Lead Retainer

The image to the left is a rendition of a lead retainer, highly enlarged. A lead retainer is a small rubber device that fits into the end cap of an automatic pencil just before the lead sleeve opening. The device is used to keep too much lead from projected when the push button is pressed to project the lead from the end of the pencil. Although tiny it is a very important part of the inner workings of the pencil. The lead retainer is a press fit and held in place by friction. It is not supposed to come out yet over the years I've removed the end cap from one of my many automatic pencils only to find this little device midway along the protruding lead. Fortunately I have always managed to get the device back in place with considerable effort. In one case I had to super glue one in place in order to keep it there.

Recently while working on 2 Koh-I-Noor 5633 pencils I somehow, unknowingly, managed to lose not one but both of the lead retainers from the 2 end caps! Needless to say this caused both pencils to become useless. Besides keeping the lead in place the lead retainer also helps keep the lead from moving around inside the lead sleeve. The pencil's chuck will hold the lead in place as long as the lead is not too short. But since the tolerance between lead OD and lead sleeve ID is greater in some pencils than others the lead can move around inside the lead sleeve causing breakage. I was miffed to say the least.

I tried to replace the lead retainer with a small piece of rubber that I had punched out of a sheet of rubber using a leather hole punch. Using a number 78 drill bit I tried 'drilling' a hole in the rubber piece. I tried holding the rubber cylinder and drilling a hole by hand using a pin vice but that failed. I tried pushing the cylinder of rubber into the end cap and chucking the drill bit into the pencils lead chuck and slipping the end cap back onto the pencil, drilling as I did so. This failed as well. So consequently I put the pencils aside and gave them up as lost.

More recently I received some parts to fix up a couple of Pentel pencils. Unfortunately one of the end caps was missing the lead retainer. This drove me back to try and figure out a way of producing a workable lead retainer. I had a piece of 'Fun Foam', a sheet of neoprene rubber sold in craft stores. I gathered the end caps and pencils together along with the neoprene sheet, my X-acto knife, numbered drill bits and determination to get it right and set off again.

This time I simply cut the rubber into small squares. Placing one square into the end cap of the Pentel pencil, I pressed it into place using a drill bit to big to puncture the rubber square but small enough to lodge the rubber in place. I then put the #78 drill bit into the jaws of the pencil's lead chuck and slowly 'drilled' the rubber piece as I screwed the end cap back onto the pencil. It took a couple of tries before the rubber stayed in place. Projecting a bit of lead from the lead chuck of the pencil I slowly replaced the end cap onto the pencil. The lead came through! When I clicked on the push button the lead did not project too much! Before calling it a success I made sure that the lead would self thread through the makeshift lead retainer. It did so just fine.

I next tackled one of the Koh-I-Noor end caps. It took a bit more work in order to achieve success but I was able to do so at long last. I had now successfully restored 2 of my once defunct pencils! I was to exhausted (mentally) to continue with the 2nd Koh-I-Noor end cap, besides I really had no need for it right then as the pencil it belonged to had died an unnatural death, so I put it aside for another day. But now I no longer fear so much the loss of a lead retainer as I now know that indeed I can at least 'fix' the problem with a workable makeshift solution until I can find a real lead retainer, which is of course the best fix.

Added 11/13/2008. After some time I discovered that my "Fun Foam" lead retainer did not hold up, or rather stay in, like I was hoping. So what I ended up having to do was to super glue the makeshift retainer in place. I DO NOT recommend that anyone do this except as a last resort. I have given up hope of ever obtaining a new lead retainer for any of my pencils so this was not such a drastic step for me. However if there is any possible way that a real lead retainer may be obtained super gluing the makeshift one in place would make it almost, but not quite, impossible to remove. Removable would require the use of acetone (nail polish remover) and maybe several sizes of small, number sized, drill bits and some hard work. I apologize for any inconvenience this may have caused anyone.