Bill Dawes | 08/10/2013 19:29:21 |
605 forum posts | Slowly slowly making progress. Had a break from decorating today to do a bit more. Stopped my lathe to change a tool, restarted - nothing. No snap crackle bang or funny smells. checked inverter settings and appeared ok, inverter display reads ready to go, Took motor into work today to test and it is ok so back to inverter. Suspect I accidentally selected another parameter so will need to set it up again. Anyway, the real purpose of this is a query on Emma's axle. From the dimensions there is, understandingly, a degree of axial clearance between the wheels and axle boxes. However this also allows axial float with no thrust washer other than the wheel hub touching the axle box (or end of oilite bush) this is a bit alien to me as in my profession of industrial fans, an axle (we call them shafts) has a fixed (located) bearing and a free (non located) bearing. I this float normal on locos? Bill D. |
Stub Mandrel | 09/10/2013 18:06:11 |
![]() 4318 forum posts 291 photos 1 articles | > I this float normal on locos? A showed the underside of my shunter to a model engineer. I apologised for the rattly fits and he said "If it doesn't rattle it won't go". In short, fans don't go round corners, move up and down over bumps, or flex under heavy loads. Neil |
Clive Hartland | 09/10/2013 19:34:32 |
![]() 2929 forum posts 41 photos | I seem to remember allowing 1/16" on the axles of my loco and it has 10 drivers. Its to do with the radius of the tracks and the ability to go around without the rims riding up on the track. So, end float is definitely necessary and as Neil says it needs to rattle a bit, its not a watch so dont make it like one. Clive |
Bill Dawes | 09/10/2013 22:25:10 |
605 forum posts | Makes sense, thanks guys, put my mind at rest. Sorted the lathe problem, motor ok, just reset inverter to factory default and bingo. Must have changed a parameter without realising it. Bill D |
Bill Dawes | 09/10/2013 22:27:40 |
605 forum posts | Meant to ask, does this movement not damage the wheel and/or axle box.? Bill D |
James Sutton | 02/11/2013 00:25:58 |
![]() 18 forum posts 7 photos | I'm also building an Emma Victoria. Which will be the first loco I've built. I recently purchased a 3 1/2" gauge Pamela from a fellow at the club. It was built in 1965 and in its life has won three OMLET, Ontario Model Locomotive Efficiency Trials. The previous owner had it for over 20 years and used it regular. Looking at the wheels, axles and axle boxes there is no damage. I imagine that proper lubrication for running and routine maintenance and care prevented damage. The clearance is there to allow for some flexibility in the locomotive for it to negotiate sharper turns and without it I doubt it could do much more then a straight line. Before my interest in model engineering I was trained as a machinist where tight fine tolerances were required so seeing locomotive gear that almost seems sloppy and loose was strange to me. But after driving around the track I see why it is necessary. A little slack in the parts helps everything run smooth. |
Bill Dawes | 05/11/2013 19:46:56 |
605 forum posts | A problem I had with the axles/axle boxes was getting it lined up. I carefully bored out the boxes on a jig as suggested in the series but the axle was still a bit out of line between one box and the other. I put this down to, my inexperience (mainly) and the fact that you are fitting a relatively accurate machined assembly into a relatively inaccurate horn assembly (ie not a machined item, just two bits of angle rivetted on.) I thought I had fitted these carefully, machining a dummy axle block for the spacing but obviously not good enough. The frames were accurate as I had these laser profiled (even though I felt this was cheating) A bit of filing on clearances, making it a bit rattly, solved the problem but I was left with a feeling of a job not well done or am I expecting too much? Still, slowly pressing on making some of the easy bits (depending what I have the lathe set up for) Plucking up courage to make a start on the cylinders but gaining confidence as I proceed. 'Looking forward' to making the boiler with some trepidation, my efforts with a GLR vertical boiler were a bit fraught but got there in the so hopefully my silver soldering technique is also better. Regards and thanks for replies. Bill D |
Stovepipe | 05/11/2013 21:42:41 |
196 forum posts | Since when did using the best technique (laser profiling) constitute cheating ? I can't pretend to know much about this topic, but using the best technique surely would probably save trouble further down the line. Dsnnis
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Bill Dawes | 05/11/2013 22:07:23 |
605 forum posts | Well it was a bit tongue in cheek but I can imagine some purist would only accept that doing it the hard way by hand is the only 'proper' way. I do have some sympathy with this view as taken to the extreme, model engineering would be simply a Lego job. However I try to steer a course between making life easy on the one hand and using and improving ones skills on the other hand. The laser profile saved a lot of time just doing a basic outline, I still spent a lot of time marking out and drilling all the holes. (It was actually a pleasant afternoon in the garden under the sun shade on a nice sunny day, set up the frames and my digital height gauge on a table, fed with the odd cuppa by my ever loving) Bill D |
HobbyNut | 05/11/2013 23:13:08 |
![]() 113 forum posts 93 photos | Posted by Stovepipe on 05/11/2013 21:42:41:
Since when did using the best technique (laser profiling) constitute cheating ? I can't pretend to know much about this topic, but using the best technique surely would probably save trouble further down the line. Dsnnis
I agree, I waterjet cut mine, holes and all!!!. I also made a "spider" to set them on so that they were aligned too! I would bet that if lasers, CNC and welding were as advanced as now, back in the late 1800's early 1900's, the rivet manufacturers and iron foundries would have gone out of business. Just my opinion of course. |
James Sutton | 08/11/2013 01:24:50 |
![]() 18 forum posts 7 photos | The guys at the track keep telling me that a little rattling makes it run smooth. I wouldn't worry about it. Also, use the resources you have available. Laser cutting is not cheating in my opinion. Keep up the good work. |
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