file that frog!

[David62]

 Hi folks good morning to you all!

 

  Being a newbie to DCC  but not DC  I have since discovered  on being now DCC that  most of the track  points in particular have raised frogs and narrow slipways? especially  for the bigger locos  like the 66's and the 40's who i have found derail  at most of these points even on the express points at low speed! I have since discovered also even running at very slow speed position 1 on the Elite  they derail even worse causing the red light to come on and the panic button pressed till i rerailed  the loco.

using a very mallI have filed the frogs level with the track on one of the express points and widened the channel on all the frogs on that point and hey presto  it worked!  even at very low speed all three 66's  ran through it no problem  along with the 37 which i found derailed even easier on it went through no problem    Hornby  WHY?

 

 

Sorted!

 

 

[Grovenor]

Did they not derail the same on DC?

[David62]

 Hi Mate yeah they did it on the Hornby DC too!   i changed to insulfrog  Bachmann express points which were Better qaulity  but they still derailed.  i checked the Hornby point electroclips at slow speed which i thought were the problem at first  raising the wheels on the bogies as they hit the points?... but it was the raised frogs!

[ITG]

I had a Hornby Railroad class 40, on Peco streamline points (both electro frog and insulfrog), and occasionally the loose 2-wheel artificial  ‘bogie’ at the end of the 6 driving wheels would derail at some points, but only ever inconsistently so. No other loco, steam or diesel, did this, although the class 40 was the only 2 x 8 wheel loco. Tbh, I sold it because of that.

But it’s difficult to see how a derailing problem is anything to do with Dcc v dc. Are you sure you points are dead level, and equal force applied to however you’ve fixed them down? I have found track pins unevenly in, can cause the tiniest movement in a point as a loco passes, which can cause poor pickup.

[TheSignalEngineer]

Most problems I have had like that have been inconsistent back to back setting of the wheels on rtr stock. All now get checked on delivery. Historically my worst for derailing was the old Joeuf Class 40, cured by changing the leading wheels on each bogie and adding some lead strip to the carriers of them. 

The instances caused by track problems were one set of points where the baseboard had distorted causing the frog which was right on top of a bracing strut to be raised slightly above the ends and another set where the electrofrog wiring had got trapped under a sleeper with similar effect. 

[GoingUnderground]

So if the same locos derail on DCC and DC, and on Hornby and Bachmann points you have to ask yourself "What's the common feature?" And the answer has to be the derailing locos themselves, not helped by the raised frogs. It sounds to me like problems with the back to backs or possibly the wheels having insufficient vertical play so that when the centre wheels go over the raised frog, that is sufficient to lift the flange on the leading wheel above the rail head and it runs off the rails. Or the flanges might be thicker than expected and the pinch with the check rail is lifting the centre wheel so that the front wheel is again lifted above rail height.

[DCB]

What radius are these so called express points?   I have found its possible to get derailments at very low speed which don't occur at ordinary line speed.  I would suspect inconsistent back to back settings or something obstructing the wheels from moving sideways or even up and down. Up and down play or lack of it caused my T9 to derail constantly and took me about 3 years to finally cure..

[Wheatley]

Back to backs would be my first check too, especially if it's the same locos doing it. 

 

The DCC/DC thing is a bit of a red herring, the only difference should be that a derailing loco will trip out DCC if it causes a short whereas on DC it will just plough on (unless you have one of those dreadful silver super-sensitive Hornby trainset controllers. 

[David62]

Hi folks  thank you for all your replies..  i  managed to locate the problem!  that one L/H express point R8077 had a very slight twist across its length!   I finally removed it and replaced it after finding it had the minutest  twist at the point motor switch end. testing it with a piece of new A4 paper as a shim  it slipped under the point motor switch end with a slight weight on top!   all the rest of my points were ok!  all my points frogs were filed when it was just that one R8077!  they do run over them smoothly now!  if i had  just tested them all  beforehand!! £14.99 a piece!!  (Hornby)  i have the Bachmann 8077's  they were perfect...  all those years away from the hobby ..or is it my age!??

[TheSignalEngineer]

1 hour ago, David62 said:

...  all those years away from the hobby ..or is it my age!??

When I returned to layout building I went over to Code 75. It is much more flexible in all directions that Code 100 and I found laying was much more critical with the more modern track. I had a regular problem with derailments on one turnout and found it was slightly dipped about half way along on one side.

My method now is the hold the track in line with drawing pins at the sleeper ends then lightly glue in place using a strip of glass lightly weighted on top of it until it has dried. After testing the if there is a problem the track can be lifted with a palette knife if necessary thenb re-leveled. In the case of a slight dip I just ease the knife under the sleepers then pump in a small amount of PVA to fill the void. Once you have got it right ballasting will hold it permanently.

 

[David62]

Hi Mate  great idea very ingenious.. after being away for a long while from model rail and used to DC and the zero 1 years ago!   code 75  is that a better qaulity rail track?  I have a gwr prairie which is doin my head in with its stop start .. stop start   i removed the  chip (youchoos) and away it went like a bullet on DC!!    i did notice that it has a lot of play on the track  would code 75 be better?

 

 

David

[DCB]

Should be worse on code 75 if it has a lot of play on code 100.  75 has tighter flangeways so if the loco is a bit narrow to gauge, as much Hornby historically has been, it may well climb over the check rails instead of passing through.   It should be OK if its a New "New" Hornby Prairie but the pre "New" New Hornby Prairies were tight to gauge and the previous ones were worse with traction tyres and copious slop in the driving axles, prior to that they were even worse and the preceding Airfix iteration even worse than that.   We had virtually all the various iterations, most now gone on eBay, and one brand new new one awaiting weight as it has difficulty puling the skin off a cold coffee.

[David62]

Good afternoon David...  cheers for the info and its much appreciated!   i managed to get it going last night again after removing the dcc unit  i had it on the DC  and it flew away like a bat out of hell so i ran it up and down the straight for 20 mins backwards and forwards and then re-installed the chip and it seems to have done it the world of good!  it still stalls at very low speed on the Elite,  up a couple of notches on the speed and it seems to be better though...  theres a lot of play on the track with this loco as ive had to push it sideways a tad then it picks up again?  I checked the pickups  all 6 of them and they seem to be ok and all the wiring too!  a lot of money to buy this loco combined with the youchoos multi function chip £235.. for that amount i want this loco working for a living Lol  makes me wonder if i had bought the DCC RTR version would i be getting the same grief??

[Sir TophamHatt]

Do you have a photo of where you filed the points down?

I know where the frog is but a specific arrow on a photo would be good too.
Mine seem to be fine.

[David62]

   the red arrows are the raised short plastic mouldings onto the rails   i found that  the shallow wheeled  bogie types class  40,66,37,20 etc hit these and bounce quite hard! especially at slow speeds.

 so i filed them down using a small flat file till the plastic was level with the track  it helped a lot! now they dont bounce at all.,the locos just breeze through!  I used a small model tri square to keep a check on the level . check the  Y channel too (blue arrows)  the plastic guard rail (green) on either side inside the rails does not help either making the bogey 'climb' onto the rail these got filed too between the rails very carefully  the (H) standard straights are just the same, but these are not for the long type locomotves like the 66 and 45's  I changed to Bachmann express points  they're not quite as bad.