Uniglide cassette question (shimano 600)

[Spibblo]

As you know Uniglide cassette sprockets are all individual with a thick plastic spacer between each one.

Where does the thin steel spacer go?

I thought it went on last under the smallest, threaded sprocket. However, having reassembled the cassette, the space between the last sprockets is slightly wider than the others.
?
Does thin spacer go on first between the largest sprocket and the freehub body?

I'll be using friction shifters so I don't suppose the difference matters but if I were to use indexed shifters this would not work.

Where have I gone wrong?

 

[Simplex]

I seem to remember the early cassettes were bolted together and the 1mm spacer allowed the last sprocket to screw on without fouling the ends of the three bolts. The later 600 did away with the bolts and the last sprocket had a thicker built in spacer making it 5.5mm overall. Maybe you're putting a later sprocket on an earlier type cassette.

 

[Spibblo]

That's it!

I had combined two cassettes as the first two rings on the one I want to use where worn out. It's 2 rings from a close ratio 6 speed and the rest from a wider ratio 7 speed, with the 4 plastic 6 speed spacers.

I should have measured the threaded rings first.

Cheers