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1 hour ago, John57sharp said:

I may try and get a load in there and glue it square if warm water can soften it a bit?

The real things tended to bow outwards to a certain extent.

I have tried to replicate this on a few of my plastic bodied wagons such as this slope sided mineral by wedging the sides slightly apart with a cocktail slick and dunking it in very hot water for a few seconds.

Years later it is holding its shape, and I still haven't finished painting it! As far as I can recall, it was assembled with MEK.

I don't see why the technique wouldn't work in your circumstances.

RIMG1994.JPG.728d402a8f635d307760fa6a7a9b0d0c.JPGRIMG1992.JPG.eda70dabe1909af601fb3c41f14e95d4.JPG

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Injection moulded polystyrene can usually be re-shaped using the very hot water method Nick describes above.    Try that before exposing the model to more solvent !  Just need something to push it to a new shape within the body of the wagon.   It might need a few goes to reshape it enough. 

 

 

- Nigel

 

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A few lengths of cocktail stick and some very hot water later and...... Well it’s better. The sides needed doing again after the ends, but it’s passable now.

 

thanks for all the advice, I’ll get some of that lemon stuff before I do any more. Actually I might get some metals ones next for a change.

 

cheers

 

John

845919BB-EE17-4A64-9A07-64595A2BBBA5.jpeg

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14 hours ago, John57sharp said:

A few lengths of cocktail stick and some very hot water later and...... Well it’s better. The sides needed doing again after the ends, but it’s passable now.

 

thanks for all the advice, I’ll get some of that lemon stuff before I do any more. Actually I might get some metals ones next for a change.

 

cheers

 

John

845919BB-EE17-4A64-9A07-64595A2BBBA5.jpeg

 

Look for "d-limonene turpene" or "d-linomene citrus".  It's relatively innocuous stuff so is easily posted.



Mark

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  • 2 weeks later...

The worlds most frustrating tool to use EVER! Its taken me 1 1/2 hours to strip roughly 2/3rds of a teeny tiny engine body. The damn thing is so temperamental.

 

Anyone got any hints and tips on how to actually get these things to work?

 

Thanks

 

Julia.

20200124_194335.jpg

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I will answer my own question :P

 

I spent time today examining the airbrush gun thing to see how the thing works. In its original state it seems the thing is dependent on the air agitating the grit enough to flow through the long feed tube that runs up the middle of the hopper. The screw on the top is used as a basic needle valve to control the amount of media falling into the tube. As a result and the fact I didnt need a 'controlled' flow of grit but instead a good flow, I decided to chop it around a bit.

 

20200125_145038.jpg.46ba73b4ba5fe5c4ff0456c201ceb9b3.jpg

 

Firstly I turned up a Brass plug that was a press fit into the feed tube. I drilled it out to just under the size of the guns nozzle so that it will moderate the flow a bit and also help stop the nozzle getting blocked up.

 

20200125_145733.jpg.a8c6efe1da14b419898d30808fd0da12.jpg

 

I then chopped the feed tube as short as I dared then pressed the plug into the top.

 

On trying it out I now have full flow of grit through the guns nozzle, even to the extent of the grit flowing through the nozzle when no air is on. OK, the gun is no longer a controlled 'fine' flow but it now strips paint etc like its possessed! The gun is no longer reliant on the agitation to supply the grit but is now a gravity feed. The hopper now lasts for around 10 seconds of continuous use. I'm sure with some more mods it would be possible to even remove the hopper all together and just at a flexible pipe to a larger hopper.

 

I'm very happy with the results, and it means the tool is usable once again. Next is the cabinet for it....

 

Julia.

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37 minutes ago, -missy- said:

I'm very happy with the results, and it means the tool is usable once again. Next is the cabinet for it....

Julia.

 

Hi Julia,

I haven't used one of these myself, but a friend cleaned one of my models with his for my a couple of years ago, and the results were very impressive.

One thing to watch out for is that after cleaning, any steel parts will be more than usually susceptible to corrosion if you get them damp.

I have been toying with the idea of getting one myself, but so far haven't answered the question of where I'd find room for a cabinet.

 

After reading your post I found a video on YouTube of a guy reviewing a tool which looks remarkably similar to yours... and with similar frustrations.

In part 2 he makes a new nozzle, external grit hopper and cabinet. Maybe there are some ideas there worth pinching?

Part 1: https://youtu.be/fnK17v7Wbzs

Part 2: https://youtu.be/-dr1kp6tSOg

Nick.

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Thanks Nick.

When they are working they certainly clean things up plus they leave the surface keyed nicely for painting. I have experienced the corrosion in the past, it can even be triggered by fingerprints if not dealt with.

 

Regarding cabinets I have been looking at something like this as a starting point.

Linky thing to ebay perspex box

They guy in those videos seems to have a way more equipped workshop then I will ever have!

 

Julia :)

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Fantastic work Julia. The same person that blasted Nick's loco for him did an etched wagon for me a good few years ago with excellent results (I was also mighty relieved that the blasting didn't dislodge any of the strapping I'd carefully soldered onto the wagon!) 

 

There is a good article in MRJ134 about making your own blasting cabinet using a plastic crate from B&Q, a couple of plastic pots from Woolworths (remember them?!) and some heavy duty rubber gloves. I'll dig out my copy for you. I wonder if one of the Really Useful boxes might make a good basis - the way the lid clamps on seems like it could be useful. 

 

Andy

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1 hour ago, John57sharp said:

Can anybody decode the part 2-004 (7mm coach wheels for CCT) to the current part please? I’m just checking I have the correct axle length, which could also be an answer too, maybe easier to find?

 

cheers

 

john

 

The wheels that used to be listed as 2-004 are now 2-024 (7mm wheels on 12.25mm axles). Is it an etched chassis that you're building for the CCT?

 

Andy

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22 hours ago, 2mm Andy said:

Fantastic work Julia. The same person that blasted Nick's loco for him did an etched wagon for me a good few years ago with excellent results (I was also mighty relieved that the blasting didn't dislodge any of the strapping I'd carefully soldered onto the wagon!) 

 

There is a good article in MRJ134 about making your own blasting cabinet using a plastic crate from B&Q, a couple of plastic pots from Woolworths (remember them?!) and some heavy duty rubber gloves. I'll dig out my copy for you. I wonder if one of the Really Useful boxes might make a good basis - the way the lid clamps on seems like it could be useful. 

 

Andy

 

Didn't Edward do an article on grit blasting including a suitable cabinet in the 2mm Magazine years ago?

 

Simon

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4 hours ago, 2mm Andy said:

 

The wheels that used to be listed as 2-004 are now 2-024 (7mm wheels on 12.25mm axles). Is it an etched chassis that you're building for the CCT?

 

Andy

Thanks Andy, yes it’s the Association kit, I thought it was about done, but I’m having issues with the wheels not staying in the bearings, there isn’t much axle proud of the wheels.  I DO have the correct ones (thanks again) so I may need to get the bearings a little closer together, gently. 
 

cheers

John

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12 hours ago, 65179 said:

 

Didn't Edward do an article on grit blasting including a suitable cabinet in the 2mm Magazine years ago?

 

Simon

 

He did, and it's an excellent article (in the June 2003 issue if anyone wants to have a read - the magazine backnumbers are all on the 2mm website now in the member's area). He uses a professionally made cabinet which would be a good purchase if you had a dedicated workshop space, but I think Julia is looking for something smaller and more portable.

 

Edward did the abrasive blasting on Nick's L&Y radial tank loco (and my LNWR van).

 

Andy

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Maybe this could be useful if someone is looking for an affordable and small blasting cabinet:

https://www.hbm-machines.com/producten/straalcabines/straalcabinessub/hbm-sbc-90-straalcabine-zwart

Haven't found anything comparable on UK sites.

 

Website is in Dutch and it seems there is no option to change language. If in doubt please ask :-)

 

Jan

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On ‎25‎/‎01‎/‎2020 at 23:05, 2mm Andy said:

 

There is a good article in MRJ134 about making your own blasting cabinet using a plastic crate from B&Q, a couple of plastic pots from Woolworths (remember them?!) and some heavy duty rubber gloves. I'll dig out my copy for you. I wonder if one of the Really Useful boxes might make a good basis - the way the lid clamps on seems like it could be useful. 

 

 

A friend of mine, who is a very good 4mm scale modeller uses a thick-ish clear polythene bag as a grit control.  Either use hand in a glove inside bag, or hold model from outside of bag whilst working.    I'm still thinking about whether I'm completely happy about the fine dust control of this method, but he finds it effective. 

 

- Nigel

 

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Encouraged by Julia's 4mm-gauge diesel engine, I am planing to build a 5mm-gauge steam engine (see the drawing below).

 

The current overall reduction ratio is about 26:1 but, I would like to increase it as there is space for a larger than 30 teeth (O/D 6.4) idler and a smaller than 16 teeth (O/D 3.6mm) driving gears. Could anyone advise on how far I can go? There is enough room in the boiler to fit a 12 teeth driving gear and a 40 teeth idler to achieve a 47:1 overall reduction ratio. I am not sure if this would be practically possible though.

 

Another question is about the gear material; I am thinking of brass but Mikroantriebe can supply then in black polyacetal or white polyacetal. Apart from being less noisier than brass, is there any other advantage in using polyacetal (black or white)?

side-z.jpg

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  • 2 weeks later...
On 17/02/2020 at 10:29, John57sharp said:

CCT question. This is the etch I received (some time ago) can anybody identify the coach door handles or are these no longer on the etch and in which case any suggestions?

 

many thanks as ever

 

John

EEF7C99E-4367-4237-97CB-0CA1F502ED10.jpeg

 

Are you talking about the end door handles? There is one bottom right and three more to the bottom left.

 

The side door handrails are to be formed from brass wire or similar. There are bending jigs on the etch to make them the correct length.

 

Easier to see if you had the etch the right way up!

 

Chris

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Thanks Chris, it’s the side door handles I need, not the rails. and I think I had misremembered the reference to them being on the etch with spares, but that of course is the end ones. Its just a piece of scrap etch then I guess.


I did construct the vehicle the right way up!

cheers

John

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Is there a list (or obvious inference that can be made) for Grafar models which are compatible with the association conversion muffs? I'm thinking of restarting my 2mm efforts but I really do need to get a running steam loco under my belt and after a significant number of failed chassis builds, this would appear to be a good option to at least set me on the right foot (and make it possible to properly test my track!)

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3 hours ago, Lacathedrale said:

Is there a list (or obvious inference that can be made) for Grafar models which are compatible with the association conversion muffs? I'm thinking of restarting my 2mm efforts but I really do need to get a running steam loco under my belt and after a significant number of failed chassis builds, this would appear to be a good option to at least set me on the right foot (and make it possible to properly test my track!)

 

Looking at the Shop 3 listing on the website, the following are available as etches (bearings and conversion plain/geared muffs also needed);

 

2-320 LMS Jinty (latest design) - can also be used for the 4F but doesn't include the tender (these wheels can be converted using the wheel turning service).

2-318 GWR 64xx Pannier Tank

2-319 GWR Castle (doesn't include the tender, although the tender wheels can be converted using the wheel turning service)

 

I should declare an interest in the 64xx as I designed the etch for the rods/balance weights.

 

Also, Nigel Hunt has produced etches for the WD 2-8-0, the LMS Ivatt 2-6-0 and the LMS Fairburn 2-6-4t locos. All of these involve (a) Walshaert's valve gear and (b) pony trucks/bogies, so are a little more complex. They do include a simple tender chassis (apart from the Fairburn, obviously). Nigel has some threads on RMweb which cover the building of these locos, and Nick Mitchell has done a couple of articles on the WD 2-8-0 as well (in MRJ and the 2mm Magazine). Details of the etches are in the 'Small Suppliers' section of the 2mm website.

 

Andy

Edited by 2mm Andy
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Thank you Andy, that's very helpful - dredging through my old conversations with Shop3 / Steve D. I can see that thread of RTR LMS conversions - and given that I now I have multiple Jinty 'sets' laying around probably gives me good reason to get going on that, and gird my loins for a fourth chassis attempt :)

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Hi All,

For my first 2mm loco conversion I've started working on the Dapol 57xx conversion, as detailed by Pete King in the Feb/Mar 2016 Magazine. However, whereas that article described pressing normal drive bushes (3-112) into the original Dapol bearings, I am using the Dapol Pannier Conversion Bearings (3-225), which presumably are intended for this job and were introduced after that article was written.

I actually have 2 issues/questions:

 

1) I'm finding that the Conversion Bearings are a bit of a loose fit; they measure about 3.8mm, whereas the original Dapol bearings measure about 3.82mm. It's a tiny difference, but it means that some of the Conversion Bearings actually fall out the side of the chassis while I am handling it. (I haven't yet fitted any muffs, gears, wheels, etc. - I'm just having an initial look to see how the parts fit.)
Do you think I maybe need to knurl the outside of the bearing, or the inside of the chassis, so that the bearings are a tighter fit in the chassis?
Or won't it matter?

 

2) When I insert one of the gear muffs (3-102b) into the Conversion Bearing inner recesses, and measure across the outer faces of the bearings, I get about 8.22mm. In the article, it says that the distance across the bearing outer faces should be a maximum of 7.75mm to allow for a bit of side play. So it sounds like I need to shorten the muffs by about 0.47mm (from 6mm to 5.53mm). Does that sound right? Or do I need to shorten the muff a little more, so that the muff has a bit of side play within the bearings?

 

Hope someone can advise,

Thanks,
Ed

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