Member postings for Jelly

I don't personally think they're that much of a game changer for parting off on a Super 7 (or bigger), more of a nice to have.

The thing they can offer which is game changing on many smaller lathes (and even on big ones), is using an upside down threading tool to thread tight up to shoulders.

You can both reduce the size of thread relief needed to do so, and increase the speed of the lathe whilst being entirely confident you won't crash.

Loads of places, BS EN 10025-2 specifies hot rolled structural and engineering steels, so if you ask any stockholder for steel plate (or section) in grades S235JR through S500J0, or E295 through E390, you'll get hot-rolled material.

The standard also specifies that +N is post-fixed (e.g. S335JR+N) for steel which has been normalised which you could go for if you need to absolutely guarantee it to be free of stresses.

It usually comes black so you'd need to specify if you required it in a Pickled & Oiled or (my preference) Blanchard Ground state and pay for the additional processing if it's required.

Small Horizontal Mill is now [provisionally] claimed.

I wouldn't be too discouraged, there's a whole world of complexity when it comes to insertable tools, and selecting the correct insert for the job is a whole other skill-set to learn, generally inserts for Stainless are a different grade and chip-breaker design to those for normal steels.

They also often need high rotational speeds (even relative to brazed carbide) and the correct feed rate and depth of cut to work properly.

For example turning a 25mm steel bar:

• my preferred finishing inserts require 2500rpm to work properly but will take a cut as small as 0.1mm with a feed-rate of 0.12mm/revolution
• my roughing inserts will run at 1000 rpm, but need a depth of cut of at least 1mm (and up to 5mm!) and work best with a feed rate of 0.2-0.45mm/revolution

If I run either too slowly or with insufficient depth of cut, it will inevitably result in an awful surface finish.

​

I have a very similar lathe to yourself, and find that I get the best out of it with carbide inserts, but I had to spend quite some time:

• thinking about the kind of jobs I wanted to do,
• then doing research to work out exactly what inserts suited different tasks,
• then trying to work out what the best two or three inserts to buy would be to cover the whole range of things I wanted to do so I could get started without spending too much.

​If you want to learn a bit more about it all:

• Mitsubishi Carbide gives a really good explanation of the insert codes and toolholder codes, in their basic turning course, which is probably worth a read alongside your recent book purchases.
• Sandvik Coromant gives a good write up of selecting the right insert style for your job.
• Modern Machine Shop has a write up on picking the correct grade and coating of carbide

​​

Over time I have expanded my range of insert-holders and the inserts I keep in stock whenever a particular job called for something special and now have something in the range of 12 different grades of inserts, in 6 shapes and 4 sizes.

Most of which are only used for specific jobs, whilst there's four or five I use pretty much every time I turn the lathe on:

WNMG 080408 GM UM25A - Removing material as quickly as possible.

WNMG 080404 HQ CM20 Cermet - Finishing steel and stainless steel to the best possible finish, final pass when boring holes which need a good surface finish inside.

CCMT 120408 MPN PC25 - Removing metal quickly to form slender parts which would deflect under heavy cutting forces, boring most holes, roughing brass.

CCMT 060202 FP PC25 - Turning very slender parts or taking finishing cuts on small parts, very small boring jobs

CGMT 09T304 ALU AK10 - Finish turning and boring in brass.

Edited By Jelly on 21/03/2023 17:22:47

Pretty much as per the description, I'm struggling to clear much needed space in my workshop, and these items have been sat idle for years waiting for me to "get around to" using or selling them properly.

The following items are available on a Pay What You Want basis, I'd like to get something back for them, but I'm not going to quibble because mostly I'd just like to see them with someone who is going to use and enjoy them.

Ideally collected from just south of Sheffield, but I can probably deliver for fuel money in/around the M1 and A1 corridor anywhere between Nottingham and York.

Small Lathe:

It's the tiny geared-head lathe which is listed as (and pictured in the article of) "Unknown Lathes No. 93" on Lathes.co.uk

I've run it a couple of times over the years and it's actually very good to use despite one chipped gear tooth.

Originally came from the son of the man who built it (from a casting kit apparently, with a number of accessories (3 jaw, 4 jaw, faceplate) and some provenance information (including photos of some Loco's he built with it) which I'll include with it.

I'm a bit conflicted about parting with it as it really is a lovely item, and I have had half a mind to mount it on a wooden plinth and display it on my mantel-piece over the years, but that seemed like a step too far.

So it deserves to be cared for/used by someone rather than sat on my racking in "preservation".

​

Horizontal Mill:

A "Pallas Horizontal Milling Machine Model C" (Lathes.co.uk link, you'll have to scroll a bit) 

Bought from a print-works who had been using it with a grinding wheel and jig to true up the top of metal type.

It's been fully stripped and cleaned and repainted (apart from one casting which is primed but needs a top-coat); the short lived sojurn as a grinder does not appear to have done it any harm thankfully.

It's currently still disassembled, but all the parts are retained in trays including a choice of lever or screw-feed for both X and Y.

I did have a view to permanently setting it up for cutting gears, for which it would be an ideal machine, but just don't have the space to keep it really.

I'm not willing to offer it with the motor mount I bought it with as it was clearly dangerous, but fabricating something less finger-remove-y should be straightforward.

​

Hand/Flat-Belt Operated Pillar Drill:

Similar situation to the horizontal mill, has been disassembled, cleaned and primed for final painting but no space/time to re-assemble.

Has mechanical and hand down-feed by screw and two drilling speeds, as a drill it was an alright user that could maybe do with a new chuck/chuck jaws.

It strikes me that it would probably be a nice item for driving from a small steam/gas engine for demonstration purposes at rallies once painted.

​

Motors:

4 off single phase motors.

• 2 x 0.75 HP foot mounted,
• 1HP & 3 HP with lever operated clutch/break and anti-vibration mounts.

All running smoothly when last tested, but surplus to requirements.

Edited By Jelly on 21/03/2023 16:10:55

Edited By Jelly on 21/03/2023 16:11:55

Jokes aside, it's more like morph than you think!

You could apply for a US Patent* on that idea, call it something snappy like "Reverse Virtual Twinning", and hype it up to a bunch of VC investors for megabucks!

​

In principle the technology is there, and I've seen some implementations of "VR with Haptic Control" over the years in research settings which made it seem very do-able.

My friend who worked in the automotive sector had a colleague who left to start a business developing something like this to allow early stage "clay model" development of bodyshells in a VR environment and cut the cost and time involved in model-making, I think they're still going.

However, it's massively resource intensive (like a whole cluster of 40+ servers intensive) and very niche.

​

The Chem-Eng department at the University of Loughborough has "the Igloo" which is a VR training facility to allow students to better grasp the complexity of a real world process plant and "walk around" in virtual designs to understand how their design decisions have an impact on the real world operability of the plant, which is the closest thing I know of which is currently running.

Bangor Uni did have a VR suite with full haptic control in their Chemistry department for visualising and manipulating the structures of complex biological molecules like proteins, but they closed the department which is now in the process of being demolished.

​

*The US patent office has long-standing issues with granting patents which should be invalid due to prior art or obviousness and letting people sort it out by challenging the validity in the courts later; it's particularly bad in fields where software and the real world cross over with amazon recently getting a patent for remote controlled lighting, whilst describing something which building automation companies have been doing since the dawn of PLC's 40+ years ago.

Solid Edge will run in WINE by all accounts, although I can't account for how well it runs.

If your PC is beefy enough a Windows VM instance would allow you to run most CAD programmes, but it will be extra resource intensive.

You could also install a windows instance on an AWS server, and RDP into that (although AWS is chargable over a certain usage level, albeit it's something like $0.20 per hour)

There's also Dual-Boot, which would be my choice in your shoes.

I believe what you're getting at is that I committed that cardinal sin (for which I always curse clients) vagueness of specifications!

I often find myself stuck between two mindsets:

• A poor student/young professional trying to do things for myself on the cheap which is firmly established from my younger years, and
• The one I have at work, where if it's required to tool up an additional workshop space, or to get stuff out the door on time, I wouldn't even have to think before raising a PO for £900 of Dormer or Guhring taps from Eriks, whilst the cost would just be noise on the P&L account of a project running well into 8 figures.

So using "decent" as a shorthand for me was very much "of an adequate standard for semi-frequent use in a commercial environment, such as a maintainence fitter might keep in their van/room/toolchest".

​

In my head I had effectively settled on wanting something firmly mid-range covering the sizes I regularly encounter in repair/automotive use where having them to hand is time-critical and I can't just order what I need and wait three days with a mate's car in bits in my yard/their drive.

(side note: it would be my advice never to let someone who owns a "modern classic" know you have any mechanical aptitude unless you're really good friends).

​

If I have a planned task to do which warrants professional tooling (20:1 ratio 16mm gun-drill jumps to mind), or it will make my life better (CBN turning inserts, Metal-Core welding wire) I don't flinch at buying exactly what I need, but there has to be a clear justification (or very cheap auction lot) to do that.

On reflection I ended up going for the Sherwood set from Zoro, it covers the exact range I want to have on-hand, and ultimately the price and portablity of a shadow-foam case swung it for me.

I will probably buy singles of some sizes of spiral flute taps in due course as and when I have projects which require large numbers of tapped holes.

When I actually thought about why I had stuck with dodgy metric sets (when most of my tapping is metric) it was because I kept not having taps to hand whilst working away from the workshop and having to buy cheap sets from the nearest trade counter to get the job done, which then land at home and justify not fleshing out a decent set of core sizes, which leads to breakages and further perpetuates a cycle of emergency purchases.

Yeah it's a generic diagram lifted from my old uni notes, which dealt with boiler design in a sort of fuel-agnostic way.

In practice I have seen both gas-fired power boilers and thermal oxideisers (with heat recovery) which use a comparable construction, usually because they're fuelled by an off-gas or vapour stream which is readily available but would be unsuitable for a gas turbine due to composition/contamination.

The challenge of available space to maintain sufficient film thickness is obviously a problem with scaling which is difficult to overcome when modelling.

I know myself well enough to admit that there's no chance of any good intentions to make a box translating into me doing so in a timely manner...

If I go down the singles route then the preferred option is popping them in one of my bisley cabinets with bubble wrap lining the drawer to protect from damage, which is how all my imperial and UN[X] taps and dies are stored.

Well now you've given me a conundrum...

I had all but forgotten about the existence of Drill Service despite them getting me out of a bind with weird size/form factor drills available next-day multi times, and buying one spiral tap is about the same price as a set of three hand taps (cheaper in larger sizes), so that would be a good option if I bought singles.

On the other hand that Sherwood set Bill pointed out is pretty much bang on the sizes I commonly use, and a very attractive price-point.

Can anyone point me at a supplier which offers a decent quality (metric) tap and die set in HSS, for a reasonable (for the quality) price?

Looked at the usual suspects (Arc, Chronos, RDG) but they all include those dubious pot-metal diestocks and tap wrenches which I've come to associate with iffy quality (apart from Chronos who appear to have nicer sets but only in Carbon steel)

Cutwel offer a very complete presto set M3-M24 fine and coarse, which is actually reasonably priced for what you get, but it's got a lot of stuff I'm unlikely to use in it, so not worth the (significant) expense.

I have priced up buying a full M3-M16 coarse set from Tracy Tool as singles, and they're pretty competitive, but it would be nice to be able to get a decent set which is easy to keep organised.

Edited By Jelly on 20/03/2023 22:25:53

Whilst I see what you're getting at, as the statement sort-of holds for the temperatures in a model boiler of an existing conventional design..

It's not strictly true and ignoring the consequences of that statement only being true within certain conditions (bounds if you will) kind of obfuscates the fundamental thermo-fluids of how you overcome the limitation for people less familiar with the topic at hand.

Most triatomic (Carbon Dioxide, Water, etc.) gasses do have an emissivity profile which results in IR (radiative heat) emission above a given temperature, even though they're not luminous (i.e. don't emit in the visible spectrum).

The rub is that this emission occurs when the gas is held uniformly at higher temperatures, so any boiler design which allows for rapid cooling of the flue-gasses will not allow the radiative heat transfer to predominate and thus effectively wastes that heat transfer opportunity forcing the boiler to rely on conduction and convection.

The result is that a very different boiler design is required, to take the example of the supercritical steam generator design which is typical of modern power-boilers (as opposed to heating boilers) the basic design is always a water-tube or finned heat exchanger.

An example of a typical arrangement is shown in the below figure, and you can see that the design is optimised to give maximal residence time at high temperature for the flue-gasses to emit radiatively, before any convective/conductive heat transfer begins, and the heating of "streams" of working fluid occurs in the order which to maximises overall heat transfer, rather than a convenient co-current or counter-current flow relative to the flue gasses.

Crucially whether it's a water-tube/finned power-boiler or fire-tube heating-boiler (akin to oil-fired marine boilers), the upshot of not having luminous char from a fuel source to help maintain radiative heat-transfer in non-ideal geometries/conditions, is requiring much greater consideration of overall path length, and ensuring the tubes and furnace are sized correctly at each point in that path to achieve the most efficient heat transfer from the flue gas.

Which of course is a completely different way of thinking about boiler design to traditional locomotive designs, which will feel alien to a lot of people who are used to a conventional locomotive "once-through" design...

Although perhaps less so for people who have faithfully reproduced more modern loco boilers which used unequally sized tubes getting larger as they go higher in the boiler for similar reasons, as engineers learned to optimise the combustion of the volatile component of solid fuels.

Edited By Jelly on 20/03/2023 17:20:43

[Kind of] finished fitting the Tool Library for the Lathe in my lunch hour, switching to using 80mm M6 bolts with penny washers and T-Nuts (the spiky woodworking type) has mostly solved my misalignment problems

Although I could only get 30 of the required 32 T-Nuts today, and one hole needs to be widened slightly and the bolt refitted.

To say it was a nightmare to put up would be an understatement, but now it's done it's clearly an improvement.

Whilst the three brackets holding it are up to the job, definitely thinking some additional bracing wouldn't go amiss, 16 Multifix C holders is not an insubstantial amount of weight so it bounces a little currently.

Edited By Jelly on 20/03/2023 15:00:17

I am mystified too, I even went to look at the primary legislation and it's clear that all model trains/traction engines, would be out of scope of the gas regulations and treated the same as other boilers.

There's some complications with steam-plant type model boilers, but nothing that can't be worked around with basic awareness.

.

One wonders if it like the situation with welded and non-copper boilers, where they're already permitted but actually finding someone within the model engineering community who would test one under those rules is hard causing them to be viewed with suspicion and generate misconceptions.

.

As JasonB points out you can already do pretty much whatever you want as long as it's safe, if you're willing to submit to a true independent inspection against the relevant regulations, (and crucially pay that inspector).

.

To Hoppers about Aus, in the UK we have some of the most non-restrictive [whilst still existent] safety regulations in the world, but it does put the onus on you to prove that whatever you decided to do is in fact safe, which is often a complication as it takes resources and documentation.

(The UK approach should be contrasted with only being allowed to do prescribed things which the government has decided will be safe).

Finally got round to doing something I've been meaning to for ages, and made a holder for all my toolholders.

Did a test fit on the floor, because mounting it is going to be a right arse, and glad I did, the studs in 4 of the positions are either marginally too close or marginally too far apart, so I will need to remove them and file the holes out slightly then refit using gorilla glue.

That might be a tomorrow job though, nothing about threading M8 studs into 6mm holes in 19mm ply thirty two times in a row was particularly fun...

Well that's would certainly be one way to force people to move on from copper!

(For those not aware, copper is particularly susceptible to hydrogen embrittlement due to alloying non metals in most grades, a particular grade of pure deoxidised copper is suitable but still doesn't perform all that well. Much experimentation is ongoing as to just how much H2 can be blended with Methane before it becomes problematic, with a view to altering the composition of mains gas.)

I would think that designing a burner to match the required thermal input of a boiler would be easy enough, anyone who can make an injector can make a Venturi burner.

The interesting bit is the relative controllability of gas boilers lending itself to water tube and finned heat exchanger boiler designs with much higher thermal efficiency and more responsive control characteristics, something which is restricted to blown pulverised fuel boilers when working with solid fuel.

There's also oil-firing which has many of the advantages of gas without the need to store the fuel under pressure, the Doble Steam Car used an oil fired water tube steam generator to propel a 2 ton vehicle to 110mph in 1909!