peco points

I have a bachmann ivatt 4mt and a small bachmann tank engine the tank engine runs through the peco 2nd radius points with no trouble but the ivatt sticks in the middle, both the points and the engines are new, can anyone explain why.

Jim

Reply to
jimpick67
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I find that several of my Bachmanns are prone to that - when I can see the problem , it is usually that the centre coupled wheel rides up on the floor of the frog guide thus causing the whole side to rise and remove power from the loco. My Hornby 51XX's do the same thing. I think that some of the set-track radii are really too sharp for 6 coupled locos as all my problems are with small radius streamline points. The older points are more forgiving (I have at least 3 versions of Peco Points in use).

Reply to
Peter Abraham

Dont think so, 2nd radius should be fine, more likely if centre wheels rising then check the back to back - more frequently a problem with Hornby than Bachmann. if centre wheels not rising then check that the pickups are actually touching the wheels. Make sure that all pickups are collecting power. This is more often Bachmanns problem.

Cheers, Simon

Reply to
simon

Simon, could, of course be correct BUT: I have been pretty meticulous in trying to determine causes for this problem - it being often a particular model with a particular point and dual directional. most of my 6 coupled locos loathe most of the curved points whilst running astern. My Bachmann panniers are all different in under-side arrangement but need careful passage over small radii track and points. The Bachmann 45XX can trip over its own ponie trucks almost anywhere. I use a universal 14.5mm b-b setting (where it can be set) whereas the minimum check rail value is a fairly consistent 14.1mm. Most Hornby arrives chez nous at 15.1mm. It is significant that my kit built locos loathe the same areas. ALL of the affected stock lack lateral movement on the centre axles. Just consider how the 6 wheel bogies perform - they have essentially a fully floating centre axle. I long concluded that there can be no solution because insufficient chassis space is available for lateral movement of the centre axle (s) or vertical movement (gravity only - no springing) with elongated axle slots as provided by the power bogies of the Hornby X941 type.

Of my collection of very diverse locos the most consistent and steady runners are (after the impeccable Athearn originals and conversions) the Bachmann, both UK Outline and US outline. I do have the equipment to verify that pick-ups are functioning properly and my commonest failures are always Hornby and this failure is almost always attributable to arced up wheel rims and tyres.

Finally, it is quite common to find peco points which are not flat . A warp of 1mm is quite common and this too can cause problems - it must be remembered that even the flatest of objects will touch another flat surface in only 3 places. Thus a rigid chassis passing over a warped planar arrangement ( warped by either construction, packaging/transit or installation) will inevitably cause problems.

In the Hornby range it is noticable that the 14XX does not suffer this problem - just the arced up wheels! ( it has a floating rear axle with pick-up).

Have a Model New Year.

Peter A Montarlot

By standing back to back we can be sure not to know what the other party is doing!

Reply to
Peter Abraham

The previous generation of Hornby 6-coupled locos overcame this problem by using slightly smaller diameter wheels with vestigial flanges on the centre axle, so that the wheels could ride over the rail or frog on tight curves. Same with the 6-wheel tenders. Better than the original Hornby Dublo locos that had no flanges on the centre axle. Both the drivers and tender wheels of my newer Black 5 protest on tight curves.

Of course the 9F prototypically has no centre wheel flanges, but it still has a long wheelbase.

Reply to
MartinS

Nah, youve got far too much ability and knowledge for me to contemplate discussion. Mind you my Bachmann Ivatt 4mt (as mentioned as type with problem) goes round my poorly laid peco second radius points with hardly a murmur at high and low speed. Suprisingly so does the Bachmann Crab - in fact all 3 do. Aw heck, havent got a single modern loco (inc one kit built wot did myself) that doesnt go round peco second radius points - although some bump occasionally at the really dodgy one. Did have to mess around with the B2B and other bits and pieces of some occasionally. Perhaps I've been lucky, or perhaps cos the thread wasnt about curved points, doubt if i'm qualified enough to say. Apologies if have misunderstood any bit.

cheers, Simon

Reply to
simon

Simon, you should never let lack of formal knowlege stand in your way. You have experience and yours is as important as any one else's. I can't boast of how much I paid for the latest offering so very few of my locos are less than 10 years old! The peco point is well expounded and there was a 9F thread just before this on which John (55A) of Hull roundly condemned set track and small radius points.

I have some 20 small radius points of which 2 or 3 give universal problems and 3 locos which malfunction from time to time on this type of points. This does not stop me feeling peed off as I do like to turn my back on occasion knowing that all will be well. I do not disagree with you regarding b-b setting but merely offer that there are many other causes -- I seem to remember that Bachmann & Hornby both gave minimum radii warnings on many models -- just like the real thing really!

Regards

Peter A Montarlot

Reply to
Peter Abraham

Reply to
jimpick67

Reply to
jimpick67

One can be enough to get a loco to stop or hesitate over points. As peter said earlier its only in perfect surfaces or with sprung wheels that theres more than 3 wheels in contact at any time. For BackToBack the distance between the outer edges of the flanges should be

16.5 mm. Flanges are wide rims on inside of wheels. The easiest way to make sure they are near enough is to push a loco through the points. Also make sure the wheels are aligned the same - put loco on its side, gently push top wheels down then see if the wheels at underside are approx in line.

Cheers, Simon

Reply to
simon

Dont worry Peter, I'm quite happy with my results. But do note the OP was talking about stqandard 2nd radius and not curved points - curved are the ones that were condemed for the 9F.

Cheers, Simon

Reply to
simon

To all those who helped with my problem which now seems to be sorted, many thanks and have a good new year. Jim

Reply to
jimpick67

Reply to
jimpick67

Typically on older Hornby: left side via loco driving wheels, axles, chassis and tender coupler; right side via tender wheels, axles and chassis. Opposite wheels are insulated from the axles.

Reply to
MartinS

Cant remember which model, but one has pickups on both sets of tender wheels - one of funiest thing on a layout is watching a tender go round on its own.

Simon

Reply to
simon

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