uuu
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Post by uuu on May 6, 2024 8:18:49 GMT
Aha - I see where you're at.
Every loco is different - I quite like those that need a deep fire, because I find it easier to avoid cold spots. I admire the people that can almost see the grate through the glow. But 2-3cm sounds like a good target. Coal comes in a variety of sizes - small is 0.5-1cm lumps, medium 1-2cm lumps.
In your Harris book you'll see some loco designs - and on some you couldn't have a 5cm fire, as it would come right up to the tubes.
Just musing on equivalence of your boiler to a standard one: The firebox in a loco generates a big proportion of the boiler heat, by absorption of radiant heat from the fire and the gases swirling above it. Hot gases radiate heat! A Simplex boiler has a grate area of 16.2 sq inches, I believe = 105 sq cm. Yours will have 78 sq cm. And the Simplex boiler has a square box above the fire with a lot of gas capacity and surface area. Your sloping sides may have less room. So I'm wondering whether your boiler would make less steam than a Simplex one.
As noted in the Harris book - this boiler is sensitive to water level. You'll need keep the tubes full of water, so the top joints don't overheat.
This could be a fun loco - what does it look like?
Wilf
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uuu
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Post by uuu on May 5, 2024 15:46:28 GMT
In a locomotive boiler, the coal will touch the firebox all round. So it should not matter. But you might be concerned about the robustness of the tubes as you rake the fire, and from the shovel as you throw coal down a quite deep space.
Wilf
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uuu
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Post by uuu on May 3, 2024 7:28:29 GMT
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uuu
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Post by uuu on May 2, 2024 16:28:56 GMT
Yes - a bit of brain fade on my part.
Wilf
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Post by uuu on Apr 30, 2024 16:42:07 GMT
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Post by uuu on Apr 28, 2024 18:59:38 GMT
John the Pump is building Edward Thomas - I think the crankpins are 5/16". I'll be at the Pumphouse on Wednesday and can have a look at the drawings then and let you know. He's doing his rods completely differently (as the real loco is currently arranged - round bushes, not split) so I can't remember the other drawing details.
Wilf
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uuu
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Post by uuu on Apr 24, 2024 16:26:44 GMT
I had a damaged MT2 taper on a lathe - a friend lent me a reamer of the right size and that fixed it. OK, I expect grinding would have delivered a better result, but I was happy with the quick fix.
Wilf
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uuu
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Post by uuu on Apr 15, 2024 18:35:07 GMT
And...
I have wondered on my own loco (Ken Swan's Jessie) why the clacks for axle pump and injector are different. The injector one uses a 3/16" ball and the pump has 1/4". So - if you use O-ring valves, should they also be of different sizes?
Wilf
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uuu
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Post by uuu on Apr 12, 2024 13:12:47 GMT
In the future you could consider upgrading to a three-phase motor with an inverter to provide variable speed. When I've gone this route I've kept my eyes open on ebay for both motor and inverter (separately) to come up cheaply.
Wilf
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uuu
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Post by uuu on Apr 12, 2024 13:09:43 GMT
I would not expect the extra capacitor is related to reversing the motor. It may be you have a "capacitor-start-capacitor-run" motor, that uses one capacitor all the time and another only when starting. This would exhibit a characteristic "click" as the motor slows down on turn-off. See description here: www.electricity-magnetism.org/capacitor-start-capacitor-run-induction-motor/Wilf
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uuu
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Post by uuu on Apr 11, 2024 11:24:16 GMT
I've had a go opening one of your images in IBB. Scrolling down I get a section headed "embed codes" and there's a box with BBCode in it. Copying and pasting into a reply here (not pressing any buttons here - just paste in the code) - I get this : Wilf
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uuu
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Post by uuu on Apr 8, 2024 10:03:09 GMT
Just another thought in support of separate feeds (although as OldNorton says, shared axle/hand pump feed will work):
Boiler feed issues are infuriating. Six people will gather round and each will have a different idea as to the cause. Diagnosis is much easier if you can halve the number of areas to investigate.
Wilf
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Post by uuu on Apr 8, 2024 7:12:55 GMT
Ideally separate - when shared each pump will rely on the others valves to prevent back-flow. So when one pump fails, the other can become ineffective too. But I've seen it done. So I've the boiler is not yet made, I'd add an extra bush - but no point trying to retro-fit one. I've also seen two clacks side-by-side screwed into a single boiler bush - borrowing a John Baguley picture here: Wilf
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Post by uuu on Mar 31, 2024 10:18:16 GMT
My daughter saw a "fidget toy" online - but the cost of shipping from the US was prohibitive - so she asked me to make her one. It was just a switch mounted in a block of plastic, that you could click to keep your hands occupied in meetings etc. Here's what I made: 20240330_124810 by Wilf, on Flickr It's just two blocks of aluminium hollowed out and spigoted together. To dress it up, I added a band of bronze (from John at the Pumphouse) around it. It is pressed together - but with a dab of Loctite to make it more secure. If I made it again, I might use three shorter blocks. You can see scoring on the sides where my milling cutter was a little too short and the area above the flutes (near the joint) rubbed. Wilf
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Post by uuu on Mar 19, 2024 19:05:19 GMT
Myford spindle will take MT2 (if I remember right - I sold mine a while ago) - so no need for a four jaw - just plug in.
Wilf
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Post by uuu on Mar 18, 2024 22:33:33 GMT
Also. Having an MT2 one will fit in both sides of the Myford, Which might be handy.
You can't use an MT2/MT3 adaptor if it's designed for tooling with tangs - or itself has a tang. You absolutely must have the chuck held up by a drawbar.
You can get a screw-in tang to adapt a drawbar tool to fit, for example, the Myford tailstock.
Wilf
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Post by uuu on Mar 18, 2024 22:12:13 GMT
They do come up for sale occasionally - here's one: www.ebay.co.uk/itm/315135882758 It's only got two collets - but they also come up. I wouldn't try to alter the spindle. Much safer to play with the tooling. I don't know how hard the surface of the taper is - I'd be looking to buy what you need. There the "Posilock" chuck, which does the same job: www.ebay.co.uk/itm/285480704662Wilf Edit - I think the small size Autolock chucks may not take collets to fit a 1" cutter. Need to check. You may struggle to find any style of collet chuck that cn fit that size cutter onto an MT2 shank. What you may be able to do is to buy a blank-ended arbour on an MT2 shank and bore it 1" - with a clamping screw. Although I'm struggling to find an arbour with a big enough stub.
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Post by uuu on Mar 18, 2024 13:07:05 GMT
Hello!
I don't think there is a specific topic board - I suppose the Tools and Tooling section would be the best place to start a thread - or just pose a question right here while you have our attention.
I had a Centec, and used an Autolock chuck with it. Decent machine. I've switched over to using ER25 collets to hold tools - they are more versatile, as they can hold plain cutters as well as threaded. I've not found pull-out to be a problem. And you can hold drills in them, gaining a bit more space under the spindle, compared with a drill chuck. My 2A was lacking in space.
Wilf
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Post by uuu on Mar 12, 2024 10:53:55 GMT
Ah - you've hit the snag with this site. You can't upload pictures directly - you have to save them first to an image hosting side like Flickr, and then link them in. There's a thread about it here: modeleng.proboards.com/thread/1627/post-picsWilf
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Post by uuu on Mar 11, 2024 8:47:52 GMT
When fitting motors with a different shaft diameter, I have managed to bore out the existing pulley, or make a bush. Also be aware the foot or flange holes may be spaced differently.
The lathe at the club has a horrible conversion (not done by me) - the whole motor is physically bigger than standard, so the shaft is further away from the foot. This meant enlarging the hole into the belt casing to stop it rubbing - and it doesn't hinge as easily for belt tension adjustment.
Wilf
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