Tuesday 25 June 2013

Holy Steuerpimpel!

It seems to be raining turntables around the home front, especially Dual turntables. Actually it has rained Kenwoods and Technics as well but that's for later.

Dual 1242

I brought home for repair 3 different Dual 12XX series tables lately and in the last 2 days have worked on all of them. The 1225 has already gone back to the owner but I still have the 1228 I brought home yesterday and the 1242 from today. Even the ones that I still have I made progress on though and they should be working well soon.

Among other issues the 1242 above had a stylus that was nearly gone and the 1228 below had no stylus whatsoever. Both of them and the 1225 all had the most common Dual problems.

The mechanism of the Dual changers has a lot of moving, pivoting, sliding, rotating parts. All of those have some need for lubrication either by oil or grease. That lubrication gets dried and caked and stops doing the job very well. Another area needs little to no lubrication and in fact relies on just a bit of friction to operate.

That area controls the movement of the tonearm during the Start phase in automatic mode and the Return of the tonearm at the end of the record side. It relies on a steuerpimpel to do the job. A what? A steuerpimpel. It's a little plasticy bumper that sits on the clutch pin and slides against a platform taking the tonearm with it during the arm start and return action. When the needle is on the record it sits a bit away from the arm and the arms nearly friction free.

This pin is where the steuerpimpel goes. (Seinfeld to Costanza: "You just like saying that don't you?")

Dual clutch pin

The steuerpimpel almost always fails after 30 years or so. The piece just disintegrates and breaks apart. When it does the arm won't move properly if at all. The part is also not that easy to find but also is easy to fabricate once you figure out what to use. I tried heatshrink tubing, small sections of the end of pen refills and other sizes of wire insulation but settled on 14 gauge insulation as it seem to provide good performance and fit.

Steuerpimpel in progress


16 gauge might work but 14 goes on easily and when cut nicely to the right length seems to work well. The 1242 has a longer pin and seems to prefer about 6mm long but the other 2 are best with 4mm. The key is that it should be just a bit longer than the pin itself so that the metal does not stick out. The smaller piece shown is about 4mm and the longer is around 6mm. Below is the longer one once installed.

Dual clutch pin 2          

I love simple fixes. That's not to say that every Dual turntable problem has a simple fix, but this one is not bad once you work out a few details.

Aside from that these turntables work amazing well after so long that I am starting to enjoy working them. I still have some other details to address on both the Duals sitting here but once again, another day...


4 comments:

  1. I love my 1228, the steuerpimple is still in tact, but I'm already planning on pre-emtpively replacing it. Was planning on using a length of pen refill, but think I'll go this route now. Thanks!

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    Replies
    1. I am kind of the "if it ain't broke don't fix it" sort but if want to go replace it go right ahead. If your steuerpimpel is still working, maybe I would leave it but perhaps it was even replaced at some point in the past.

      You can always check 16 gauge wire as that is the more common household variety. Hardware store guy just gave me a piece of the 14g stuff you see but if this did not as work as well as it seems to do I would try other stuff too.

      I would suggest cutting it with proper wire strippers such as you see in the picture. These give it a nice straight cut and also roll the edge in a bit with might help give a smoother action. Cutting with scissors or a knife might not work as well, leaving an angle for example.

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  2. Hi ...

    Nice blog !
    I have 2 DUAL 1225's and my question is :
    Is it necessary to de-grease the moving parts and replace with high grade lub ?
    if so, do you have any tips?

    greetz from the Netherlands

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  3. Thanks!

    I won't say it is ABSOLUTELY necessary to de-grease everything but it won't hurt. Alcohol and cotton swabs (Q-Tips if you have those in Holland) help a lot. If it is really crusty definitely get rid of it, perhaps even scraping it away with a screwdriver tip to start.

    Re-grease with white lithium, oil the motor with something like 10w30 motor oil. I often use something a bit thicker for platter bearings. Chain oil, as in bikes and chainsaws, works well for that.

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