Ok - Adhesive Experts...

[markh]

I have a Morrison bchr pen with bright red ends. I presume these are casein/galalith. One end is detached.

 

I tried gluing with shellac, but it didn't hold. I could try this again. Or I could use epoxy - but I hate to use this with a vintage pen as it's so permanent.

 

Any suggestions for an intermediate glue - stronger (and maybe thicker) than shellac, but not as final as epoxy??

 

thx.

 

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[mitto]

In my experience even the epoxy wouldn't work in gluing hard rubber. Let us hope someone else chime in with a solution.

[Chrissy]

I think epoxy is the only way to go. Your decision is: either you want it glued on or you don't.

 

Shellac won't do the job nor will "superglue" I can't see anything else working. It must have been designed to be permanently attached.

[markh]

Hmmm... that gets me thinking - Loctite 380/480. It's cyanoacrylate (super glue) compounded with rubber - black instead of clear. Supposed to stick rubber.

 

The problem with that stuff is that a bottle is expensive, you use a few drops, and by the next time you need it it's hard as a rock. Might give that a try - have some in the fridge that might still be good.

 

I never want to glue anything on a vintage pen that can't be undone, maybe 80 years from now (like I'm fixing this pen 80 or so years after it was first made.) But I guess in this case there is no choice.

 

 

 

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[CS388]

Hmmm... that gets me thinking - Loctite 380/480. It's cyanoacrylate (super glue) compounded with rubber - black instead of clear. Supposed to stick rubber.

 

 

Yeah, if it's a BHR pen, I'd try that.

 

We always have to realise that we risk wrecking the whole pen, at times like this - but it sounds like you're on top of that.

Let us know how you get on - and try to post a picture, sounds like an interesting pen.

 

Good luck.

[fountainpagan]

BCHR = hard rubber pens, not galalith/casein (milk protein treated as a polymer).

 

I agree with markh.

[markh]

BCHR = hard rubber pens, not galalith/casein (milk protein treated as a polymer).

 

I agree with markh.

 

The pen is BCHR. The red ends (decorative tips) on both ends I'm pretty sure are casein. The one on the cap is unstuck.

 

So I need to stick casein to rubber. Probably difficult on both sides.

 

 

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[Ron Z]

I started to answer this when I got interrupted by a call.

 

I am always cautious with casein. I never know exactly how materials will respond. I would not use super glue, and would be hesitant with epoxy, though that may work. It may well be that the original adhesive was mucilage, though we never think of using it today.

 

The question is whether the connection is a butt joint, or whether part of the button goes into the end of the barrel so that you have a bit of a lap joint. If the former, things are a bit more difficult.

 

A common adhesive that I have used with casein in the past is wood glue. If a simple butt joint (disc on the end, vs a nipple that fits into the barrel) it may be difficult to get things to stick. A lap joint provides more contact area, so would hold better. I would suggest trying wood glue, or maybe a waterproof wood glue. Clamp together, or hold the disc in place with black electrical tape. I like Scotch 33+ because it stretches and pulls the parts together. Let it set over night before "testing" the repair.

[pen2paper]

non-expert inquiry.. is there an adhesive that bonds safely to casein, another to HR, and a third that bonds the two? perhaps by UV?

[EMQG]

OP, what makes you think it's casein?

[markh]

OP, what makes you think it's casein?

 

1. The pen was made in an era where the plastic choices were hard rubber, casein, maybe bakelite. I don't think celluloid had been used at that time.

2. It has a slight (very slight) transparency that reminds me of other casein pens.

3. I've seen other similar bchr pens with red ends, and people who I think knew what they were talking about identified the material as casein.

 

So.. I think it's a reasonable guess.

 

The end was glued in with Loctite 380, a formula compounded with rubber, and designed to stick to rubber. I've had luck with a similar adhesive - Loctite 480 - before. So far the glue is holding.

 

The problem with this glue is that a bottle is almost $30. I don't use it very often.

I use one drop, and by the time I need it again it's hardened. I have the empty space in the bottle above the glue filled with Bloxygen, and keep it refrigerated, in the hope that it will last a while.

 

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[Ron Z]

I would be interested in seeing if that actually works. One of the methods for curing CA glues where you can't apply pressure to get it to polymerize is to use an activator, which I understand is an oxygen deprivator. Bloxygen is argon gas - a dry inert gas which is used to displace the air to prevent oxidation of the material. I wonder if that could have the same effect as the CA activators.

 

BTW, Black Max is available in 3 gram tubes for about $4.50

[markh]

I would be interested in seeing if that actually works. One of the methods for curing CA glues where you can't apply pressure to get it to polymerize is to use an activator, which I understand is an oxygen deprivator. Bloxygen is argon gas - a dry inert gas which is used to displace the air to prevent oxidation of the material. I wonder if that could have the same effect as the CA activators.

 

BTW, Black Max is available in 3 gram tubes for about $4.50

 

 

It was pressured (or at least held close) with that old standby, blue tape.

So far the part is holding.

 

As to Black Max - apparently the same stuff. I see it for $8. at Amazon. Where is it $4.50?

At that price I can use it once, and if it hardens I won't feel bad about it.

 

 

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