Butanone / MEK application?

[Sheffield Midlands]

Silly question perhaps but what methods do you use to apply Butanone / MEK (Plastic Weld) to fix rail chairs to sleepers? I may be applying too much or too much pressure but many look distinctly melted and distorted.

[Miss Prism]

Functional or cosmetic chairs?

 

[Andy Hayter]

AFAIK Plastic weld is not MEK.  However, regardless of that, I use a very fine brush for small components and normal joints.  By small I mean a 000 brush, that having done its job in painting and beginning to lose its hairs has now been promoted to glue duties (so probably closer to 0000.)  Even a small drop left on the tip should not cause a problem but I aim for the brush to be wet but not have a visible drop at the end.

[Sheffield Midlands]

32 minutes ago, Miss Prism said:

Functional or cosmetic chairs?

 

Both

 

9 minutes ago, Andy Hayter said:

AFAIK Plastic weld is not MEK.  However, regardless of that, I use a very fine brush for small components and normal joints.  By small I mean a 000 brush, that having done its job in painting and beginning to lose its hairs has now been promoted to glue duties (so probably closer to 0000.)  Even a small drop left on the tip should not cause a problem but I aim for the brush to be wet but not have a visible drop at the end.

 plastic weld is definitely MEK according to the label.....

 

i guess I need a smaller brush than the 000 that I’ve been using. Wondering if syringes might be good to with a very fine needle?

[Miss Prism]

Are the timbers stained or unstained?

 

[Sheffield Midlands]

12 minutes ago, Miss Prism said:

Are the timbers stained or unstained?

 

a mix of unstained wood ones and plastic/styrene (concrete)

[sulzer27jd]

Apply the solvent to the sleeper and let it run under the chair. It doesn't require much pressure. I find using several gauges and a steady methodical approach of doing two or three chairs and then leap-frogging the last gauge over the nearest is a reasonable method. With wooden sleepers you can actually see the solvent getting drawn under by capiliary action. They generally require a couple of seconds more to get a solid bond.

 

John

[flubrush]

1 hour ago, Sheffield Midlands said:

Wondering if syringes might be good to with a very fine needle?

 

I now use syringes to apply MEK/Butanone when building track with plastic chairs.  I find that I can apply the correct amount quite easily and there are very few fumes compared to using a brush.  You can also pick up and put down the syringe quite easily with one hand - no "brush in bottle" action required with the possibility of spilling the bottle.   The syringes and blunt needles can be got from Ebay - maybe get an assortment of needle sizes to let you decide on what size is best for you.

 

Jim.

[Dave Hunt]

2 hours ago, Sheffield Midlands said:

 

 plastic weld is definitely MEK according to the label.....

 

Not so, Plastic Weld is methylene chloride (AKA dichloromethane) whereas MEK is methyl ethyl ketone - different substances and although both work with polystyrene, only methylene chloride will dissolve acrylics.

 

Dave

[sharris]

6 hours ago, Andy Hayter said:

AFAIK Plastic weld is not MEK.  

 

And as you pointed out in this thread a couple of years ago, even MekPak isn't MEK these days...

What a confusing world we live in if we expect, from experience, a product to do something, and it doesn't do exactly the same thing any longer.

 

[brossard]

I use a cheap old brush to apply MEK.  I'm using Peco chairs and stained timbers.  It all works very well.

 

Check out your DIY store.  I got a liter tin of MEK at my local.  I suspect it is cheaper than buying those tiny bottles from modelling outlets.

 

MEK and Butanone are the same thing.

 

John

[thedman]

MekPak was never in its entire life MEK.

[Izzy]

I have only ever used a good quality sable brush (W&N mainly) for liquid glue, Mek-Pak, Plasticweld etc. My current one is around 10-15 years old, and still with plenty of bristles. 
 

I usually give chairs a few doses in a batch of 3-4 sleepers in rotation before moving on to the next batch. Takes a few mins for the bond to the ply sleepers to fully go off as a rule.  I always slosh a bit of paint ( poster paint mostly) over them and the side of the rail to help key them together later on so don’t really notice any surface melting as such should it occur. But then I probably don’t work to the high standards others achieve.

 

Izzy

[Dave Hunt]

1 hour ago, thedman said:

MekPak was never in its entire life MEK.

 

Yes it was. When George Slater started the business, Mekpak was mainly MEK but after he was found unconscious on the floor one night after a leakage (and was lucky to be found) the formulation was changed.

 

How do I know this? Because I was once a director of Slaters.

 

Dave 

[Sheffield Midlands]

16 hours ago, Andy Hayter said:

AFAIK Plastic weld is not MEK.  However, regardless of that, I use a very fine brush for small components and normal joints.  By small I mean a 000 brush, that having done its job in painting and beginning to lose its hairs has now been promoted to glue duties (so probably closer to 0000.)  Even a small drop left on the tip should not cause a problem but I aim for the brush to be wet but not have a visible drop at the end.

 

clearly says MEK on it.... 5-15% but also has Methylene Chloride in it

 

 

[Andy Hayter]

Except that that is Plastruct and not plastic Weld made by EMA which as already stated shows its composition is methylene dichloride.

[Sheffield Midlands]

5 hours ago, Andy Hayter said:

Except that that is Plastruct and not plastic Weld made by EMA which as already stated shows its composition is methylene dichloride.

again - it is Plastic Weld by Plastruct but I originally wanted help with application and not a Chemistry lesson

[BoD]

For fine work I use the Deluxe Pin Point applicator.  Quite expensive for what it is but does a great job.

[rab]

6 hours ago, Sheffield Midlands said:

again - it is Plastic Weld by Plastruct but I originally wanted help with application and not a Chemistry lesson

 

But this is RMWeb, where thread drift is inevitable

Edited January 9, 2020 by rab
Fat fingers syndrome

[TheQ]

32 minutes ago, rab said:

But this is RMWeb, where thread drift is inevitable

Can we stick it down so it doesn't drift ,  what  sort of  applicator would you use? 

[sharris]

48 minutes ago, TheQ said:

Can we stick it down so it doesn't drift ,  what  sort of  applicator would you use? 

A large hammer?

[dasatcopthorne]

On 08/01/2020 at 07:29, sulzer27jd said:

Apply the solvent to the sleeper and let it run under the chair. It doesn't require much pressure. I find using several gauges and a steady methodical approach of doing two or three chairs and then leap-frogging the last gauge over the nearest is a reasonable method. With wooden sleepers you can actually see the solvent getting drawn under by capiliary action. They generally require a couple of seconds more to get a solid bond.

 

John

 

Exactly how I have done hundreds.

 

Buy Butanone on ebay by the litre.

 

Dave

[Dave Hunt]

And methylene chloride is available on Eebygumbay for about nine quid a litre post free.

 

Dave

[Sheffield Midlands]

On 09/01/2020 at 15:34, dasatcopthorne said:

 

Exactly how I have done hundreds.

 

Buy Butanone on ebay by the litre.

 

Dave

 

14 hours ago, Dave Hunt said:

And methylene chloride is available on Eebygumbay for about nine quid a litre post free.

 

Dave

all good when you live in the UK - although I am british, I live in Canada. 

[dasatcopthorne]

On 11/01/2020 at 23:24, Sheffield Midlands said:

 

all good when you live in the UK - although I am british, I live in Canada. 

 

Also called Rubbing Alchohol.

 

Get the purest you can.

 

Any good??

 

Dave