Mechanical Pencil Lead Pathway Obstructed - What To Do?

[MYU]

I have a nice Tombow all steel mechanical pencil that is essentially new with sticker. I got it along with a couple of other pencils.

 

However, this mechanical pencil has a problem. I cannot get the lead to come through the lead reservoir. So when I take a lead and feed it backward through the clutch opening, it goes for about 2cm then stops dead. Now, if I put the front piece back in place, the lead will advance forward. So that is working. But I'm perplexed as to how the lead pathway is blocked. I even tried pressing slowly and firmly on the extended lead (trying not to break it) to see if I could force out whatever is stuck... and it didn't work. I don't know... maybe it has a manufacturing defect? I can't think of what else could be wrong. One other MP I had suffered a similar kind of blockage ended up being a desiccated eraser stuck inside it, but that wasn't too hard to extract.

 

When I disassemble the mechanical pencil, I get only so far and then cannot remove the lead reservoir tube from the front section. I don't see any way to remove it so I can try further clearing. I do have some small thin metal pins that are used to clear lead pathways, but they are too short.

 

Any ideas? I'll try to take some photos later. Thanks!

[milkb0at]

Hmmm, doesn't sound encouraging.

 

I assume you've tried clicking loads of times to check that it's not just an existing lead taking its time to come through? Other times I've had too many leads in the reservoir and they've all jammed together, so a few sharp taps upside down onto the table helps dislodge them and get the pencil working again.

 

If it fits, an unwound paperclip might work as a lead clearer, but that might only work with larger lead sizes.

 

I'm sure I've tried blowing into the pen (with the clutch open) but I doubt that's ever worked. Might be worth a shot.

 

Most of my pencils have been Pentel and Staedtler, so I don't know if Tombow have some strange mechanism.

[Inkdot]

This may sound weird, but perhaps a guitar string may be helpful.

[MYU]

Thanks for the suggestions. It seems that there is something in the tube, and it's not lead. I've dealt with mechanical pencil jams before, and nothing has worked. I even tried putting a flat head needle down the reservoir and pushing on with a metal ballpoint refill... and it would stick in, but not clear whatever is inside it. And with pushing back on a long piece of installed lead, I provided plenty of force before the lead started to break. It's very peculiar. It's a nice quality all steel mechanical pencil, but I've come to realize I'm spending more time on it than it is worth. If it was some kind of $50+ mechanical pencil, I'd probably try a bit more... but given it's probably worth less than $20, I have to abandon...

[NinthSphere]

You don't mention the lead size or model. Is this a clutch pencil? Is the lead advanced with a rod?

 

I'm not really familiar with Tombow pencils, but a model name or pic would go a long way to clarifying the situation.

Edited April 19, 2017 by NinthSphere

[bearcat1]

I would try a longer metal wire fed from the front to try and dislodge whatever is stuck in it. You might try holding the pencil upside down and tapping the reservoir on a table top while pushing the metal wire from the top.

[NinthSphere]

Depending on the type of pencil, you may just be shoving against the mechanism used to advance the lead, in which case all the shoving of needles & wire isn't going to help matters. The lead resevoire may in fact just be storage, completely isolated from the advancement mechanism.

Edited April 20, 2017 by NinthSphere

[kestrel]

I use piano wire to replace hinge pins in old lever fillers. PM me if you would like a piece to try in the Tombow. It's stiff, thin, and I have 20 meters of the stuff.

[RMN]

How about using a sewing needle to clear the tube?

 

 

D.ick

[milkb0at]

Sounds like a project pencil to return to when you're bored. Hopefully you'll figure it out eventually.

[MYU]

Thanks again for the suggestions. Sorry for not having provided more info upfront. It's a TomBow Mono 0.5 mm. The reservoir is designed like most pencils, to allow the lead to feed automatically.

 

The lead clearing wires usually included are far too short, but I got a nice longer one with some PILOT MP erasers (they provide 2 thicknesses, which is very nice of them!). But those are still too short.

 

Hey Dave (Kestrel) - is the piano wire 0.5 mm thick or less? If it is thicker, I'm thinking that there may be a thinner wire to be found from a hardware store. Not a high priority, given the cost of the pencil, but on my next run it might be worth while to look into if they've got it.

[kestrel]

Thanks again for the suggestions. Sorry for not having provided more info upfront. It's a TomBow Mono 0.5 mm. The reservoir is designed like most pencils, to allow the lead to feed automatically.

 

The lead clearing wires usually included are far too short, but I got a nice longer one with some PILOT MP erasers (they provide 2 thicknesses, which is very nice of them!). But those are still too short.

 

Hey Dave (Kestrel) - is the piano wire 0.5 mm thick or less? If it is thicker, I'm thinking that there may be a thinner wire to be found from a hardware store. Not a high priority, given the cost of the pencil, but on my next run it might be worth while to look into if they've got it.

.508 mm 8 Gauge.

[MYU]

Hey Dave, sounds like that would do the trick! Even if it ends up fruitless with this particular pencil, it would be nice to have this wire for cleaning/clearing out other pencils. Maybe ones where the lead advance works but has more friction than usual just might be suffering from some minor build-up that is smoothed over by the lead instead of purged, and would be effectively cleared out with the wire. PM sent.

[octatonic]

Please report back with an update

 

Thanks!-

 

octotonic

[kestrel]

Wire outbound on Friday.

[MYU]

Thank you, Dave! I'll let you know when I've received it. I'm hoping this will help clear the pathway and I'm very curious to know what is causing the obstruction... presuming it can be cleared (who knows, it might even be defective, because the pencil still has a sticker and no signs of use).

[MYU]

Got the wire, Dave. Tried it... and...

 

 

it worked!

 

 

And wow, was it ever an obstruction. At first the wire hit the obstruction... and nothing. I went back and forth with the wire, tapping harder and harder. Nothing. And then in desperation, I applied brute force and -- CRUSH -- plowed through it. It was desiccated lead. TOMBOW must have used some cheap stuff. Hard as rock. The wire was the only method that would have worked. Not even the strongest lead would have been able to plow through it.

 

I had 2 other pens that had lead flowing issues and this wire snake cured them as well. So, thanks again! You saved me the time and effort of having to track down the wire. This is going into my special multi-purpose micro tool box for all time.

Edited May 4, 2017 by MYU

[milkb0at]

Fantastic news. Well done.

 

Now we just need a photo of the pencil

[MYU]

Fantastic news. Well done.

 

Now we just need a photo of the pencil

 

It's not anything super unusual... but it's a nice pencil. Very well made, for 1,500 JPY.

 

[milkb0at]

Thank you. That's a nice looking pencil, and different to your nice Pilots.