There is a book in the Workshop Practice series specifically on ‘Spindles’. I have not read it but it may contain the information you need.

Please do not take this the wrong way, but to me, your question is of the “can you please do my homework for me?” type. If you were to present it as “I have done the following research on my homework topic and discovered these resources. My outstanding questions are…”, you might reach your goal a lot sooner.

What prior art in the field of Model Engineering have you studied? The Quorn has been mentioned above; there are other cutter grinders within this hobby such as the Kennett, Stent and Bonelle.

What prior art in the toolpost grinder field have you studied? There is the ‘Little Giant’ toolpost grinder, the DuMore model, the Dynamic (Hemingway) and Duplex.

The technical libraries of the various bearing manufacturers would be a good place to start (e.g. https://www.skf.com/uk/industries/machine-tools/products-and-services/bearing-solutions)

https://dynospindles.com/vault/technical/Book-of-Spindles-Part-1.pdf

https://dynospindles.com/vault/technical/Book-of-Spindles-Part-2.pdf

Harprit Sandhu’s ‘Spindles’ is good place to start, there’s discussion of the choices confronting the builder of a spindle, some pointers on ‘method’, as well as ‘words and music’ for a number of designs that can be built as presented or used as a basis for something incorporating your own ideas.

https://www.arceurotrade.co.uk/Catalogue/Books/Spindles-WPS27

It’s clearly not the Treatise on the subject, but you will know more after you’ve read it than you did before, and in any case £7.21 won’t break the bank (and I daresay is a bit cheaper than the Quorn paperwork.).

Talking of ‘words & music’ I’m pretty sure that Lawrence Sparey published a drawing for a toolpost grinder in his ‘The Amateurs Lathe’, but IIRC it’s presented at a small scale and I think the ‘how to’ is very limited – however if you’ve already read Sandhu, you’ll be better placed to figure it out, and it’s a good design.

On 5 March 2024 at 11:08 Stephen Osborne Said:

I would appreciate any help in the form of plans, diagrams etc especially with the siting of the bearings, fits & tolerances and pre-load.

There is an excellent SKF publication that goes into detail about these things:

Link

(Especially P57 et seq.)

On the subject of spindles there is some good info if you go to https://www.schnorr.com and click on their “Downloads” “Literature” and download their “Design Handbook”. There is a lot of good useful info on using Belleville (Disk) springs to pre-load bearings.

John

I wanted a grinding spindle for grinding the jaws on chuck which was well out of true and could be used for engraving as well and found that I could buy a high speed spindle which will do what I needed for a lot less than making one from scratch. It was easy to use the bracket which comes with the spindle and also made a bracket to fit the spindle to my mill.

there is a video of grinding the chuck here      https://youtu.be/2VKR45MYVEwre.

david

On 7 March 2024 at 07:30 David George 1 Said:

I wanted a grinding spindle for grinding the jaws on chuck which was well out of true and could be used for engraving as well and found that I could buy a high speed spindle which will do what I needed for a lot less than making one from scratch.

I’m pleased that you’re happy with it, and very pleased to see that you have fitted an earth lead in the video – the power supplies that come with these spindles aren’t isolated from the mains.

Those spindles are just glorified motors though, running on ‘skateboard’ bearings in rubber cups, with wave washer preload. They aren’t very rigid at all.

I know because I struggled with one and tried to improve it. I eventually gave up and built a separate spindle, using the ‘ebay special’ as a drive motor:

(Some background here and here )