Tombow SH-1000LP lead advance

I was happy to get a Tombow SH-1000LP in very good condition but when it arrived I found out that the lead advances about 2 mm per click which is of course too much. Is this normal for this pencil? If not, how does this happen? Am I right in assuming that nothing can be done about this?

I’ve seen some pencils do that — not specifically Tombows… Did you try removing the old lead sticks and using new ones?

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That solved the problem :smiley: Thank you!

However, there is still one small anomaly. When I push the lead back into the pencil with the button pressed, I feel almost no resistance, just as if the lead retaining ring was missing. And the lead avances differently: With the tip pointing downward I get 8 mm per 10 clicks and with the tip pointing upwards I get 6 mm per 10 clicks. Maybe the retaing ring has hardened over time or is missing (and the sleeve has such a low tolerance that the lead cannot slip out).

Anyway, the pencil is usable again :grinning:

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Yes, probably — or is looser… I have a beautiful Elastichuk that I never got to use or even try out because the rubber gasket hardened over time and it doesn’t let the lead through. Was a bit disappointed when I contacted the seller (a rather notorious seller of vintage pencils on ebay…) and he simply told me yeah that happens try wd-40 which he had previously drenched the pencil with… I was hoping he could find a replacement for me, but no luck.

You used to be able to find Elastichuk gaskets for sale on ebay (Dietzgen apparently was aware of this happening often so they made spares available) but I haven’t seen them for sale in ages now. Maybe one day.

Btw, you can easily see if the retainer ring is there. Well not easily… but it is possible. Finding one and putting it there is much harder… Maybe you can find a match in another (cheaper) Tombow and replace the entire tip.

PS. Glad to know changing the lead did the job! :v:

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Thank you for these additional details!

I looked in the top and saw only metal, and so I think the ring is not there. I will try to find a matching ring or tip but since the lead doesn’t slide out (as it did in an old rOtring pencil I once had) and the pencil can be used there’s no urgent need.

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Yeah, it can be a tricky thing to diagnose, as the lead retainer can be tucked very deeply into the nose cone. And this isn’t a part you can source separately.

Whenever I’m having lead advance issues, my first step is to remove the nose cone and then see if the mechanism still works (you have to manually release the chuck lock). Swapping nose cones is another way… if you’re lucky enough to have 2 of the same pencil, or another pencil within the brand that has a compatible nose cone.

I have a Pentel SMASH LoFt edition that is missing the lead retainer in the nose cone. I have a rather used black SMASH that I was hoping I could use as a donor, but I can’t figure out how to dislodge that retainer without destroying it. It makes me wonder if a slight variance in assembly leaves some of them with a little less adhesive than required… which then makes them prone to falling out.

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I don’t know if it happens as often with other manufacturers but I swear I come across more loose retainers in Pentels than any others. I don’t know if they were originally held in with friction and they shrank as they dried out, or if there was an adhesive that dried out, or what. But it happens with several different shapes of retainers from the 60s through at least the 90s era of Pentel.

When I see they are loose I’ve taken to using miniscule amounts of blue locktite applied with a fine needle to cement them back in. Run lead or appropriate gauge wire through the sleeve in the lead-advancing direction to push the retainer into place and then wait 24 hours for it to cure. Running lead or wire through it also insures any runoff doesn’t block the sleeve. I’ve had 100% success with this a couple dozen times now.

If you do this, definitely use low strength versions; purple is probably better than the blue level strength I’ve been using; it’s just what I always have on hand for machine screws. But avoid anything “permanent”, since someday the retainers might need replacing anyway.

On a related note, I have noticed that some lead manufacturers do vary in diameter by .01mm or .02mm, enough sometimes to slip through some retainers. I suspect that tolerances are tighter in modern manufacturing, but I have so much vintage lead from the '80s and earlier. :slight_smile:

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Good suggestions.
I had one that came out on a P205 and I used a little super glue on it… but I suspect it may not last (you don’t want an adhesive that is hard enough to end up cracking). I’ll have to pick up some Loctite.

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Ah! So it can also be sandwiched between other parts.

It looks like I have been very lucky so far :wink:

So maybe the diameter of the lead I’m now using in the SH-1000LP is a bit larger.

Thanks to everyone for the repair suggestions!

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Well, it’s possible depending upon the design. Some nose cones are long because of the pencil design, making it hard to see deeply into it where the retainer is located. It’s usually very close behind where the lead pipe ends. I don’t know if any maker bothers to “sandwich” it behind another part, because that would complicate manufacturing.

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That’s exactly the way.

I don’t think the retainer was lost, it probably lost some of its retainability over time. When there is no retainer the lead falls out of the pencil very easily, it doesn’t really work.

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