I have a nylon part, into which a plastic part fits. The nylon part has
a 4mm recess of around 10mm diameter and is a rather poor friction fit,
but the joint needs to be proof against DOT 4 hydraulic fluid, under no
pressure and be mechanically strong. The plastic part fits into the
nylon part by around the 4mm.

I am looking for suggestions for a suitable adhesive for the job
please.

I was thinking to cut grooves inside the nylon part and around the
diameter of the plastic part, to help the strength.

Harry Bloomfield a écrit :
I have a nylon part, into which a plastic part fits. The nylon part has a 4mm
recess of around 10mm diameter and is a rather poor friction fit, but the
joint needs to be proof against DOT 4 hydraulic fluid, under no pressure and
be mechanically strong. The plastic part fits into the nylon part by around
the 4mm.

I am looking for suggestions for a suitable adhesive for the job please.

I was thinking to cut grooves inside the nylon part and around the diameter
of the plastic part, to help the strength.

There is a photo of the parts here -
http://i455.photobucket.com/albums/q...psc1zvuve8.jpg

It is a clutch master cylinder piston, a design failure. The two parts,
tend to part company. The black plastic on the left of the nylon,
contains a fluid seal and a ball joint on the end of the push rod.

On 7/6/2016 8:24 PM, Harry Bloomfield wrote:
Harry Bloomfield a écrit :
I have a nylon part, into which a plastic part fits. The nylon part
has a 4mm recess of around 10mm diameter and is a rather poor friction
fit, but the joint needs to be proof against DOT 4 hydraulic fluid,
under no pressure and be mechanically strong. The plastic part fits
into the nylon part by around the 4mm.

I am looking for suggestions for a suitable adhesive for the job please.

I was thinking to cut grooves inside the nylon part and around the
diameter of the plastic part, to help the strength.

There is a photo of the parts here -
http://i455.photobucket.com/albums/q...psc1zvuve8.jpg


It is a clutch master cylinder piston, a design failure. The two parts,
tend to part company. The black plastic on the left of the nylon,
contains a fluid seal and a ball joint on the end of the push rod.

Link not working for me. I would think about cyanoacrylate for a start,
but it also depends on the other plastic.

The other strategy for problems like this is to look for something which
makes a mechanical bond other than in the push fit region, e.g. either a
mechanical clamp or a fillet of something like epoxy around the outside.
You might be able to use Sugru for this, I have a pack but have only
used it once (and I forget what for, for the moment).

On 06/07/2016 20:13, Harry Bloomfield wrote:
I have a nylon part, into which a plastic part fits. The nylon part has
a 4mm recess of around 10mm diameter and is a rather poor friction fit,
but the joint needs to be proof against DOT 4 hydraulic fluid, under no
pressure and be mechanically strong. The plastic part fits into the
nylon part by around the 4mm.

I am looking for suggestions for a suitable adhesive for the job please.

I was thinking to cut grooves inside the nylon part and around the
diameter of the plastic part, to help the strength.

I think I would just drill a hole through both pieces and use a pin - or
does the design of the ball joint seat prevent that?

On 06/07/16 21:15, newshound wrote:
On 7/6/2016 8:24 PM, Harry Bloomfield wrote:

The other strategy for problems like this is to look for something which
makes a mechanical bond other than in the push fit region, e.g. either a
mechanical clamp or a fillet of something like epoxy around the outside.
You might be able to use Sugru for this, I have a pack but have only
used it once (and I forget what for, for the moment).

Heatshrink?

--
Adrian C

On 06/07/16 20:24, Harry Bloomfield wrote:
Harry Bloomfield a écrit :
I have a nylon part, into which a plastic part fits. The nylon part
has a 4mm recess of around 10mm diameter and is a rather poor friction
fit, but the joint needs to be proof against DOT 4 hydraulic fluid,
under no pressure and be mechanically strong. The plastic part fits
into the nylon part by around the 4mm.

I am looking for suggestions for a suitable adhesive for the job please.

I was thinking to cut grooves inside the nylon part and around the
diameter of the plastic part, to help the strength.

There is a photo of the parts here -
http://i455.photobucket.com/albums/q...psc1zvuve8.jpg


It is a clutch master cylinder piston, a design failure. The two parts,
tend to part company. The black plastic on the left of the nylon,
contains a fluid seal and a ball joint on the end of the push rod.

spirit based contact adhesive

Photobucket never works for me at all

--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

It is very difficult to glue dis similar plastics as solvent based ones
might only melt one of them.
Also the pliability will be different if the joint is under any mechanical
loading.
This is where you need a 3D printer to make it all in one lump.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"newshound" wrote in message
...
On 7/6/2016 8:24 PM, Harry Bloomfield wrote:
Harry Bloomfield a écrit :
I have a nylon part, into which a plastic part fits. The nylon part
has a 4mm recess of around 10mm diameter and is a rather poor friction
fit, but the joint needs to be proof against DOT 4 hydraulic fluid,
under no pressure and be mechanically strong. The plastic part fits
into the nylon part by around the 4mm.

I am looking for suggestions for a suitable adhesive for the job please.

I was thinking to cut grooves inside the nylon part and around the
diameter of the plastic part, to help the strength.

There is a photo of the parts here -
http://i455.photobucket.com/albums/q...psc1zvuve8.jpg


It is a clutch master cylinder piston, a design failure. The two parts,
tend to part company. The black plastic on the left of the nylon,
contains a fluid seal and a ball joint on the end of the push rod.

Link not working for me. I would think about cyanoacrylate for a start,
but it also depends on the other plastic.

The other strategy for problems like this is to look for something which
makes a mechanical bond other than in the push fit region, e.g. either a
mechanical clamp or a fillet of something like epoxy around the outside.
You might be able to use Sugru for this, I have a pack but have only used
it once (and I forget what for, for the moment).

Lee a écrit :
On 06/07/2016 20:13, Harry Bloomfield wrote:
I have a nylon part, into which a plastic part fits. The nylon part has
a 4mm recess of around 10mm diameter and is a rather poor friction fit,
but the joint needs to be proof against DOT 4 hydraulic fluid, under no
pressure and be mechanically strong. The plastic part fits into the
nylon part by around the 4mm.

I am looking for suggestions for a suitable adhesive for the job please.

I was thinking to cut grooves inside the nylon part and around the
diameter of the plastic part, to help the strength.

I think I would just drill a hole through both pieces and use a pin - or does
the design of the ball joint seat prevent that?

There is insufficient 'meat' on the black part, where it enters the
nylon section.

Adrian Caspersz a écrit :
On 06/07/16 21:15, newshound wrote:
On 7/6/2016 8:24 PM, Harry Bloomfield wrote:

The other strategy for problems like this is to look for something which
makes a mechanical bond other than in the push fit region, e.g. either a
mechanical clamp or a fillet of something like epoxy around the outside.
You might be able to use Sugru for this, I have a pack but have only
used it once (and I forget what for, for the moment).

Heatshrink?

It is a piston sized to fit a bore, nothing can be added to the outer
diameter and heatshrink would pull straight off anyway.

Brian Gaff a écrit :
It is very difficult to glue dis similar plastics as solvent based ones might
only melt one of them.
Also the pliability will be different if the joint is under any mechanical
loading.
This is where you need a 3D printer to make it all in one lump.

Normally the joint would be under compression with fluid in the system
and connected to the clutch release system. With no pressure coming
from the clutch, there can be some tension involved in pulling the
nylon piston and seal back (to the left).

A further issue is fluid leakage through and between the nylon to black
plastic part joint. There is almost zero pressure of fluid across the
joint, but if the joint parts company all of the fluid is lost.

So I am looking for a specialised nylon/ plastic adhesive or epoxy glue
to solve the issue.

On 07/07/16 10:03, Harry Bloomfield wrote:


So I am looking for a specialised nylon/ plastic adhesive or epoxy glue
to solve the issue.

One of the benefits of making model aeroplanes, is you get to play with
just about every glue it is possible to buy.

I can tell you right away that NOTHING really sticks to nylon well, and
only two options exist here to the best of my knowledge

One I have already stated is petroleum spirit based contact adhesive
like the original Evostik. This can be peeled off nylon, but its pretty
strong in shear

The other possibility is a Loctite style thread-locker.

You might try superglue, but I have my doubts.



--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

On Thursday, 7 July 2016 10:20:58 UTC+1, The Natural Philosopher wrote:
On 07/07/16 10:03, Harry Bloomfield wrote:


So I am looking for a specialised nylon/ plastic adhesive or epoxy glue
to solve the issue.

One of the benefits of making model aeroplanes, is you get to play with
just about every glue it is possible to buy.

I can tell you right away that NOTHING really sticks to nylon well, and
only two options exist here to the best of my knowledge

One I have already stated is petroleum spirit based contact adhesive
like the original Evostik. This can be peeled off nylon, but its pretty
strong in shear

The other possibility is a Loctite style thread-locker.

You might try superglue, but I have my doubts.

I was going to suggest flaming the surfaces to enable gluing, but not for cylinder components.


NT

On 07/07/16 09:54, Harry Bloomfield wrote:
Adrian Caspersz a écrit :
On 06/07/16 21:15, newshound wrote:
On 7/6/2016 8:24 PM, Harry Bloomfield wrote:

The other strategy for problems like this is to look for something which
makes a mechanical bond other than in the push fit region, e.g. either a
mechanical clamp or a fillet of something like epoxy around the outside.
You might be able to use Sugru for this, I have a pack but have only
used it once (and I forget what for, for the moment).

Heatshrink?

It is a piston sized to fit a bore, nothing can be added to the outer
diameter and heatshrink would pull straight off anyway.

Ah, oops ...

--
Adrian C

On 07/07/16 10:51, wrote:
On Thursday, 7 July 2016 10:20:58 UTC+1, The Natural Philosopher wrote:
On 07/07/16 10:03, Harry Bloomfield wrote:


So I am looking for a specialised nylon/ plastic adhesive or epoxy glue
to solve the issue.

One of the benefits of making model aeroplanes, is you get to play with
just about every glue it is possible to buy.

I can tell you right away that NOTHING really sticks to nylon well, and
only two options exist here to the best of my knowledge

One I have already stated is petroleum spirit based contact adhesive
like the original Evostik. This can be peeled off nylon, but its pretty
strong in shear

The other possibility is a Loctite style thread-locker.

You might try superglue, but I have my doubts.

I was going to suggest flaming the surfaces to enable gluing, but not for cylinder components.


NT

Actually little research reveals that you can rough up NYLON with
acetone, I was thinking of polythene


--
Future generations will wonder in bemused amazement that the early
twenty-first centurys developed world went into hysterical panic over a
globally average temperature increase of a few tenths of a degree, and,
on the basis of gross exaggerations of highly uncertain computer
projections combined into implausible chains of inference, proceeded to
contemplate a rollback of the industrial age.

Richard Lindzen