Any Alternatives To Montblanc Bubble Gum Sealant

[JCC123]

9 hours ago, Dione said:

As far as I know Montblanc only use sealant on the nib collar, not on the piston. I've unscrewed a piston with a piston tool bought on ebay. The main points are to not forget to screw down the cone next to  the tool before turning the tool so the tool doesn't slip out and gouge your pen and working out a way of getting the piston back in so that you can fill it with somewhere near the original amount of ink.

2 hours ago, Ron Z said:

The seal at the piston end is the piston seal....  Nothing is used on the threads to seal.  Indeed, to try would be futile since the spindle and grip knob have to be free to move, so if enough ink got past the piston seal it would leak through the thread bushing and out around the grip knob.  When we see ink there, it's a sure sign that the piston seal is failing or has failed.

 

The stiff grip knob is  caused by a dry piston seal, which should be lubricated. The discussion of which will open up a whole different can of worms.

 

Thanks guys, I thought that it wasn't sealed on the piston side threads but I just wanted to double check. The knob on mine has always been really tough to rotate. Now, I need to find some quality silicon grease and a wrench. I see that someone on Youtube used a paperclip. Hmmm...

[JCC123]

Opps, hey guys I just opened and lubed my pen and it looks like Montblanc did indeed seal the piston side as well. On my pen, a 146 Plat which I bought new back in 2000, had what looks like a form of rubber cement. It mostly resembles the kind of soft silicone/rubber that you find attaching new credit cards you receive in the mail. I've attached a photo of the threads with the glue still on it. I think they probably thought that the seal would prevent water from getting through when you washed your pen. I've left the remaining glue residue on my threads when I closed it hoping that it's enough to reseal it.

 

 

[JCC123]

Now, doing a bit more research, I noticed that silicone grease will destroy silicone parts. I was wondering could my plunger be made of silicone and not rubber? Does anyone know if Montblanc ever used silicone plungers? The plunger of my pen is translucent white which makes it appear like it's silicone? Could that explain why the inside of my pen was completely devoid of any silicon grease? My plunger was clean with not a hint of grease even being on it.

 

I'm just nervous that the reason is that it's made of silicone and is made to work without grease?

[Ron Z]

That would be a thread lock compound, to keep the thread bushing from unscrewing too easily.

 

The lubricant can wash out over time.  It's quite common on piston fillers.

 

The piston seal is plastic, not silicone. There is discussion about using silicone grease or Vaseline, hence my comment earlier in the thread.  I'm on the side of silicone grease, following the comments from one of the best MB repair guys around.   A good silicone grease (Like Molykote 111) is designed to work with most polymers, and also resists washing off.  That's what I both use and sell.

[JCC123]

2 hours ago, Ron Z said:

That would be a thread lock compound, to keep the thread bushing from unscrewing too easily.

 

The lubricant can wash out over time.  It's quite common on piston fillers.

 

The piston seal is plastic, not silicone. There is discussion about using silicone grease or Vaseline, hence my comment earlier in the thread.  I'm on the side of silicone grease, following the comments from one of the best MB repair guys around. 

Thanks Ron, I would use whatever Montblanc uses since they would know best. I think they use silicone?

 

One other question, when I pulled out the plunger, the gasket looks to be in reverse of what I see on other Montblancs. Mine had the wider diameter towards the back and not the front. Any idea if that's correct and how mine ended up with it like that? Thanks.

[Ron Z]

Montblanc uses a form of silicone rubber.  Important characteristics include a low shear strength and low adhesion.  Use regular RTV silicone cement and you'll never get the nib unit out without breaking something.

 

MB changed their design somewhere along the way.  Not sure when, but that is in there works. 

[JCC123]

Thanks Ron, I meant that I would use silicone grease and not Vaseline if that's what Montblanc uses. Does Montblanc use something proprietary there as well thus the confusion as to which to use?

 

I also noticed that certain parts inside Montblancs, like the ballpoint, have a very sticky coating. Not sure what that's for?

[Ron Z]

Part B - sticky inside.  No idea.

 

Vaseline VS silicone.   The argument is based on MB at one point saying that cracks that appeared barrels, may have been caused by silicone grease.    But it's a big "if." OTOH, most of the people that I've talked to who work on them a lot use silicone grease.  I've never seen any problems with silicone grease in a MB barrel in the 20 or so years I've worked on them, and neither has anyone else.  The Molykote statement about "safe with most..." is IMO lawyer speak, i.e. vague allowing room for something that they haven't encountered. 

 

I asked a friend who is head of the Chemistry department at the local college about silicone and plastics, Montblancs in particular.  This is his response (used with permission):

 

Silicones in general do not interact much with other polymers or rubbers. They are chemically dissimilar and therefore do not (usually) soften or dissolve in them. So, for your Montblanc pen resin, I would not expect that the Molykote 111 would react with it or soften it.

[JCC123]

Ron, so no one knows what Montblanc is using? I would have thought that they are using silicone grease as the stuff I felt sure does feel like it.

 

As for the sticky coating, I think it may have something to do with the way that the ballpoint twist mechanism needs something very viscous in order to keep it rotating slowly. If you twist the ballpoint to lower and raise the ballpoint, you can feel that there's a lot of resistance in the action. I think in addition to the mechanism itself, they add some sort of sticky viscous substance in order to obtain that smooth, slow rotating feel.

[Ron Z]

Could be.  Companies to all kinds of things (flummery) to get the right "feel."   I did audio repair back in the 80s.  There was a stereo manufacturer that glued pieces of marble into the chassis to make it feel more substantial.  You can't make this up.  A "good" stereo had a big transformer and a solid chassis = more weight, so they made it heavy.

[niksch]

 

On 2/8/2014 at 8:45 AM, rsilver000 said:

AAHH as a beekeeper, all I can say is use lots and lots of beeswax. Keep us in business. Actually if you have a local beekeeper, talk to them, We get oodles of wax every time we open up a hive. You really only need a small bit for what you want to do. Old wax is dark and new wax that will be from around areas of new comb development will be light yellow. Get the new wax.

 

 

Why is that?