barlowworks
Statesman
Now finished my other projects, Britannia here I come
Posts: 877
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Post by barlowworks on Feb 6, 2019 8:10:26 GMT
If you are working with MDF please remember to wear a face mask and keep the work area clean. MDF fibres in the lungs are to be avoided at all costs. Links with the big C apparently. Be safe.
Mike
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Post by Roger on Feb 6, 2019 8:16:53 GMT
Roger -Many thanks for the MDF suggestion, I think that might be the answer... It comes in varying densities if I remember correctly, and I recall some of the heavier stuff is pretty tough. If I can track down some suitable offcuts, that might well do the trick. Also thanks for the suggestions on working the brass. I wish I hadn't already seen your results first though; I fear you might have set the bar too high! :-) Best wishes to all Gary Hi Gary, I forgot to mention that for all flanging operations, I personally would use a stout cover plate that goes right to the start of the bend, bolted firmly down or located accurately and clamped on. As soon as you strike the plate to start the bend, it wants to pivot on the corner and lift the flat face, so it makes life much easier if you can prevent that from happening at every stage. Since the middle is cut out anyway, you can easily bolt through where the hole for the boiler barrel goes through. When I bought the Brass and handled it for the first time, I was convinced I'd made a mistake, I couldn't imagine how anything that hard could be formed. However, once it was red hot, I could hear how dull it sounded, so I knew I'd be able to do it hot, even if it wasn't possible cold. As it happens, it was remarkably easy. Do it a little at a time and you won't have any trouble. Trim the excess so you're not fighting against that along the way. Just keep on annealing and slowly plugging away, and you'll get there in the end.
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Post by ilvaporista on Feb 6, 2019 9:27:54 GMT
Whilst on the MDF formers another quick tip that I used was to laminate thicknesses together. I made a former for a rear smokebox plate for my 5" Hunslet. Double formed with the front supporting the smokebox wrapper and the rear formed the other way to support the boiler. Made in 2.5mm copper sheet. The outer shape was one 10mm thick and one 18mm. Glued and screwed together. For the radius on the edges I just ran round with a router bit with a ball bearing guide along the edge. The boiler support was done by boring a hole and again rounding of the edges with a router bit. Use a backing plate and make it as big as possible as it also stops wayward blows marking the work. Next time I will do the inner hole first as holding the plate with the flange and not much flat area to clamp was a bit of a struggle. Thanks for the tip about aeroplane dope. I must try that next time. Edit: Dust mask and vacuum cleaner when using MDF. The dust gets everywhere and is said to be pretty harmful. If you have not seen roundover router bits, here is a link. goo.gl/images/vtd28i
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Post by Roger on Feb 7, 2019 0:12:55 GMT
Next up is the threaded adjuster for the coupling. This is the short end which has the swivel and bearing... 20190205_190710 by Anne Froud, on Flickr .. which is transferred to the tilting rotary table and clocked up to the axis of rotation. This is the roughing operation with an 8mm cutter... 20190206_091930 by Anne Froud, on Flickr .... followed by a 3mm one... 20190206_100824 by Anne Froud, on Flickr .. then a 1.5mm diameter one. I didn't notice, but at this stage it's slightly undercut which is a bit annoying. 20190206_110715 by Anne Froud, on Flickr Then it was turned over and rotated to machine the lug, first with a 2mm cutter... 20190206_142517 by Anne Froud, on Flickr ... and then with a 1mm PCB burr. 20190206_165329 by Anne Froud, on Flickr Finally, the shackle and nut were fitted to find the correct location for the split pin hole. It was started like this, then the nut removed to drill it right through. That's a 0.8mm drill. 20190206_171855 by Anne Froud, on Flickr The split pin fits nicely. 20190206_172853 by Anne Froud, on Flickr The bar is EN8 so it's not particularly nice to machine. This amount of overhang isn't ideal, so I took it slowly... 20190206_205600 by Anne Froud, on Flickr ... plunging in repeatedly to about 6mm diameter to remove the bulk of the material which it was still supported by the full diameter. This is better than gradually reducing the diameter in my opinion. 20190206_210412 by Anne Froud, on Flickr The diameter was cleaned up while supporting the end in the female live centre, then parted off 4mm over length so I can put a centre in the end for the next operation. 20190206_210947 by Anne Froud, on Flickr The ER32 collet is just short enough for the part to stick right through.... 20190206_212303 by Anne Froud, on Flickr ... then a threaded bush was made to screw the previously machined end into. Here it's supported by the centre, ready for turning to the final diameter. The large radius tipped tool is to provide an nice strong end to the threaded portion like it is on the real thing. 20190206_215910 by Anne Froud, on Flickr The tailstock die holder really comes into its own for this kind of job. 20190206_222048 by Anne Froud, on Flickr The large drill chuck was just long enough inside to grip the body so I could unscrew it. I should have used some paper between the part and the jaws really, I'll do that on the next one. 20190206_222745 by Anne Froud, on Flickr I already had this threaded bush which is ideal for holding the thread while sawing and turning to length. I have one or more of these for just about every size of thread. I keep them with the taps. 20190206_223827 by Anne Froud, on Flickr 20190206_224857 by Anne Froud, on Flickr It still needs a bit of adjustment and finishing, but it's nearly right. Just the bob weight and handles to do. 20190206_225152 by Anne Froud, on Flickr
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dscott
Elder Statesman
Posts: 2,440
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Post by dscott on Feb 7, 2019 0:54:11 GMT
Honestly this is the best one I have ever seen! The blending of the ends is superb. All this CNC is making me want to get on with my version! I spent an hour mig welding up holes in the second set of frames on converting them from Speedy to finescale 1500. Yes the Club has a new machine TINY!!! Thursday is angle grinding. Then just clamp frame one to it and use as a template!
David and Lily.
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Post by delaplume on Feb 7, 2019 16:24:30 GMT
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Post by Roger on Feb 7, 2019 17:11:35 GMT
Hi Alan, I guess unless you know what they are for, the aren't much use really.
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Post by ettingtonliam on Feb 7, 2019 21:39:28 GMT
At least the ex Reeves ones I bought off them had the identity of the loco and the plate thickness hard stamped on the edges of the formers. Essential really, when you think that they a 'library' of over 200 sets of formers at one time. Would have made these ebay ones more saleable too.
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Post by Roger on Feb 7, 2019 23:13:50 GMT
This is one of the forked pieces that forms the hinge for the adjusting handle with the bobweight on the end. There are two machining operations, one with the quill locked to machine the profile and another to drill the hole with the quill unlocked. Yes, I could use a pecking cycle to drill the hole, but I prefer to do these by hand. The consequence is that I need to clock it up for the drilling operation with the quill unlocked because there's roughly 40 microns movement right to left when that happens. 20190207_092339 by Anne Froud, on Flickr This is a 1mm PCB burr being used to machine the 1.2mm wide slot. It's a totally unsuitable cutter for the job, far too flexible and the wrong kind of teeth, but at £1 a go, I'll do it slowly and it will be fine. 20190207_133834 by Anne Froud, on Flickr Again, the end position of the bar was set with the wobbler between the locked and unlocked quill operations. The hole here is 1.2mm diameter for the handle location and there's not much room either side, so it needs to be set up accurately. 20190207_135534 by Anne Froud, on Flickr I parted these off with a 1.5mm wide HSS parting tool, it's more gentle and easier to get a smaller 'pip' when it finally comes off. The shaft is 1.6mm diameter Silver Steel which was held in a 1-2mm ER32 collet in the lathe for turning the register. It's a press fit so it stays put while Silver Soldering. 20190207_205038 by Anne Froud, on Flickr I put 3/4 of a turn or 0.5mm Silver Steel wire up against the joint and heated them up... 20190207_220227 by Anne Froud, on Flickr ... which looked ok... 20190207_220627 by Anne Froud, on Flickr ... until it was cleaned up. Clearly that hasn't bridged the joint. 20190207_223605 by Anne Froud, on Flickr Here is't dangling from the 'Vice on a stick' with the smallest scrap of 0.5mm Silver Solder on the joint. 20190207_223910 by Anne Froud, on Flickr One of them bridged without a problem, the other needed a second go. There's way too much on there now, but that can be machined off and tidied with a file. So far, so good. 20190207_230024 by Anne Froud, on Flickr
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Post by Roger on Feb 8, 2019 18:40:09 GMT
The bob weight for the coupling adjuster handle is spherical with flat sides. This is the 3D model of the Form tool for creating the sphere and the small parallel diameter in one operation. You can see the angled plane that the desired profile is drawn on. The projected cut is drawn on the X/Y plane but it's actually machined at 10 degrees on a tapered wedge in the vice. Bobweight form tool by Anne Froud, on Flickr I'm using one of the many 5.5mm 3-flute cutters found at the ME Show in the Midlands. 20190207_231307 by Anne Froud, on Flickr This is an M5 tapped hole going in to hold the support that's shown next. 20190208_093428 by Anne Froud, on Flickr The problem with a Form tool like this one is that the diameter that's supporting it is very small. That means there's every likelihood that the part will climb up over the tool when it's fully engaged. 20190208_104110 by Anne Froud, on Flickr The solution is to turn the diameter of the blank to be the same as the finished size of the sphere, then use a support that rests precisely on the top of the bar while the cut is being made. 20190208_112741 by Anne Froud, on Flickr I didn't allow enough clearance on the base of the clamping piece, you can see it's been filed back in this shot compared to the last. 20190208_113816 by Anne Froud, on Flickr Anyway, I've never tried that idea before, but it worked like a charm, no chatter and no tears. It's not very nice material, I don't think it's Free Cutting Mild Steel. 20190208_113927 by Anne Froud, on Flickr Again, there's not much support, but using a new cutter and restricting the depth of cut to 0.2mm for each pass, it's possible to machine it without making another fixture. 20190208_180119 by Anne Froud, on Flickr And here's a piece of 1.6mm Silver Steel for the pivot being reduced to 1.2mm diameter. 20190208_161927 by Anne Froud, on Flickr
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Post by Roger on Feb 8, 2019 21:14:23 GMT
I've parted these off so they're long enough to hold and clock up in the lathe chuck. 20190208_194100 by Anne Froud, on Flickr First I faced them off and then measured the overall length then subtracted the radius of the ball. I want the shaft to go into the centre. Then it's just a matter of drilling to the right depth... 20190208_200533 by Anne Froud, on Flickr ... then parting off. 20190208_202225 by Anne Froud, on Flickr A quick tidy up with needle files and then it's cleaning up time with meths and then a dab of Loctite to hold them in place. 20190208_210744 by Anne Froud, on Flickr
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Feb 8, 2019 21:32:54 GMT
Fabulous work!
Don
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Post by Roger on Feb 9, 2019 15:33:13 GMT
Compressing the drawbar spring and at the same time inserting the retaining pin proved to be really tricky, so rather than struggle, I decided to make a simple clamp arrangement. 20190209_114853 by Anne Froud, on Flickr I need to be able to do this while it's on the turning frame, and that means there isn't room to put anything over the end of the drawhook. The cap screw locates in the hook 'U' shape, and a pocket for the spring retainer has a very shallow rim to press against it. 20190209_114909 by Anne Froud, on Flickr I'd definitely make this longer if I was to make it again, but it's worked out ok. There's about 2.5mm of travel on the spring which is pretty strong. Hopefully that's going to be satisfactory. 20190209_114956 by Anne Froud, on Flickr Back to the drain cock mechanism, this is one of the two supports that keep the long actuating rod in place as it goes along the length of the frame. 20190209_122559 by Anne Froud, on Flickr It's quite thin, so a screwdriver pushed by hand in the right place was enough to form the shape. 20190209_122714 by Anne Froud, on Flickr 20190209_123417 by Anne Froud, on Flickr 20190209_143644 by Anne Froud, on Flickr 20190209_144152 by Anne Froud, on Flickr 20190209_150232 by Anne Froud, on Flickr
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Post by delaplume on Feb 9, 2019 15:59:10 GMT
Compressing the drawbar spring and at the same time inserting the retaining pin proved to be really tricky, so rather than struggle, I decided to make a simple clamp arrangement. 20190209_114853 by Anne Froud, on Flickr I need to be able to do this while it's on the turning frame, and that means there isn't room to put anything over the end of the drawhook. The cap screw locates in the hook 'U' shape, and a pocket for the spring retainer has a very shallow rim to press against it. 20190209_114909 by Anne Froud, on Flickr I'd definitely make this longer if I was to make it again, but it's worked out ok. There's about 2.5mm of travel on the spring which is pretty strong. Hopefully that's going to be satisfactory. 20190209_114956 by Anne Froud, on Flickr Back to the drain cock mechanism, this is one of the two supports that keep the long actuating rod in place as it goes along the length of the frame. 20190209_122559 by Anne Froud, on Flickr It's quite thin, so a screwdriver pushed by hand in the right place was enough to form the shape. 20190209_122714 by Anne Froud, on Flickr 20190209_123417 by Anne Froud, on Flickr 20190209_143644 by Anne Froud, on Flickr 20190209_144152 by Anne Froud, on Flickr 20190209_150232 by Anne Froud, on Flickr Cracking stuff Roger----- it's that attention to detail that catches the eye !!...........It doesn't matter about the actual size, more importantly does it "look" right ??.... and yours does !! I've just finished some re-wiring on the Chester lathe----cup of cha then it's}--" all hands to emptying the Garden Shed" time whist the sun is still out...... Keep it up matey !! Alan
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Post by Roger on Feb 9, 2019 17:32:03 GMT
Thanks Alan, The drain cock rod supports would have been much easier to mount on the outside of the frame, but that's not how they're done on 1501. That's probably because they are below the springs, but of course I can't put them there with the arrangement that I've got. Still, at first glance, you'd be hard presses to know it wasn't quite right. As you say, looking right is good enough.
Glad to see you're keeping busy too.
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jma1009
Elder Statesman
Posts: 5,913
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Post by jma1009 on Feb 9, 2019 21:10:46 GMT
Hi Roger,
You have done a superb job on the drawhooks and correct GWR couplings. I've made 6 of each over the years, and they are very fiddly to get right and look right.
I was going to post this awhile back, but seemed churlish at the time, but the rear drawhook you might like to re-do for easy removal/ replacement, as many clubs won't allow a standard drawhook for passenger hauling, and require a clevis type coupler on the rear of the loco. The Cardiff club and Kinver have this requirement for a solid drawbar link, as do others. So I made or altered mine to a long screwed end (2BA) protruding into the rear beam, which can be swapped over for a clevis fitting in a few minutes.
If you ever had any thoughts about entering your 'Speedy' in IMLEC, don't have a spring behind the rear coupler, as it mucks up the dynomometer car reading.
Cheers,
Julian
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Post by Roger on Feb 9, 2019 21:27:32 GMT
Hi Roger, You have done a superb job on the drawhooks and correct GWR couplings. I've made 6 of each over the years, and they are very fiddly to get right and look right. I was going to post this awhile back, but seemed churlish at the time, but the rear drawhook you might like to re-do for easy removal/ replacement, as many clubs won't allow a standard drawhook for passenger hauling, and require a clevis type coupler on the rear of the loco. The Cardiff club and Kinver have this requirement for a solid drawbar link, as do others. So I made or altered mine to a long screwed end (2BA) protruding into the rear beam, which can be swapped over for a clevis fitting in a few minutes. If you ever had any thoughts about entering your 'Speedy' in IMLEC, don't have a spring behind the rear coupler, as it mucks up the dynomometer car reading. Cheers, Julian Hi Julian, I was planning on using the design that I think Don posted, whereby there was a link that fitted over the drawhook so it was captive, giving a solid coupling, albeit with the spring still in place. With the spring compressor, it's not impossible to swap it over at the track if it's on a steaming bay, although hardly convenient. I've got a very strong attachment point on the underside of the massive Cab stretcher, the idea being that it's an alternative way to quickly bolt on a coupling arrangement that would come up from under the buffer. I don't like the idea of drilling holes in the buffer to attach a lug. I intend to have a safety chain/wire that can be attached too. Hopefully, among all those options, there will be a solution acceptable to most clubs.
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Post by Roger on Feb 9, 2019 22:25:49 GMT
Although I've already made the bell crank arms for the drain cock actuator where it passes through the frame, I haven't made the rod that links them together. Drain cock bell crank by Anne Froud, on Flickr One end is secured by a press fit with Loctite and the end lightly riveted over for good measure. This end is removable with a hex and retaining nut, both 2mm with the shaft being 2.5mm diameter. There's not much room for all that, but I wanted to keep this all as compact as possible so it doesn't really show. Here I'm using the drill chuck mounted on a mandrel to hold the shaft which is too small to hold in the 3-jaw chuck. The M2 thread was first done in the lathe with the tailstock dieholder, holding it in a 2.5mm collet. These don't come in a standard set for ER32 collets, but you can find them down to 2mm on eBay. I bought a 2.5mm and 2mm one, and I now see you can buy a 1/16" one which might come in handy. 20190209_203017 by Anne Froud, on Flickr Anyway, here's the completed assembly waiting for the Loctite to set before I rivet the end over slightly. 20190209_214003 by Anne Froud, on Flickr
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Post by Roger on Feb 10, 2019 13:56:38 GMT
The pivot shaft still needs riveting over slightly, but other than that it looks ok. 20190210_130034 by Anne Froud, on Flickr The joggle in the rod was done like this... 20190210_104606 by Anne Froud, on Flickr ... with two pieces of 1.2mm sheet with the ends rounded to give the right offset. 20190210_104644 by Anne Froud, on Flickr The end is overhanging so that I can get the wobbler on both sides to find the middle and also the end. A 0.8mm PCB drill was gently used to do the initial hole, then opened out to 1.6mm 20190210_111543 by Anne Froud, on Flickr I'm rounding the ends with filing buttons, so here's the second one being parted off using a rod in the part so I don't lose it when it comes off. I always sweep the swarf away anyway, just in case I do drop it. 20190210_113518 by Anne Froud, on Flickr I've covered the buttons with flux so they don't go black, but that does make them stick to the tile. I've used a small piece so I can dunk the whole lot when it needs quenching. 20190210_122119 by Anne Froud, on Flickr One side done. 20190210_122848 by Anne Froud, on Flickr And this is how the front looks, with the additional support that's not on 1501. Although the rods are all made from Gauge Plate, they're still not strong enough to operate the front link without this. It's going to be tucked away behind a lot of cylinder and crosshead details, so it won't really show. 20190210_134446 by Anne Froud, on Flickr
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JonL
Elder Statesman
WWSME (Wiltshire)
Posts: 2,950
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Post by JonL on Feb 10, 2019 20:27:48 GMT
Your technique for bending small rods is a revelation to me, I normally faff with pliers and don't make a very nice job. It's simple but the results are great, all noted for the future.
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