Member postings for Jelly

Spotted this earlier whilst looking up something to do with the (now demolished) Longannet Power Station.

The keen eyed amongst you will notice that nestled away behind the gigantic shaper is nothing other than a heavily used Myford Tri-Leva, the oddest of the ML7 variants, accompanied by a late model Harrison M300.

That concludes today's episode of lathe-spotting with Jelly.

Drills on a MT shank are generally somewhat more rigid than an equivalent size drill in a chuck, in a non-production setting that usually translates to being able to drill bigger holes (which is great if you need to make something with a large hole in it as drilling is one of the fastest metal removal methods, compensating for boring being one of the slowest).

If you find yourself doing multiples or even whole batches of a specific part for a project, then you can purchase MT drills in smaller sizes which will allow you to both drill more aggressively and switch the drills in and out faster, which is a god-send if you have a lot of parts to make.

Is it possible that the clutch/brake assembly in the lathe is sticking after a long period of inactivity, which is causing the overload on startup?

Had that issue with my lathe when it first came to me and some manual jiggling of the clutch plates combined with an oil change actually cured it.

Not before I spent 6 hours painstakingly checking the wiring for a fault I was convinced had to be with the control gear mind you...

I'm not so sure about that, there are plenty out there which appear to have been used for production work doing small parts where the output didn't warrant investment in a small turret lathe like a Herbert №0 or №1.

I would guess most were kept alongside bigger lathes which were used more intensively, but they filled a niche commercially as well as being the model makers darling.

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This said, you do have to get a Super-7 with all the optional bells and whistles to have all the "proper" features for a fully equipped lathe, but most of that is quality of life stuff like feed trips, separate power feed, and a screw cutting gearbox, rather than missing functionality.

If you were trying to do it down, the biggest legitimate criticism is probably that it's mildly frustrating there's never been an option for a full screw cutting gearbox which can do both metric and imperial without switching change gears...

Am interested, have sent you a private message.

It's somewhat arcane full stop due to the sheer number of variations developed to cover the full variety of use cases.

That's the reason that industrial customers expect the likes of Sandvik-Comorant, Mitsubishi, Kennametal and Kyrocera to maintain significant technical sales departments and teams of demonstrators to support their customers if they want to retain their business.

Milling inserts seem to be especially bad as non-standard and proprietary inserts are much more common.

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This said, if you take care to purchase tooling which takes widely used and available inserts, it shouldn't work out expensive.

Especially if you get something for which generic inserts are available from the likes of APT, rather than being tied to a Branded supplier.

There's a level of efficiency saving that can be realised relative to established technologies by modifying the surface-chemistry at the electrodes to provide favourable conditions, an optimisation which is done in much the same way that catalysts for various industrial processes work.

ITM power (local to me), and several other electrolyser companies have had a great deal of success finding better electrochemical pathways to increase H2 production efficiency.

So in that regard, the video may be credible, and ChatGPT has given an overview of some of the optimisation strategies used in a sort of garbled, word-salad-y kind of way (as well as very confidently listing renewable energy, which is fundamentally wrong, as that doesn't reduce energy consumption just carbon emissions, exposing the language model's relative fallibility).​

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As to piezoelectric vibration, without reviewing the source material I don't find it particularly credible, but there's also some very interesting papers on out there on sonochemistry (initiating and controlling chemical reactions using sound) in niche scenarios which wouldn't make it entirely ridiculous.

It would be important to understand if they're accurately accounting for the mechanical energy provided by the ultrasound (and the efficiency of the sound generator) or not in their calculations.

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However, we all know that it is simply not possible to produce more energy from burning H2 and O2 than was expended in producing them in the first place.

If someone is showing an electrolyser which recieves 4kW of energy, but produces enough hydrogen and oxygen to produce 5kW of energy then:

• the most generous interpretation is that they're drawing the system boundaries incorrectly, and failing to account for another energy source, such as mechanical energy input or the chemical energy in a reagent or catalyst which is expended during the process and will eventually need to be replenished or regenerated.

• A much more likely one is that they're a charlatan and they know it.

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Their maths would probably be the deciding factor for me:

If they're claiming it is 15 times more efficient than a process which runs at an efficiency of 80-85% on an industrial scale (e.g. 15 * 85% = 1275% ), then they're exceeding unity and it's absolute tosh.

If they're trying to create an impressive headline number by using a deliberately weird way to calculate the multiplier, such as comparing their efficiency to existing approaches in terms of energy lost relative to a theoretical maximum (e.g. existing losses: 1kW * [1-0.85] = 0.15kw lost, our new process: 1kw * [1-0.99] = 0.01kw lost, and 0.15/0.01 = 15 thus our new process is 15 times more efficient)...

Then they're just being awful at science (and mathematical) communication, quite possibly on purpose to grab attention.

Edited By Jelly on 17/02/2023 16:43:03

It is likely that the manufacturer made provision for you to insert steel bars through holes in the base for use as a lifting point.

As shown here:

If there's no holes for that you can do the same thing by jacking the machine up and using a square/rectangular steel tube or C-channel but you have to drill it for the hold-down bolt hokes in the base of your lathe and bolt the tubes on for a secure lift.

As per other poster's experiences, I have found these generally worse than using a good quality carbon steel tap from a reputable brand (I use Tracey Tools carbon steel range for taps and dies I expect to use infrequently).

If you can flex your budget you won't regret it, substantially more capable than a Sieg (no offense to Sieg users, but that thing is really well designed and built).

I take it you have access to three-phase power, or the machine is single phase?

The original point being that it's important to know how the spindle is assembled and pick one with a angular contact bearings which are sufficiently preloaded...

That it looks similar to a British one is irrelevant, it's knowing the manufacturer chose to build the drill with a suitably rigid bearing arrangement.

Neither are widely available outside the UK (considering Andrei is in Romania) and certainly not typical of the kind of drill press you'd find if you were looking on a budget today.

I actually passed on loads of Progresses and Fobcos before I bought the Sealey because they were selling for a huge price premium (5× or more) compared to other similarly capable modern drills, precisely because they're built to a higher standard than the vast majority of new drills and can command a price point higher than many brand new ones.

So from the economic perspective, a Fobco Star on eBay today would cost £400-700, when there are regularly milling machines which sell for substantially less, which would be a better way to deploy the money.

Edited By Jelly on 12/02/2023 14:39:04

The Fobco is built very solidly, out of substantial castings, and uses a very rigid spindle design, which includes a pair of angular contact bearings preloaded against each other, which is not unlike the arrangements used in many modern "hobby" milling machines.

Compared to a more modern drill press, that definitely qualifies as being over-built (as in the design and materials of construction significantly exceed the minimum required to do an acceptable job).

My experience using Fobco drills is also that the fit and finish of the quill and the bore it slides in is also unusually high by modern standards, as is the inclusion of a quill lock of the highly rigid split casting type.

As such it is actually uniquely suitable to be re-engineered as a lightweight milling machine, in a way that very few drill presses actually are.

My big drill press is an early '90s Sealey with an MT3 spindle, and is far more capable as a drill than a Fobco star is, as well as seeming like a far more substantial machine...

But in reality it's internals have been heavily value-engineered to give maximum drilling for minimum money, so it would rapidly shake itself to bits if used for milling.

OP needs to be aware that not all drills are made equal, and if he wants to go down that route he needs to examine parts diagrams or sectional drawings to understand if the construction of the spindle is suited to conversion to milling.

Edited By Jelly on 11/02/2023 20:13:03

I ordered with Duct Store who were cheap, fast and good.

My setup is 80mm (nearest to 75 in spiral ducting), and works fine.

I would consider using an adapter as close as possible to the heater and running 100mm or 125mm as the pressure drop from the narrow ducting does seem to have an impact on the volume of air moved at lower power levels (although obviously bigger ducts does reduce flow velocity, so would reduce the "throw" of the supply valves).

It's worth noting that if you buy their push fit connectors with rubber seals on (very hand to not need to use sealant), the first few runs at full power will result in a really unpleasant synthetic rubber smell, which goes away, but appears to be years of low-level off-gassing accelerated into to a couple of hours.

My other suggestion would be to duct the air intake of the heater to draw air from floor level, to encourage mixing.

The current setup heats the room to a very comfortable temperature from waist height up, but doesn't have the oomph to push warm air down to floor level.

The alternative solution would be to use an in-line fan (probably a cheap mixed flow fan) to increase the velocity in the duct enough to reach floor level but it would take some careful setting of the speed controller to prevent it pulling too much air through the heater reducing it's effectiveness.

Also, worth knowing is that you can cut the hose barbs off the heater and pump fuel connections with a hacksaw, file the burr down and then use suitable brass compression fittings (5mm on the pump, 4mm on the heater) and microbore copper tube to run the fuel line.

I got those from BES.

Because I had ¼" microbore to hand I used 4mm/5mm compression to ⅛ BSP fittings joined to ¼" compression to ⅛ BSP fittings with a ⅛ BSP female × female pipe nipples; each assembly only cost a few quid and it's a lot more secure than plastic piping; I would expect you'd need to do that to make up the 4mm connector on the heater at least, which does allow you to use a 90° elbow fitting for neatness.

My fuel tank is outside and comes in via a ⅝" bulkhead fitting (with ¼" × ¼" compression connectors) attached to a metal plate which is screwed over a 32mm hole in the wall (to allow me to get a spanner in to access the compression fitting in the future if needed).

The pump and power supply are in a steel enclosure too for neatness and protection.

I can add pictures of my fuel and power setup later if you're interested, will just have to find them, though the ones I have are a bit messy as I took them before I replaced the stock wiring looms with a dedicated 7-core automotive cable and grouped all the wires at the heater end into one superseal connector...

Which is also a good upgrade as it turns out.

Edited By Jelly on 11/02/2023 18:37:03

Anything is possible right, and starting with a pretty over-built drill would obviously help... But it may not be easy or cost effective to get the performance desired.

If there's an MT spindle nose and the spindle is bored through (or can be) to accommodate a draw-bar then that gets over one of the two big issues.

You could probably even turn down and bore out a solid spindle with an external screwed or JT nose to fit an internal MT2/3 ISO20/30, or ER32 taper, provided it has enough "meat" to it.

There's also the consideration of how rigid the bearings are with respect to side-loading, most cheaper drills will use one thrust bearing at the bottom and one or more deep groove bearings further up, that will result in deflection during side loading and quickly destroy the bearings.

High-end drills sometimes use angular contact ball bearings instead which may be able to cope with milling forces depending on their arrangement in the spindle and pre-load forces.

Depending on the existing bearing seat sizes and how they're pre-loaded one could fit angular contact or taper roller bearings to improve a spindle for milling.

That leaves five issues left to to overcome:

• Rigidity of the body/table itself,
• The rigidity of the quill within the body,
• Precise z-axis adjustment,
• Secure locking of the quill to prevent z-axis creep, and
• Rigidity of mounting the x-y sub-table to the main drill table.

All solvable (for a given level of solved), but some more easily than others.

Edited By Jelly on 11/02/2023 16:47:12

Edited By Jelly on 11/02/2023 16:51:45

Ady1 mirrors my thoughts perfectly.

I will add that building a conventional milling machine from scratch is substantially more expensive than buying one of an equivalent level of rigidity.

I've helped two friends build custom CNC mills, and even discounting the electrical and control element it's a big undertaking.

For my sins I'm working up the plans for a Horizontal Boring Mill at the moment and even the steel for the frame to hold the (repurposed) bedways comes to more than a second hand bridgeport.

I mean that's not a problem, it's a project.

To me it's a very clear justification to learn to weld Alu and build a space-frame chassis for the existing build.

If you think the pay increases the nurses and other public sector workers have received in any year in the past decade are "above private sector" then you need to find a new employer.

At this point i'm even finding it easy to have sympathy with the junior doctors, after I realised my former employer pays office administrators almost what an FY1 doctor earns.

Edited By Jelly on 11/02/2023 10:04:36

PP Profiles (West Yorkshire) have alway been good for me, and free delivery with a 50 mile radius too.

I agree that providing a suitable cad file which is pretty much ready to go is the path to lower costs, although I always send a dimensioned drawing as well, to ensure they can spot any translation errors between the CAD file and the CAM output (a risk if you provide a CAD format their software doesn't open natively).

Excellent system, would not go back to Dickson/Aloris style toolholders.