each side of the rear two axles linked and pivoting about a mid-point tube. Link to post Share on other sites More sharing options...
david.hill64 Posted November 30, 2014 Author Share Posted November 30, 2014 So here is the tender about to get its lower surfaces painted. I set up the hornblocks using the Metalsmith setting rods and the coupling rods. And now I have come to a head scratching problem: how to fit the gearbox? You can see that the gearbox is a close fit between the axle bearings. I have also forgotten to cut the top out of the hornguides to allow the compensation beam to rest on top of the axle box, but that will be easily rectified with a slitting wheel. The problem is that the two halves of the axle are help together by a taper pin which can fit in one of two pre-drilled holes. One hole - with the pin in place in the picture above - is too close to the axle bearing and will force the wheel set to run to one side only if used. It is also located coincident with the gearbox bearing. The more central is located in line with the teeth on the final gearwheel. So what to do? At present I am thinking of removing the gearwheel grub screw, setting the gearbox central on the axle and marking the axle where the grub screw will touch. Then I am thinking of drilling into the axle and stub axle and using either a small screw in place if the gearwheel grub screw to hold everything together or possibly to use the taper pin instead of the grub screw. I suspect the former is a better option. I would really welcome any suggestions on the best way forward. Thanks, David Link to post Share on other sites More sharing options...
david.hill64 Posted November 30, 2014 Author Share Posted November 30, 2014 Forgot to add a shot with the wheels temporarily in place. Link to post Share on other sites More sharing options...
N15class Posted November 30, 2014 Share Posted November 30, 2014 I sometimes fit the bearings the wrong way around especially slaters ones that can have the extension reduced to give the wheels no side play. I like the cradle I will have to remember that one. Link to post Share on other sites More sharing options...
Rob Pulham Posted November 30, 2014 Share Posted November 30, 2014 I like the cradle I will have to remember that one. Me too, a neat idea - where would we be without scrap etch? Link to post Share on other sites More sharing options...
david.hill64 Posted December 2, 2014 Author Share Posted December 2, 2014 Last night was spent measuring up the wheels to see if my plan to use the gearbox grubscrew (or longer replacement) as a combined pin to hold the wheels together and key the gear wheel to the axle would work. Unfortunately the answer is no. The stub axle finishes coincident with where the grubscrew would be so it cannot be used to hold everything together. This is disappointing as I thought it would be an elegant solution. Whatever I do must allow the wheelset to be split while the axle is in the chassis as it will be impossible to drop out the motor/gearbox on the axle. It might be possible if the motor is split form the gearbox first but this isn't certain. Plan B is to remove most of the left hand gearbox bearing and significantly thin the the left hand axle bearing and hornblock so that the taper pin can continue to be used. I will also look at Peter's suggestion to invert the LH bearing rather than cut it. I am going to need spacing washers anyway so this may well be a good solution. I did try inverting both but ran out of clearance. My assertion that the cut outs to the hornguides to accept the compensation beam was fine in theory, but totally failed the practicability test as the diameter of the slitting wheel is too small. So the ob will take a bit longer than planned. Meanwhile the tender has gone back to the finishing shop to fill some small blemishes. So I will be rubbing down the filler and touching in. Then I will just have the gangway to complete. I was interested to see this loco for sale: it made me feel much better about getting the fairing wrong! http://www.ebay.co.uk/itm/O-GAUGE-KIT-BUILT-SILVER-FOX-LNER-BLUE-A4-LOCO-2512-/201027480931?pt=UK_Trains_Railway_Models&hash=item2ece2bed63 Link to post Share on other sites More sharing options...
hobbyhorse Posted December 2, 2014 Share Posted December 2, 2014 The position of the pin can be moved, as the photo shows. I've not had any problems with this method other than being careful when slotting the gear. I've also removed the side of the bearing which sounds drastic but still leaves a reasonable bearing surface, this was done on a clients model which runs on the large layout with no signs of problems from the reduced bearing. Simon Link to post Share on other sites More sharing options...
david.hill64 Posted December 2, 2014 Author Share Posted December 2, 2014 The position of the pin can be moved, as the photo shows. I've not had any problems with this method other than being careful when slotting the gear. I've also removed the side of the bearing which sounds drastic but still leaves a reasonable bearing surface, this was done on a clients model which runs on the large layout with no signs of problems from the reduced bearing. Simon Simon thanks for your input! I knew I had seen it done somewhere! This is exactly what I was thinking, but the boss on the gearwheel is right at the centre of the axle. I am not sure that I can get the taper pin through there and go into the meat of the stub axle. I am worried that it will be so close to the end that it will not secure the stub axle in place properly. I am also restricted to working with hand tools only, which limits options. So at present I am still working on the assumption that it will be Plan B as described. David Link to post Share on other sites More sharing options...
Horsetan Posted December 2, 2014 Share Posted December 2, 2014 Love those crossed helicals.... Link to post Share on other sites More sharing options...
JeffP Posted December 2, 2014 Share Posted December 2, 2014 I never thought I'd be glad for the simplicity of Slater's wheels....... Link to post Share on other sites More sharing options...
david.hill64 Posted December 3, 2014 Author Share Posted December 3, 2014 Plan B appears to have worked! Fitted the compensation beams: But had major surgery on the left hand central hornblock: It was a relied when it rolled freely in both directions, so I took saw to gearbox to thin down one bearing and now it fits! It has also run smoothly under its own power. Phew! Link to post Share on other sites More sharing options...
JeffP Posted December 3, 2014 Share Posted December 3, 2014 It was a relied when it rolled freely in both directions, so I took saw to gearbox to thin down one bearing and now it fits! relied? Link to post Share on other sites More sharing options...
Horsetan Posted December 3, 2014 Share Posted December 3, 2014 I think he meant "relief". Probably typing in a hurry. Don't let it worry you. Link to post Share on other sites More sharing options...
JeffP Posted December 3, 2014 Share Posted December 3, 2014 Tsk...should have seen that myself, "f" next to "d" on these daft keyboards. Quite why the new generation can't have alpha-numeric keyboards is beyond me. Link to post Share on other sites More sharing options...
david.hill64 Posted December 3, 2014 Author Share Posted December 3, 2014 Got it in one! I was in a hurry to get a celebratory drink! I think he meant "relief". Probably typing in a hurry. Don't let it worry you. Link to post Share on other sites More sharing options...
hobbyhorse Posted December 3, 2014 Share Posted December 3, 2014 Looking good. Simon Link to post Share on other sites More sharing options...
david.hill64 Posted December 6, 2014 Author Share Posted December 6, 2014 Free time in the last couple of days have been spent on the rear frames and front bogie. The magic words 'form and fit' appear in the instructions in respect of the rear frame extensions. It is fairly obvious where and how they fit, but a template would have been nice. It took me at least 30 minutes to get the first side as I wanted it, but having done that the other one was done in 30 seconds! At this point the instructions do not mention adding the rear springs and axleboxes but I decided that it was logical to do it. There was much more work involved in the rear section than I expected but it has turned out OK. The front bogie was relatively straightforward. The next job is to refit the driving wheels and assemble the cylinders. I will paint the frames before doing that. The tender is also ready to be sprayed again. I wasn't happy with the blending of the fairing so I have been busy with filler and grit paper. Link to post Share on other sites More sharing options...
david.hill64 Posted December 7, 2014 Author Share Posted December 7, 2014 Today's efforts have been directed at getting parts ready for the cylinders. The slide bars are formed from 6 nickel silver laminations soldered together and then cleaned up so that the crosshead is nice sliding fit without slop. I am not there yet but nearly so. The tender has come out of the paint shop and still needs more rubbing down before a final primer coat. Here is a sneak preview! Link to post Share on other sites More sharing options...
david.hill64 Posted December 10, 2014 Author Share Posted December 10, 2014 The crossheads and slide bars were fettled until a nice sliding fit was obtained and then I assembled the cylinders. All seemed to be going well: I completed the left side first. I don't know why but I always seem to do the left hand side before the right. I pushed the right hand slidebars into position, tack soldered, ensured the alignment was good and then firmly attached the slidebar using copious quantities of 188 degree solder. Then I looked at my handiwork and realised that I had soldered the bars upside down! Having done such a good job of securely fitting them to the cylinders I had to resort to a gas torch to get enough heat into the assembly to pull the bars out. That slightly affected the alignment of the laminated sections so I had to re-jig that. As Ozzyo so correctly observed: much better to check that all is well before soldering! Having done that and attached the valve rod guides etc I sat back for a rest and found a new picture of Merlin: only to discover that she had the GN pattern front guides, so I had to unsolder the LNER ones and fit the proper ones. I used a 1.4mm drill to align them. Once the various drop-offs had been corrected I was able to fit them temporarily to the chassis. The instructions suggest fitting the cylinder drains next, but I think they may get damaged so I will fit them later. Next job: valve gear! Link to post Share on other sites More sharing options...
scot6p Posted December 10, 2014 Share Posted December 10, 2014 Hi David, look at this web-site if you want to know how to do the valve gear http://www.7mmlocomotives.co.uk/gallery2/main.php?g2_itemId=6327 Len Link to post Share on other sites More sharing options...
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