Member postings for Clive Brown 1

En58 is an !8/8 stainless steel. Being austenitic, it's not normally regarded as magnetic. Can be tough to machine, it work-hardens.

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Just over a year ago, I purchased a 3-axis DRO for my Warco 16B from eBay, (Fast-to-buy). Items arrived well packed and quickly. Total cost was ~£270.

So far the kit has worked as expected. The most taxing part of the exercise, apart from paying the money, is making up bespoke brackets to attach the scales. The pieces of aluminium angle suppled with each scale were of little use in my case.

I think that I'd use the same supplier again.

Edited By Clive Brown 1 on 27/09/2023 14:22:14

Why, many thousands of perfectly satisfactory model boilers have been made over many years in home workshops Their safety record is first class.

From the point of view of stress analysis, I see very little to be gained by a mathematical approach.Typical boilers have a lot of flat plate in their design, very difficult to model mathematically. Also copper, the most usual material, has in its highly annealled state an extremely low elastic limit and considerable plastic ductility.

I have a copy of the 21st edition. Used once in a blue moon. For my amateur modelling use, Zeus and the internet are entirely adequate. Having said that, it is fairly comprehensive but I certainly wouldn't replace it if it disappeared.

A small horizontal mill can be a useful tool for various model loco ops. Not as vesatile as a vertical mill, mine doesn't get used every day but it's well adapted for certain types of job such as fly-cutting smokebox saddles, chimney and dome bases etc as well as using small horizontal cutters and slitting saws. I'd miss mine.

Edited By Clive Brown 1 on 28/08/2023 15:54:44

My point was that a fairly high speed motor may not be the most suitable type for a small horizontal mill, which needs much lower speeds than a typical lathe. The speeds I use on my small "Zyto" are generally between 100 -200 rpm. This is from a 1400 rpm motor, so needing a 14:1 reduction ratio, with no built in back-gear. Mechanical speed reduction is quite cumbersome and electrical control can result in quite high torque loss, a fair bit is needed to drive a 3" or 4" dia cutter in steel. Using a 3000 rpm motor, as linked to in this thread, is even less attractive.

As well as considerably lower density than coal, charcoal generally lacks volatiles, and thus has a much shorter flame length. These factors will reduce its performance in a boiler designed for coal.

Edited By Clive Brown 1 on 28/08/2023 09:48:55

Whatever motor is finally selected, a horizontal mill, even a vey small one, needs low spindle speed and fairly high torque to do itself justice. Since sewing machine motors seem to have quite high rated speeds, I wonder if they're the ideal type?

Assuming that the diameter is 140mm, as per your earlier post, 2mm is quite thin. I'd go for steel, being a bit sturdier than brass, esp if it's softened by silver soldering.

Brass would be easier to shape though.

Edited By Clive Brown 1 on 24/08/2023 14:34:58

Pedant alert! although often used, the term "BSB" is incorrect, there isn't a BS for Brass Threads AFAIK.

My copy of Machinery's Handbook doesn't seem to mention Brass Thread, or Cycle Thread for that matter, but In 50+ years of model engineering I can't ever remember seeing Cycle Thread specified in a design, always Brass for 26 tpi.

4 thou should be OK IIRC, but thinner is probably better. Cleaning is important but Loctite 603 (hi-strength) is more tolerant. of poor cleaning according to the blurb.

40 tpi Whit Form is the basis of of a long established and widely available "Model Engineer", ( ME ) series which ranges from 1/8" to 1/2". Very useful for steam fittings etc. It's not Whitworth "fine".

0.2" dia. would not be in that ME series though. The rather rough etching of the size in the photo might suggest that these examples are specials.

Edited By Clive Brown 1 on 21/08/2023 18:48:04

I have a couple of boxes of needles, must be decades old. They are used in a couple of shop-made scribers that I have around the workshop. Last for ages, easily sharpened up, they're my "go to" tools. I'm lost if I mislay one.

Another needle forms the point in my lathe-tool height gauge. Couldn't do without them!

Why are all of the suggestions for a metric pitch? Presumably the ML10 has an 8tpi leadscrew, or am I mistaken? If it is imperial, then I'd suggest 16tpi. Simple gearing, exact, and the half-nuts can be engaged anywhere.

After all, the OP is using imperial sized stock.

I'd face this type job in a lathe every time, provided, in this case, the 4-jaw is 5" or over. The tiny facing concavity is of no consequence for this project, in fact, as intended it will ensure no rock in the finished job. A further benefit is that if the workpiece is accurately centred in the chuck then the centre hole can be drilled and tapped in the same op.

Edited By Clive Brown 1 on 03/08/2023 09:53:15

A backing pad fitted at the construction stage would be good, but too late now, but blind bushes are better still, presumably still doable.

IIRC, LBSC used to recommend even tapping handrail stanchions into the boiler barrel

That 14" blade in the picture will take some considerable power / torque to drive it through mild steel, let alone austenitic stainless.

I'd say 10:1 it's metric

Methods of balancing mentioned in this thread include drilling holes in, (how?), or gluing lead weights to the abrasive wheels wheels.

I would suggest that either method is highly inadvisable. The wheels would be locally stressed and/or the weights could become detached.