I've decided to start my next project which is to be a Stirling 8' Single. Early days yet but picture one is of the tender frames plus wheels.
Whilst waiting for materials to make up the stretchers to arrive, I decided to have a go at the driving wheels only to come across this hole. I pushed a bit of shim into it and it appears that it is 7/32" deep and heading toward the tread. I've notified the 2 1/2" Association, as that is where I bought the castings from, and I'm waiting to hear.
Jon
Hi Jon,
Is that one of the large wheel castings? I looked at mine the other day (as you will know) and thought they looked pretty good. The best solution is obviously to just get it exchanged by N25GA.
It is possible to 'bodge' blowholes with JB Weld but it's better not to have to. This involves gently warming the casting (heat the casting broadly, not just the holes) and then spreading/placing/poking/poring JBW into the hole(s). This is not particularly easy to do, especially on small holes and JBW goes through several stages of curing and is quite runny at one point, so larger holes will probably have a 'depression' in them once finally set that may need a top up. It can be machined but is still relatively soft - so for castings it's mostly about improving their cosmetics in my view.
However - whilst on the subject of JBW (for the Live Steamers here) there was a discussion recently on the ME Forum about repairing a cylinder and JBW was one of the solutions suggested. Apparently, there is now a high temperature version (HighHeat) of JBW that can be used where higher temperatures are involved (up to 450F & 500F for short periods) that may be useful for people here to know about.
So sorry to hear that Jon. Best to exchange it but there are alternatives fixes if necessary. Let us know how you get on.
Regards,
IanT
Ian
Thank you for the input, I'll see what happens with the Association before I go any further with the wheel. Tell me, what is JBW?
The new materials arrived today for the stretchers et al and so I made a return to the tender. I was pulling my hair out at one point as I have a set of frames from one quarter, a set of drawings from another and I'm trying to tone the whole thing down a bit as the drawings obviously have in mind a passenger hauling loco and tender. I managed to mess up one piece of brass that was to be a stretcher but sorted it out in the end. If it's fine tomorrow it'll be the garden but if rain the shed :)
Jon
Hi Jon,
I think Brian Kerens may be away skiiing at the moment but he'll get back to you as soon as he returns. There will be no problem supplying another casting to replace the faulty one.
John
Baggo
Thank you for letting me know, I'll await his return.
Jon
Members may be interested to know that Station Road Steam have a part-built model for sale at the moment. Here is the link: http://www.stationroadsteam.com/stock%20pages/7370/index.htm
I don't think it is bad for £250, what has been completed looks quite good.
Regards
Phil
Does anyone know which Model Engineer mags had Dick Allen's articles on how to build the tender for his Dee? I know it was 2012 but that is all. I could do with some pointers.
Jon
According to my index, you want volume 208 issues 4428 and 4429 (2012)
John
I've got these somewhere Jon...
Regards,
IanT
Baggo
Thank you for letting me know which were the correct issues. I've looked on Ebay and ME back issues but nothing there. Can anyone suggest any other sites?
Jon
Give me a day or two Jon (busy tomorrow) and I'll be in touch.
Regards,
IanT
Sent you an email Jon.
Regards,
IanT
As mentioned earlier, I'm thinking of using Slaters GBG3 motor and gearbox to power the Stirling more than anything, because it's there. What do others use to power their electric G3 locos?
Jon
There's a certain small blue Diesel (0-6-0) that's been seen at Ampthill occasionally Jon (and its pulled its owner around the Cheltenham track too) that has the motor horizontal in the body (it would be in the boiler in your case) that uses a simple vertical chain & sprocket (1:2/1:3?) drive to a right angle gearbox made from (angle grinder) spiral bevel gears...
Haven't checked their dimensions but these are £4.45 - many others available...
http://www.ebay.co.uk/bhp/angle-grinder-gear
I guess that any motor that will fit the boiler diameter will do the job - but need to look at its length with a single wheeler - however this seems a very robust arrangement and it clearly works well.
Dave W is the member to ask....
Regards,
IanT
On the drawings that I have for the Single, it suggests 1/16" stuff for the guard irons but these would scale at nearly 1 1/2" which sounds very thick to me. Does anyone know of an average thickness for guard irons? I would have thought 1/32" which is something near to 3/4" would do.
Jon
Ian
Ah, the inventive mind!
Jon
There's usually has to be some kind of trade-off between 'scale' and 'robust' and/or 'working' Jon.
If your model is going to be in a glass case on the mantelpiece, then 'fine-scale' is much more practical than if it might de-rail on someone's (less than perfect) track - not that we have such things in G3 of course! Also many things simply won't scale in the real world.
I've never thought too deeply about it and I'm sure that "fine-scale" means different things to different people but perhaps there are 'layers' to it?
The first is about simply ensuring that the general dimensions/proportions of the model are correctly scaled (e.g. scale height, width & length) and that the model simply looks "right". I'm sometimes surprised at how much some designers change or ignore these key dimensions for no apparent (good) reason.
The second is about the amount (and level) of detail involved - for example the brake fittings and cab detail. This has to be personal taste but sometimes you see models with one feature very well modelled and another completely omitted. I think the only rule here has to be to try to get the same level of detail throughout...
The third is that point where any 'scale' model just ceases to be 'usable' - in the sense that if it was an exact miniature replica of the original, many of the parts would either be too frail to function or just fail to work - a 'replica' model boiler being a good example.
To my mind, if you are going to build an engine from scratch, then you may as well try to get Level 1 right where possible. However, Level 2 is very much a matter of preference and how 'fragile' you want (or can risk) your model to be. Level 3 is not really a matter of choice, these are areas that must either be accepted or ignored - but which are also hopefully either not apparent (like the actual internals of the model boiler) or which can be disguised (dummy steam pipes etc).
So another long winded reply I'm afraid - but your question sits somewhere on the border between a Level 2 & 3 issue I think (the overall level of detail needed or wanted vs the practicality of using scale materials) and you are the only one who can really decide on what the right answer is for you.
The compromise generally adopted is to try and use the material nearest to the full-sized one provided it doesn't seriously impair the reliability of the model and on most published 2.5" designs, some slimming down is possible - framework being a good example. In G3 we need a certain level of robustness/strength but we do not need to factor in dragging hugely out of scale loads (e.g. giant drivers!) around...
:-)
Regards,
IanT