adhesive for nylon 6

[livehho]

Hi experts,

Here's the scenario.

- I need to glue together four panels of nylon (forming a box).
- After glued they will be submerged in water for the rest of their life.
- The water will contain electrolyte (KOH - Potassium Hydroxide)
- The operating temperature of the water will be around 180° F (max 200° F)
- The nylon will surround several stainless steel plates

As you may have guessed, this is for an HHO Generator (electrolysis).

in short:

- adhesive should be waterproof
- adhesive should resist high temperatures

What do you suggest? Any special brand?

Thanks,

 

[patprimmer]

First off am reluctant to be involved in any way with snake oil like so called HHO generators. Electrolysis of water produces H2 and O2 not HHO

Formic acid is best.

Superglue might work if the load is low and the joint design is good.

Why not just buy a box from an electrical supply house. They make a wide range of boxes from PVC which should have the chemical stability you require. Temperature resistance will be marginal.

If you need higher temp than PVC, try to find a PP box or just cast one from polyester or epoxy or lay up one fro figreglass reinforced polyester.

Regards

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[livehho]

Hi Pat,

How and where would I apply the formic acid?

Thanks,

 

[CoryPad]

I would think that welding would be better for this application.

Regards,

Cory

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[patprimmer]

Umm to the surfaces to be joined.

Dip the edge of the nylon in until it softens a bit then press the surfaces together.

Welding nylon normally requires expensive tooling but will do a good job.

The plastic inline fuel filters commonly fitted to cars in the 80s were 2 nylon half shells welded ogether at the centre flange with formic acid.

It is to long a time since I did it, but I think a fillet can be built by dissolving some scraps of nylon in the formic acid to make a syrup or paste, then laying it in the corners. Use concentrated formic acid. 90% concentrated should do. Be careful it is corrosive and has noxious fumes.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Demon3]

I would not choose to use nylon in warm, alkaline water as it will get attacked by the KOH. As Pat said, but a premade box of some chemical resistant polymer like PP.

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