How do I dismantle a freewheel cassette

[levad]

I have a shimano (sorry!) mf-hg20 SIS 6 speed cassette which I would like to dismantle. It is from an old Raleigh Nitro that I am trying to convert to single speed (not fixed yet as I have too many hills to go down on my commute). I want to use the freewheel portion of the cassette and the 18 toothed gear, I plan on making some spacers.

I have removed the cassette from the wheel and I think I need to remove a lock ring but ... I don't know which way it is threaded!! I have no special tools and have just had the cassette in a vice and been trying to persuade the lock ring to move with a hammer and drift punch.

Am I going about this the right way?


HELP PLEASE

 

[TheDoctor]

Hang on...I reckon you've got a freewheel there, not a cassette.
Don't dismantle it, just get a single speed freewheel. Costs about £8 ish.

 

[levad]

Yes, I think it is a freewheel not a cassette. I could get a single speed freewheel but I don't know yet how many teeth I want. I though if I could dismantle what I have got then I would have several options to try.

 

[Aperitif]

levad - I think the Doc is right and you will muck everything up if you dismantle the existing cassette. Why not pose this question in 'Fixed and Single Speed' - there is bound to be someone who has done exactly what you want to break do. :

 

[swee'pea99]

I had always been led to believe that the correct answer to the question posed is: don't.

Am I missing something here? You say you want to try out a number of options before settling on one. Fine, that seems sensible. Can you not just leave the freewheel on the bike and ride it for a few days in different gears each day but without changing gear during any given day? Surely that would be the easy way to achieve what you say you want to achieve?

 

[levad]

Thanks all. I think swee'pea99 is right I will try that approach.

 

[tyred]

These come apart easily enough. The smallest sprocket is the lock ring and unscrews in the anti-normal clockwise manner. Find a way to hold the largest sprocket and wrap an old chain around the smallest and clamp it together with vise-grips to unscrew. Make up some spacers to replace the sprockets you want to remove and tighten the small sprocket to keep it in place. The problem you may encounter is that the splines that the sprockets sit on on a threaded freewheel are stepped so you have limited options to change them round. You'll probably find the largest three are interchangeable and the smallest two are interchangerable.

 

[TheDoctor]

Or buy an 18T freewheel for about £8

 

[dellzeqq]

or cheaper yet - find the gear you like, put the chain on to that gear and just leave it there. I await my portion of your £8 saving

 

[rich p]

or cheaper yet - find the gear you like, put the chain on to that gear and just leave it there. I await my portion of your £8 saving

I've often thought that a good solution myself. Maybe the temptation would prove too much for the weak minded!

 

[tyred]

or cheaper yet - find the gear you like, put the chain on to that gear and just leave it there. I await my portion of your £8 saving

But where's the fun in that?

And think of the weight of five unnecessary sprockets

 

[levad]

But where's the fun in that?

And think of the weight of five unnecessary sprockets

Exactly, and I need the perfect chain line