Wright writes.....

[lezz01]

8 hours ago, dibateg said:

I found that as I've got older, I've become more sensitive to the fumes from the various substances we use, particularly Humbrol paint and Mekpak.

 

I'm on a project to build 28 4mm scale turnouts for Bala Junction, Bala and Trevor, oddly Butanone doesn't seem as bad to me as Mekpak. But something had to be done to get rid of the fumes and enable mass production, so I rigged up an extractor system - the hose plugs in to an exhaust vent mounted in a piece of ply that 'clips' in to the fan light of the window. 

 

Excuse the chaotic workbench...

 

 

Regards

Tony

Strange, chemically Butanone and MEK are the same thing they are both C4H8O or CH3C(O)CH2CH3 to be exact and as far as I know Butanone as sold for modelling is slightly stronger than MEKPAC by around 4% so I would expect Butanone to have more of an effect on you than MEKPAC. I buy mine in 1litre bottles at 99% strength and dilute it down to 50% with water myself.

Regards Lez.

[St Enodoc]

1 hour ago, lezz01 said:

Strange, chemically Butanone and MEK are the same thing they are both C4H8O or CH3C(O)CH2CH3 to be exact and as far as I know Butanone as sold for modelling is slightly stronger than MEKPAC by around 4% so I would expect Butanone to have more of an effect on you than MEKPAC. I buy mine in 1litre bottles at 99% strength and dilute it down to 50% with water myself.

Regards Lez.

I'm sure I've read many times that Slater's MekPak is a cocktail of various chemicals, not pure MEK/Butanone.

[lezz01]

12 minutes ago, St Enodoc said:

I'm sure I've read many times that Slater's MekPak is a cocktail of various chemicals, not pure MEK/Butanone.

It seems that MekPac is not Butanone anymore but slaters don't tell you what it actually is on the bottle. I'll stick with Butanone if anyone asks me cos I know what's in it.

Regards Lez.

[St Enodoc]

1 hour ago, lezz01 said:

It seems that MekPac is not Butanone anymore but slaters don't tell you what it actually is on the bottle. I'll stick with Butanone if anyone asks me cos I know what's in it.

Regards Lez.

Me too.

[gr.king]

I remember being told many years ago that Mekpak, for "safety" reasons, was no longer purely Methyl Ethyl Ketone or Butanone, if indeed it ever was, but the (therefore potentially misleading) name had been retained unchanged. I believe that some "discerning" users immediately noticed that the smell had changed, and in some cases the performance.

[polybear]

I believe that the mix of Mekpak was changed after George(?) Slater was found unconscious in the factory one day, after being exposed to the fumes.

[Ollie K]

On the poignant subject of recording memories while one still has the chance, late last year I finally got round to sitting down with my grandfather and 'interviewing' him about life as a New England fireman in the early 1950s. The conversation was recorded into a dictaphone and filmed on a GoPro for posterity. 

 

I found it immensely rewarding, though I kick myself for missing my chance with other grandparents to record their experiences of the war and serving in the armed forces. I'd heartily encourage anyone who's also thought about recording a memoir to give it a go.

 

I'll pop a link to the write-up here as it may be of interest to ECML folk. To think Grandad was bowling through the 1:1 Little Bytham all those years ago!

 

https://www.tracksthroughgrantham.uk/railway-life-at-grantham/loco-department-staff/patrick-kew-a-peterborough-fireman/

 

[lanchester]

6 hours ago, gr.king said:

I remember being told many years ago that Mekpak, for "safety" reasons, was no longer purely Methyl Ethyl Ketone or Butanone, if indeed it ever was, but the (therefore potentially misleading) name had been retained unchanged. I believe that some "discerning" users immediately noticed that the smell had changed, and in some cases the performance.

A quick aside on Methyl Ethyl Ketone. Many years ago now I visited a company that manufactures the printers that put those purple batch numbers and sell by dates on the bottom of drink cans etc. They had a problem - in Europe, opinion was very against using MEK as the solvent because it is a potential carcinogen, so wanted to use one of the alcohols. In the US, however they were relaxed about MEK but dead against alcohol on the grounds that the workers might drink it. You can't win sometimes!

[Steamport Southport]

People do realise you can get odourless super glue and plastics glue?

 

https://www.hobbies.co.uk/deluxe-materials-low-odour-and-odourless-glue-pack-3

 

 

 

Jason

[Bucoops]

35 minutes ago, lanchester said:

A quick aside on Methyl Ethyl Ketone. Many years ago now I visited a company that manufactures the printers that put those purple batch numbers and sell by dates on the bottom of drink cans etc. They had a problem - in Europe, opinion was very against using MEK as the solvent because it is a potential carcinogen, so wanted to use one of the alcohols. In the US, however they were relaxed about MEK but dead against alcohol on the grounds that the workers might drink it. You can't win sometimes!

 

America, and California especially, being rather fond of labelling seemingly anything as a carcinogen.

 

[Dunsignalling]

8 hours ago, polybear said:

I believe that the mix of Mekpak was changed after George(?) Slater was found unconscious in the factory one day, after being exposed to the fumes.

I'm pretty sure MekPak has changed at least once more since then.

 

I stopped using the stuff that smelled like BR loo cleaner as it only seemed to work with one or two kinds of plastic, but the current brew seems more versatile (and fragrant when one does get the odd whiff of it).

 

Butanone is my go-to for most plastic kits and sheet construction in 40-thou. and over. Horses for courses for other stuff. I prefer MekPak or Limonene for thinner sheet work and Plastic-Weld for jobs like repairing the Parkside tie-bar I snapped this morning, where it seems more effective than anything else. Plastic Magic also comes in  handy for things that need a bit of "wiggle time", as it seems a bit thicker and slower to evaporate.   

 

John

 

 

Edited February 26 by Dunsignalling

[Dunsignalling]

3 minutes ago, Bucoops said:

 

America, and California especially, being rather fond of labelling seemingly anything as a carcinogen.

 

 

A good rule of thumb is that most stuff can be carcinogenic if one is exposed to enough of it.

 

[MJI]

7 minutes ago, Bucoops said:

 

America, and California especially, being rather fond of labelling seemingly anything as a carcinogen.

 

Do not eat your razor saws.

 

They do have warnings.

Edited February 26 by MJI

[Bucoops]

1 minute ago, Dunsignalling said:

 

A good rule of thumb is that most stuff can be carcinogenic if one is exposed to enough of it.

 

 

I have no doubt. Which makes Proposition 65 even more pointless.

 

[polybear]

1 hour ago, Bucoops said:

 

America, and California especially, being rather fond of labelling seemingly anything as a carcinogen.

 

 

Whilst working in S. Korea in 2001 I was reading the blurb on a can of Pepsi whilst sitting in a Bar one evening.  Then I noticed a warning along the lines of:  "Has been linked to an increased incidence of Cancer in lab mice....."

The warning was gone when I was last there (2018/19 IIRC).

[TrevorP1]

1 hour ago, Steamport Southport said:

People do realise you can get odourless super glue and plastics glue?

 

https://www.hobbies.co.uk/deluxe-materials-low-odour-and-odourless-glue-pack-3

 

 

 

Jason

 

As far as odourless CA is concerned I found the hard way that the 'fumes' are just as obnoxious. 

Edited February 26 by TrevorP1

[gr.king]

2 hours ago, lanchester said:

A quick aside on Methyl Ethyl Ketone. Many years ago now I visited a company that manufactures the printers that put those purple batch numbers and sell by dates on the bottom of drink cans etc. They had a problem - in Europe, opinion was very against using MEK as the solvent because it is a potential carcinogen, so wanted to use one of the alcohols. In the US, however they were relaxed about MEK but dead against alcohol on the grounds that the workers might drink it. You can't win sometimes!

For a short while my brother-in-law worked in a factory near Cambridge (Bar Hill) making the printers that add the batch numbers and "best by" dates. His Mk 1 nose detected plenty of airborne MEK.

[Captain Kernow]

22 hours ago, Tony Wright said:

To solder the washers to retain the rods. A paper washer (instruction-thickness) acts as a barrier to solder and also to give a working clearance. The paper is discarded once the rod is secured.

 

 

A close-up. It's vital that solder thoroughly penetrates the joint, meaning this can be later filed down if clearance issues occur.

Hi Tony,

 

I use Romford or Markits crankpins in almost exactly the same way, although I retain coupling rods etc. with small bits of wire insulation until I am totally happy with the running.

 

I then remove all rods, crankpins etc. and then hold each crankpin in turn in the vice, with sacrificial card against both jaws of the vice to protect the brass screw thread of the crankpin.

 

I then solder the washer onto the crankpin exactly as you do and then file the surface smooth, while the crankpin is securely held in the vice.

 

Before I remove each crankpin from the vice, I file a shallow diagonal cut across the face of the crankpin nut with a thin, fine piercing saw blade. This then gives a way of screwing the completed rod assembly back into the wheel, using a thin-bladed screwdriver and crucially makes removal again for maintenance etc. very easy.

 

With locos with any kind of valve gear, I tend not to do this, for obvious reasons, so if there's a problem that requires the valve gear to be removed, I unsolder the crankpin nut itself.

 

The picture below on my under-construction Cotswold 16XX illustrates the above.

 

Once the rods are painted and weathered, the groove in the crankpin nut isn't so apparent. If it was to bother me, it could be easily filled with a soft filler, such as plasticine, which could be easily removed with the thin bladed screwdriver, if that proved necessary.

 

[Tony Wright]

28 minutes ago, Captain Kernow said:

Hi Tony,

 

I use Romford or Markits crankpins in almost exactly the same way, although I retain coupling rods etc. with small bits of wire insulation until I am totally happy with the running.

 

I then remove all rods, crankpins etc. and then hold each crankpin in turn in the vice, with sacrificial card against both jaws of the vice to protect the brass screw thread of the crankpin.

 

I then solder the washer onto the crankpin exactly as you do and then file the surface smooth, while the crankpin is securely held in the vice.

 

Before I remove each crankpin from the vice, I file a shallow diagonal cut across the face of the crankpin nut with a thin, fine piercing saw blade. This then gives a way of screwing the completed rod assembly back into the wheel, using a thin-bladed screwdriver and crucially makes removal again for maintenance etc. very easy.

 

With locos with any kind of valve gear, I tend not to do this, for obvious reasons, so if there's a problem that requires the valve gear to be removed, I unsolder the crankpin nut itself.

 

The picture below on my under-construction Cotswold 16XX illustrates the above.

 

Once the rods are painted and weathered, the groove in the crankpin nut isn't so apparent. If it was to bother me, it could be easily filled with a soft filler, such as plasticine, which could be easily removed with the thin bladed screwdriver, if that proved necessary.

 

Good evening Captain,

 

Your system obviously works. 

 

One thing I've encountered (though not on my own models) is Romford crankpins working loose over time, resulting in locos jamming up as the pins unscrew. 

 

In the time before Romford drivers were tapped for crankpins, I used to drill a hole which was a clearance fit for a crankpin using a substantial pillar drill. The pin was then secured with the old slow-setting Araldite and left to cure for a couple of days before further work was carried out. Which meant (means) that replacing a crankpin (should it ever wear out) was impossible. I started that process over 50 years ago, and have never had to replace a crankpin.

 

Nowadays (and for many years) I screw the crankpin in as tightly as I can without distortion and then put a tiny bead of superglue over the end of the pin in the back of the wheel. This prevents the pin ever working loose, but might impair replacement. However, I did try releasing a pin by heating its back end with a soldering iron (don't breath!), and that broke the joint. 

 

Since my oldest Bytham locos are still running without ever having a pin replaced (after over 50 years!), anyone who might have to replace a pin will be doing so long after I'm gone. 

 

Some comparisons of possible interest...............

 

 

On the right is Bytham's oldest engine, a K's O4 which I built in 1973 (though not with K's mechanics). It's still going strong, though its pins must be worn a bit by now. Even if it failed tomorrow (half its drivers are old Romfords with no tyres, just a complete Mazak wheel), it owes me nothing. 

 

The A4 on the left (built by Mick Peabody and me from a Pro-Scale kit), though 20 years the O4's junior has probably done more miles since she (KINGFISHER) always hauled 'The Elizabethan' on Stoke Summit. Her crankpins are still intact I'm glad to say. 

 

 

Not quite as old as the O4 (some six years its junior) is this scratch-built O1 (towing a K's ROD tender). This, too, has plain Mazak Romford drivers on one side, with the pins Araldited in, and, so far her crankpins are intact. 

 

 

Of the same vintage as the O1, this part-scratch-built O4/8 has exactly the same arrangement. 

 

Still, at over 40 years old they still keep going; in fact it might be interesting to speculate at what age both locos (and the K's O4) will require new crankpins, because they all still get run - another decade? Another 20 years?

 

Which means that.............

 

 

By the time this O4/7's crankpins wear out (secured by superglue) I'll be 138 years old (at least!). It was finished this year........

 

Regards,

 

Tony. 

 

 

[Tony Wright]

Of some possible idle interest....................

 

 

This is a picture taken looking north along Station Road in Little Bytham, dating from just prior to WW1 after the station had recently been rebuilt with the quadrupling of the ECML at this spot. 

 

Today, as I walked to post a letter, I took a picture from more or less the same spot.................

 

 

Though the (now closed and un-named) Willoughby Arms is still standing to the right and the crumbling booking office is still there to the left, it requires the 'eye of faith' to think that this was once a station/goods yard site. Amazingly, some of the original fencing still stands, as well as a gatepost or two and part of the low wall. 

 

The MR/M&GNR embankment and the bridge in Station Road are still in existence, but Mother Nature has managed to disguise them. 

 

My principal lens is under repair at the moment, but when it's back I'll try and take a similar view on the layout to the early one. 

[Hroth]

The photos remind me of those "The xyz Railway Then and Now" books.  One I have, of the GCR, is particularly distressing.

 

[lezz01]

22 minutes ago, gr.king said:

For a short while my brother-in-law worked in a factory near Cambridge (Bar Hill) making the printers that add the batch numbers and "best by" dates. His Mk 1 nose detected plenty of airborne MEK.

Yep you can always rely on the MK1 nose.

It's the =O to the 2nd carbon atom that makes it smell like that it's correct name is 2 Butanone if it was only a single bond it would be C4H8OH instead of C4H8O and be called Butanol. Carbon has a valency of 4 and Oxygen 2 and they have to use all of their bonds or the molecule would become unstable. It's why Oxygen is O2 and water is H2O the O2 as a chemical formula would be O=O and H2O would be H-O-H. The equals sign representing a double bond and the minus sign a single bond. In organic chemistry  molecules are held together by covalent bonds which means that the electrons in the outer shell of an atom are shared between between the atoms in the molecule. In something like Benzine C6H6 the Carbon atoms form a ring  each having 1 double bond and 2 single bonds one to the next carbon atom and one to the hydrogen atom and the electrons whizz around the ring a bit like greyhound at a dog track.

Err sorry I do like a bit of organic chemistry.

Regards Lez.       

[bbishop]

Lez,  I was taught that the benzene bonds were all interchangeable so I drew it as a hexagon with a circle inside. Not my favourite bit of organic chemistry,  much preferred organo-phospherous which was good for clearing a train carriage in the rush hour.

Edited February 26 by bbishop

[St Enodoc]

6 minutes ago, bbishop said:

I was taught that the benzene bonds were all interchangeable so I drew it as a hexagon with a circle inside.

We were taught to do that for A Level in 1972-74.

[Michael Edge]

I always lock Romford crankpins in with Loctite threadlock. They would still be removable from Markits/Romford wheels with the application of a little heat, if you use superglue they will be there forever. I use them in Gibson wheels as well after drilling and tapping them 10BA.

Locking them in the wheels is essential, it can make a real mess of the motion work if they come unscrewed at speed.