chris_w Posted December 9, 2014 Share Posted December 9, 2014 Probably a silly question now.... I've got the same rivet press (metaphors) and all I manage to do is punch holes with is. I tried setting the depth shallower but it didn't seem to make much difference. What am I doing wrong? Chris Link to post Share on other sites More sharing options...
Sandy Harper Posted December 10, 2014 Author Share Posted December 10, 2014 Probably a silly question now.... I've got the same rivet press (metaphors) and all I manage to do is punch holes with is. I tried setting the depth shallower but it didn't seem to make much difference. What am I doing wrong? Chris Hi Chris I seem to recall when I got mine, several moons ago, I found the same problem especially in half etched material. What I did was to take of the sharp point on the punch with some wet and dry or a sharpening stone to give a more rounded point rather than a pin sharp one. Its trial and error to get it right but it should work ok. Sandy 2 Link to post Share on other sites More sharing options...
Sandy Harper Posted December 20, 2014 Author Share Posted December 20, 2014 The following set of photographs show the first stages involved in 'splitting ' the chassis for the tender pickup. The 5mm thick Perspex I get already cut to 24mm wide from my local sign maker. He usually has plenty of off-cuts and he uses a band saw. All I need to do is dress the edges with a fine file or some glass paper and cut to the length I need. The hole in the middle is to pass connection wires through. I this instance I needed to adjust the fitting of the brass spacers so that the top of the spacer would be flush with the to edge of the chassis frames. This was so that the Perspex spacer did not obstruct the bearing holes or the brake cross hanger beams. The next job is to glue and fit fixing bolts. If anything is not clear please ask. Regards Sandy 7 Link to post Share on other sites More sharing options...
John K Posted December 22, 2014 Share Posted December 22, 2014 Hi Sandy, This would look great in the pages of the Gazette as a series of photos with extended captions. Merry Christmas and a Happy New Year. John Link to post Share on other sites More sharing options...
Sandy Harper Posted December 22, 2014 Author Share Posted December 22, 2014 Hi Sandy, This would look great in the pages of the Gazette as a series of photos with extended captions. Merry Christmas and a Happy New Year. John Thanks John, I'll keep taking photos!! Seasons greetings to you and Jackie Sandy Link to post Share on other sites More sharing options...
Sandy Harper Posted December 23, 2014 Author Share Posted December 23, 2014 I have glued the Perspex spacer to the underneath of the two outer brass spacers and drilled through the side frames into the Perspex, tapped, and screwed in 8BA counter sunk screws. Belt and braces. 8BA cheese head screws through the end spacers. Two are needed, as the brass spacer will be split down the centre to isolate the two frames. Next job is to provide some springing and movement to the centre axle bearings. First I rubbed on some black permanent marker so that the markings I will make will show up easily. Using an engineers square I drew vertical lines either side of the axle bearing hole, and one along the bottom, joining the two vertical lines and about 1mm below the bottom of the axle bearing hole. I used a spare bearing with a smaller radius top hat to draw where I wanted to extend the bearing hole to and act as a guide for filing with a round Swiss file. The amount of brass you need to remove is very small so take it slow and check with the bearing on a regular basis. 3 Link to post Share on other sites More sharing options...
Sandy Harper Posted December 25, 2014 Author Share Posted December 25, 2014 Once the bearings are moving nicely in their slots, I drilled a 1mm hole through the bearing about 1.5mm from the tophat part of the bearing so that it is clear of the chassis side when the bearing is fitted. I then cut two lengths of piano wire about 3cm long... ...grind down the ends of the cut wire using a disc in the minidrill (use safety glasses!!)..... ....then bent the end 2mm to 90 degrees ....solder the other end to the chassis frame so that the wire is horizontal with the centre of the hole and the bend central the other way...... Replace the bearing in the chassis and spring the wire into the hole. This method not only holds the spring in location but also prevents the bearing from turning with the chassis, which would lead to excessive wear in the bearing slot. The end of the piano wire will not significantly effect the rotation of the axle within the bearing. One of the easiest ways of springing I know of and I'm sure, used by many on here. Thanks Jazz! Sandy 4 Link to post Share on other sites More sharing options...
Barnaby Posted December 25, 2014 Share Posted December 25, 2014 Great and intriguing work Sandy, a very useful explanation & reference source. Merry Christmas and a Happy new year to you and yours. Regards Link to post Share on other sites More sharing options...
Guest Isambarduk Posted December 25, 2014 Share Posted December 25, 2014 I have used a similar arrangement, Sandy, but I would shorten the short leg of the L-shaped piano wire so that it does not press on the axle but rather it presses on the bearing; after all, that's what the bearing is for - to take the load. David Link to post Share on other sites More sharing options...
Sandy Harper Posted December 25, 2014 Author Share Posted December 25, 2014 I have used a similar arrangement, Sandy, but I would shorten the short leg of the L-shaped piano wire so that it does not press on the axle but rather it presses on the bearing; after all, that's what the bearing is for - to take the load. David Merry Christmas David Many thanks for your comment. The amount of 'spring force' is in fact very soft and I doubt it has any effect on the axle, the wire takes no appreciable load and in effect is only displaced slightly by the axle. I have used shorter 'L's in the past but found that if you get it too short it can pop out of the bearing with the rotational forces under certain conditions. So I tend to leave it long to prevent this. Kind regards Sandy Link to post Share on other sites More sharing options...
Guest Isambarduk Posted December 26, 2014 Share Posted December 26, 2014 "The amount of 'spring force' is in fact very soft and I doubt it has any effect on the axle, the wire takes no appreciable load and in effect is only displaced slightly by the axle." Sandy, do the hornblocks normally ride at the top of their slots/hornguides, in which case I follow what you are saying? Otherwise it seems to me that the springs are transferring all the load (ie weight of the loco) directly to the axles and the bearings practically non at all. After all, only the springs are pressing down on the axles, the hornblocks (bearings) are only holding the axles in their correct horizontal alignment. Link to post Share on other sites More sharing options...
Sandy Harper Posted December 27, 2014 Author Share Posted December 27, 2014 "The amount of 'spring force' is in fact very soft and I doubt it has any effect on the axle, the wire takes no appreciable load and in effect is only displaced slightly by the axle." Sandy, do the hornblocks normally ride at the top of their slots/hornguides, in which case I follow what you are saying? Otherwise it seems to me that the springs are transferring all the load (ie weight of the loco) directly to the axles and the bearings practically non at all. After all, only the springs are pressing down on the axles, the hornblocks (bearings) are only holding the axles in their correct horizontal alignment. Hi David, Yes, the bearings sit at the top of the chassis slot taking the weight of the tender. The spring only exerts a downward pressure when the track drops away from below the wheel, maintaining electrical contact. Sandy Link to post Share on other sites More sharing options...
ozzyo Posted December 27, 2014 Share Posted December 27, 2014 Hello Sandy, as this set of frames is for a six wheeled tender I would also allow a small amount of upwards travel, unless you are going to spring one of the other axles. If you don't have the upwards movement you could end up with the tender see sawing when it gets to a bump in the track. I'm also in agreement with David about the length of the short leg I'd try and keep it inside of the bearing so that it's not touching the axle (steel on steel is not that good in a friction bearing, small as the surface is). If you think about it if the spring has a force of 25grms. at the wheel rim all of that force is going through a surface of 0.62mm sqr. (if I've got my maths right), that is going to be a lot of pressure on a small surface. In your last post above you said " the spring only exerts a downward pressure when the track drops away ETC." This is not true the way you have the spring set up it is always exerting pressure on the wheel as you have the spring on the axle C/L then you have the length of the tail 2mm all increasing the pressure, so this axle is "well" preloaded. As a test fit all the wheels or dummy axles in all of the bearings and add small amounts of weight at the front and rear and see how much you have to add to get all six wheel on the track. ATB OzzyO. 1 Link to post Share on other sites More sharing options...
Sandy Harper Posted December 27, 2014 Author Share Posted December 27, 2014 Hello Sandy, as this set of frames is for a six wheeled tender I would also allow a small amount of upwards travel, unless you are going to spring one of the other axles. If you don't have the upwards movement you could end up with the tender see sawing when it gets to a bump in the track. I'm also in agreement with David about the length of the short leg I'd try and keep it inside of the bearing so that it's not touching the axle (steel on steel is not that good in a friction bearing, small as the surface is). If you think about it if the spring has a force of 25grms. at the wheel rim all of that force is going through a surface of 0.62mm sqr. (if I've got my maths right), that is going to be a lot of pressure on a small surface. In your last post above you said " the spring only exerts a downward pressure when the track drops away ETC." This is not true the way you have the spring set up it is always exerting pressure on the wheel as you have the spring on the axle C/L then you have the length of the tail 2mm all increasing the pressure, so this axle is "well" preloaded. As a test fit all the wheels or dummy axles in all of the bearings and add small amounts of weight at the front and rear and see how much you have to add to get all six wheel on the track. ATB OzzyO. Ok,ok, I bow to your superior mathematics. I will make the necessary changes next week. Meanwhile I am going to play with the portable layout tomorrow at the Llandrinio show. Kind regards Sandy Link to post Share on other sites More sharing options...
ozzyo Posted December 28, 2014 Share Posted December 28, 2014 Give over, to my superior maths! I can't spell that, that's mathematics+. Is that like sums at school? ATB OzzyO. Link to post Share on other sites More sharing options...
Sandy Harper Posted December 29, 2014 Author Share Posted December 29, 2014 Give over, to my superior maths! I can't spell that, that's mathematics+. Is that like sums at school? ATB OzzyO. Bloody 'ell, Can't even trust spell checker to get it right!! Of course it could be the Yorkshire spelling as they always manage to stick 'eee' in somewhere! Have a good Hogmanay!! Sandy Link to post Share on other sites More sharing options...
Sandy Harper Posted December 30, 2014 Author Share Posted December 30, 2014 The revisions, as per the learned suggestions posted on here, and via PM's, have now been incorporated into the tender chassis. The centre bearings now have an additional .5mm-ish upward movement and the front bearings have a .5mm-ish downward movement both assisted by .55mm sprung piano wire with the tails reduced in length. Now on with the tender tank. Happy New Year to all my readers. Sandy 3 Link to post Share on other sites More sharing options...
Sandy Harper Posted December 31, 2014 Author Share Posted December 31, 2014 I managed to get a little bit more done this morning plus a few photographs. The changes to the springing arrangement as described previously. From above.... .....from below. Sides and end of tender tank temporarily attached to the footplate to check for clearances and fit. Tank fully soldered up and the supports for the tank top attached. Rear corners filled and filed. The flare was done using a Metalsmith 'drilling table', with bending attachments, which I have described previously in my earlier posts. The tank top bent to shape and temporarily fitted. The front bulkhead from the front of the tender...... ....and from the rear. There are 3 separate bulkheads to choose from depending on the version of the tender you are building. This is the early front plate for the 3250 gal. version. Regards Sandy 6 Link to post Share on other sites More sharing options...
Sandy Harper Posted January 2, 2015 Author Share Posted January 2, 2015 The main tender is now soldered up including the outside frames, draw bar and rear buffing plate. I had a lucky break. I realised that I had forgotten to solder nuts on the top of the footplate to attach the chassis, so I soldered them on the underside instead. The lucky bit was that I had fitted the Perspex below the top of the frames so when I screwed it down it ended up .5mm below the footplate level giving me a convenient insulation gap. How good was that?? Sandy 10 Link to post Share on other sites More sharing options...
Sandy Harper Posted January 6, 2015 Author Share Posted January 6, 2015 I have added more detail to the tender but can't fit the brake gear yet until the wheels arrive (Yes, I know, forgot to order them, Again!) .....so back to the loco. Next up is the boiler/smoke box. The boiler/smoke box is a solid brass turning! and in this shot I am fitting the saddle to the smoke box, using a gas torch and 100 degree solder!! Ok, not really, the shot was set up after the brass had cooled down! But you get the idea. Sandy 8 Link to post Share on other sites More sharing options...
Sandy Harper Posted March 4, 2015 Author Share Posted March 4, 2015 Many years ago, too many to remember, I promised my self that I would only have one job on my workbench at any one time. I broke my rule!!! The consequence is that progress on all the projects slows down! However I am now seeing light at the end of the tunnel!! This was a job that I took on for a friend of mine. It is a preserved loco and has a rather strange lining layout. At least I have never seen it before. The front of the saddle tank was interesting!!! I could not get the smokebox to sit down correctly and I wasn't about to try and force it! The Skye Bogie is finally finished but I apologise for the rather poor photograph. I will take some better ones when I can get out doors!!! Regards Sandy 7 Link to post Share on other sites More sharing options...
ozzyo Posted March 4, 2015 Share Posted March 4, 2015 This was a job that I took on for a friend of mine. It is a preserved loco and has a rather strange lining layout. At least I have never seen it before. The front of the saddle tank was interesting!!! I could not get the smokebox to sit down correctly and I wasn't about to try and force it! P1080554.JPG Regards Sandy What has happened to the smokebox on the above loco Sandy? OzzyO. Link to post Share on other sites More sharing options...
Sandy Harper Posted March 4, 2015 Author Share Posted March 4, 2015 Hi Mate, If you look closely at the second photo you will see that the front splasher over laps the smokebox saddle by about 3mm. The smokebox is also designed to have the dart pass into the front of the boiler which is threaded and as you tighten the dart it holds the smokebox in place. I suspect that the reason I could non get it in place was the thickness of the paint undercoat and top coat that had reduced the gap between the splasher and the footplate. I wasn't going to force it!! When I delivered it, the Builder had it located without too much effort! Sandy Link to post Share on other sites More sharing options...
ozzyo Posted March 4, 2015 Share Posted March 4, 2015 Sometime these builder type people should do some of the painting as well. Click and the door closed on the cold night air. Link to post Share on other sites More sharing options...
M Wright Posted March 7, 2015 Share Posted March 7, 2015 The revisions, as per the learned suggestions posted on here, and via PM's, have now been incorporated into the tender chassis. The centre bearings now have an additional .5mm-ish upward movement and the front bearings have a .5mm-ish downward movement both assisted by .55mm sprung piano wire with the tails reduced in length. Now on with the tender tank. Happy New Year to all my readers. Sandy Link to post Share on other sites More sharing options...
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