Model Railway Forum banner
1 - 20 of 20 Posts

·
Premium Member
Joined
·
743 Posts
Discussion Starter · #1 ·
When I completed the track laying on my fiddle yard, I noticed that two of the five locos I was using for testing where shorting my ECoS when travelling over points. Great I thought a problem with the wiring. Thankfully, the wiring appears to be ok. That leaves me to suspect the back to back wheel measurements as being a problem as the other three locos have no problems.

I then bought the C&L back to back gauge for 00:



However, I am not sure how best to use this gauge. I believe the measurement between the wheel backs should be 14mm, is this correct?

Also, is there an easy way to adjust this on locos or does it involve a complete dismantle to prise the wheels further apart?

Sadly I suspect this will be a problem with quite a few of my locos and I guess is an unfortunate side effect of DCC as it comes with the required better sensitivity of boosters that forces you to use best operating practises!

Rob
 

·
Just another modeller
Joined
·
9,983 Posts
QUOTE (80class @ 30 Mar 2008, 20:38) <{POST_SNAPBACK}>When I completed the track laying on my fiddle yard, I noticed that two of the five locos I was using for testing where shorting my ECoS when travelling over points. Great I thought a problem with the wiring. Thankfully, the wiring appears to be ok. That leaves me to suspect the back to back wheel measurements as being a problem as the other three locos have no problems.

I then bought the C&L back to back gauge for 00:

However, I am not sure how best to use this gauge. I believe the measurement between the wheel backs should be 14mm, is this correct?

Also, is there an easy way to adjust this on locos or does it involve a complete dismantle to prise the wheels further apart?

Sadly I suspect this will be a problem with quite a few of my locos and I guess is an unfortunate side effect of DCC as it comes with the required better sensitivity of boosters that forces you to use best operating practises!

Rob

Hi Rob

No, you cannot fix ONE back to back as some brands of wheels are thicker in flange than others, and this affects it.

NMRA standard is 14.5 which is OK for the last say ten years of production stock and my personal opinion is that the best performance with current H & B loco's is 14.75.

You should also consider adding 10~15 thou of styrene to the inside of the Peco chackrails so they actually check - this will stop the shorts too.

I am NEARLY finished development of a wheel puller that will allow adjustment without stressing the wheel or misaligning it (MOST existing pullers are bad as they don't support the wheel boss properly)

However - No matter what (1) you WILL have to remove the wheels to adjust.... (2) it will be worth doing - especially if you take them out to 14.75! The loco's will run better, pickup power better, track pointwork and enter curves better and seem smoother and surer on the track without the huge slop thats built into them ex factory!

Richard

PS - I make a gauge for 14.75 :). Email me off list if interested.
 

·
Premium Member
Joined
·
743 Posts
Discussion Starter · #3 ·
Thanks for clearing that up Richard, its an area that for whatever reason has never been that clear in my mind!

Rob
 

·
Premium Member
Joined
·
4,854 Posts
Hi Richard,

I have the same question relating to N Gauge. I don't know if I have a problem yet but might as well get my locos checked out now. i.e. What is the best b 2 b and do you do the necessary kit?

Regards,

Expat.
 

·
Just another modeller
Joined
·
9,983 Posts
QUOTE (Expat @ 30 Mar 2008, 22:44) <{POST_SNAPBACK}>Hi Richard,

I have the same question relating to N Gauge. I don't know if I have a problem yet but might as well get my locos checked out now. i.e. What is the best b 2 b and do you do the necessary kit?

Regards,

Expat.

Sorrry Trevor, but here I have to say "I don't know" really - I havent followed the evolution of N scale wheel profiles closely enough to give advice confidently.

Apart from saying that the same sort of advice will apply.

I'd take a look at the NMRA standards + any UK based N scale association - its also possible that the 2mm scale association (which does some stunning stuff, has an excellent reputation and very good website) may have both standard and 2mm standards available on their site.

As to the gauges - I don't right now but I can have them made if a proper defined size becomes clear - quite quickly!

Richard
 

·
Registered
Joined
·
2,202 Posts
check out the NMRA B2B standards for N?

regarding the shimming of check rails....this is an old trick, it appears, being re-juvenated...used in the past to improve 'stock- tracking' through old-style Peco points.......I first used it to 'cure' tracking problems on old points when using NMRA standard wheelsets.

also have used milliput/ auto filler to block out the crossing [frog] area, and to 're-cut' grooes for the wheelsets..to eliminate 'drop' at the crossing.....and shimming of the point rail/check rail at the crossing, narrowing the gap to enable a wheelset to be 'supported' on its travels through the crossing area, on its tread.

oh what tricks we all got up to?

needless to say...[regarding shimming the check rail]...... if mr Peco et al had really got their act together,and properly copied prototype practice....then the check rail would in fact play zero part in the guiding of the wheel flange to the correct side of the crossing vee......sadly, like having electric motors in boilers, we modellers have to stray ever so far from the real thing...
 

·
Just another modeller
Joined
·
9,983 Posts
QUOTE (alastairq @ 30 Mar 2008, 23:23) <{POST_SNAPBACK}>regarding the shimming of check rails....this is an old trick, it appears, being re-juvenated...used in the past to improve 'stock- tracking' through old-style Peco points.......

*** Ouch -hit my hot button


Yes Alistair, right on the money....and how sad it is that we STILL have to recommend this - they've had 25 years to stop Ba**sing it up for every modeller who uses their rubbish but they persist in making it wrong!

Actually what I'd rather say is "make your own, its easier than you think.... and you can make half a dozen properly for the same cost as one manky Peco effort!

Richard
 

·
Registered
Joined
·
536 Posts
HI
The Double O Association in the UK for the standard OO (Not finescale) B2B recommendation is 14.4mm +/- 0.05mm Here's a link to their standards page Double O Standards for Universal B 2 B

When Richard has finished his wheel puller can we have some more details including costs etc. Richard can you place something in the foirum when your ready please?
 

·
Just another modeller
Joined
·
9,983 Posts
QUOTE (Brian @ 30 Mar 2008, 23:41) <{POST_SNAPBACK}>HI
The Double O Association in the UK for the standard OO (Not finescale) B2B recommendation is 14.4mm +/- 0.05mm Here's a link to their standards page Double O Standards for Universal B 2 B

When Richard has finished his wheel puller can we have some more details including costs etc. Richard can you place something in the foirum when your ready please?

***Hi Brian

The DOGA standard was created a long time ago, and wheels have become finer since then.... it is way overdue for refreshing. 14.4 is frankly far too narrow for current wheelsets! NMRA = 14.5 - still Only just OK... do try slightly wider, it will surprise you

Richard
 

·
Just another modeller
Joined
·
9,983 Posts
QUOTE (Sol @ 31 Mar 2008, 11:08) <{POST_SNAPBACK}>Richard, DOGA now have 14.8mm for Finescale wheels

http://www.doubleogauge.com/standards/finescalewheels.htm

but I do agree that 14.5 would be better for Universal.

I modified that gauge from you at 14.75 back to around 14.6 - 14.65 & all is good.

***Why? if the trackwork is to DOGA as you build it, 14.75~14.8 would be perfect.

Richard
 

·
Premium Member
Joined
·
1,303 Posts
Richard, I have no problems with trackwork being to DOGA finescale but getting loco wheels out to 14.75 - 14.8 - I had great FUN with Hornby M7 wheels to match the gauge - collectors gave me problems.

I also have a couple of kit built locos made to run on Peco code 100 which I managed with difficulty to get them out to NMRA 14.5 & not sure on how much more I could move them out.
I also have just looked at a K's kit of a 44xx class 2-6-2 to build & the driving wheels are just 14.5 & the pony truck wheels well under.

I have also used Gibson wagon wheels & I must have had a couple under 14.5 coz they were a tight fit on NMRA gauge & when I twisted them out a bees' whisker, they came loose & even the rim's came off.

So I use your modifed B2B gauge which closely matches the NMRA coupled with the C&L type track gauges & all runs well - it is a matter of making sure hand made points are bang on - things do run better than thru Peco 75.
Before I started on Code 83 rail, I used 75 & the NMRA gauge used for wheels & track & in most cases RTR was not too bad - some Hornby wagon wheels were a bit tight for NMRA.
 

·
Registered
Joined
·
1,312 Posts
Take a look at Iain Rice's "An Approach to Finescale Track Building" for an informative and entertaining foray into the mysteries of wheel and track standards. By the way, I think one problem is that while the DOGA has published a standard the major players aren't required to abide by it (unlike NMRA). Getting the B2B right on rolling stock will make a huge difference to reliability, put a dab of superglue behind the wheel once set - I've found that the gauge can go off over time if you don't.
 

·
Registered
Joined
·
352 Posts
Found this thread very intresting, i use code 100 peco track work, and have four double slips sited one behind the other, some of my locos, especially my bachman jinty, will not travel over this section of track work at slow speed with out stalling, what seems to happen is that the front r/h wheel and the rear left hand wheel hit the frogs at the same time, and the loco effectivly tips into the frog, if you touch the loco it rocks back and forth, now im just wondering if this shimming of the frog and maybe the check rail will help ease this annoying problem?
 

·
In depth idiot
Joined
·
7,673 Posts
QUOTE (Thunder @ 9 May 2008, 11:33) <{POST_SNAPBACK}>.. especially my bachman jinty, will not travel over this section of track work at slow speed with out stalling, ..
Before working on the track, check that all the pick up collectors bear properly on the wheelbacks. It's a rare RTR loco that has the pick ups as well set as they can be. If so inclined take off the keeper plate. You will see that the centre axle is on a sprung plunger; a useful feature, except that the keeper plate holds the axle rigid. If you make two semi-circular rebates in the keeper plate sides under the axle position, and a broader rectangular cut out under the plunger the axle will be free to travel downwards. Take a half millimetre off the top surface of the plunger if there is no upward travel as supplied. That should mean 5 out of 6 wheels available for current collection at all times. Many Bachmann 'blue riband' steam models have a sprung driven axle, and without exception to date all my examples have been supplied with the axle constrained to a near fixed position.
 

·
Registered
Joined
·
763 Posts
I think you'll find that the NMRA back to back for RP25/110 wheels is 14.4mm , and therefore matches the DOGA Intermediate standard.

The finer wheels Richard is thinking about would be to RP25/88 and are a different matter . The nearest equivalent would be EM profile wheels (eg Gibsons) , which is what is defined by the DOGA Finescale standard, and that has a Back to Back value of 14.8mm

The DOGA Commercial/Intermediate standards have a revision date of 2004 , which is not "a long time ago" , and by definition a track standard and a wheel standard are two halves of a single whole . If you want to use wheels that don't matchwheel standard A, then it is not surprising if they don't then fit Track Standard A perfectly..

14.5mm has nothing to do with either DOGA or the NMRA , bvut is the old BRMSB figure , and I'd certainly not want to puish current RTR wheels out to 14.7mm or 14.8mm or anything between. That is simply going to ensure the check rails completely fail to operate
 

·
Registered
Joined
·
352 Posts
QUOTE (34C @ 9 May 2008, 11:59) <{POST_SNAPBACK}>Before working on the track, check that all the pick up collectors bear properly on the wheelbacks. It's a rare RTR loco that has the pick ups as well set as they can be. If so inclined take off the keeper plate. You will see that the centre axle is on a sprung plunger; a useful feature, except that the keeper plate holds the axle rigid. If you make two semi-circular rebates in the keeper plate sides under the axle position, and a broader rectangular cut out under the plunger the axle will be free to travel downwards. Take a half millimetre off the top surface of the plunger if there is no upward travel as supplied. That should mean 5 out of 6 wheels available for current collection at all times. Many Bachmann 'blue riband' steam models have a sprung driven axle, and without exception to date all my examples have been supplied with the axle constrained to a near fixed position.

Many thanks for that information 34C, will check to see if thats the case and try to adjust acordingly,
 

·
Just another modeller
Joined
·
9,983 Posts
QUOTE (Ravenser @ 9 May 2008, 20:03) <{POST_SNAPBACK}>I think you'll find that the NMRA back to back for RP25/110 wheels is 14.4mm , and therefore matches the DOGA Intermediate standard.

The finer wheels Richard is thinking about would be to RP25/88 and are a different matter . The nearest equivalent would be EM profile wheels (eg Gibsons) , which is what is defined by the DOGA Finescale standard, and that has a Back to Back value of 14.8mm

The DOGA Commercial/Intermediate standards have a revision date of 2004 , which is not "a long time ago" , and by definition a track standard and a wheel standard are two halves of a single whole . If you want to use wheels that don't matchwheel standard A, then it is not surprising if they don't then fit Track Standard A perfectly..

14.5mm has nothing to do with either DOGA or the NMRA , bvut is the old BRMSB figure , and I'd certainly not want to puish current RTR wheels out to 14.7mm or 14.8mm or anything between. That is simply going to ensure the check rails completely fail to operate

***Actually Ravenser I'm actively using 14.75~14.85 depending on wheel profile - yes, including gibson, Steam Era models and Markits PLUS current RTR and having superb running through all forms of turnout - My current layout has more than 100 hand built examples and I have also done the same as an experiment with Peco code 75 and current RTR wheels - setting them to never less than 14.75 after packing the check rails with appx 15 thou of styrene....which is what Peco needs for best performance anyway as their check rails are simply useless as "ex factory"

The result is incontrovertably a 100% success...

The penalty if there is one is that I do have to adjust BTB on every wheel set - but then I've always done that anyway as its critical to good running and the Mfrs can't ever be trusted to get it consistently right. Its no harder to adjust to a slightly wider BTB than a narrower one anyway.

As to NMRA being 14.4.... With the current wheels for most US Mfrs actually now consistently somewhat finer than RP-25 and often trending towards the RP25/88 standard (led by market forces demand) the NMRA 14.4 is now looking very tired and far too close together.

I'm not suggesting its for everyone but the higher running reliability and clearly visible improvement in running even on plain track is to me well worth the effort, and adjusting back to backs to optimise running is just good housekeeping.

Richard
 

·
Registered
Joined
·
352 Posts
have spent the afternoon carrying out some very minor surgery on my Bachman jinty, in accordance with the information given by 34C, and after suffering rough slow running over my double slip points, im now happy to report all is well, what a difference an hours work has made to this locomotive, its a pleasure to see it trundle over a whole section of point work smoothly, something its never done since new, a big thanks to 34C
 
1 - 20 of 20 Posts
Top