SL-7 damper mechanism for lowering tonearm

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SL-7
England
Posts: 1
Joined: 24 Oct 2019 18:48

SL-7 damper mechanism for lowering tonearm

Post by SL-7 » 22 Nov 2019 20:52

Hi, the tonearm on my Technics SL-7 was dropping quite quickly - having read a bit about it, the issue was that the damper mechanism needed to have its silicone fluid renewed. So, I thought I'd pass on how I managed this (without breaking anything).

The two main bits I needed up front were :

- a small allen key (I think it was 1.3mm, I had to buy a set of smaller sized keys for this)
- silicone fluid. This is available in different viscosities, for radio control cars. I used 30,000cst, I'd probably use
40,000cst next time!

So, the first part was to remove the damper unit out of the tonearm assembly. Move the tonearm across, so it's say in the middle of its range of travel. From the picture below, you can see I've arrowed the grub screw that needs to be unscrewed with the allen key.
grubscrew.jpg
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Unscrew the grub screw, and the damper assembly is loosened (I removed the grub screw and put it to one side). I had to move the tonearm about in order to remove the assembly, but the assembly came out fairly easily. In the picture below you can see the hole for the grub screw (arrowed) and the larger hole for the assembly.
damper1.jpg
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Now, we have the damper unit in one piece. Firstly make a note of the orientation of the spring, and remove that.
DSC_0222.JPG
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The barrel of the unit is held in place with a tiny! circlip. I took extra care over removing the circlip, as I was worried that if I dropped it, I'd never get it back. I used my fingernails to remove the circlip, so very little force needed.

With the circlip off, the barrel slides off, with a spring washer located under that. The picture here shows the five parts to the unit - the base, spring washer, barrel, circlip and spring.
assembly1.JPG
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Nearly there - I cleaned up the barrel and base with methylated spirits (but I'm assuming you could use other alternatives). Before putting the barrel back on the base, fill up the barrel with the silicone - it's quite thick, as you'd expect. With the spring washer on the base first, then put the barrel back in place. Surplus silicone came out, clean that up then put the circlip back on.

Then, put the spring back in place and put the whole assembly back into its housing, and tighten up the grubscrew.

With it back in place, I tried it out. It was pretty good - before, the tonearm dropped fairly quickly, afterwards it dropped at a more leisurely pace.

Thanks for reading.

clips
Norway
Posts: 4
Joined: 29 Oct 2019 15:55

Re: SL-7 damper mechanism for lowering tonearm

Post by clips » 23 Nov 2019 15:27

Nice work! Will remember this post if my SL-7 ever get that problem. Thanks for a good post!

fscl
vinyl addict
vinyl addict
United States of America
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Joined: 05 Aug 2004 07:51
Location: CT, US

Re: SL-7 damper mechanism for lowering tonearm

Post by fscl » 25 Nov 2019 17:24

Excellent post, thank you SL-7 for your very detailed instructions on restoring correct cueing speed for the SL-7 and Technics linears in general......... =D> =D> =D>

Thanks again and welcome to VE....... :)

I've cross linked this post to "SL-7 Disassembly Problem" to keep troubleshooting of these units together / easily referenced.

Fred

Nephilim72
junior member
junior member
Scotland
Posts: 9
Joined: 29 Oct 2019 03:34

Re: SL-7 damper mechanism for lowering tonearm

Post by Nephilim72 » 27 Nov 2019 16:55

Excellent post! I have just bought a mint SL7 but the arm drop was just freefall. Glad to know it can be fixed and with not too much trouble!
Cheers

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