Keyboard Shortcuts
Likes
Search
Back to back gauge
开云体育Roy/All,I appreciate your concerns that the standards relate to the wheels you originally produced, so I thought it would be useful to measure my locos and rolling stock which use other types wheels. Results are: Wagons - mainly Alan Gibson OO wheels re-gauged (I'm assuming these are RP25) - 12.4mm Manning Wardle 2-6-2 -? Alan Gibson wheels intended for the 7mm L&B kit - 12.4mm Baldwin 4-6-0 - very old Alan Gibson wheels intended for OO/EM - 12.4mm K1 Garratt - coarse Romford/Markits wheels on 14mm axles re-profiled with Scale7 tool - 12.3mm From the above I would assert that the modern fine RP25 standard wheels set to 12.4mm will work just fine. Interesting the B to B part of my old RCL standards gauge (which O confess I rarely use) seems to measure at 12.6mm. I don't believe my 15 year old (but carefully looked after) Mitutoyo vernier caliper is at fault. Regards John |
|
Roy Link
开云体育John,This is very useful information, particularly as, to my knowledge you have more practical experience with regards ‘mainline’ O14 than myself - or anyone else I can think of. The RCL standards were developed solely for my O14 range of small ‘industrials’ - which gained their reliability only from keeping everything within tight constraints. Both locos and stock had similar wheelbases and overall lengths - enabling sharp curves to be easily negotiated in both directions, desire their light weight. Your locos and stock are much bigger and heavier, so they will tend to roll through slight inconsistencies regards flangeways and gauge. To the best of my knowledge, while Alan Gibson and MayGib were producing - all the ‘OO’ wheels were close or identical to 1950 BRMSB EM profile and classed as OO/EM fine scale. Both firms made the same wheels with a tyre for P4, which was much finer. Note that the BRMSB also had standards for ‘EEM’ - a fine scale version which later became the ‘EM’ standard, the plain ‘EM’ being deleted in favour. I don’t believe Alan ever used an NMRA RP25 profile - though I cannot vouch for the current firm producing under his name. The ‘RP' (NMRA) by the way, stands for ‘recommended practise’ and their are separate codes for the actual profiles. The one we would be interested in is code 110. See: You can get 110 wheels of varying diameters from NWSL in the US. Experiments made while I still had ‘NG Sand & Gravel’ in my possession showed that, with a back to back reduced to 12.45mm, Sn3 wheel sets would track well through type 2 turnouts as defined in the old Product Handbook. The advantage of the 110 profile is a greater width of tread and flange - the latter being well rounded. The BRMSB EM wheel by comparison, was slightly over width for Festiniog wagons, but under width for locomotives - as per the profiles shown in Vignes Atlas. Quite why you have one of my old gauges that measure 14.60mm on the back to back part is baffling. I know I did alter the tongue on the gauge progressively upward from 12.40 to 12.50 - as I found on type 1 and 2 semi-portable turnouts the higher figure proved more reliable. Possibly I did a batch with the wrong cutter (too small) - so the gauge ended up oversize - but this would mean the railhead slots would be on the tight side, to say the least. As regards frame widths for O14, these will vary depending on the type of axle box chosen. Sprung or equalised boxes need a bit of play to work well, plus the tolerance required in the relationship twixt box and axle, required for free articulation. On 24 Jan 2015, at 12:17, John Clutterbuck jclutterbuck2001@... [O14] <O14@...> wrote:
|
开云体育I am pleased to say that the price on the gauge will now be ?7 thanks to the quantity of the order.
It will be 4 weeks or so before these are produced.
James Hockley?
Sent from my Samsung Galaxy S5 - powered by Three
-------- Original message --------
From: "John Clutterbuck jclutterbuck2001@... [O14]" Date:24/01/2015 12:17 (GMT+00:00) To: O14@... Cc: Subject: Re: [O14] Back to back gauge ?
Roy/All, |
|
toggle quoted message
Show quoted text
On 25 Jan 2015, at 18:27, James Hockley jameshockley_38@... [O14] <O14@...> wrote:
|
开云体育Hi Marc, ? Sorry to chase but are you still after the 014 back to gauge? ? They have arrived at last. ? Either way if you could let me know. ? They are ?7 plus postage of 80p. ? Paypal gift would be great – jameshockley_38@... ? Kind regards ? James Hockley ? From: O14@... [mailto:O14@...]
Sent: 25 January 2015 21:58 To: O14@... Subject: Re: [O14] Back to back gauge ? ? That's great Marc
|
David Hughes