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Discussion Starter · #1 ·
I find that three Peco 00 gauge points on the layout work efficiently with regards to changing rail track routes, but as the powered part of the locomotive traverses over the point a distinct "thump" sound can be heard.
Can any rectification be carried out to eradicate this sound other than replacing the points in question? Points have been laid some fifteen months, with light usage.
 

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Discussion Starter · #3 ·
Peco points were purchased new, last year. Locomotives (diesel) are Bachmann DMU, Hornby, Heljan and Fleischmann are all in the two year bracket.
Heljan type (diesel) cross these points relatively quiet, Bachmann DMU 158 being the worst offender.
 

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Just trying to help here double00. Sound is such a subjective thing so perhaps you could clarify a little. Is this "thump" of a metallic nature, like a clang of two metal objects meeting, a loud click as when metal wheels go over a rail gap (love that noise), or a duller noise when metal meets non metal, perhaps a non metallic sound altogether.
 

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Sorry to add to the questions, but it might narrow things down a little . . .


To repeat Colombo, are the points Code 100 rail or finer?
Live frog or dead frog?
Solenoid or hand operated, or some other control?
Is the 'over-centre' spring doing its job? ie are the switchblades set firmly for the correct routing, without any slack or play?
Does it happen on both curved and straight routes?
Does it make any difference from which end of the points the loco approaches?
Are the points and other track pinned down?
Is the track truly flat?
Is there any underlay below the track and, if so, what material is it?
Lots of questions but the answers might help to track this down!
 

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Discussion Starter · #7 ·
I will try to answer the questions kindly generated by members of this Forum.

Setrack code 100 ST240-1 nickel silver.
Frog dead or live. - Live.
Solenoid or hand operated - Hornby motor Mk1 R8014.
Switch blade - If set by hand, blade can stick. Set by motor firm connection to rail.
Faults happens on - the straight. (not located on curve rails).
Direction affects - both ways. More when traversing to the left (clockwise).
Location of points - not pinned to layout board. Rails either side of point, stuck
down.
Track level - flat.
Underlay - none fitted through out layout.
Sound emitted by loco/coach. - Hollow clank rather than rhythmic clicking.
Movement of rolling stock crossing over points. - Slight move (both sides) and
slight shudder.
Rolling stock passes over blade. - last.
Fault found worse when using rolling stock made by - Bachmann 158 DMU.
 

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So you are using recently manufactured stock with code 100 points.

The stock you use will go better through code 75 points which have finer clearances between the check rails and the running rails. The distance between the backs of the flanges should be 14.2 mm to 14.5 mm.

Older Hornby and Lima stock needs code 100 points as the back to back is about 13.5 mm. They will struggle through or derail if you use them with code 75 points because the check rails are too tight.

If you look at the crossing Vee on your code 100 points you will see that there is a place beyond the apex of the vee where the wheel tread is unsupported. Older stock has deeper flanges and the edge of the flange is supported by the plastic base of the crossing Vee.

Modern stock has shallower flanges and therefore the wheel is not supported as it goes through code 100 points. As a result your 4 wheeled rolling stock and bogies will momentarily be supported on only 3 wheels. Some will rock as they go through code 100 points and you may hear a bump.

Code 75 points have a shorter unsupported length before the crossing Vee as the check rail clearances are tighter. Therefore there is much less tendency for the wheels to drop. The answer is to use code 75 points and track and re-wheel any rolling stock that has deep flanges. You should also adjust the back to back of any wheel sets that are set to less than 14.2 mm back to back.

You can use your code 100 track and points in the fiddle yard in future. Don't blame your supplier if you did not specify code 75 points to him. In effect he sold you "universal" points.

Colombo
 

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I had problems with short-wheelbase wagons, not locos, that didn't like a particular point and kept derailing, particularly at slow speed. I found a video camera (8mm Digital type) most useful in solving the problem. By videoing the area of the frog as a train went over at different speeds, downloading onto DVD and using the pause or slow play facilities of the DVD recorder/player, I was able to track down virtually the identical problem to double00's with one of my points.

But there was very little noise accompanying my problem, so I was unable to link double00's problem with mine until Columbo's comments above.

Hope this information may be of use to anyone else who has persistant problems with any area of track.

John Webb
 

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Discussion Starter · #10 ·
I was under the impression that code 75 track rail/points were sold by Peco under the brand name of "Slimline". Certainly, I checked the various packing material housing the points and track made by Peco - no code numbers are shown on the packaging. With this information in mind, I have no idea what code I am using.
Going back to my previous writing, The Bachmann 158 DMU powered coach certainly emits the noise in question when crossing the widest part of the "V" on each of my six points, while the unpowered coach crosses with a lesser level of noise. As stated prior, all other powered units cross the same points with no sound heard.
 

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Discussion Starter · #12 ·
Have the bogy wheels been checked? honest answer is a sheepish "No".
It would be appreciated, what type of gauge is required for this exercise? and the best method to alter the bogy wheels if found incorrect- wheels fitted in the Bachmann 158 DMU are the non-pointed type.
 

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Newer stock should be between 14.2 and 14.5 back to back. You have to be very careful when adjusting locos driving wheels, they are better left alone if possible.

I would use my trusty old vernier gauge to measure back to back.

Colombo
 

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Discussion Starter · #14 ·
Colombo - I am puzzled in what you say. "Adjusting loco driving wheels, they are better left alone, if possible", so why measure distance back to back, other than to learn your loco wheels are incorrectly set.
However, your assistance is always appreciated.
 

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He might be worried that you would bend something. I use an NMRA gauge. Don't you Brits have something similiar. If you find that they are not the proper width then bring them to a repair shop that has the proper tools/knowledge not to bend where no bend belongs. Check the train clubs and get yourself a gauge.



Flanges and points along the top, wheels on the left. Works every time. Every member of NMRA gets one of these. If the wheels don't fit in the nibs they're wrong and if the bottom of the gauge doesn't slide nicely around the track the track needs to be bent or tossed, end of story.

There are two hobby organizations that I put absolute faith in; one is NMRA and the other is APS.
 

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I am always a little worried about advising people to regauge loco driving wheels. There is a special tecnique for each type. I have had some success and some failures, and you can end up with loose driving wheels, loss of quartering, bent axle stubs and so on. I would not want to give advice that results in the ruin of someones loco. Neither would I offer to do it for them. It always has to be the decision of the owner whether or not to proceed.

On the other hand an experienced modeller may not see it as a problem.

Colombo
 
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