Teflon Paste For Eyedroppers

[dipper]

On 1/23/2023 at 5:59 AM, BrassRatt said:

On 1/21/2023 at 7:15 PM, Trnsncdr said:

... Teflon is NOT particulate unless it has dried. It is a misunderstood lubricant. 

I have to question this.  Is the Teflon actually in solution?  In what state is the Teflon, not particulate, in the grease? Is there some other way for a flowable solid not to be particulate? 

I have been puzzling over this also.

Whilst waiting for more details from @Trnsncdr I can suggest some pieces of information.

There is something here worth finding out about for possible use in pens.

 

Though we can imagine a paste or milky fluid composed of small particles of finely ground solid plastic suspended in water, such a material would not become a "solid when dried". It would become simply a dusty heap of plastic grit.

In contrast to the (mistaken?) idea above, during the chemical manufacturing processes used to create a plastic polymer those reaction processes can take place in an aqueous medium - and the plastic "particles" produced can be "small" down at the molecular scale. (Much smaller than any particles made by physically grinding up pieces of solid plastic.)

Such a material is a "colloidal dispersion" and can be stable until the water evaporates - when the molecular scale polymer "particles" can then spontaneously join together into longer polymer chains.

Such a material is common household PVA glue, or white glue, or Acrylic Paint.

 

I was unaware that such a thing was possible with PTFE polymer (aka "Teflon").

But searching for "PTFE dispersion" immediately proved me wrong..

https://www.solvay.com/en/brands/algoflon-ptfe/dispersions

 

So it seems that PTFE/Teflon is available, somewhere, in a physical form not unlike PVA household glue.

I am guessing that when dry it may form a layer of solid PTFE, or linked strands of PTFE within a fabric (the manufacturer's web pages talk about uses in treatment of fabrics).

But then if mixed with grease, as in a tub of bicycle grease labelled "with Teflon" that I have sitting in the garage now, it never would be able to "dry" and complete the linkage of the molecular size PTFE particles.

 

So now I want to find out what the properties are of the substance mentioned by @Trnsncdr.

Is it a "better" sort of grease, or can it be used to lay down a coating of solid PTFE by painting onto the threads of an eyedropper pen and waiting for the water content to dry?

 

And .... can I buy some? 

 

 

Note:

There is another currently active topic in this forum that may have some overlap with this PTFE topic. "Montblanc pink sealant". It's pink, it's fluid, and it dries to become a rubbery non-sticky solid. Perhaps that is just colored latex though?

 

[BrassRatt]

22 hours ago, dipper said:

...

But searching for "PTFE dispersion" immediately proved me wrong..

https://www.solvay.com/en/brands/algoflon-ptfe/dispersions

...

And .... can I buy some? 

Often, specialty materials like that are offered in sample quantities (more than fountain-pen size) if you are politely convincing about a mere potential for future purchases.  When I worked in research labs I got some amazing stuff that way.  

[dipper]

Have found some PTFE thread sealant liquid!

In fact, found lots of different brands.

 

This sudden appearance on my radar is a weird Alice In Wonderland moment. (The product is not new to the market. One of the retail suppliers linked below says that the product ".... has been used for years ...". And this forum topic was started in 2013.)

 

https://www.toolstation.com/tru-blu-pipe-thread-sealant/p40236#full-desc

 

https://www.screwfix.com/p/flomasta-ptfe-liquid-50g/5321j

 

https://www.wickes.co.uk/LA-CO-Slic-Tite-Heavy-Duty-Pipe-Thread-Compound-Sealant-with-PTFE---240ml/p/227184

 

The role played by PTFE in these various brand compounds is unclear from the pages linked above. Perhaps the chemistry does not really matter though.

The user reviews in the links above, posted by plumbers mainly, do reveal lots of clues about the physical properties.

 

The OP question remains unanswered. Has anybody tried the materials, as linked above, in eyedropper pens as a sealant or gasket?

 

 

 

 

 

[JCC123]

So, Montblanc uses the bubble gum sealant on the nib side and a clear gummy type on the rear in the piston side. I was trying to figure out what this sealant resembled to me? What I thought was that it most resembles the credit card glue. You know, the gummy, sticky stuff that sticks to the back of the credit card when they send it to you in the mail?

 

I quick search on Google and I found this: booger glue

 

The low tacky version should work as it's not destructive and is easily removed, just like the Montblanc version. Although this might not be waterproof.

[dipper]

On 1/24/2013 at 9:55 PM, theoneanalog said:

Does anybody have experience with using Teflon paste (TFE paste) to seal eyedropper threads? ..... snip........ this stuff is designed for pipe threads so I imagine it's safe but want to be sure.

 

After some testing, the short answer is - no, the stuff designed for pipe threads is not suitable.

 

But there are so many different products that have "Teflon" or PTFE in their name that a longer answer is needed, if only to sort out what product types we are talking about.

 

We find PTFE in its solid form in many places..

... including white PTFE tape, that is useful with some pen threads. (Easily removable, helps tighten loose floppy threads, but risks cracking the pen parts if applied too thickly.)

 

And we find solid PTFE in the form of a fine talc-like powder mixed into some lubricants..

In these forms the PTFE particles assist the lubricating properties of the product.

 

And there is a third type of product where the PTFE molecules are held in a state where they have not yet joined together into long polymer chains. After some "curing" process they can join together to become a solid. That process is not reversible. Useful for sealing pipe threads and other purposes.

... This Flomasta product is the one I have been testing. It is a viscous blue fluid - as seen in the two blobs on a piece of scrap brass in the photo above.

Other brands are labelled as "paste". Assumed to work in a similar way, if sold as pipe thread sealant, but not tested here.

 

Below are some of the test pieces being prepared ...

Pictured above are, a blob laid onto black PTFE sheet and sealed with sticky tape.

Various metal screw threads and washers, nuts about to be screwed over the blobs of liquid.

A Platinum Preppy, assembled and the joint wrapped with sticky tape to exclude air.

And two blobs squished between two metal plates.

 

The instructions on the bottle say that the product "cures" when in a narrow gap with air excluded. Time to cure 3 hours to 3 days, depending on materials being sealed.

So all my test pieces were left for three days in a warm place to cure (or not).

 

Results:

 

Applied to metal threads...

Excellent! The threads were impossible to undo by fingers alone. Easily undone using a spanner. The sealant had fully solidified inside the threads. When undone with a spanner the solid PTFE broke up into dry crumbs.

Beads of liquid at edges still open to the air (not inside the threads, or not on internal faces of washers) had become a sticky gum.

So this use is ideal for domestic plumbing work, where joints are not intended to be undone.

 

Applied to plastics

Failure!

The blob that was sealed between a PTFE sheet and sticky tape did not cure. It did go a bit thicker, and very sticky. Very difficult to remove!

 

The PTFE liquid in the Preppy was similar. Not cured, just a bit thicker, very sticky, and very difficult to clean off.

Also the liquid had reacted with the Preppy plastic, softening the surface of the plastic.

(I did clean off the gunk, with some Preppy material being lost in the process. Then polished the erroded area with metal polish.)

 

Squished between two metal plates....

Here the liquid blobs did cure fully, except for a few beads that squeezed out at the edges.

Unlike the metal threads, in this test I was able to separate the two metal plates without sliding. Using two spanners the plates cracked apart, revealing two discs of solid hard blue PTFE plastic bonded to one or other of the plates. (Shown at bottom right of the picture above.)

I seem to have made a miniature non-stick frying pan!

Thickness of the solid PTFE coating formed measured 0.05mm to 0.20mm.

 

From all the results above I can visualise a use in sealing eyedropper threads, but have not tested how this could be achieved in practice .... 

For metal threads, if the PTFE liquid could be persuaded to bond to one threaded part only, and then the other part could be unscrewed without destroying the solid PTFE, we could make perfectly mating threads. Similar to a wrap of PTFE tape, but permanent, and with no pen body cracking risks.

Perhaps clean one thread to make its surface very reactive (rub with wirewool?) and coat the other thread with silicone grease?

I might try that with some nuts and bolts. But would need to be 100% certain of success before risking it on a pen. If one trace of PTFE becomes bonded to both threads then the result could be disastrous.

[BrassRatt]

Except for the claims of PTFE content, of course, that blue stuff sure sounds like Loctite 242 Anaerobic Threadlocker.  And the "Contains:" line shows the acrylics that actually do the anaerobic curing.  

 

Since it crumbles rather than smoothly sliding apart, I wonder what the PTFE in the name really signifies. 

 

 

[FarmBoy]

I wonder what Ron thinks about using all these Teflon things on pens.

[Ron Z]

27 minutes ago, FarmBoy said:

I wonder what Ron thinks about using all these Teflon things on pens.

 

Setting out bait is unfair. 

 

Politeness prevents me from using the verbage I'd like to use.  But I would not, do not use any Teflon products on my pens.  Teflon tape is for pipes.  It fills and puts some outward pressure on plastic parts.  I prefer not to take the risk of something cracking - and I have seen it happen.  It's also a pain in the tush to get out of the threads. 

 

We don't know what else is in the teflon compounds that may or may not harm plastics, especially celluloid.  I have a great deal of respect for the vulnerability of celluloid to chemical reactions that can destroy the pen.  I've seen Celluloid crumble over night from contact with something it doesn't like.  

 

For threads like Vac section threads etc. I  use a rosin based sealant.  The fact that it is sticky means that not only do you get a good seal, but you do not need to tighten the joint past snug to make sure that it will not come apart again.  I use it on Vac jewels etc. as a safe thread locking compound.  I do not find the modest heat (under 100F) needed to release it to be a problem. 

 

No, rosin based thread sealant is not an adhesive.  It has no shear strength, no adhesive properties.  It's just sticky, and fills the gap in the threads. 

 

re. the Montblanc "bubblegum".  That is a silicone rubber compound with a low shear strength.  It may be an RTV silicone, in which case you want to make sure that it is low shear strength material so that it will come loose fairly easily.  The stuff from the hardware store is an adhesive. It sticks, it does not shear easily.  The MB stuff may also be a two part silicone rubber compound.  I don't know.  A product support tech at Loctite and I had a conversation a number of years ago about this, and he told me it could be either - and that they have access to compounds in Europe that we can not get here in the USA.

 

But Teflon products, especially lubricants and pipe dope?  No.  Never.

 

[dipper]

5 hours ago, Ron Z said:

But Teflon products, especially lubricants and pipe dope?  No.  Never.

I fully agree with that.

 

The purpose of my experiments was to find out what the stuff "for pipes" actually is.

I think that I do understand that now.

It is a rigid thread sealant intended for metal pipe fitting threads used in plumbing installation, and for similar pipes carrying other fluids including some gasses.

In that specific field of use it does have advantages over PTFE tape.

 

The physical properties of the cured material are interesting to know. (As described in my post above.)

 

Trying to invent some possible use for the product in fountain pen related work... my conclusion was that it is neither possible nor safe to even attempt.

(Hence my choice of a Preppy and not Pelikan to try a test.)

[Ron Z]

I'm glad to see you writing that!  If you knew what I run into when I repair pens, you'd understand the .