Lisa
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Post by Lisa on Jan 13, 2019 19:06:41 GMT
LBSC designed Tich with 3/32" (2.38mm) thick frames, but I've opted for 3mm. There's two reasons for this, the first being that it's what I have, and the second being that I figure a little extra weight would be an advantage. The frames are therefore a little closer together, so that the overall width is the same. A bit of elbow grease to cut the frames from some plate, then they were bolted together and put in the mill. The bolt holes at the end were put where they'd be cut off, while the larger ones for clamping to the mill table were inside the horns. Of course, the frames are 327mm long, and I've only got 220mm of table travel, so cleaning up the top edge took two goes and a bit of fiddling with the DTI to get the frames square twice. Then with the dials zeroed to the top and front, the drilling began; this would be easier with a DRO, but as long as one allows for backlash, it's not too bad. First moving to the nearest lower multiple of 10 handwheel turns, means one can use a ruler to check that no miscounting occurred, as any variation is plainly obvious. One of the advantages of drawing the part in CAD first, was that I could then pull the coordinates of each hole out and put them on the drawing, which simplified getting the holes for the cylinders and motion brackets in the right place. I also spotted the top corners of the horns at this stage, as a guide for milling them. After milling out the horns, I removed the sideframes from the mill, and gave them a cleanup. Then hacksawed and filed to final shape, before unbolting them; having put bolts into some of the holes as I was drilling them. Then of course I balanced things in place for a look; onto the angles to actually bolt and rivet things together next. Also, a size comparison, with Tich's chassis on top of Blowfly's chassis:
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Lisa
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Posts: 806
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Post by Lisa on Jan 13, 2019 18:13:19 GMT
Having reached the goal of getting Blowfly running on air, I've decided to let it sit in the background a bit while I work on something I can actually afford to finish. So I've started on a 3½" gauge Tich (small boiler). It's a design that's fascinated me since I was a child, and with a few exceptions (cylinders being the most obvious), I'm pretty sure I already have most of what's needed to build it (including materials for the boiler). A boiler for Blowfly is wildly out of my budget for a variety of reasons, whereas Tich's boiler is small enough (and cheap enough), that I'm quite happy to build and test one on my own, and if I ever need to I can just make another for club running. I'd considered building a Minnie traction engine, but I just prefer loco's. Thus my general aim is to focus on getting a running Tich, while still being able to fiddle about with fittings and bits for Blowfly as the mood takes me. So I've made a start on Tich. First was the bufferbeams. One thing I'm doing with Tich is redrawing everything in metric - a good chance to learn to use OnShape - mostly this is just a matter of converting an imperial measurement, and changing bolt/rivet/pin sizes to the nearest metric size. There is however, also the odd place where I'm rounding to an equivalent but 'neat' metric value, so the bufferbeams are 20x20x3, which is a little larger than ¾" (19.05mm). I used of a lump of aluminium as a fixture in the mill, then set about drilling holes, and milling the beams to size. Scribbling down the dial readings to help with repeating for the second one. That all went rather well, and flipping them upside down meant I could square up the corner of the angle. The angle I have is a touch over size, which also meant I could square up the bottom edge nicely. A bit more hacksawing and milling meant the bufferbeams were done, with the exception of the coupling holes not being opened out to squares; partially because I'm trying to find the tiny square file, and partially because I might oversize the rear hole for a clevis to couple up to a driving truck with.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 13, 2019 16:37:13 GMT
Unfortunately when you are running a scheduled passenger service and there are 3 or more trains behind anxious for you to depart the Station you simply just don't have the time to wait for the injector to cool down. This is how we did it when running commercially; when delays mean less pay one looks for the most reliable method, which was this. Also similar to what the fullsize used to do in places; they'd pull up next to a windmill and dump buckets of cool bore water on the injector till it picked up.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 13, 2019 12:54:05 GMT
A bag of ice cubes into the tender water on a very hot day ??...... Save your ice cubes, just hold one against the injector and count to 10, it'll pick up.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 12, 2019 9:47:06 GMT
Without seeing a picture of the step... I think it's the step up from path to concrete slab in the second picture of the first post in the thread.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 11, 2019 18:41:08 GMT
That's true if also used as a workstand. Perhaps that could be overcome by moving it to one side and spaced down a bit. I'm sure there are advantages to both screw positions. It's probably a case of asses the advantages and disadvantages of each position and choose the one that has the most pluses. It just occurred to me that putting the handle at the other end would mean there's not a threaded rod running the full length, thus solving the problem.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 11, 2019 16:43:40 GMT
Hi David. That's a very neat jacking trolley. Like Eddie suggested, the handle underneath the rails would have been easier to operate. It wouldn't be very difficult to swap it over, even now. It looks as if the jacking frame is almost mirrored top and bottom so it should be very easy to move it up to the top. Bob. With the thread at the top it would then be more awkward to use as a work stand, due to the big threaded rod between the rails. As-is it's a bit more of a multipurpose stand, rather than only a jacking trolley.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 11, 2019 9:57:47 GMT
Now after all the wonderful electronics of the Weigh in. The way to a perfect pitch is to borrow the sound card technology from the O Gauge Boys and Girls and do it with a wisp of Steam issued from the right place and a micro switch behind that activates the whistle stored in the little black box! 2 micro speakers on the driving trolley and we are off to a winner? David and Lily. "Nice loco, shame about the sound," is my usual thought on hearing electronic/recorded sounds. Even with properly set up undistorted sounds, they still sound unnatural to my ears. Whether it's the sound not suiting the scale of the model, background noises in the recording (not like they can put a fullsize loco in a sound studio to record it), 'chopped' beginnings and ends to the sounds, the volume not matching the sound effect, obvious repeating of a recording, sounds not synchronised to the actual loco, recorded sounds blocking out real sounds, or a combination of these, it's always so blatantly artificial. Similarly, there was a clock tower on a shopping centre near me a while back, it had full westminster chimes provided electronically from a recording; there were so many complaints that the sounds were removed within a couple of months.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 10, 2019 13:19:29 GMT
Just found an old police whistle in my great granddads old locomotive (3.5” Maisie) works perfectly lovely sound, funny but a good bit of lateral thinking Dad's first loco, a 3½" gauge QR B12, had a scout whistle soft soldered to a union. It was a bit shrill, but worked fine on steam... I suspect I've still got it in a box somewhere actually.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 10, 2019 10:49:14 GMT
The 'today' part of this is finding the photo, otherwise it's more 'what I did in 2003-ish'. Yours truly running dad's sweet pea on the track around the house, but if you look carefully I'm also 'double heading' with the rolling chassis of blowfly coupled up behind.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 10, 2019 10:35:15 GMT
While looking for some pictures earlier, I came across this shot of the aforementioned 3½" gauge battery electric loco, with a 5 year old yours truly driving. Judging by the colour, this is the original cardboard body that didn't survive a storm. This would be about 1986/87.
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Lisa
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Posts: 806
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Post by Lisa on Jan 10, 2019 10:30:34 GMT
We had similar issues with moving loco's around when running commercially; there were a couple of jobs where we had to park a significant distance from where we'd have to set up the track, and in some cases had to carry everything along winding walkways, sometimes with steps, to get to the site. Dad's solution was a 2-wheel trolley using bicycle wheels, which allowed the loco to be rolled on, then moved around easily. Being two wheels meant the loading end could be put at any height easily for rolling the loco on or off, whether it was ground level for the track, bench level for maintenance, or waist level to get the loco in or out of the van. Also some bricks or a milk crate under the end would hold it level, giving a mobile work stand. I had a bit of a hunt for pictures, and of course there's no great picture of the trolley on it's own, but it can sort of be made out in the background of these: A dusk shot of our portable track setup, the loco trolley can just be seen in the middle of the track. It's in the background here, connected to the end of the track. As above, but I've messed with the brightness and contrast to hopefully show it a little better.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 9, 2019 3:42:46 GMT
I recognise that Dick McKenna drawing, I have that one as well and my plan is to make this for my JJ 060 one day. They sound nice not like some that squeak as if you had steeped on Lorrikeet's toes :-) Yeah, that's the loco; this was on dad's switcher. I've seen that whistle soothe a crying baby to sleep!
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Lisa
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Posts: 806
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Post by Lisa on Jan 8, 2019 10:28:32 GMT
In sound terms it's like two people harmonising versus a solo, or playing two keys at once on a piano; it gives a much richer sound, and can also seem louder at the same decibel level (important, for an audible warning device). As for the purpose of a multi-chime whistle, rather than two or more single chime whistles, I'd imagine it just comes down to less parts and simpler plumbing, at the expense of a little more complexity in making the whistle bell.
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Lisa
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Posts: 806
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Post by Lisa on Jan 8, 2019 9:25:19 GMT
If you go in the opposite direction to what Pete suggests, a small opening in the lower chamber would allow steam to gradually build pressure within, once the steam reaches sufficient pressure to lift the clanger arm it does so, which opens the valve and vents the steam to atmosphere, then the pressure drops, the clanger falls, and the process starts over.
As long as the steam enters the lower chamber at a slower rate than it can exit, then you'll get repeated ringing of the bell.
I'd guess the large passage on the left would be piped away elsewhere so that the exhaust venting doesn't affect the bell.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 8, 2019 8:50:22 GMT
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 7, 2019 21:31:26 GMT
I don't have a picture to hand but I would say that my relic would be my Unimat 3 which my father bought for me at Wembley ME, IIRC that was 1983 so 36 years ago this month. I still have it and plan to make good use of it when making the various boiler fittings. When I was at secondary school in the 70's I had Metalwork, Woodwork and Technical Drawing classes. I made a working submersible submarine in metalwork, so that was my first pressurised vessel, the second and last being the vacuum reservoir for Doncaster. In woodwork, my project was a 'racing car'. When it came to choosing my options I had to choose one from those 3, I chose TD as I found it a challenge and was pretty good at it. It's a real shame that such classes have been confined to history these days... Pete We had technical drawing, though it was called something else that I can't recall, and also woodwork. Woodwork we actually did some things in, I've still got a footstool I made around here somewhere. Technical drawing, or whatever it was called, was all done with pencil, paper, and trisquare; on the first day the teacher gave us a little introduction which was basically "all this will be done on computer by the time you graduate, and I'm sorry but I can't teach you any of that, so don't bother taking the class for a second year, you won't learn anything you'll actually use."
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 7, 2019 17:09:03 GMT
I regularly use a tap wrench I made in the school metalwork lessons in 1965. I went to Secondary school in the 90s and we didn't touch metalwork once. Just built Oxo cube holders and charity boxes out of MDF. My apprenticeship was an improvement but I do wish I'd had a go in school. I was in secondary school in the 90's too; all the metalwork we did was sheet metalwork. Basically we just made various sizes of little boxes that were either rivetted or tack welded together. I did more interesting metalwork at home.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 6, 2019 11:41:03 GMT
I wonder if some people lose momentum through choosing the wrong model to start? "Start off with something nice and simple to cut your teeth" - and you spend a few years working on something that you don't really want when it's finished. Be adventurous, be ambitious, and start something that you really want to build and own and run! Definitely, Blowfly being a prime example; that's why 25 years after starting it I've only just got the chassis running on air. When I first seriously decided to build a steam loco, I wanted to build a 3½" gauge Tich, but considering we were running commercially at the time a 7¼" gauge Heidi II was also appealing. However I was talked into Blowfly because we already had 5" gauge, it'll pull a load, it's still easily portable, it was a simple design to start with, and we already had the plans (AME magazines). So I made the frames, lost interest, and started on Heidi II. As it turns out I didn't finish Heidi either, ultimately deciding it was too big, I sold her off just needing pipework, paint, and a cab roof. Then I poked at Blowfly a bit more, so I had a rolling chassis, then for a variety of reasons shoved that under a bench for the next ten or so years. So while I think 'start simple' may be good advice, 'find something simple that interests you' would probably be the better advice.
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 6, 2019 11:17:55 GMT
Lurking under a bench is these, the wheels are the last remnant of a 3½" gauge battery electric loco that dad made for me when I was 5 or so, and replaced the original wooden wheels that I wore out in a few months.
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