Universal 123-Block Hack ?

[Lo-Fi]

These are excellent, by the way:

Stevenson's Metric Blocks - Arc Euro Trade

Precision ground steel packing blocks with 8 TAPPED and 8 CLEARANCE holes. Now in three sizes 10x20x40mm, 15x30x60mm and 20x40x80mm

www.arceurotrade.co.uk

Not too spendy, clearance and tapped holes, precision ground. I have a small set, they're an absolute joy to work with. I have Stephensons collet blocks too, which are also excellent.

 

[graham-xrf]

Hee Hee - It may be "off topic", and maybe somebody will come in with more great stuff about 1-2-3 blocks, but I don't care. Let's chase this down.

The 0.197" translates to 5.0038mm. The 38 hundredths of a mm is about 149 millionths for imperial folk. Your measure was pretty good, because a real 5.0mm is 0.1968" We may take it that the pitch of the cross slide screw is 5.0mm. That is more than I was expecting, but is perhaps reasonable.

Looking at the dial, and taking a guess, it looks like 100 divisions, and it has a vernier. On division on the cross slide dial moves the tool 0.05mm radius. Therefore that division takes 2 x 0.05mm = 0.1mm off the diameter.
Using the vernier allows to move it by a tenth of that much, so the smallest vernier increment amounts to 0.01mm (off the diameter).
Have I got that right?

When you say "handwheel", do you mean for the left-right carriage movement. You mentioned it had an imperial threading leadscrew.
I am going to chase down everything there is to know about South Bend metric lathes, and lathe conversions, and put it in it's own thread, after I have got it truly figured out, because I mean to make some changes to mine. Perhaps I draw the line at using an imperial lathe to turn up a metric ACME lead-screw for the same lathe. There are tricks that lets one make it change it's spots, and keeps the gearbox in play, without going to such lengths.

 

[graham-xrf]

These are excellent, by the way:

Stevenson's Metric Blocks - Arc Euro Trade

Precision ground steel packing blocks with 8 TAPPED and 8 CLEARANCE holes. Now in three sizes 10x20x40mm, 15x30x60mm and 20x40x80mm

www.arceurotrade.co.uk

Not too spendy, clearance and tapped holes, precision ground. I have a small set, they're an absolute joy to work with. I have Stephensons collet blocks too, which are also excellent.

Thanks much for the link - and of course, it is a UK supplier. I will likely be getting some of these!

I got stung twice by the "new" post Brexit arrangements, even though the transactions were done back in December. Things are very much not as Boris had promised. Unless you have a UK distributor who has taken care of the supply chain, any import over £135 then has the VAT and duty taken at the port rather than the supplier. The transport shipper (Fedex, DHL, whoever, has to pay the VAT, so they send you their separate bill later) Also, Govt. helps itself to £11 additional "fees", just for the hell of it. Also, the price got hiked by the vendor to pay the customs duty, if there was any.

Goods less than £135 has it that the VAT and duties are taken at the shipping point, rather than the port point. If you want import hell, just try and buy a Precision Matthews Lathe!

 

[Lo-Fi]

I feel your pain. I'm super careful with purchases now!