The original post referred to a product where there the ammonium bifluoride is in the form of a cream or paste and thus less likely to splash. Even so, good safety specs or a full face visor, proper gloves (i.e. Marigolds rather than a thin disposable gloves) and a plastic apron. There is an interesting discussion at https://www.finishing.com/94/62.shtml.

If there is a taper it is very slight, I measure the dia. at 22.04-22.10mm with the digital calipers. It´s too tight to get my little micrometer in. Eyeballing it I would say there is no taper.

The boss on the end of the PD230 spindle is about 22.04mm in diameter and protrudes about 7mm. (At least on my model which dates back to 2006.)

PS. Don´t confuse the PD230 and PD250, I'm not sure their chucks etc. are interchangeable.

Dick.

Probably fiendishly expensive but you could give this lot a ring: (the Precision Plastic Ball Co.) - https://theppb.co.uk/.

Daft suggestion, print the pulley in two halves and screw the two halves together.

In German but with photos.

https://forum.zerspanungsbude.net/viewtopic.php?t=11546

Hope this helps. Search under Walter Teilapparat.

Just use silver steel and harden the ends afterwards, blue pivot steel can be a pig to work.

Which version of the JW 8 Day Wall Clock are you working from?

Does the USB stick show in Disk Management? I forget how to get to it in Win 7.

Resist all requests to format something!

It might be something as simple as the USB disk not having a name or a letter (H:,J: etc),. In disk management look for a disk with the right size.

Google USB, Win 7 and Disk Management. I´ve had one of these but it was a while ago.

How about polystyrene (eg. CD case) or a bit of Lego (colourful ABS) dissolved in acetone to make a paint? Use acetone again to remove.

How hard are you abrading it?

I´ve got one of their bandsaws, it works and you can get spares here. Else it looks like many other offerings. The first think it did was to eat the rubber tyres that drove the blade. Dick.

Press any key to continue. Where´s the "Any Key"?

If is was you I wouldn´t have started from here

Just to give the pot a stir, I looked at a German Proxxon dealer´s site and they sell a set of ER20 collets for the FF400 for machines with a serial number beyond 401-10910 manufactured after 05/ 2012. Before then I think they used the Proxxon style collets with slits from the front face. Around 2012 the ER20 collets became the norm, hence the confusion. See https://www.fluidonline.de/proxxon-24304-81-ersatz-spannzange-12mm-fuer-ff400-pf400_3629_4029.

Dick.

Look at the annular slot that locks into the tightening nut , then you understand how it works.

I think the Proxxon collets are a special design, you have to engage the collet in the nut before you tighten it in the spindle. Conversely if it doesn´t disengage on loosening you have to jiggle it a bit until you can remove it from the tightening nut. I hope this is clear but I don´t know the correct terms to describe this. I have a Proxxon FF230 (notmy choice) and I know if the collet is not properly engaged it will move in use.

See this one on fleabay.de

"Sehr schöne dekorative antike Uhrmacher Drehbank Messing auf einem Holzsockel"

it could be its twin but with the rest,.

Maybe a nickel alloy. Have a look at Espacenet patents search and put in Metcal and browse the results.

See

patented by Otto Paul in 1926.

https://worldwide.espacenet.com/patent/search/family/007386036/publication/DE479442C?q=%20wasserwaage

How about using it to decide whether the upper surfaces of two plates/ or railway tracks are level before welding / tightening a joint?

In Germany people swap from summer to winter tyres end of October / early November. The winter tyres have a grippier profile and lots of little ribs like slits or vanes in the tread pattern which are supposed to pump more water as well. The ADAC (the German equivalent of the AA ) publishes tests on summer and winter tyres (https://www.adac.de/rund-ums-fahrzeug/tests/reifen/) every year rating the tyres for grip, braking performance, noise and fuel economy.

I do so miss the daily commute, every November when we got the first dusting of snow you would find those who still had the summer tyres on creeping along in the slow lane. If you don´t have the appropriate tyres on there´s a fine and a point on your licence.

Try TinkerCad. For creating simple solids and assembling blocks and putting holes in them to create an .stl file it does what I want for 3D printing.