The Mitsubishi Uni 05 Super mechanical pencil

[cytherian]

This is one of Mitsubishi’s great looking pencils for ¥1000. I think it was one of their best sellers as a lot were made and they’re not all that hard to come across in light to moderately used condition.

Compared to something like the BOXY M5-1100, it’s very similar in basic body shape, nose cone, rear cap, and clip. But instead of the knurled ring grip, there’s prominent etching directly into the metal body filled in with black enamel. It looks really sharp when examined up close. Tactile feel is excellent. A nice touch is the 3 diamond Mitsubishi “star” that is also etched.

There’s 2 pesky things for me, though.

First, I don’t see any way of detaching the mechanism from the body! Even photos from other sources showing the cap and nose cone off never show the mechanism out of the body. I think it’s bonded in place. Maybe it was a cost savings. In any case, it’s all metal inside and the lead reservoir tube is metal as well.

Second, because the reservoir tube, cap and body are metal, there’s rattling to be heard if you rapidly wiggle the pencil. I don’t know what is the exact cause, what is hitting what. Mitsubishi just didn’t bother with inserting a nice insulating plastic sleeve. So, in effect, you could cut a thin piece of bendable plastic and insert it into place. However, there’s an even easier solution. Dryer sheets! When you finish laundry, don’t throw out that used laundry sheet. Take it, cut a strip, then using a toothpick, slide it into the Super Uni 05 body, nestled around the reservoir tube. It deadens the rattle perfectly and it’s easy to remove if you ever want to take it out.

NOS examples with stickers do come up from time to time with reasonable prices. Right now on eBay there’s sellers trying to eek out $60 USD plus international shipping, which is a bit of a stretch.

[Pdunc67]

Very nice post, Gary! - I am glad you wrote this - I had been on the fence about buying this one, thinking it was a silkscreen. But since it’s etched, I think I would like to pick one up!

@cytherian

However, there’s an even easier solution. Dryer sheets! When you finish laundry, don’t throw out that used laundry sheet. Take it, cut a strip, then using a toothpick, slide it into the Super Uni 05 body, nestled around the reservoir tube. It deadens the rattle perfectly and it’s easy to remove if you ever want to take it out.

that’s a great idea!

[cytherian]

Here’s a little photo assist on explaining what I did:

As you can see, you don’t need much. The last photo shows the dryer sheet segment still visible, but once you use the plunger a few times, you really can’t see it any longer (only a bright light and magnification will expose it). You might have some errant fibers sticking out towards the end, so just trim them off before the final submerging.

This is an extremely benign DIY. The soft fibrous swatch of dryer sheet is completely non-abrasive. Plus, it is easy to pack into place, which creates a terrific buffer. NO RATTLES whatsoever. I recommend using one that’s used up. A fresh one will have a smell… and with it being completely flat, it will be easier to insert but might not buffer on the rattling as well.

[cytherian]

@Pdunc67

I think I would like to pick one up!

Great! Happy to oblige. Sent you DM about the package.

If anyone else would like one, I’ve got 3 duplicates all NOS and stickered as shown in the photo. I’ll put up a WTS entry in the marketplace.

[Pdunc67]

Thanks Gary!

[Ras]

What I normally do is wrap some clear tape around the knock cap, which stops the cap from rattling inside the barrel. Then the lead tube also won’t rattle as it is fixed in place by the cap. It doesn’t affect aesthetics since the bottom of the knock cap (where the clear tape is) is hidden inside the barrel anyway. Won’t work on pencils where the knock cap has no contact with the inside of the barrel, like the Zebra Drafix 300.

[cytherian]

Yes, that can work, depending upon the design. And you’re right in that given the opening of the cap, it might actually be the tube knocking against the inside of the metal cap. Because for it to be the body… that’s a lot of play! And I don’t see that kind of movement. The cap on the Uni 05 Super is prominently stepped, and the visible part is machined to fit snugly in the body tube opening. So the cap is definitely not rattling against the body.

[Ras]

Is the cap fixed in place via contact with the tube or the body? Because if it’s the former, and the tube is rattling against the cap, that means the cap will be falling off

[cytherian]

Well, I appreciate that question because I double checked and yes–when you place the cap over the mounted eraser on the lead reservoir tube, it’s actually snug even before the cap enters inside the tube opening of the body.

So, maybe it’s a slight gap between the cap and the body after all. And my DIY actually causes the cap to seat perfectly centered as it is fully inserted into the body, thereby eliminating the rattle. I will have to go back over to one of my other examples that doesn’t have the DIY fix (it’s tucked away in a bag of random used pencils in a storage location) and do some experiments. I’m very curious as to what is the exact cause, even though my DIY solves the “problem” (slight rattling sound when you wiggle the pencil). The question is, HOW is it actually solving it.

[Ras]

Your padding around the tube probably fixed the tube perfectly in place at the center, which indirectly stopped the cap from rattling (if it was the cap that’s rattling to begin with) because the cap is fit snugly onto the tube