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Post by ron on Mar 12, 2007 20:48:45 GMT
Hi Everybody I've searched the archives and haven't really come up with a definitive answer, can someone tell me the easiest way of quartering wheels [Loctiting] I've set a pair of my Simplex wheels between centres on the lathe but I can't really get a consistent result with bits of packing off the bed or the cross slide. Any hints and tips welcome. Ron
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Ansty
Involved Member
Posts: 59
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Post by Ansty on Mar 12, 2007 21:27:51 GMT
Ron
When I quartered my wheels (3 1/2G) I made a jig that even if a bit out of 90 degrees the axle sets matched. I'm afraid that I cannot now remember where I got the idea from. Basically it was three pieces of bms in a U form with the axles supported by coned screws and the sides cut to provide the 90 degrees for the pins.
If I remember where I saw this I will let you know.
Sorry I cannot be more specific.
Brian
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Post by chameleonrob on Mar 12, 2007 21:38:47 GMT
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hat
Active Member
Posts: 48
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Post by hat on Mar 13, 2007 9:30:31 GMT
There is a detailed description of the jig in Martin Evans book " Rob Roy and William "page 134 - basically two plates with the ability to set the wheel accurately between the plates with holes for the pins at 90degrees apart - therefore when assembling one pin goes into one hole and the other at 90degrees - If the plates are drilled together as a perfect match its foolproof - and as already said, if its 91 degrees no matter so long as they all match. If my description is unclear I will attempt to scan the page and post it???
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Post by ron on Mar 13, 2007 10:27:54 GMT
Hi Hat I would be obliged if you could scan and post it. Ron
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hat
Active Member
Posts: 48
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Post by hat on Mar 13, 2007 12:07:21 GMT
Ron I am having a problem posting the page that I have scanned - I thing I will have to copy type it! So could be in the morning
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Post by ron on Mar 13, 2007 17:05:33 GMT
What about making the coupling rods and using them to quarter the wheels actually on the loco? that might also have the advantage of reducing the risk of them binding once they are fitted. Anything I've read seems to suggest that it isn't critical that the quartering is exactly 90 degs it's the consistency that matters. Ron
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hat
Active Member
Posts: 48
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Post by hat on Mar 13, 2007 17:24:43 GMT
So quoted from the Martin Evans book "To make a good job, two steel plates about 41/2 inches wide and 1/4 thick and any length over 6 inches will be required. In the extreme corners of these plates !/4 inch holes are drilled and reamed, done together so that they match. Then in the center of each plate a further 1/4 reamed hole is provided and at exactly 90 degrees to one another two holes are drilled to take the crank-pins, these holes being the distance from the center hole equal to the throw of the driving wheels. Next we require four pillars turned from steel 1/2 diameter , each end of which is turned down exactly to 1/4 inch for a length of 3/16, followed by a further5/16or so which is threaded 1/4 BSF.The length of these stretches should be such that the wheels on their axles can be placed in between the two plates with about 1/8 inch end clearance. Next two centers of 1/4 silver steel with one end pointed to seat in the axles The plates are prepared with one end bolted up. The driving pins are located at 90degrees to each other and the whole thing is bolted up ------" He says use locktite 601 and leave them overnight - he also suggests pinning the wheels by drilling and threading and inserting a 4 BA bolt placed equal distance in the axle and the wheel - bolt up tight and crop it off
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John Lee
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Post by John Lee on Mar 13, 2007 19:05:06 GMT
What about making the coupling rods and using them to quarter the wheels actually on the loco? that might also have the advantage of reducing the risk of them binding once they are fitted. Anything I've read seems to suggest that it isn't critical that the quartering is exactly 90 degs it's the consistency that matters. Ron Hmm, think of the process Ron, I can't envisage this. You put the wheels on, and add the coupling rods, and then how do you loctite/pin/keyway your wheels? Loctite is out, the other methods are freehand and only a pin is practical. I think..... I am often wrong Regards, John
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Post by gilesengineer on Mar 13, 2007 19:22:12 GMT
I have quartered (the second pair of) wheels using the rods, and rolling the chassis back and forth to ensure free movement - and it actually worked really well! (this was in 10 1/4"). As already stated, you had to quarter and fix the driving pair first, together with the third wheel (if it is four-coupled). The wheels were bored to the appropriate fit for the loctite, put on to the axles, rods fitted, and the rotation of the one wheel adjusted until I was happy. After it set, I then drilled and pinned with silver steel, and they certainly never moved, and there has never been any binding. One might very well argue that this (rather crude empirical) technique is better suited to larger sizes - and that good engineers would be best doing it by use of jigs etc. but it does work if you need to do it this way..... ;D
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Post by ron on Mar 13, 2007 20:40:16 GMT
I quite like this idea the more I think of it, I'm trying to build a loco, not spend my time making jigs and fixtures I probably won't use again. M Evans method will work well [thanks hat] but he seems to come from a generation of model engineers that picks the most laborious way of doing anything. I'll quarter the drivers using a setsquare and scribing block on a surface plate, leave overnight to set, the second and fifth wheel are already Loctited so I'll do the leading pair as per Gilesengineer method, leave overnight to set then do the trailing pair, if it doesn't work it's easily enough undone with a bit of heat. Do I need to pin them [if it works ], I was just going to use Loctite?? I'll need to make the conrods first though ;D Ron
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Post by gilesengineer on Mar 13, 2007 21:17:33 GMT
Ron
It will certainly work - the only thing I would say is that it is best to make sure the flanges of the wheels are actually the same diameter (assuming you are rolling the chassis on the flanges - better than using track on the tapered treads). When you loctite the final wheels, let them rest with the rods up or down to get maximum comfort of accuracy. Certainly my locos (with wheels disconnected from cylinders) will roll to rest rods down, just under the weight of the rods, demonstating the free-wheeling. All the best
Giles
If you've not yet made the rods, or question your ability to get them completely accurate, you can make up temporary ones, with simple bosses machined to fit the crank-pins, and tack welded or bolted to form the correct length (I'm not explaining this well - it's been a long day...) and use that as a drilling jig to make your real rods.
My profuse apologies if I'm teaching my Grandmother to suck eggs -
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John Lee
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Post by John Lee on Mar 14, 2007 3:43:30 GMT
The wheels were bored to the appropriate fit for the loctite, put on to the axles, rods fitted, and the rotation of the one wheel adjusted until I was happy. After it set...... Giles, So, maybe I am being a bit thick here. You put your loctite on the axles, add your wheels. then add both sets of rods and adjust until happy? The loctite I use would long ago have gone off, it starts to grab in 10 seconds or so when it is anaerobic, i.e. wheel on axle (I must nip off and take a look as to which one). Even with the slow setting stuff you have not got long. And then you pin it freehand or somehow manouvre a set of completed frames, wheels and rods under a mill or drill to put the pin in square. In 10 1/4 gauge the mind boggles ;D. Regards, John
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Post by gilesengineer on Mar 14, 2007 8:53:34 GMT
Hi John,
In the case of a four-coupled loco, you would fit three of the wheels normally, and only fit the fourth in this way. I'm ashamed to say that I can't remember exactly which loctite I use - I think it's a shaft lock, which sets in about 15 minutes.
Having got your chassis assembled on a (big) bench or dolly - as a three legger, with coupling rod fitted on one side, you then apply the loctite, ease the final wheel on to the axle (crank down), and fit the coupling rod (probably tapping the wheel round to get the rotation right), and wheel it up and down to check for any tight spots, and then let the loctite go off. It's easier to do than to explain....! You're right though, it really wouildn't work so well with an adhesive that sets so quickly!
Regards
Giles
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Post by gilesengineer on Mar 14, 2007 8:58:46 GMT
P.S. I pin as 'belt and braces' after it's all done and dried. A 10 1/4" frame set is no problem to handle with an engine crane (indeed I'm less likely to put my back out than some of the 5" chaps..!) - but you don't want to trap your fingers anywhere....
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Post by ron on Mar 14, 2007 10:29:55 GMT
I'll post how I get on, one way or other, I've got lazer cut conrod blanks with the centres marked so they should be accurate and I've checked the wheel centres and they are accurate side to side. John, as far as I can see, by using this method there is only one wheel being Loctited at any given time so as long as I don't use a superfast Loctite there should be time enough. As I posted before it's easily dismantled if it doesn't work and it will save a lot of jig making if it does. I'm off to York on holiday next week ;D so it probably won't happen till after that. Ron
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Post by Nexuas on Mar 14, 2007 12:25:06 GMT
Having seen first hand what happens when the loctite fails, and a wheel moves on an axel. (5" Don young Hunslet -> 2 foot drop at 7-8MPH NOT PRETTY) I would strongly recomend some form of Mechanical fixing to help keep the wheel in place!!!
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Post by ron on Mar 14, 2007 17:34:37 GMT
Having seen first hand what happens when the loctite fails, and a wheel moves on an axel. (5" Don young Hunslet -> 2 foot drop at 7-8MPH NOT PRETTY) I would strongly recomend some form of Mechanical fixing to help keep the wheel in place!!! OK Thanks Ron
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John Lee
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Post by John Lee on Mar 14, 2007 19:18:57 GMT
I'll post how I get on, one way or other, I've got lazer cut conrod blanks with the centres marked so they should be accurate and I've checked the wheel centres and they are accurate side to side. John, as far as I can see, by using this method there is only one wheel being Loctited at any given time so as long as I don't use a superfast Loctite there should be time enough. As I posted before it's easily dismantled if it doesn't work and it will save a lot of jig making if it does. I'm off to York on holiday next week ;D so it probably won't happen till after that. Ron Ok Ron, You must be nippier than me with the Loctite. If this method works do tell far and wide as it will save a lot of messing about. ME had time as he had multiple locos planned ahead. I am a fan of jigs, but only if I can use it again and it does not take me long. Have fun on your holidays, PM if you are bringing a loco and want a run around with it in York. Regards, John
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Post by ron on Mar 14, 2007 20:16:46 GMT
Hi John Unfortunately I haven't got a loco to bring, hence the enthusiasm to get on with Simplex, don't know if the wife would be over the moon if I brought one on holiday anyway. Ron
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