Peco Bullhead Points: in the flesh

[St Enodoc]

32 minutes ago, PMP said:

@Harlequin’s suggestion is viable for dead end sections, but may not work for a pilot road in DC operation.

On Shelfie three I have a pilot road, A, fed from a crossover B-C. If I didn’t have a separate isolation section for A, every time I used B as a straight route that suggestion would make A live, and any motive power on it move with standard Unifrog’s. So there may still be a need to have a dedicated isolation section where you regularly hold locomotives.

See time lapse for example of what I mean.

Wouldn't that be true whichever type of frog point C has?

[PMP]

18 minutes ago, St Enodoc said:

Wouldn't that be true whichever type of frog point C has?

Indeed, probably confused readers as I forgot to mention I’ve a baseboard joint through A-B too! Apologies for that :)

[martin_wynne]

Access to, and exit from, such a loco spur would normally be controlled by ground disc signals.

 

You can use the signal mechanisms to switch the section feed to the spur on and off.

 

Martin.

[gr.king]

DCC is not a universal practice nor a universal preference / aspiration. Self switching electrofrog (or insulforg if you absolutely can't/won't do wiring) have been the normal arrangement for many years and are still most convenient for analogue systems. Non-switching unifrog points are therefore most definitely NOT a "Good Thing generally".

[PMP]

7 minutes ago, martin_wynne said:

Access to, and exit from, such a loco spur would normally be controlled by ground disc signals.

 

You can use the signal mechanisms to switch the section feed to the spur on and off.

 

Martin.

The signalling hasn’t yet been decided upon, (semaphore/colour light/mixed) but is unlikely to include functioning ground signals.

[St Enodoc]

7 minutes ago, PMP said:

The signalling hasn’t yet been decided upon, (semaphore/colour light/mixed) but is unlikely to include functioning ground signals.

Coward!

[PMP]

5 hours ago, gr.king said:

DCC is not a universal practice nor a universal preference / aspiration. Self switching electrofrog (or insulforg if you absolutely can't/won't do wiring) have been the normal arrangement for many years and are still most convenient for analogue systems. Non-switching unifrog points are therefore most definitely NOT a "Good Thing generally".

I’m possibly misunderstanding you, but for clarity these Unifrog points, out of the packet are in effect dead frog/insulfrog points. They can be laid as straightforward DC points with no frog polarity change from the pack. If you want to electrify the frog, all you do is connect the wire already assembled to the point. 
 

The Unifrog system is being introduced across the Peco ranges, part of the benefit being retailers won’t need to stock two types of each point, the Unifrog allows a 2 in 1 solution.

Edited June 25, 2022 by PMP
Addition of 2nd para

[PMP]

1 minute ago, St Enodoc said:

Coward!

🤪

I’m in two minds re the signalling, I like the concept of semaphore last days, and new colour lights, installed but not yet commissioned. Not to mention deciding which ‘company’ the semaphores should be! (M62 corridor)

[martin_wynne]

8 minutes ago, St Enodoc said:

but is unlikely to include functioning ground signals

 

You don't need a functioning ground signal on the baseboard. You just need a functioning lever in the signal box. 🙂

 

Martin.

[Harlequin]

4 hours ago, gr.king said:

DCC is not a universal practice nor a universal preference / aspiration. Self switching electrofrog (or insulforg if you absolutely can't/won't do wiring) have been the normal arrangement for many years and are still most convenient for analogue systems. Non-switching unifrog points are therefore most definitely NOT a "Good Thing generally".

 

They may not suit everyone but in general I maintain that they are a Good Thing because, by not attempting any electrical switching:

• Any switching function required is delegated to a properly designed electrical device. It no longer relies on a side-effect of blades touching stock rails out in the open where it can be affected by dust, gunge, cat hair, paint and ballast.
• The turnouts themselves are more reliable because all the rails apart from the very tiny "frog nose" are permanently wired.
• Edit: There's no longer any possibility of point blades and external switches causing momentary shorts if they operate at different speeds.
• For most people's use they will need no modification before installation, unlike the kinds of mods people often do to Electrofrog turnouts to overcome some of the issues raised above.
• It's not difficult to arrange sections of track to be switched in other ways - it's just different from the old familiar practice.

The issues with some rolling stock shorting when passing through Unifrog turnouts really suggests that the stock is at fault more than the turnouts, IMHO. I.e. Out-of-range B2Bs, badly designed crabbing ponies, wider flat-treaded wheels than normal and flangeless wheels that can ride over adjacent rails. That thought is supported by the fact that, having seen the feedback on the Large Radius turnouts, Peco didn't change their basic design concept for the Unifrog crossings and slips.

So I would definitely be looking at my stock before doing anything drastic to the bullhead turnouts, slips and crossings!

 

Edited June 25, 2022 by Harlequin

[PMP]

53 minutes ago, martin_wynne said:

 

You don't need a functioning ground signal on the baseboard. You just need a functioning lever in the signal box. 🙂

 

Martin.

I’ve got one it’s called an isolating section switch on the control panel.

[PMP]

35 minutes ago, Harlequin said:

 

They may not suit everyone but in general I maintain that they are a Good Thing because, by not attempting any electrical switching:

• Any switching function required is delegated to a properly designed electrical device. It no longer relies on a side-effect of blades touching stock rails out in the open where it can be affected by dust, gunge, cat hair, paint and ballast.
• The turnouts themselves are more reliable because all the rails apart from the very tiny "frog nose" are permanently wired.
• For most people's use they will need no modification before installation, unlike the kinds of mods people often do to Electrofrog turnouts to overcome some of the issues raised above.
• It's not difficult to arrange sections of track to be switched in other ways - it's just different from the old familiar practice.

The issues with some rolling stock shorting when passing through them really suggests that the stock is at fault more than the turnouts - out-of-range B2Bs, badly designed crabbing ponies, wider flat-treaded wheels than normal and flangeless wheels that can ride over adjacent rails. That thought is supported by the fact that having seen the feedback on the Large Radius turnouts, Peco didn't change their basic design for the crossings and slips.

 

Wholeheartedly agree, personally I’ve never been convinced by the blade/stock rail argument. Both Albion Yard and Shelfie1 relied on blade contact only and neither exhibited any issues. 

 

The point regarding stock ‘faults’ is well made and valid. If there were significant failings in the design, we’d undoubtedly have heard about them regularly on here and other media, eg FB groups. The points have been out for roughly five years (late 2017 release), so there’s been good exposure to them. In the time I’ve had Shelfie3 in test and running, over those five years I’ve not experienced a single short circuit caused by them. As I mentioned yesterday I do have the opportunity to try some equipment I’ve not tested, and I’ll report in due course.

[St Enodoc]

2 hours ago, martin_wynne said:

 

You don't need a functioning ground signal on the baseboard. You just need a functioning lever in the signal box. 🙂

 

Martin.

You do if the signalman and driver are not the same person.

[The Stationmaster]

8 hours ago, PMP said:

@Harlequin’s suggestion is viable for dead end sections, but may not work for a pilot road in DC operation.

On Shelfie three I have a pilot road, A, fed from a crossover B-C. If I didn’t have a separate isolation section for A, every time I used B as a straight route that suggestion would make A live, and any motive power on it move with standard Unifrog’s. So there may still be a need to have a dedicated isolation section where you regularly hold locomotives.

See time lapse for example of what I mean.

It can also depend on what you regard as the crossover or if you work the three point ends by 3 different levers and where you put your rail isolating breaks plus which end you feed from.  

 

Logically siding A would have to be fed from the facing point in the incoming line (call it D for convenience) so if D is wired with a live crossing and C is also wired with a live crossing siding A will self isolate.  What then needs to be avoided is any sort of feed from the toe end of point B so isolation is required between points C and B which would ensure that no current switched by B can get to siding A.

 

If you then make the crossover between C and B stand normal with B set for the straight road and C set towards the siding the siding will only become live with D set towards C (which is what you need anyway in order to get to/from siding A.  If crossover B/C is set reverse Siding A will be isolated and you will in any case need to separately feed both rails on the toe side of B in order for a train to depart from that platform so that feed would also be used to allow a train to arrive at that platform.

 

A lot f point wiring can makea lot more sense when looked in the light of the locking between points.   On this layout D normal (straight road) would lock B/C normal (straight road at B/siding A at C).  The corpllary is that D reverse would release B/C to be reversed.  (i'm assuming 100% live wiring of the crossings (aka frogs).

 

An interesting things with the Unifrog points is that in altering them to make the crossing live and switchable together with their existing insulating joints coming out of the crossing  in a some situations you don't need insulating fishplates between the two running lines of a double crossover (but you do of. course need to snip some of the factory installed bonding wires.

 

[The Stationmaster]

7 hours ago, PMP said:

🤪

I’m in two minds re the signalling, I like the concept of semaphore last days, and new colour lights, installed but not yet commissioned. Not to mention deciding which ‘company’ the semaphores should be! (M62 corridor)

Don't forget that you will also need to decide which Region/period the colour lights will represent 😇

[PMP]

1 hour ago, The Stationmaster said:

Don't forget that you will also need to decide which Region/period the colour lights will represent 😇

I should maybe start a S3 layout topic! But aiming at 1968-82 and Midland/Eastern region/s

[Kirby Uncoupler]

 

 

 

Hi Everyone,

     When the new Peco Bullhead points first appeared a few years ago, I liked the overall look of the points, but not the triangle of metal forming the "Unifrog", it looked alien. So I experimented on these two large left-hand points shown here, well I would wouldn't I.

   On the point top and right of the pictures, I removed the moulded plastic rail spacers and soldered the rails together, making the frog a solid all-metal type, with two new cuts in the switch rails, to isolate the frog, like on a regular live or dead frog point. There was a fair amount of work involved, and it crossed my mind that it would just as easy to carry on building points from scratch, so this exercise was not repeated.

       Looking for a quicker and easier fix, on the other point seen left and below, I filed down each of the four plastic gaps very slightly, then applied gold paint from a pen to the plastic only, the filed recess should stop the paint wearing off too quickly (fingers crossed). I was quite pleased with the second method, and have now applied it to many more of these new points, including three of the just-released double-slips, at a glance the plastic gaps have disappeared.

                                Cheers, Brian.

 

[Kirby Uncoupler]

Regarding isolation switches, they're obviously not required, or at least not essential, on DCC operation, but on analogue 12v DC operation your Unifrog point layout will need switches for each siding, if stabling locos, unless operating as a "one engine in steam" yard. The old method of siding isolation using point blades is simple and convenient, but not foolproof, I find it safest to have one or more on-off switches for each siding.

    What can happen with conventional point blade isolation (not Unifrog), is take two sidings with one loco parked on each track, if the point blade hasn't made proper contact, you end up with a 'M' shaped electrical circuit, and if you apply power, both locos will move at around half-speed. What has happened, is the two locos have worked in series, the positive current runs down the stock rail to Loco A, passes through the motor, back up to the common frog, back down to Loco B, through that motor, and then returns back as negative up the other stock rail. Individual siding switches eliminate this potential operating hazard.      BK

Edited June 26, 2022 by Kirby Uncoupler
Added word

[dasatcopthorne]

[Kirby Uncoupler]

Two further issues, 

     A fellow RMwebber has asked whether the metallic pen paint shorts out the gaps(?), well not in my experience, and I did test the gaps for leakage with a meter.  The gold pen that I used, was from WH Smith, which looks very similar to the product by Pilot, and Pilot refer to it as "ink", so maybe there's the difference? We don't want any conduction here, i'd better test some Humbrol metallic paint as well, to check it's electrically dead when dry?

     I forgot to mention, that as can be seen, I mount my points on thin card, just old re-cycled food packaging like corn flake or pizza boxes, it gives a bit of sound insulation, and a ballast shoulder, plus with just a few dabs of glue underneath, it makes removing points easier, with less damage. I used to use cork years ago, then went through my foam rubber phase, followed by my terrific idea of using re-cycled bubblewrap (bubbles down, leaving a smooth top for ballast), which ended up as a total disaster. Trying every type of glue on the planet, including impact and superglue, the bubble side would just not be gripped permanently, the flat side was not much better. Now i'm stuck with a mountain of secondhand bubblewrap! What about sound or loft insulation???

       I really need to paint those check rails rusty.          BK

 

[Kirby Uncoupler]

Here's some more fumbling around with the points, this time spludging some paint on to the rails and chairs. Two big advantages of not having to rely on point blades for electrical continuity, is no problem with dirt and dust causing unreliability on the board top, and secondly you can merrily paint your point blade sides to match, although of course let the first blade position dry properly, before attempting the other position, or you'll end up with a solid point, ha,ha. Rummaging through my paints, I chose Humbrol No.9, which is actually a gloss paint, so I matted it down with talcum powder, it don't 'arf smell nice! There's no hard and fast rules about track colours, but regularly used lines tend to be a Dijon Mustard colour, less used lines are more orangey-red from the build-up of rust, abandoned lines can be anything from dark brown to even black. I'm no expert, but I think it's all to do with the flexing of the rails (in use), microbes of rust fall off, giving a lighter appearance. Maybe it's like the White Cliffs Of Dover, in their shiny white, where old chalk constantly falls away, revealing fresh new chalk behind?

    Some people prefer to paint their rails after laying and ballasting, but I find it easier this way, to save leaning over an awkward baseboard.

 

 

This particular point will be a facing point on a passenger track, so I have added a DIY locking bar cover, from spare plasticard. I used to think these were centred over the tiebar, but more and more photos have shown them to be off-centre, giving greater protection for traffic running towards the frog.

                                                                     Cheers, Brian.

 

[Kirby Uncoupler]

On 25/06/2022 at 08:25, PMP said:

@Harlequin’s suggestion is viable for dead end sections, but may not work for a pilot road in DC operation.

On Shelfie three I have a pilot road, A, fed from a crossover B-C. 

 

May I suggest to Mr.PMP, that besides a separate isolation section for the loco siding, prototypically it also needs a trap point at position A, to hinder any runaway loco, and protect the passenger running lines. Crews at King's Cross used to tell me, that some diesel locos could runaway after a period of standing, Class 40s were among the worst offenders, and had to be "scotched" with wooden wedges (chocks) between wheel and rail. What do fellow RMwebbers think?    BK

[PMP]

It does need a trap point there, the problem is that there’s also a baseboard joint and I can’t find a glue robust enough to fix C&L chairs permanently to the Peco sleepers. I’m trying drilling and pinning to see if that works.

 

Theres an alternative painting method here too.

https://albionyard.com/2022/03/29/transformation-tuesday-paint/

[The Stationmaster]

35 minutes ago, Kirby Uncoupler said:

 

May I suggest to Mr.PMP, that besides a separate isolation section for the loco siding, prototypically it also needs a trap point at position A, to hinder any runaway loco, and protect the passenger running lines. Crews at King's Cross used to tell me, that some diesel locos could runaway after a period of standing, Class 40s were among the worst offenders, and had to be "scotched" with wooden wedges (chocks) between wheel and rail. What do fellow RMwebbers think?    BK

And it would have to be a wide-to-gauge trap because otherwise whichever way a 'trapped' loco goes it would foul a running line.   A dummy trap would probably be the best answer in the situation on the layout as it stands.  My pics below show an example of a w-t-g trap (albeit in a NSW setting and as part of a Y point but they hopefully illustrate the principle although the arrangement of point machines and detectors is rather different from usual British methods).

 

As a matter of possible interest all the EE Type 4s (class 40 in later years) carried they own sets of scotches at one time after the need for them had been learned the hard way plus there was an Instruction taht they were always to be scotched when stabled with the handbrake applied .  As far as I know they were the only BR mainline diesels which were so equipped all other types having reliable handbrakes (although I didn't see all types so maybe there were some different ones that never came our way?).   However if a loco was stabled and incorrectly secured only by the straight air brake those brakes would gradually leak off - which led to a number of runaways.

 

 

 

[martin_wynne]

41 minutes ago, PMP said:

the problem is that there’s also a baseboard joint and I can’t find a glue robust enough to fix C&L chairs permanently to the Peco sleepers

 

Try brushing 2-part fibreglass resin around the chairs and sleepers at board joints when using plastic track parts. Sets very solid, and all gets hidden under the ballast.

 

 

Martin.