Member postings for Jelly

The eagle has flown, (or being that it's from northern Sweden and extremely heavy, should that be "The walrus has left the beach".

Taken just before I packed it up to go...

Whilst certainly a breach of ParcelForce's conditions of carriage, this is not a meaningful breach of the ADR agreement as implemented by the Carriage of Dangerous Goods Regulations.

• In Table 3.2 of the 2021 ADR agreement, (available online on the UNECE website) there are two entries for Hydrochloric Acid (UN 1789) depending on the "packing group" a catagorisation which indicates the hazard posed and would be linked to concentration.
• For UN1789, PG II (the higher classification of hazard) column 3.4 indicates that the "limited quantity" is 1L (it's 5L for weaker Acid catagorised in PGIII).
• Under the limited quantity regulations, goods may be packaged in "inner packagings" of Plastics or Metal (or Glass/Stoneware where required for chemical compatiability with corrosive liquids) up to the volume specified in column 3.4 of table 3.2
• The inner packagings must then be securely packed into a secure "Outer Packaging" which protects the inner packagings from mechanical damage.
• So packaged, goods are effectively exempted from the requirements of the regulations, so long as the total quantity carried by any one transport unit is less than 8 tonnes, although each package or overpack should display the limited quantities diamond.

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You could report this to the VCA and HSE as the shared competent authority, (i think this would fall into the HSE's jurisdiction as it relates to the consignment of goods and labeling, not to the vehicles or transport operations).

But I doubt that they would really care about what is effectively a missing diamond on an otherwise compliant package, and one which would be meaningless to almost everyone other than technical specialists in the field of DG transport anyway...

Certainly it wouldn't be worth it using their resources to take enforcement action.

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All the major parcel operators including parcelforce are fully aware that customers routinely and flagrantly breach their conditions of carriage, with respect to liquids and dangerous goods.

Most larger parcel depots will collect several hundred kilogrammes each month of packages which have been identified as non-compliant, (often due to leaking) in dedicated bunded areas, which are subsequently sorted and identified for disposal/recycling by visiting chemists from a number of different specialist firms.

This has been the state of play for well over 15 years now, and it's well known to everyone involved, it's generally only when customers make really egregious breaches (such as sending dangerous goods which aren't packed in limited quantities, or which aren't eligible for that exemption, or cause a near miss where staff could have been harmed) that they will pursue fines or make a report to the competent authority, it simply wouldn't be practical any other way.

I'm just sorting out a box of suitable size and sturdiness to send it over to Andrew...

Will be most interested to see the results.

It's a particularly good demonstration of Perfect being the enemy of Good Enough...

Once something is sharp enough to cut [thing you want to cut] then any further effort is actually just wasteful... I don't need to shave with my handplane blade, and will never be called upon to slice sashimi with a wood chisel, so why would I behave like I do?

Unfortunately lots of people getting into woodworking as a hobby in later life do seem to get caught up on it and taken for a ride by aforementioned snake oil salesmen...

I have a concrete sectional garage with an asbestos roof...

I erected stud walls 3" deep, 1" in from the walls themselves, then put 75mm Acoustic Rockwool into the studwork followed by a vapour barrier over the top, and OSB to cap that.

the 1" air gap around the insulation is ventilated to ensure that any condensation on the walls is removed, and the vapour barrier keeps any internal moisture from getting to the cold surfaces.

I use a combination of trace heating and dehumidification to absolutely minimise the risk of rust, but in practice the temperature stablising effects of insulation would probably be OK on their own for this purpose.

From a thermal perspectve, having the air-gap which makes a major difference to the overall insulation of the wall design, without requiring additional material... When I did the calculations there's an optimal gap size before the space becomes becomes big enough that it's liable to convective heat transfer predominating, and the insulating properties drop off to less than a much thinner air-gap.

What's particularly awkward about that is that the optimal air-gap is determined in part by the temperature differential you want to maintain.

It was mixed in with with a big box of gun-drills I bought in an auction, so as far as I'm concerned it was free (the gun-drills were decidedly not free, but were still a very good price for what they are)...

It only gets used once in a blue moon anyways, so I'd be entirely happy to lend it on a "loan-er (lessor?) beware" basis if that assuages your nerves, as I am very curious to see what you can push it to do on your mill.

The inserts are about £15 a pack (of ten)

(I would also be shocked if you could actually cause real damage the main body without causing altogether more serious damage to your mill, especially as the inserts are held in by replaceable wedge-type cartridges and each pocket is supported by a good +20mm of steel.

That might be me... Sharpening woodwork tools, then grinding my own carving gouges, and then later shaping lathe/boring/slotter tools all felt entirely natural and easy.

That said, I suspect that I benefited from no-one telling me that as a mere mortal I wouldn't be able to do X, Y, or Z, and having examples of tools from my grandfather and great grandfather to show what good should look like, without really giving too much thought to how good they were themselves at the peak of their respective talents.

Ignorance can sometimes be a great gift, unfortunately it is very hard to apply wisely, judiciously, or even consciously.

I have a 160mm 10-insert, face-mill I would be happy to loan you for an experiment.

I'm not able to drive it at optimal settings with my mill's paltry 2kW, your mill with nearly double the power might have a small chance of doing so (in some materials).

Let me know if you're interested in having a crack.

I mean even a grinder is unnecessary, I know at least two skilled joiners who just use a fine garnet belt on a standard belt sander, held upturned in a workmate with a zip tie round the trigger...

"I need to do it about once a month for some minor damage or when the abuse chisel gets too worn, so why waste van or shed space on a grinder"

I have to agree, whilst you might sharpen woodworking tools every day or few days whilst using them frequently, if you're keeping on top of it, only a minute with a fine oilstone is required.

Wood turning tools and wood carving tools are different, and there's benefit to having a grinder to hand there (with a leather stropping/polishing wheel for carving tools), but they're also static workshop based activities which blunt their respective tools far faster than normal woodworking.

Nomex Thread arrived in the post, so cracked on with a little bit of (Flame Retardant) sewing...

I dislike being backlit when welding, and a mating my shield with a hood solves that pretty well, whilst also giving good protection when in vertical and overhead positions.

3M used to sell one designed specifically to work with this unit, but it's now ancient and officially obsolescent, so I just made one from a cheap nomex hood and some press studs.

Being PAPR, it's not actually hot or stuffy in there with the hood down, which is a nice touch.

I live alone (during the week at least) anyway so my own space isn't something I'm short on.

However, after cleaning my grandfather's house a number of times for him as he got less mobile, I realised that I was never going to smoke in a house I owned...

So the workshop, as a separate building became a place where I could do so in relative comfort, and I can confess to spending many a happy hour sat on my workbench smoking a beat-up falcon pipe and listening to late night R4/World Service programmes.

I have now quit smoking (despite the pipe, I'm still young enough that it makes complete sense to do so) and do find myself pausing rather less in the workshop... Although I did recently find myself spending 5 minutes dancing to some old-school 2-tone/ska music in there, mostly as a kind of celebration of clearing enough space that it was possible.

It's held at about 12C year round by trace heating, which is not warm, but enough that wearing coveralls or a jumper I'm at a comfortable temperature... Ice Climbing, all manner of Water Sports, and stints working in the North Sea have all adjusted my physiology to cope with the cold

Absolutely Jason, it's very much about picking your poison:

• If you reduce chip load then the inserts suffer increased wear and reduced life (although using sharper inserts with smaller tip radii will help mitigate this), and is particularly bad in alloy and stainless steels.
• If you reduce D.O.C. to maintain "optimal" chip load, you're maximising the potential damage if you do stall out the cutter, and you can run into similar problems as with chip load, but coming the other way (your D.O.C. is less than the tip/edge radius and results in uneven or excessive wear).
• If you reduce the width of the cutting path, then you lose the advantages you were looking for by using a big face mill in the first place.
• If you switch out the carbide face mill for a HSS shell mill, you can reduce the rotational speed (and thus the MRR) to bring the power requirements for "optimal" conditions down to something your machine can handle; but the whole job goes slower, because of the lower Material Removal Rate.

IME a combination of making compromises from the "perfect" conditions which are spread across multiple different areas will give the best overall results.

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I have lots of experience with larger mills and turret mills, but not much with the little "hobby" mills (I would call my Harrison a hobby mill, but it's got a lot more mass and "beans" than a Sieg so it's a matter of perspective), so it's hard for me to argue with Jason's suggestion that dropping chip load first is the optimal approach...

My personal experience is that face with lots of parts to do or a critical part to machine, if i don't have a "recipe" ready to go and need to fine tune, then I will usually do this empirically by a combination of sound (does the cut sound even), surface finish (am I getting tearing or vibration) and ammeter (is the motor drawing close to it's full load amps).

In that context Jason's approach offers a good starting point to work from.

Getting maximal productivity is less critical in hobby work than in a production or operational environment where time is always in short supply, but it's still satisfying, and sometimes necessary if you have ambitious projects.

Edited By Jelly on 01/12/2022 14:42:47

I'm on record as stating that the original Bridgeport isn't even the best Bridgeport Clone...

The variable speed head was a major jump forward, but still doesn't match the improvements that Czech, Chinese, Taiwanese, and Japanese made to the basic turret mill concept in terms of power, rigidity, and capacity.

A standard "J-Head" Bridgeport only has a ¾ hp motor, giving it less power than your SX2.7's 0.75kW. The later "2J2-Head" models with variable speed have a much more gutsy 2hp, and the difference is very much perceptible if you get a chance to run both types.

On a standard bridgeport even running a 50mm facemill at optimal speeds and feeds is pushing it, and requires the operator to hold back on DOC, or run at below optimal speed.

I think you're right that your job will be fine, if you heed Andrew's point... material removal rate (in m³/min or in³/min) is directly proportional to the power of a machine...

So for a given design of facemill insert, you can strike different balances between diameter and depth of cut but ultimately the relationship:

"Diameter × D.O.C × Feed Rate = Power × k (for some constant k)"

will always hold.

So if you choose to have an 80mm facemill, that will push you to compromise more on DOC or Feed Rate...

If you don't strike that compromise correctly and try to take too much in one go then you will stall the cutter, possibly damage inserts, and most likely damage your workpiece.

However, so long as you work with that constraint, it will function perfectly well, as my comedically large 160mm facemill has proved in the past.

Edited By Jelly on 30/11/2022 23:46:30

Depends what you're doing with it.

Mitsubishi's handy cutting power calculator suggests that to use the "optimal" feeds and speeds (430 rpm and 0.48mm per tooth), the SX2.7's 750w motor would be limit you to a depth of cut of 0.1mm per pass, taking a full width cut (in alloy steel)

if you reduce the feed to 0.1mm per tooth, you could increase the depth of cut to 0.5mm per pass, effectively sacrificing tool life for a (marginally) higher material removal rate.

Given that the calculators are generally a bit optimistic when it comes to hobby machine performance, it seems safe to say that you will be pushing it a little to use an 80mm cutter to best effect... But that it wouldn't be impossible to run one if you sacrifice depth of cut or feed rate, you just have to accept the limitations imposed on that tool by the motor's output.

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I have a 160mm face mill which I can run on my Harrison, and that tool is not used even remotely close to the limits of it's abilities...

But it's able to do exactly what you describe, and face a large part in a single pass giving a better overall surface, as long as I stay within the limits of what my machine can do... 50, 63 and 75mm cutters are all much more practical for most tasks, and can end up offering a higher material removal rate depending on the exact configurate of the job.

Actually the last three days, but helped a friend rip out their old central heating system, retrofit a double pipe system which is compatible with their existing combi boiler, but will be heat pump ready to future proof it, and commission the system...

Lots of crawling under suspended floors at ground level and general tomfoolery with lifting and laying floorboards, and the pièce de résistance...

Just as we got the whole system sorted, the only radiator they were retaining from the old system (a custom double angle bay window jobbie) burst open with a thumb sized hole as we brought the system back up to pressure turns out it was extremely badly corroded at a weld. Cue desperately draining the system and running around to find extra towels and buckets.

As of this morning, no leaks, and the house is the warmest it's ever been by some margin, even with the bay window radiator just capped off. Apparently modern type 22 rads are a hell of a lot more efficient.

According to NEPIC, the chemicals sector in the north East (from Morpeth to Middlesborough) employs 190,000 people directly, and there are 1,400 additional companies in the region (mostly engineering and engineering services) supported as part of the wider supply chain.

Regardless of whether Wilton itself has grown or shrunk (or is growing again), that's a lot of skilled jobs retained in an area which has otherwise haemorrhage opportunity for a good while.

FWIW I know of more than £100M of investment in scaling up of chemicals production on teesside which has happened in the last 12 months alone spread across 4 organisations, so the industry has a future there.

ICI Wilton and Billingham are still there, as are most of the jobs...

It's now "Wilton International" and whilst Billingham has merged into the wider "Seal Sands Complex" (The big obvious bit is now CF fertilisers) with the plants split between 20+ owners, which is it's own kind of stupid, coming from where it was but the North East is still going strong when it comes to chemicals...

How else do you think the North East manages to have the highest exports of any region of the UK, there's only so much demand for Nissan's and Black (or Red) and White Striped football shirts!

It was a consideration at the time but for precision purposes I want one which is calibrated to a known standard, so buying new covers that off...

I think I'm actually going to end up re-using the reground cast iron surface plate as a machine table in an upcoming project, in which case scraping it in would be excessive, especially considering I expect to have to do a fair bit of scraping on other parts...

Could not agree more!

I was looking to get my cast iron surface plate re-calibrated after some damage which meant it needed to be reground, and the chap quoting me said:

"I can sell you a newly calibrated Granite Surface Plate for less than the cost of me reworking your Cast Iron one. My suggestion is let me sell you a granite one, then when it comes back from the grinding shop drill some holes in the existing one for clamping accessories and you'll have a really excellent fixture table for welding!"

I think a 600x600 surface plate, Grade 1 would have set me back just over £200, which is not nothing, but is a lot less than the time, equipment and opportunity cost of trying to make (or remake in my case) such a precise surface.

Edited By Jelly on 23/11/2022 15:31:05