Where can I get very small (2.5mm) precision shim washers

I've Googled for ages without success so I thought I would ask here.

I am using some small ballraces (3mm ID, 6mm OD, 3mm wide) which are installed in a 3.5mm wide 'U' shaped slot (made with a Woodruff type cutter) so that some of the circumference of the outer race sits above the surface of the part to act as a rolling support.

I need washers with 3mm bore and maybe 4 or 4,5 OD. The thickness needs to be about 0.2mm as I will alter the slot width to suit whatever I can get.

Most Google results end up linking to shim and foil manufacturers, what I want to find is someone that sells ready made washers.

Ian

Shim steel and a punch & die set

Hi Ian

I may be able to help you with this, but it will be tomorrow morning before i have a look. How many do you need ? no promises but will do my best.

Cheers Derek.

Ian

Make them from shim, clamp some shim between two peices of plate and drill the 3mm hole then put them on a mandrel with washers either side of the shims and turm to the diameter you want.

Olly

Ian,

Have you considered nylon shims?
3x4.5/5mm might be difficult to get but see

http://www.rapidonline.com/Mechanical-Fastenings-Fixings/M3-Plain-Nylon-Washer-Pack-100-33-5064

They do 3x8 which can be put on a 3mm mandrel, tightened up and skimmed down to your 5mm O/D
Cheap as chips as well!

Bob D

Ian,

Try a company called "Pinstructure" in Redditch, they do shim washers from a 10th of a mm thick up to 1mm thick, and loads of other useful fixings etc. 01527 67999 .

Richard.

Thanks for all the replies which have given me food for thought.

Ideally I would prefer the washers to be stainless steel, or at least some non corroding material. I had discounted making the washers myself because I could not see how I could drill/punch/turn etc and not end up with burrs bigger than the material thickness. I suppose I could lap them on and oilstone but making 24 washers 0.2mm thick with a 3mm hole and an OD of 4.5mm would wear away my fingertips.

One of the members has offered me some washers that sound ideal so my search is really over.

I contacted the Pinstructure company suggested by Richard, They do have shim washers 3mm and upwards in carbon steel from 0.1mm thick so they are another possibility. Their website has all sorts of 'hard to get' products so is definitely worth looking at. Actually the website make them hard to find as well, even after you register (which you need to do just to look at pages of the catalogue).

Ian

One thing you might want to keep an eye out for - for this and in a general sense - is laminated shim washers. They're punched from (not surprisingly) laminated material, usually brass or corrosion-resistant steel with, usually, .002" laminations.

You then peel layers off them to get them to a suitable thickness to shim your bearing or whatever. They are used a lot by manufacturers of precision mechanisms. harder to find than they used to be but worth their weight in gold when you do.