Why Would I Choose 00-SF ?

[martin_wynne]

Thanks for the post; in case you felt that a previous posting of mine was mis-placed I have removed said posting.

 

Hi Brian,

 

My only concern is not to post anything which may cause the RMweb mods to lock a topic. Knowing how trigger-happy they can be on this, you can't be too careful.

 

I have now replaced my previous post with a linked image under my control, so even if the topic does get locked I can still update or amend it.

 

regards,

 

Martin.

[hayfield]

May be its just best to ignore certain posts and just carry on as usual, but I must admit it has livened up the thread and given a few of us a laugh.

 

On the down side is the constant extremely detailed technical arguments, which may give some concern that 00-sf does not work. When there is a simple answer:-

 

Most modern wheel sets work, on the rare occasion either re-gauge with a back to back gauge (modellers should have one anyway) or replace with some new ones

[dasatcopthorne]

Now back to the title of the thread, please tell us why you would choose 00-sf

 

I've asked that question, but no reply, of course.

 

Not prepared to give his real name either!

 

Dave

[Junctionmad]

 

 

On the down side is the constant extremely detailed technical arguments, which may give some concern that 00-sf does not work.

yes, and bizarrely, repeatedly and aggressively made.  This suggests an " agenda" to  most people. Personally I dont see the point of their arguments, its either (a) 00-SF is unnecessary or (b) 00-SF is mis-representing  itself 

 

the answer from its adherents is " so f&*ing what", it works for me.   I cant then see why the argument is then pushed further.  00-SF is not a " standard " in the recognised sense. it a construction methodology that provides certain benefits to its adherents. 

[trisonic]

No one has to follow 00-SF. Thank God.

 

So ignore it... It’s only toys.

 

 

Best, Pete.

Edited September 7, 2015 by trisonic

[gordon s]

OK, we've talked about 00-SF for years and years and clearly there is a difference of opinion on it's merits. Those of us who are using 00-SF are very happy with our choice and will continue to use it. We have talked about our perceived advantages ad infinitum, so there is no need to go over that again.

 

Ravenser, you have equally spent years extolling the virtues of DOGA Fine and Intermediate telling us there is no need for 00-SF.

 

The one thing I have yet to see from you is any reason why anyone shouldn't use 00-SF.

 

Let's set aside the freedom of choice to go with either standard for a minute and please tell me why not to use 00-SF.

[Siberian Snooper]

I've asked that question, but no reply, of course.

 

Not prepared to give his real name either!

 

Dave

I did think about posting a reply, but I thought that one or two DOGA supporters may throw some more toys out of the pram.

[dasatcopthorne]

I did think about posting a reply, but I thought that one or two DOGA supporters may throw some more toys out of the pram.

 

Very interesting. S S.

 

Believe it or not, I'm a toy collector!

 

Dave.

[AndyID]

 

The above text is a linked image in case of topic-locking. If the above link doesn't work, or this topic is locked, go here: http://00-sf.org.uk/wiki/index.php?title=RMweb-1

 

regards,

 

Martin.

 

Thanks Martin.

 

I'd just add that if you do use two strips rather than a single piece it should be checked with the caliper from time-to-time in case the dimensions of the wood have changed slightly.

 

There was some discussion earlier about tapered gauges for measuring b2b. That should work as long as the wheels don't have any axial runout (wobble), but a lot of the wheels I've been looking at do have quite a bit of runout and that would produce misleading and inconsistent results.

 

Cheers!

Andy

[trustytrev]

Hello,

       I think plastic axle/wheels are likely to distort over time which could explain why the back to back tends to vary causing problems.

Metal wheels on metal axles seem to be truer than those in plastic and are unlikely to distort over time.

I choose 00-SF not because it is easy but because it suits the effect I want to acheive without lots of extra unnesasary effort altering wheels on RTR products. I can also build what I like with the help of Martin's Templot software to virtually any prototipical layout I want.

 

 

I'd just add that if you do use two strips rather than a single piece it should be checked with the caliper from time-to-time in case the dimensions of the wood have changed slightly.

It may be better to use veroboard.

 

trustytrev.

[AndyID]

I think plastic axle/wheels are likely to distort over time which could explain why the back to back tends to vary causing problems.

Metal wheels on metal axles seem to be truer than those in plastic and are unlikely to distort over time.

 

 

Hi Trev,

 

It could also be that some of the plastic ones were not much good in the first place. I have a lot of Peco nylon wheels (no longer produced?) which are really first class. Also, in my experience, they don't seem to pick up crud any worse than metal wheels. Of course they don't make a satisfying click when they go over a rail joint.

 

I finished the gauge. One side is 14.2 and the other is 14.3 mm. Now, if I had been planning ahead instead of machining random chunks of aluminium, I would have realized that I could get four gauges on one piece of metal. I suppose I actually did sort of, but for no particular reason the other two turned out at 9.5 mm which won't be particularly useful unless I decide to add some narrow gauge on my layout  

 

Cheers!

Andy

 

[AndyID]

Oh dear! It's getting more complicated.

 

 

The b2bs on this Hornby methanol tanker measure with a caliper at 14.16 and 14.17 mm. Not good! Time to do a bit of adjusting you might think, but not so fast. The tanker runs perfectly along the 14.3 mm b2b test gauge. No indication of the slightest bit of interference.

 

"It's obvious you've been consuming the contents of the tanker Andy."

 

Well, no. This is the reason:

 

 

That ring around the back of the wheel is a machined bevel that extends well beyond the wheel's tread. That makes it extremely difficult to accurately meausure the b2b with a caliper at the radius where it really matters.

 

In fact these wheels will have no difficulty negotiating 00-SF turnouts (or DOGAi turnouts come to that) without any adjustment, but it's not difficult to imagine how someone might think otherwise.

 

 

 

 

 

[Ramblin Rich]

That's a very 'interesting' (ie potentially irritating!) find Andy! A standard B2B gauge would also give the impression of being tight, leading to unnecessary adjustment - and presumably, some grief when running through pointwork due to the outside edges then being too wide. A very useful image - thanks!

[AndyID]

That's a very 'interesting' (ie potentially irritating!) find Andy! A standard B2B gauge would also give the impression of being tight, leading to unnecessary adjustment - and presumably, some grief when running through pointwork due to the outside edges then being too wide. A very useful image - thanks!

 

Hi Rich,

 

Yes, it would seem to indicate that it's quite important to use some sort of test gauge before doing anything else. In retrospect, I probably should have added 14.4 and 14.5 tests on the one I made. I don't think there is any need for for granularity finer than 0.1 mm (about 4 thou).

 

Do the magazines still publish the b2b dimensions of new models when they review them? I have not been paying attention, but if they still do, I'd be interested to know how they make the measurement. If they are inserting a caliper between the wheel backs they could be up a gum tree, leading us down the yellow brick road until we are up the creek.

 

Cheers!

Andy

[Grovenor]

i don't see where the problem is, you measure back to back between the flanges only, not any other part of the wheel, its just a matter of looking what you are doing.

Regards

[martin_wynne]

If what we are learning about the back of RTR wheels is typical, it seems that conventional back-to-back gauges should go in the bin.

 

Andy's style of rolling test plate is much more appropriate, but even there a 1mm slot may be too deep -- the RP25/110 flange depth is 0.025" (0.65mm).

 

Martin.

[martin_wynne]

i don't see where the problem is, you measure back to back between the flanges only, not any other part of the wheel, its just a matter of looking what you are doing.

 

Hi Keith,

 

Yes, but most folks don't measure back-to-back. They check it using the generally available back-to-back gauges -- typically a turned blank with a U-slot for the axle:

Martin.

Edited September 8, 2015 by martin_wynne
image link added

[AndyID]

i don't see where the problem is, you measure back to back between the flanges only, not any other part of the wheel, its just a matter of looking what you are doing.

Regards

 

Hi Keith,

 

It's not that simple. Unless you have calipers with some sort of insertion stops, with these wheels, you are going measure values that are all over the place. That's what alerted me to the problem in the first place. If you happen to have a set of Hornby wheels like these, I suggest you try it and see how you get on.

 

As Martin and Rich have pointed out, with these particular wheels at any rate, the type of b2b guages that have been around for years are not going to set the b2b at the intended value.

 

Cheers!

Andy

[AndyID]

If what we are learning about the back of RTR wheels is typical, it seems that conventional back-to-back gauges should go in the bin.

 

Andy's style of rolling test plate is much more appropriate, but even there a 1mm slot may be too deep -- the RP25/110 flange depth is 0.025" (0.65mm).

 

Martin.

 

Hi Martin,

 

Yes, the depth concerns me too. I machined them at 0.035", but there are many different flange heights.

 

The correct method would be to support the wheels on their treads rather than on their flanges. I actually made the overall width of the gauge 16.2 mm with the idea that I could add a flat plate to act as a rail.

 

Another idea might be to just machine or file a plate to the correct width and mount it on a short length of track with shims to bring it up to the correct height. If the track had copperclad sleepers, the plate could be made to match the rail height.

 

Cheers!

Andy

[hayfield]

Hi Keith,

 

Yes, but most folks don't measure back-to-back. They check it using the generally available back-to-back gauges -- typically a turned blank with a U-slot for the axle:

Martin.

 

 

Would the type made from a length of angle iron be better ?

[AndyID]

Would the type made from a length of angle iron be better ?

 

Hi John,

 

If I'm thinking of the same thing that you are, they would still have the same problem if the backs of the wheels are not flat all the way to the tread diameter. This might not be such an easy problem to resolve.

 

Cheers!

Andy

[Grovenor]

Yes, but most folks don't measure back-to-back. They check it using the generally available back-to-back gauges -- typically a turned blank with a U-slot for the axle:

The question above related to measuring with calipers, but its just the same using a gauge.

It's not that simple. Unless you have calipers with some sort of insertion stops

It is that simple, a matter of looking what you are doing and measuring or gauging on the flanges. I have gauged hundreds of wheelsets including quite a lot with the sort of step you illustrate. Nothing says you should push the axle right into the slot in the gauge, or into the corner if its a L shape gauge. You look at the backs of the wheels and only insert the gauge to the depth of the flange in such cases. Its quite common where metal tyres are on plastic centres for the plastic to be proud on the back.

Regards

[Arthur]

It is simple Keith so long as you know, and appreciate the implication, that the BtoB at the flanges might be different to the BtoB at the axles. Most would use the gauge 'as intended' without realising the problem.

 

It's now something I shall be more aware of thanks to Andy's efforts.

Edited September 9, 2015 by Arthur

[number6]

I would love one of these gauges - very useful - but I have a large 00-SF layout and I have run a huge variety of wheels through the pointwork without one so far. 

 

In many cases I couldn't tell you what the back to back is in mm - I have merely tested the wheel on the track and tweaked the gauge until it runs smoothly. I have various gauges but they are often only a starting point. An existing wheel which runs is often my preferred gauge - hold them up and compare the back of the flanges. I've never had to re-gauage a Romfords/Markits wheel/axle but I have had to pull out a few early China Hornby loco wheels. Never any Bachmann locos except those wheels in the terrible new LMS bogies with plastic centres. They went in the bin. 

 

The wheels which require the most care are Gibson coach and wagon wheels because of their thin tread and often have to be very finely judged. This I do with a tweak of the wheel press/puller or just my fingers and then testing through pointwork. I then mark the bottom of the vehicle as gauged and off it goes. With respect all the time spent with calipers and gauges could be better spent re-gauging at a speed so it becomes like shelling peas!
 

With respect - like a lot of aspects of this hobby there can be a bit over overthinking going on here. Checking back to backs and adjusting is very easy to do- takes no time at all and is probably something people running pure PECO could spend some time doing because it pays dividends in good running. I have PECO in the hidden yards and any adjustments to run through 00SF have had no detrimental effect.

[Izzy]

Although I haven't used OO gauge since the early 1970's I have followed the threads on OO sf with interest, not realising or appreciating until recently when playing about with some 4mm plastic kits for a little project just what a minefield OO wheels and their standards still are today. The kits all came from the same maker, yet of the 5 only two included wheelsets of a similar standard.

 

Taking this into consideration, if I may make a few comments on the issue currently faced, correct b-t-b setting for the OO sf standard - and could equally apply to other track standards where variable wheel profiles are used together - using a standard/conventional b-t-b setting gauge is of little help or benefit. Such a gauge, whatever the form, roller type, L shaped, is only of real benefit for setting wheels with an identical and consistent b-t-b when the wheels are of a common standard/profile.

 

Where you are trying to set wheels of varying profiles/widths to run on track to a particular set standard, and when wheel run-out and tapered rear faces need to be allowed for, then a go/no-go gauge of the type already illustrated is really the only way of setting a usable running b-t-b measurement as far as I can see and will vary for each different profile.

 

This type eliminates the flange depth as an issue because the wheel runs on the tread so the rear face will contact the checkrail at a consistent height, that of the tread. And run-out can be seen/felt and judged as to whether it is an issue. Low levels of run-out are often present in wheels, but below certain figures don't appear 'wobbly' while above suddenly do. Even where this exists and can be easily seen it doesn't always present a problem, if an equal level of run-out is matched on the opposing wheel i.e. diametrically opposite on the circumference. The whole wheelset might be quite wobbly but the b-t-b may remain constant so they run through check areas without issue. However, twist the wheels so they don't match, and not only will the b-t-b vary over the wheel circumference but there will be tight spots when running through checks. This is where twisting the wheels on their axles - where possible - can turn wheelsets from no good to acceptable as far as negotiating track is concerned.

 

Hope this is of use, and I'm not stating the obvious.

 

Izzy