Noise on curves

[timgray]

Hi

I have recently moved over from Triang super 4 track to peco flexitrack 100 with some hornby second and third radius curves.
I have started to lay the new track on 3 mm cork on top of 12.5 mm plywood.
Yesterday evening I had a run round some of the new track and noticed that on the 3 rd radius curves which ever loco i tried they are extremely noisy, really nice on the straights though.
No problem on the old super 4 track 1st radius curves I should add.
Just wondered if there is a problem with the hornby curves which may mean I have to replace the set curves with peco flexi track.
Loco's I tried were a hornby HST, an old Triang Hymek and a modern 0-4-0 tank engine plus an old Triang Nellie tank engine.
Your thoughts appreciated.

[aleopardstail]

could potentially be the back to back gauge for the wheels is a bit out of spec so they are binding on the track a bit on curves?

with a model on a straight gently move it side to side, should be a bit of give, try again on a curve, may be slightly tighter

[Mountain]

What sort of noises?

[Bigmet]

...old Triang Hymek ... old Triang Nellie tank engine...

These two especially may well be noisy due to the motor worm(s) engaging directly with the axle gear, and the flanges possibly running on the code 100 rail chairs. How worn are the locos you have tried?

...No problem on the old super 4 track 1st radius curves I should add...

The smaller radius means there will be more gauge widening, which probably helps keep the noise down. (Having now no such track or locos of Triang type to trial, there's nothing else I can suggest.)

...Just wondered if there is a problem with the hornby curves which may mean I have to replace the set curves with peco flexi track...

Best avoided. When Peco introduced their flexi track it was suggested as suitable for forming curves of 24" radius or greater. It is possible to form smaller radii, but greater care is required to prevent gauge narrowing, constant radius and avoidance of 'dog legs' at rail joints. Essentially if set track radii are required use set track...

...Your thoughts appreciated...

Do you have a loco to test, that is of all new design, introduced since production moved to China? Mechanism refinement has improved significantly over the last 25 years.

[timgray]

Ah had not thought to check the back to back, I assume its the same on peco flexy as the super 4.

I have a up to date Tornado Loco and a Queen Elizabeth which I will try on Friday when I have a chance to get the rest of one oval fitted to the board.

Thanks for your help folks will ley you know how it goes.

[Bigmet]

... back to back, I assume its the same on peco flexy as the super 4...

Items made to run on super 4 and earlier track have smaller back to back to back, (or even variable back to back due to a wheel loose on the axle) and Hornby continued with this on at least some product while manufacturing in the UK, until the move to China and the gradual transition to RP25ish wheelsets with 14.5mm back to back.

It's over a couple years ago I last found a Triang Weltrol, and there was no way it would run on Peco code 100 flexible track. At least it is easy on wagons, out with the wheelsets, fit brass bearings, current Hornby 3 hole discs in, done.

[aleopardstail]

... back to back, I assume its the same on peco flexy as the super 4...

Items made to run on super 4 and earlier track have smaller back to back to back, (or even variable back to back due to a wheel loose on the axle) and Hornby continued with this on at least some product while manufacturing in the UK, until the move to China and the gradual transition to RP25ish wheelsets with 14.5mm back to back.

It's over a couple years ago I last found a Triang Weltrol, and there was no way it would run on Peco code 100 flexible track. At least it is easy on wagons, out with the wheelsets, fit brass bearings, current Hornby 3 hole discs in, done.

found one of my Railroad style coaches yesterday won't go through C75 points, or I suspect C100 - the old square axle wheels, had a DVT some years back that saw a PECO point as "I will now lay down on my side" every single time.

checking this one coach doesn't like the tighter curves I have either

[Bigmet]

...the old square axle wheels...

I had forgotten about those, never having bought any when they were current product, I'd guess they were released while I was busy pursuing career etc..

A friend had a train worth of the all-steel Pullman cars, and on learning I had a layout asked could he bring them over for a run, (to which naturally I agreed as his own days of having a layout were long past, they had moved to a small flat suitable for his wfe's disabilities).

I had never seen the square axle wheelsets before, and the metal tyres were falling off some, hinting at some dimensional movement. Anyhoo, between securing tyres and discarding the unrecoverable wheelsets I found a route where a train of eight would run successfully. George wasn't having that, he wanted all twelve running, and through the curved roads of the point work into the terminus. They fell off all over the place, though the wheelless ones I quickly made into runners by installing the Bachmann coach wheelsets I happily had available, sailed along. (An all Peco code 100 layout, mostly large radius and a few medium points, no crossings, slips, curved points, 36" radius on the passenger routes, hardly 'challenging'.)

[Mountain]

... back to back, I assume its the same on peco flexy as the super 4...

Items made to run on super 4 and earlier track have smaller back to back to back, (or even variable back to back due to a wheel loose on the axle) and Hornby continued with this on at least some product while manufacturing in the UK, until the move to China and the gradual transition to RP25ish wheelsets with 14.5mm back to back.

It's over a couple years ago I last found a Triang Weltrol, and there was no way it would run on Peco code 100 flexible track. At least it is easy on wagons, out with the wheelsets, fit brass bearings, current Hornby 3 hole discs in, done.

found one of my Railroad style coaches yesterday won't go through C75 points, or I suspect C100 - the old square axle wheels, had a DVT some years back that saw a PECO point as "I will now lay down on my side" every single time.

checking this one coach doesn't like the tighter curves I have either

If it has the square axled silver seal wheels with the metal tyres, it is not Railroad as it pre-dates Railroad. Railroad items used these older mouldings after the move to China and the Railroad range was a simplified budget version of them. What you have is the genuine origional Hornby range manufactured in Margate that sold back in the 1980's or just before.
The silver seal wheels were designed for use with the older Hornby track and Peco Setrack track (Code 100 during that time) and actually Peco Streamline, were also designed with these tollerances in mind. (One may have struggled to run "Some" older Triang items through the Streamline range, but it worked fine with the silver seal wheels that Hornby made, and their older code 100 settrack even coped ok with older Triang (Though I found easing things a little with the point flangeways helped).

But back to what you have.

Your Hornby Margate built silver seal wheels will need replacing if you want to use the finescale code 75 track. The likes of the old Mainline items which were built to the finer scale from the start will be ok through them, but most other earlier items will not. Re-wheeling is usually required. (Do not chuck the old wheels as there are plenty of us modellers who find them useful as I amd others either build our own track and models to our own preferred tollerances, etc. Or you can use the old wheels for a depot display etc. Never chuck old wheels! They are useful!)

New wheels are the best upgrade for an older item of rolling stock. Second to that are using a different type of coupling. (If one plans to use Kadees, then be careful which type of new wheels one goes to buy, as the metal axles tend to be attracted to the Kadee magnets.. Other coupling types are uneffected by wheel choice, even if they use magnets under the track such as Sprat&Winkles etc). Other than that, go get some fancy new wheels! Hornby replacement metal wheels are actually really good, though remember that their coaches are built with 12.5mm (One can use 12.6mm as there is hardly any difference) wheels so if one tries to fit the more prototypical 14mm wheels instead, the coach will sit just over 1mm too high. It will work and run fine but will be noticable as the roof will sit a little higher than ones other coaches.
For the ultimate in wheel replacement upgrades, top hat brass bearings will (If fitted correctly) improve the ride further as spin those wheels and they just keep spinning for ages! Fitting the bearings means drilling out holes into the axles and filling them later and painting, so is not quite as simple as just drilling holes. (Not to say I bothered to fill the holes on my 00 gauge stock that I fitted the bearings to! Was a job I had not got around to finishing as I was happy with them as they were).

[aleopardstail]

oh those wheels are for replacement without question, I have one rake of four of them with more modern metal wheels, one axle with a resistor per coach (will eventually be replaced by spring pick ups for lighting), one rake of three with plastic that have yet to be replaced and the one evil coach with these utterly terrible wheels

weird bit, the DVT was part of the 1980's era IC225 set.. the coaches were fine as was the 91, just the DVT that was a pain

so far its the only bit of stock to have a problem with the C75 track

[timgray]

Seems to me to be something to do with the modern plywood. So my layout has doubled in size one half used the original marine ply which I was told is no longer available and the new half uses exterior grade plywood (seemed cheaper to me.)
Now I have one complete oval loop of track fitted and running on 3mm cork incidentally, the difference on the new plywood is extremely noticeable.
Any loco on the good old marine ply is as quiet as a mouse along the straight and round the curves however when running over the new stuff its noticeably noisier particularly on the 3rd radius curves.
I wonder if there is some difference in the make up of the ply and it is acting as a an amplifier, more to the point is there anything I can attach to the underside of the ply to make it quieter such as sheet of polystyrene or ???

[aleopardstail]

Seems to me to be something to do with the modern plywood. So my layout has doubled in size one half used the original marine ply which I was told is no longer available and the new half uses exterior grade plywood (seemed cheaper to me.)
Now I have one complete oval loop of track fitted and running on 3mm cork incidentally, the difference on the new plywood is extremely noticeable.
Any loco on the good old marine ply is as quiet as a mouse along the straight and round the curves however when running over the new stuff its noticeably noisier particularly on the 3rd radius curves.
I wonder if there is some difference in the make up of the ply and it is acting as a an amplifier, more to the point is there anything I can attach to the underside of the ply to make it quieter such as sheet of polystyrene or ???

likely the resin glue in marine ply is waaay better. never even thought of that as I've always had to put up with the rubbish stuff.

for the underside there may be a solution, not polystyrene though, inside of car doors gets a rubbery pad, quite heavy, stuck to it. and I do mean stuck to it, glue bonded over the surface of the pad. it is there to add weight which dampens vibrations. depends how wide the gaps are between supports. these things are heavy but not heavy if that makes sense maybe 400-500g, key bit is they are flexible so don't rattle themselves

if you can get them can try with bean bags on top of the board and see if that helps (maybe even bags of sugar or flour) if that helps may be worth trying to find something to stuck under the board

[timgray]

Sounds an idea I will see what I can find. I am getting use to it though!!

[Bigmet]

...Any loco on the good old marine ply is as quiet as a mouse along the straight and round the curves however when running over the new stuff its noticeably noisier particularly on the 3rd radius curves.

Marine ply is more compliant than building grade ply. For a boat, the ply has to flex and form with no loss of strength when skinning hulls, and then stand up to yet more flexing when bouncing about on the hoggin. These characteristics mean that the vibration of a model railway mechanism is better absorbed before it can couple with the air mass to be apparent as sound.

Regular ply is more like a taut drum skin. The best way to reduce the noise output is to reduce the surface area: lay the track on a strip of ply little wider than the width of the track formation. Makes a big diference - oh, and it's cheaper...