dscott
Elder Statesman
Posts: 2,438
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Post by dscott on Dec 31, 2021 1:36:57 GMT
Superb again Roger. Another detail I missed added to the list of eventual bits to do. Yes the Hot Air Gun. Such a useful bit of kit we have 2 of them... They are also useful for speeding up a barbecue! Case hardened burgers and memories of the past.
David and Lily.
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Post by 92220 on Dec 31, 2021 8:55:53 GMT
Hi Roger.
One trick I learned for tinning large areas....spread the flux and then get a large blob of solder somewhere on the surface. While it is still fluid, wipe over the surface with a ball of paper towel, to spread the still liquid solder. I've used this method to tin quite large areas of steel plate. If the plate is completely covered with the solder, you can be sure that rust is not going to set in between the plates. Afterwards, when cold, I wash everything in cellulose thinners, to get all trace of flux off.
Bob.
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Post by Roger on Dec 31, 2021 9:26:33 GMT
Hi Roger. One trick I learned for tinning large areas....spread the flux and then get a large blob of solder somewhere on the surface. While it is still fluid, wipe over the surface with a ball of paper towel, to spread the still liquid solder. I've used this method to tin quite large areas of steel plate. If the plate is completely covered with the solder, you can be sure that rust is not going to set in between the plates. Afterwards, when cold, I wash everything in cellulose thinners, to get all trace of flux off. Bob. Hi Bob, That's the way I've been doing it, with flux on a small piece of cloth and also on a cotton bud. Steel isn't that keen on wetting, but at least once done it does stay wetted. I'll certainly use the tip of using thinners though to remove the flux. I've been using those little polishing wheels and the Dremel for cleaning up the finished part.
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Post by Roger on Jan 1, 2022 0:53:46 GMT
Happy New Year everyone! Last year, I added the fixing holes for the Chequer Plate to the Cylinder Cladding using this setup to hold it. All of the holes are referenced to the back of the cladding... 20211231_145851 by Timothy Froud, on Flickr ... and I added the rivet holes for the Lamp Irons at the same time. These are handed, even though the rest of the cladding isn't. 20211231_154728 by Timothy Froud, on Flickr The Cylinders need a small clearance for the heads of the M1 screws, so here I'm using the flat end of the morse taper socket to set the surface horizontal. 20211231_173741 by Timothy Froud, on Flickr They only need to be 0.6mm deep. 20211231_175049 by Timothy Froud, on Flickr I also chemically blacked the Chequer Plates, which took a couple of goes to get right. A few places didn't take the colour well, and one at the edge had got Solder on it which prevented it taking at all. I had to carefully scrape that back to the bare metal and try again. I decided to use the little abrasive wheels on the Dremel to remove most of it so I could get it all even again. In the end it came out fine. 20211231_223717 by Timothy Froud, on Flickr I just need to make the tapered spacer for the top sheet, and then I can get these finished. Actually, scratch that, I need to order more M1 hex bolts for the dummy ones on the covers before I can paint them. Still, the bulk of the Cylinder Cladding has now been done.
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Post by Roger on Jan 1, 2022 22:23:10 GMT
This tapered spacer sits on top of the Cylinder and supports the cladding. This is only necessary because I've modified the outline of the Cylinder profile from LBSC's design so that the top slopes less towards the frame. I could have made a small tapered spacer where the bolts go, but I thought it would be better to support the open edge of the wrapper. Tapered top spacer by Timothy Froud, on Flickr The chosen method of making these is frankly not that sensible, as is the design. However, it's an interesting problem to solve and I just fancied having a go at something a little different. I've got loads of 16mm Brass bar, so the fact that this is wasteful isn't of any consequence. Clearly this amount of overhang, 90mm, is going to create issues while machining near the end. It's also vital to set up the axis of rotation to be horizontal and parallel to the X-axis. 20220101_211009 by Timothy Froud, on Flickr Anyway, this is how it's being done, to the full finished size starting from the end so that the full section of the stock is available for support. 20220101_210951 by Timothy Froud, on Flickr I've hand written the code for this since I don't have Alibre CAM for this and I don't want to get into Fusion360 that deeply at this point. Anyway, here's a wobbly video of the process. 20220101_211220 by Timothy Froud, on Flickr Out of interest, here's the G-Code for that. I've used the same technique that I used for incrementing angles on the Injector cones. This time I'm incrementing the X-axis by 0.25mm for each call to the Sub-Program. Each call of the Sub-Program machines the four sides. I've done the deeper cuts in two bites, and the shallow ones in one. Each then takes the final 0.2mm to clean up the face with the minimum deflection. (Tapered top spacer using 4th axis) (and 8mm cutter and 16mm stock) G90 (absolute positioning mode) M3S1000 G1X0Y12.5Z10F500 M98 P1234 L324 (Repeat subprogram 81mm/0.25 times) M5M30 O1234 (Rough and finish one X increment) (on all four sides) G90 (absolute positioning mode) Z10F500 Y12.5 A0F10000 (Bottom surface) Z5F500 Y-12.5F100 Z2.684F500 Y12.5F100 Z2.484 Y-12.5F200 (Back surface) Z5.7F500 A90F10000 Y12.5F100 Z5.5 Y-12.5F200 (Top surface) Z5F500 A176.28F10000 Y12.5F100 Z2.361F500 Y-12.5F100 Z2.161 Y12.5F200 Z5.367F500 (Front surface) A263.2F10000 Y-12.5F100 Z5.167 Y12.5F200 Z10F500 (Get clear) G91 (incremental positioning mode) X0.5 (increment X to next) !!! should have been 0.25 !!! G90 (absolute positioning mode) M99 (Return from Sub-Program)
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jasonb
Elder Statesman
Posts: 1,209
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Post by jasonb on Jan 2, 2022 7:12:10 GMT
Don't you have a tailstock to go with that dividing head? It would have supported that long stick out so you could take heavier cuts. Just make it a bit overlong so the ctr hole can be cut off at the end.
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Post by Roger on Jan 2, 2022 11:38:42 GMT
Don't you have a tailstock to go with that dividing head? It would have supported that long stick out so you could take heavier cuts. Just make it a bit overlong so the ctr hole can be cut off at the end. Yes, I showed it when I was machining the Burrell Connecting Rod. However, that introduces as many problems as it solves. Sometimes there's no alternative, and that's when I'll use it. The issue is that the accuracy of the part relies on the centre height of the tailstock being spot on. That's surprisingly difficult to get right, and since there was another way around it, I opted for that. As usual, there are many ways to do these things.
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Post by Roger on Jan 2, 2022 12:13:47 GMT
So far so good... 20220102_094544 by Timothy Froud, on Flickr ... and then I was alerted to a horrible noise in the workshop and oops! I'd set the number of increments to the correct number for the reduced cut of 0.25mm for each step, but forgot to change the step from 0.5mm to 0.25mm! Doh! That will explain why I was surprised that it still wasn't happy when I thought I'd reduced the cut. As always, if you don't understand something, it's a good idea to stop until you do! You live and learn. Anyway, it tripped the 4th axis amplifier, and I managed to stop it doing any more damage. Such is life, it's not a big deal. I'll knock off the rough edges and maybe look out for another set of jaws. Actually, this offers up an opportunity to improve the setup. Now the outside middle set of jews are ruined, I may as well machine them away to a chamfer so as to give more clearance when getting close to the chuck. I'm also tempted to buy an ER16 set for this setup which would also help. I don't get upset by these mishaps, it's just part of life and you can't undo it. If you can turn it into an advantage then all the better. 20220102_105935 by Timothy Froud, on Flickr Anyway, I finished that off by adding the holes and parting it off, and it's a lovely fit, so I'm pleased with that. 20220102_115951 by Timothy Froud, on Flickr Now that I've changed the cut to 0.25mm as intended, you can see that this video shows it making short work of the job, even with that huge overhang. 20220102_115710 by Timothy Froud, on Flickr
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Post by Roger on Jan 2, 2022 18:33:48 GMT
The second one didn't take that long, so here it is getting the clearance holes for the fixing bolts. I'm supporting the end else it's too springy. 20220102_173048 by Timothy Froud, on Flickr So here they are finished. That turned out to be a fairly easy way to make these. 20220102_182850 by Timothy Froud, on Flickr
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Post by Roger on Jan 3, 2022 20:59:52 GMT
There's another pair of Lamp Irons on the top of the Cylinder Cladding, one on each side, to store the Lamps when not in use. They're Welded on, but I'll rivet them and file them flush. 20180110_134618 by Timothy Froud, on Flickr I'm drilling the tight inside corner so it gives the cutter an easier time when it comes to finishing. It's 1.3mm diameter, so the 2mm diameter roughing cutter won't rough that out. I drilled it 1.2mm with a PCB drill, but I don't have 1.3mm so I used a HSS drill and the pin chuck for that. 20220103_105516 by Timothy Froud, on Flickr It's roughed out to 6mm depth with a cut width of 0.2mm to give it a bit of clearance when it's up to its neck. 20220103_163130 by Timothy Froud, on Flickr Then it's finished off with a 1mm PCB Carbide Burr which seems to work better than a 2 flute. I think it's because it's more rigid, so it's less prone to breakage. The 'flute' length is 10mm , so it's pretty slender. I'm taking just 0.1mm depth of cut and 15000RPM to make sure it doesn't break. 20220103_164354 by Timothy Froud, on Flickr You can get an idea of how that looks in this wobbly video... (it sounds terrible, but that's just because the phone microphone is up close and personal) 20220103_164415 by Timothy Froud, on Flickr Anyway, the first one has come out really nicely, so it's on to the second one before I've got to get back to commercial work. 20220103_190757 by Timothy Froud, on Flickr
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Jan 3, 2022 23:43:49 GMT
Great picture of a lamp iron on 1501 Roger, thanks. Another example of Swindon’s decidedly ‘agricultural’ blacksmithing by the look of it, though the skilful welding onto that thin sheet doesn’t seem to accord with the rough-and-ready installation layout. The photo shows the lamp irons in front of the outside steam pipes, so these are for the ‘spare’ lamps, not the ‘working’ ones. A trivial note for others; these irons seem to have migrated to different positions on different members of the class during their lives. On mine (which will be no 1500 early in its life) I fitted them behind the steam pipes; I can’t remember why, it must have been on a photo. ISTR someone saying that in this early position they would have got covered in oil if the snifter valves leaked.
Gary
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Post by Roger on Jan 4, 2022 7:30:35 GMT
Great picture of a lamp iron on 1501 Roger, thanks. Another example of Swindon’s decidedly ‘agricultural’ blacksmithing by the look of it, though the skilful welding onto that thin sheet doesn’t seem to accord with the rough-and-ready installation layout. The photo shows the lamp irons in front of the outside steam pipes, so these are for the ‘spare’ lamps, not the ‘working’ ones. A trivial note for others; these irons seem to have migrated to different positions on different members of the class during their lives. On mine (which will be no 1500 early in its life) I fitted them behind the steam pipes; I can’t remember why, it must have been on a photo. ISTR someone saying that in this early position they would have got covered in oil if the snifter valves leaked. Gary Hi Gary, I'm not sure if the lamp irons are forged or cast, personally I'd opt for them being cast. It's hard to reconcile the huge weld fillet with the thin sheet, I think something is missing in that. Maybe there's a backing plate there? In this shot you can see the position of the 'Stop' on the Lamp Irons, and clearly it's intended to rest against the bracket on the Lamp, not the base... 20140204_112717 by Timothy Froud, on Flickr ... However, on this shot you can clearly see that it's not being used that way. So my best guess is that the LH and RH sheets have been swapped over to move the Lamp Irons to the front as you suggest. It's a bodge, but that's how it is, so that's how I'm making it. IMG_8085 by Timothy Froud, on Flickr
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Post by 92220 on Jan 4, 2022 9:43:12 GMT
Hi Roger.
The lamp irons are welded. I blew your photo up and it is possible to see the weld on the side of the lamp iron, on the end of the small support strip, that goes across at the bottom of the vertical leg.
Bob.
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Post by Roger on Jan 4, 2022 12:07:38 GMT
Hi Roger. The lamp irons are welded. I blew your photo up and it is possible to see the weld on the side of the lamp iron, on the end of the small support strip, that goes across at the bottom of the vertical leg. Bob. Hi Bob, You have keen eyesight! The only Works Drawings I have of them gives no hint as to how they are supposed to be made. There's a definite fillet and radius shown under the 'Stop' which hints that the intention is for them to be a casting. The vertical part is tapered, both in thickness and on the width. That's a real pain to make from sheet. Who knows. It's possible that they were made in a variety of ways, since the bases are all different. Personally, I'd have cast the vertical double tapered part with the 'Stop' as one piece, and then welded on whatever mount was required.
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Post by 92220 on Jan 4, 2022 14:30:22 GMT
Hi Roger. I've just blown up the photo, in your post, above, that shows the front of the loco. The lamp iron on the right hand side of the photo (left hand of loco), seems to show as a casting. The lamp iron of the left of the photo (right hand side of loco), appears to be a welded assembly. If you also look on page 739 of your thread, the same right hand (loco right) and it appears to show it as a welded iron. I think it must be a repair job, and the cast ones, as you surmise, are what was fitted as new. Bob. Edit: Here is that photo:- Lamp iron on 1501 by Robert Shephard, on Flickr
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Post by Roger on Jan 4, 2022 14:35:55 GMT
Hi Roger. I've just blown up the photo, in your post, above, that shows the front of the loco. The lamp iron on the right hand side of the photo (left hand of loco), seems to show as a casting. The lamp iron of the left of the photo (right hand side of loco), appears to be a welded assembly. If you also look on page 739 of your thread, the same right hand (loco right) and it appears to show it as a welded iron. I think it must be a repair job, and the cast ones, as you surmise, are what was fitted as new. Bob. Hi Bob, That makes sense, thanks for looking at that for me.
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Post by 92220 on Jan 4, 2022 14:43:55 GMT
Hi Roger.
I went back into my blow-up of your front photo, above, and blew each of the lamp irons up as far as I could, before losing definition. The left hand (loco) iron is definitely a casting, as is the one in the middle. The one on the right hand side of the loco is definitely a welded lamp iron. What looks like s curve underneath the lamp support stop, is actually a weld fillet, which becomes clear when the photo is blown up as far as it can go. You were right in thinking they were cast, as originally fitted.
Bob.
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Post by Roger on Jan 4, 2022 15:00:22 GMT
Hi Roger. I went back into my blow-up of your front photo, above, and blew each of the lamp irons up as far as I could, before losing definition. The left hand (loco) iron is definitely a casting, as is the one in the middle. The one on the right hand side of the loco is definitely a welded lamp iron. What looks like s curve underneath the lamp support stop, is actually a weld fillet, which becomes clear when the photo is blown up as far as it can go. You were right in thinking they were cast, as originally fitted. Bob. Hi Bob, I presume they're cast in Steel as originals, since it's not really viable to weld Cast Iron. And before anyone jumps in to say that you can weld Cast Iron, you sort of can, with pre-heating, special rods, and peening the weld at each stage. However, you never get a joint as strong as the original part, and I very much doubt if anyone would go to such lengths for a Lamp Iron. The issue with welding Cast Iron is the contraction when the weld solidifies and shrinks. All of the above are attempts to reduce these entrapped shrinking forces, but you can't eliminate them entirely. Sure, it doesn't need to be that strong, but they would surely be way too easy to just snap off without much effort.
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Jan 4, 2022 16:10:52 GMT
Hi Roger. I've just blown up the photo, in your post, above, that shows the front of the loco. The lamp iron on the right hand side of the photo (left hand of loco), seems to show as a casting. The lamp iron of the left of the photo (right hand side of loco), appears to be a welded assembly. If you also look on page 739 of your thread, the same right hand (loco right) and it appears to show it as a welded iron. I think it must be a repair job, and the cast ones, as you surmise, are what was fitted as new. Bob. Hi Bob, That makes sense, thanks for looking at that for me. In fact, we are now looking at the ‘working’ lamp irons, not the spares. The reason this makes a difference (and apologies that this goes even beyond rivet-counting!) is that on the 15xx (and uniquely to that class) the RH front lamp iron was a ‘special’, and had to be built up extra high, with the base pointing the ‘wrong’ way. This is because there was very little in the way of hardware to bolt the base onto, and standard GWR lamp irons always have the base projecting to the left when viewed with the lamp face-on, IYSWIM. This can’t be seen in the picture, but Bob has spotted the welding that was needed to extend the standard item. I think the LH iron was also stretched vertically on some locos, (on others, or at different times, there was a thick cast spacer block for it to stand on) but the base was in the normal orientation. This accounts for the welding Bob has spotted, and explains why the ‘spare’ irons only seem to be welded at the base. I don’t know for sure how they were made, but I’ve always assumed they were drop forged. They were made in large numbers, so this seems a more logical way to build an item that needed to be smooth as well as strong, not for the weight of the lamps but to cater for knocks and bumps with heavy objects that railways had in abundance. Hope this helps somebody Gary
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nonort
Part of the e-furniture
If all the worlds a Stage someone's nicked the Horses
Posts: 277
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Post by nonort on Jan 4, 2022 17:47:31 GMT
Having looked at a few lamp irons on Pannier tanks for my own engine I came to the conclusion that they were forged? Just a thought it would make them easy to make and very easy to be modified and weld into various positions. The panniers were of course made by many manufactures.
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