105 Cassette, XT hub - mix'n'match?

[MrMajestic]

Here's a puzzle. I used to have a rear wheel which had a Deore LX hub with 10 speed freehub. This wheel had a 10 speed Tiagra (4600) cassette fitted (by Planet X). As I recall it did not have a spacer between the cassette and the spokeside freehub end. I now have a new rear wheel. It is built onto a Deore XT hub with 10 speed freehub. This time I am trying to fit a 105 10 speed cassette (5700). Now here's the problem. If I fit the 1mm spacer that came with the cassette onto the freehub and then mount the cassette I cannot get the lockring to engage on the thread. Certainly not enough to want to start turning it with a large wrench to the 40Nm recommended. If I try without the 1mm spacer I can engage the lockring easily enough and get a couple of turns on it. However it does not tighten far enough to completely remove all slack and there's slight cassette wobble. So question 1 is......spacer or no spacer? Second puzzle. If I remove the spacer, which is 1mm thick, then I seem to be able to 'buy' more extra space than that when I tighten the lockring. Almost as if the spacer itself does not fully bed onto the freehub. Question 2 - is there a more effective spacer on the market for this cassette/hub marriage?
At worst I suppose I could wet'n'dry the 1mm spacer down to about 0.5mm instead. Bit of a PITA to do though.
Ideas???

 

[mrbikerboy73]

I recently replaced a 10 speed HG cassette with a 105 10 speed cassette. At first, I could not get the lock ring on with the spacer, and without it, there was play in the cassette when the lock ring was tightened up. Unhappy with this, I tried again with the spacer and this time it fitted as it should have done so I'm not sure what I was doing wrong. The lock ring only just went on with the spacer but I'm glad I had another go at it. It should go if all the sprockets are lined up correctly.

 

[MrMajestic]

Wonder if it helps to remove the very thin spacer that's on the lockring? I did try to fit it complete twice but to no avail.

 

[MrMajestic]

MrBikerBoy73: Taking a leaf out of your book I went out to the garage to try it for a third time. Lo and behold it worked! I reckon the trick is mounting the final, smallest sprocket securely. Anyway, thanks for giving me the patience

 

[mrbikerboy73]

@MrMajestic I think the very thin shim on my lockring disintegrated after a couple of attempts but never mind, it all works as it should. Glad you got it sorted out