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ptjw7uk
05-05-2013, 05:56 AM
I think my brain has been metricated!
Got job to do on some 25mm square stock, could do it in the 4 jaw but always hankered for a keats fixture. So purchased one from a UK store.
Fitted the stock ok but with only 2 threads biting on the bolts thought I should get some longer bolts.
Drag out the thread gauges and mic, strange size 9.3 mm dia and 1.6mm pitch.
So tried online searches, nothing obvious showing up nearest was a 9mm 1.5, a bit on the small side. Had a look in the shop and found a bolt that fitted, then the penny dropped!!
Its not metric at all just good old 3/8 whit.
Looked for some longer bolts and found some studding, cut to length, jobs a good un!
So I really must stop thinking that everything new must be metric.

Peter

MrFluffy
05-05-2013, 06:22 AM
You've just got to remember that keats block may well have been designed or built by one of the older less metric friendly businesses :)
I prefer metric, but I still have a set of imperial collets and spanners and allen keys etc, since it keeps popping up in the uk as a throwback legacy.

Now off to source some 50.8mm bore grinding wheels for my surface grinder, at least thats metric and not in some imperial units :D

John Stevenson
05-05-2013, 06:40 AM
Those Keats plates if I think are the same as what I'm thinking of are made in India, home of the Raj and firmly ensconced in the old Imperial threads of the Empire [ bugle call and roll down the flag]

It was a well known saying that the sun never set on the British Empire which was meant to say that the empire was so widespread it was always daylight somewhere.
When in truth it was because God would not trust an Englishman in the dark. :o

ptjw7uk
05-05-2013, 06:51 AM
Your probable right John, made in India but I just couldn't have bought the material for the cost of the Keats.
Luckily I still have all the whit taps and dies to hand, you never know!!!
Mind you even 0ba is metric!
Peter

J Tiers
05-05-2013, 12:23 PM
You've just got to remember that keats block may well have been designed or built by one of the older less metric friendly businesses

Nonsense.....

EVERYONE in the UK is 100% only metric!

At least that is what we are told when the subject of metric comes up................................................

wierdscience
05-05-2013, 01:11 PM
I've decided to start manufacturing an export product in all metric dimensions and threads.
I think I'll use 8x1.5 10x1.75 and 12x2.0 threads that way it will be all metric and people will be happy.

Jaakko Fagerlund
05-05-2013, 01:54 PM
I've decided to start manufacturing an export product in all metric dimensions and threads.
I think I'll use 8x1.5 10x1.75 and 12x2.0 threads that way it will be all metric and people will be happy.
Thinking of OEM lockout? :)

Forrest Addy
05-05-2013, 02:45 PM
I never tire of repeating at every opportunity: The metric system is designed for people who can't divide by two.

rohart
05-05-2013, 03:31 PM
Forest - if we'd developed with six finders on each hand, the world would have been a better place, I agree. Twelve is a much better choice of number system than ten. But, the idiots that invented counting used their fingers, and so we're stuck with base ten.

Given that, the metric system fits in with our counting system very well. And if you want to go up in factors of 2, you just have to adjust, and go up by 2, 2.5 and then 2 again, and repeat. Aesthetically, you can use the odd set to your advantage, and if one thing is 16 times the size of another thing, nobody can tell it's a power of two anyway.

All that's needed is a name for the length that is a tenth of a millimetre - 4 thou - and for architects to start using metres instead of millimetres. I really can't envisage a room that measures 7520 x 8740 - I'd much rather be told it's 7.5 by 8.7 metres.

I suppose it comes down to the old rivalry between Britain and France. We won the meridian battle, so they got sore and sold metric all over Europe. If you lot across the pond had developed your technology a little earlier, instead of running around fighting each other, metric might not have got the foothold it wanted.

lazlo
05-05-2013, 04:09 PM
Your probable right John, made in India but I just couldn't have bought the material for the cost of the Keats.

The Keats block is a neat idea, but you could make one with a weldment in less than an hour, depending on how anal you were with the finish.

Stern
05-05-2013, 04:15 PM
OK, please dont shoot me, but can someone tell me what a Keats block is ? I did try to google it and got this

http://news.google.com/newspapers?nid=1322&dat=18871221&id=VkERAAAAIBAJ&sjid=PJsDAAAAIBAJ&pg=5344,3354174

which after looking over for about 20 min realized I wasnt going to find what I was looking for lol

lazlo
05-05-2013, 04:26 PM
http://i164.photobucket.com/albums/u15/rtgeorge_album/keats_zps7b47292b.jpg (http://s164.photobucket.com/user/rtgeorge_album/media/keats_zps7b47292b.jpg.html)

Forrest Addy
05-05-2013, 04:29 PM
Richard: I was poking fun at the Metri-dweebs. One of my Metri-phile friends describe the Imperial System of weights and measures as the "Imbecile system". Competing ideas evolve into tolerance and better understanding with a little humor.

rohart
05-05-2013, 04:45 PM
I didn't take your post as a full frontal attack - but it inspired some thoughts, and there you go.

One the subject of the Keats fixture, I googled and came up with a page of Ron Chernich's where he goes into several ways of holding work eccentric to the spindle axis.

I found it entertaining.

http://modelenginenews.org/techniques/crankshafts.html

I prefer large angle plates, with lots of bolts and screws. And some balance weights too.

The Artful Bodger
05-05-2013, 04:53 PM
That is not really a Keats block and has only half the functionality of the genuine ones which can be used, for example, to hold round stock horizontally on a machine table. The makers are Exe Engineering of Exeter http://www.exeengineering.co.uk/home.cfm they do not mention the Keats block on their site but the one I have clearly carries their name.

You can see mine behind the chuck..

http://farm9.staticflickr.com/8553/8710914817_6548b9ec3a.jpg (http://www.flickr.com/photos/58195047@N04/8710914817/)
keats block (http://www.flickr.com/photos/58195047@N04/8710914817/) by xxxxxx (http://www.flickr.com/people/58195047@N04/), on Flickr

Stern
05-05-2013, 04:54 PM
OK, thats for clearing that up :) learned something new again :)

lazlo
05-05-2013, 07:09 PM
That is not really a Keats block and has only half the functionality of the genuine ones

That's interesting AB. The "Keats" block I posted is made by College Engineering, and has a long-standing tradition with Model Engineer/Model Engineering Workshop, going back at last 50 years.
http://www.collegeengineering.co.uk/KeatsAngles.htm

I'm not sure I see the disadvantage of the College Engineering version? They both hold round or square stock on a lathe faceplate? In the picture I posted, the movable "jaw" is on backward.

whateg01
05-05-2013, 08:03 PM
This thread reminds me a bit of the conversion to metric of all of the automotive stuff. Looking for aftermarket wheels for a car a few years ago and I couldn't find new wheels that would fit my car. Gone were bolt circles of 5x4-1/2". Now we have 5x114.3mm. Took me a bit to realize that, but once I did, the world made sense again.

Dave

The Artful Bodger
05-05-2013, 08:17 PM
The difference is Lazlo that the Exe Engineering version has two datum surfaces so work can be held perpendicular to the surface (as on a lathe face plate) or parallel to the surface as on a milling table. Someone told me that Exe Engineering that the intellectual property rights over the original design.

Here is an original Keats advertisement

http://farm9.staticflickr.com/8411/8712611042_eb525c4a75.jpg (http://www.flickr.com/photos/58195047@N04/8712611042/)
Keats add (http://www.flickr.com/photos/58195047@N04/8712611042/) by xxxx (http://www.flickr.com/people/58195047@N04/), on Flickr
..showing one the same pattern as the Exe Engineering ones.

The movable jaw can be flipped over to hold large or small stock.

Weston Bye
05-05-2013, 08:24 PM
I am in somewhat of a quandary here. Doing an article where I will be making details to bolt onto a machine made with metric fasteners and obvious round number metric dimensions. (bolt spacing & such). The same machine has hand wheels calibrated in inch. The metal stock for the bolt-on details will be mostly full dimension inch material. The fasteners not attached to the original machine are already specified inch.

What a mish-mash to dimension.

TGTool
05-05-2013, 10:28 PM
In the picture I posted, the movable "jaw" is on backward.

There's a backwards? I always presumed it was made to go on either way depending on the size of the stock it was holding.

The picture of the ad for the Keats block is certainly interesting. I see the prospect of vertical or horizontal mounting. OTOH, there are several small design features that seem problematic. The clamp now requires that U-bolt arrangement. There's a through hole for long stock but the hole doesn't seem to line up with the V-block unless the illustrator they hired to draw it only half understood what he was being told. The blind end of the V-block presents some manufacturing problems - not insurmountable, but then not as easily machined as the more recent incarnation.

lazlo
05-05-2013, 10:42 PM
The difference is Lazlo that the Exe Engineering version has two datum surfaces so work can be held perpendicular to the surface (as on a lathe face plate) or parallel to the surface as on a milling table.

The movable jaw can be flipped over to hold large or small stock.

Ah, very interesting! So couldn't you do the same setups with a V-block bolted onto a shop-made baseplate? You'd have to have tapped holes in the side of the V-block, but a lot of them do, or you could tap a cast iron V-Block?

Paul Alciatore
05-05-2013, 11:05 PM
Forest - if we'd developed with six finders on each hand, the world would have been a better place, I agree. ...<snip>...

Just be glad we do not have one hand with seven fingers. Can you imagine: 7, 49, 343, 2401, 16807, ... I will take 2, 8, 10, 12, 16, or even 20 over that.

TGTool
05-05-2013, 11:33 PM
I had a foreman at one time with a sense of humor. He came around one evening with a string around one finger and said, "You know what that is?"

I didn't.

"That's a Polish hand calculator - with memory. If I have to, it can count up to twenty-one." :)

Paul Alciatore
05-05-2013, 11:50 PM
Weston,

Apparently you are not alone in this. I am replacing the operational handles and grips on the drill press I recently purchased and found that the factory items are a complete assortment of English and metric designs. One may be 3/8-16 and the next M8 or M10. You can not take anything for granted.

http://bbs.homeshopmachinist.net/threads/58970-Tool-Gloat-New-20-Inch-Drill-Press?highlight=drill+press

The Chinese have no hesitation in mixing dimensions. As to exactly how acceptable this is, I can not say. I have made things for my own use that mixed dimensions and found that they do work. I hate it more when someone mixes slotted and Phillips head screws on something.




I am in somewhat of a quandary here. Doing an article where I will be making details to bolt onto a machine made with metric fasteners and obvious round number metric dimensions. (bolt spacing & such). The same machine has hand wheels calibrated in inch. The metal stock for the bolt-on details will be mostly full dimension inch material. The fasteners not attached to the original machine are already specified inch.

What a mish-mash to dimension.

J Tiers
05-06-2013, 12:23 AM
Making the set of tap drivers for english threads, I thought I would try the metric taps.

being that most of the metric taps are US made, the shanks and driving squares all fit, so that the set of drivers for english threads also fits the metric taps up through 10 mm.

I suspect that in Germany that might not be the case, but with the example of the 6,35mm driving squares for socket wrenches, who knows?

boslab
05-06-2013, 12:25 AM
I spent most of Sunday fixing an assortment of problems on a US manufactured Case 1845c uniloader, after removal of about 2 barrow loads of manure/broken glass from inside the chassis I figure its history was recycling facility the dairy farm, anyhow I digress, the control linkages were totally sloppy so I figured it was due a service, what I found was a whole can of worms, imperial, metric in both fasteners and materials, loads of different hydraulic threads NP, Din, BSP, hours spent rummaging for taps like 1/4 x 28 NF 2 assorted pitches of metric, I wouldn't have been surprised if I had found LH British Standard Bicycle, as it was I did find a LH 1/4 UNF on a turnbuckle, however I'm not sure that was original or an old fence wire strainer that had been repurposed at some point in the throttle linkage ( actually for a solid rod linkage it's a fairly neat fix as you don't have to fiddle with tiny ball couplings at the ends)
I don't see a problem in mixing but if in this day and age a method of identification of either metric or imperial could be devised it would make life easier, like the notch on fuel gas nuts, maybe something like that.
I was fortunate that I had bought a blue point tap and die set at a flea market, I must say I do like the die stocks centering system, just rotate the cam plate to snug up the three jaws and your bang on.
But notably Metric tried to shoot itself in the foot when starting like specifying metric threads in a whole range of sizes, I found old taps and dies in my cupboard like M7, M2.5, M9, M11 and so on, just silly, the preferred sizes fixed that to a large extent but having fine and course pitches in the same size has caused me to resort to Helicoils on more than one occasion.
Keeps you on your toes I suppose!
Marl

whateg01
05-06-2013, 01:53 AM
...
But notably Metric tried to shoot itself in the foot when starting like specifying metric threads in a whole range of sizes, I found old taps and dies in my cupboard like M7, M2.5, M9, M11 and so on, just silly, the preferred sizes fixed that to a large extent but having fine and course pitches in the same size has caused me to resort to Helicoils on more than one occasion.
Keeps you on your toes I suppose!
Marl

I have run across M9 threads on a bicycle axle recently. And some equipment that I used to maintain at work used M2.5 screws, and a lot of them, on RF enclosures. Not that bad to work with, but sometimes hard to source in the right length and head.

I have been known to mix imperial and metric on occasion. Sometimes an imperial thread is too big for the space and the next one down is too small for the load. There is often a metric screw that is right in the middle and works great. I do try not to do that, but it happens.

Dave

MrFluffy
05-06-2013, 03:12 AM
Landrover was the king of mix and match until the freelander era. I had a range rover classic, and the front wings were held on by metric fasteners and the same area on the rear by imperial threaded fasteners but with metric sized hex's. When I was ordering new flexy hoses for the front, I had to go out with a pitch gauge and check them as the supplier couldnt tell by serial which it should be at which end. It ended up being a metric fitting one end and imperial at the calipers.
I have a '89 landrover 90 now (precursor to the defender) and that has metric and imperial fasteners mixed on the swivel hubs which you cant change (ie if you change the swivel housings to metric you have to replace your brake calipers with metric ones too), and mostly metric elsewhere with the odd fastener lying in wait for the unwary (9/16th propshaft bolts etc). Makes buying replacement fasteners and sorting stripped threads out fun...

J Tiers
05-06-2013, 08:22 AM
But notably Metric tried to shoot itself in the foot when starting like specifying metric threads in a whole range of sizes, I found old taps and dies in my cupboard like M7, M2.5, M9, M11 and so on, just silly, the preferred sizes fixed that to a large extent but having fine and course pitches in the same size has caused me to resort to Helicoils on more than one occasion.

Marl

M2.5 is alive and well as far as I know. Widely available here, McMaster has them, and so do others. CAD programs have that as a choice.

What's the problem with fine and coarse threads? Each has their place.

John Stevenson
05-06-2013, 03:24 PM
Got a few CAD programs here and not one can thread worth a damn.................:cool:

lazlo
05-06-2013, 07:06 PM
Got a few CAD programs here and not one can thread worth a damn.................:cool:

LOL! -- that's the ultimate answer to standardization. As one of the Electronic Leadscrew packages advertised, you can thread in Inch, Metrich, or Klingon :)