Noted. Stuart models name may well be very old but present owners are not.

Stuart Models has been owned by Bridport Foundry for about 8 or ten years. Apart from old stock, they make their own castings so IF there's a problem just send back and it will be replaced.. If you have the misfortune to spoil a casting spare ones are available, and their in the UK.

I dealt with Forest Classics recently, sent the right part, quick, and very helpful. Noel

Friend of mine recently completed a Stuart 10V and has just received the castings for Victoria, he had no problems with the 10V castings and the Victoria ones look very nice, these are from Bridport Foundry. The Victoria ones look so nice I was almost tempted away from loco building, only just managed to resist!

There was a time a few years ago when Stuart castings seemed to be very variable in quality, but since the change of ownership have much improved.

I built the R&B gas engine from Polly castings and both the castings and service was excellent.

Good luck with your choice, hope you enjoy the build

Dave

I must admit I've not actually used it very often, yet!

The 'Worden" type T&C grinder is for lathe tools, and for the end- but not flute- edges, of end-mills and slot-mills. Sharpening flutes needs a more sophisticated machine with tool-axis centres and helix-follower.

It holds the lathe tools in a simple block with channels allowing the side and front clearance to be cut. It might grind the top-rake, but not easily due to access too the wheel. If you use tangent-tooling, which I have never tried, a T&C grinder would seem the better sharpener than a bench-grinder.

The T&C grinder is not for hogging great lumps of steel off an HSS blank. To minimise wheel wear, remove the bulk of the metal with a bench-grinder, use the T&C machine for finishing the surfaces to the accurate angle.

For grinding an HSS blank to a particular shape recently, I cut the bulk away with an angle-grinder fitted with cutting-disc! Then a bench-grinder – actually to finished size as the tool was not critical, simply for undercutting the shoulder end of a spigot to be threaded with the form ground on the other end of the same blank..

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For grinding HSS lathe-tools you don't need a full T&C grinder unless working to critical angles, such as cutting threads. The clearance and rake angles are not too important for most materials, within a degree or so is usually near enough; but the edge sharpness is the important bit. The clearance has to go right to that edge.

One tool that does demand care is a parting-blade, for if its end is rounded or not at right-angles to the flanks (in plan) it can cause all sort of grief by trying to cut a chip wider than the kerf.An old error, and one that I took years to discover, is to grind a parting-tool at an angle to minimise the pip or burr left on the work-piece.

An insert-type parting-tool has a little V-groove along its top, tending to fold the chip inwards, but that would be impossible to give to a steel blade without a specially-designed grinder.

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For an ordinary bench-grinder, a simple table with an adjustable fence you can set to specific angles, would greatly improve it for tool sharpening. The table and fence can be made to be set with angle gauges easily cut from thin plate. For plain turning, free-hand grinding the tool to a template or adjustable-square will often suffice, especially if you then carefully hone the edge to a good finish with a fine stone.

Harold Hall's Tool & Cutter Grinding, in Special Interest Publishing's "Workshop Practice" series, deals comprehensively with this topic, to the extent of offering designs for tool-rests that effectively make a bench grinder into a simple T&C grinder.

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You often see that remark about HSS tools being "better" for low speeds. The machine's torque is only relevant for depth of cut (DOC), and all lathes have their limits for either HSS or carbide tools. A carbide insert can be worked at higher speeds than steel for the same material, but that is not the same as having to be. I have not found it a problem using carbide tooling at quite modest speeds on either my Myford ML7 or the heftier Harrison L5, for similar work diameter and material. (I often have the latter lathe ambling round at under 200rpm, as I estimate, with the 3ph motor still at a healthy 900 – 1000 rpm.)

It is usually easier to obtain a good finish with HSS if only because the insert tool is really designed for fairly specific materials and conditions, and seems to cut in a rather different way to a steel tool. This is particularly so if you find yourself trying to work some awkward stuff rather than good-quality free-cutting steel, and may need experiment a bit with tool geometry. HSS is also a lot cheaper!

I use both, but the HSS probably more than the ceramic-insert tooling.

My recent experience of Reeves castings are that they can be variable in quality, some cast iron ones that I have machined have areas that are so chilled and as such it’s like trying to machine glass, the gunmetal/bronze castings that I have tackled some have very hard outer skins which need cobalt drills to penetrate and inside the castings are voids some encroaching into finished areas. We have to realise that the casting process can have variable results depending on the foundry practices used by individual foundries and its never easy to produce very small castings consistently because of their size and the rapid rate at which they can cool being the source of problems. Model Engineering castings by virtue of their size could always be problematic and we have to accept there may be problems. Dave W

If you can't machine the surface to remove all the casting texture would be when it needs replacement if one is available. Also if there are faults in critical surfaces that show up as the casting is being machined then you could reasonably expect a replacement. Thin section castings can suffer from "chill" which is hardening when allowed to cool too fast and that makes them hard to machine, as they are small you can often heat treat them yourself but again could be grounds for a replacement or time to get out the carbide tooling.

Poor positioning of features such as bosses where hold down bolts may go is something you generally would have to work around as that is likely to be caused by the pattern and a replacement is likely to be no better

I think all of Chiltern's offerings are ready machined

When I used the term “over size” I meant there was more than 0.020” on each surface to be machined. As said, this is to remove the hard skin. This is good.

Conversely, “under size” meant casting was already below drawing dimensions. Then you would have to use something like an epoxy resin to build it up to size. If the casting is gun metal a little piece of bronze, silver soldered in the right place, can rescue the casting. This is not so good.

Castings are fun!/?

JA