UKC

Hi, so I have a cheap mobile phone and bought the quad lock universal fittings to attach said phone to bike, but as I ride in the rain I bought a waterproof bag to put my phone in. I stuck the universal fittings to the back of the bag and went for a ride yesterday. The bag and fitting parted company and on getting home I read the finer details and the adhesive on the fitting will not bond to the plastic (probably TPU). Anyone got any suggestions for a suitable glue? I tried araldite 2 part epoxy and that didn't work. Thanks.

The fitting is a thermoplastic elastomer, a rubbery material?

What is the bag made of?

https://www.thistothat.com/

But, to be honest, I'd probably use releaseable cable ties.

The quad lock comes with 3M VHB adhesive tape. I made a metal plate the same size as the fitting so I can attach the fitting to the metal plate using the supplied adhesive and now need to fix the metal plate to the bag. The bag is by over-board, it does not say what it is made of. I think either polypropylene or polyurethane.

This particular adhesive is very good, even with hard to fix materials. We use it at work on aircraft components.

Also used it at home on numerous items.

Loctite 480 Rubber Toughened Instant Adhesive Black

Here is a brief description.
For applications where shock resistance is required or shock or peel loads are present
Ideal for bonding metal to metal, to rubber or magnets
Good resistance in humid environments
Service temperature range: -40 degrees to +100 degrees

https://www.henkel-adhesives.com/cl/en/product/instant-adhesives/loctite_48...

Of the cheap/readily available options I'd try something like Evostick contact adhesive next or look for a different solution.

jk

Metal to polypropylene fabric then..probably

If it is polyprop then that polymer is difficult to bond. In the past I tried bonding fabric to metal with unreliable results. In the end I resorted to rivets.

The toughened cyanoacrylate mentioned above might work if the plastic isn't polyprop but if the epoxy didn't stick then in my experience the superglue won't either. I assume the fabric separated from the glue as opposed to the glue from the metal?

The answer from the second bloke on this thread is worth reading as he explains the chemistry behind the problem but the solution is not one that will be available to you.

https://www.researchgate.net/post/A_glue_for_attaching_polypropylene_compou...

Thanks, yes the glue separated from the fabric. I was thinking about rivets as well.

could you not lash the assembly in place with whimsical but effective knautical knots?

There are many applications where I simply do not trust adhesives (and many where I do)

I hate that stuff, one of the compressor brands we work on has a 10 inch aluminium disc that has a slot machined round the outside of the face that is an interference fit with a 5mm oring and then put a bead of 480 in before the Oring.

All sounds great until you realise the Oring is a service item that needs changing once a year. 

Looking for an elegant solution, but just thought I could probably use an ortlieb spares screw set, the same they use on their bags. Have the screw head on the inside of the bag and the nut on the outside, the opposite of their usual layout, then fix to steel plate.

Not suggesting a 3d printed solution, just some design ideas, but how about these as a concept:
https://www.thingiverse.com/thing:3871391
https://www.thingiverse.com/thing:52901

If you have steel plate and the means to bend it you could knock up something like that?

Ahh the glue is too good haha.

Still got it on my fingers a few times. Is well grim!

There's no way you should be gluing in the O ring if it's being used as a seal (I realise you're just following the instructions). If it's a version of superglue (fairly sure it will be) you can dissolve it with acetone (nail varnish remover).

The most stupid thing I ever saw was an instruction to tighten up wing nuts to a specified torque. They were in a kit used to attach 6ft diameter fibreglass radomes to microwave dishes. You may not be suprised that I found out about this brilliant design after one of the radomes fell off and landed on the helideck of an oil rig.

Assuming the plate is ferrous, could maybe use magnets inside the bag to hold it fast to the plate?

My go to method of "fixing" stuff.

May the (magnetic) force be with you.

Interesting  would the magnets affect the phone especially the internal compass  when using it for directions. 

Compass yes, everything else should be fine.

jk

Mitrebond or gorilla Pu glue or CT1

I thought this was a thread about brown paper bags....

That said, I bought some good old fashioned cow gum type glue on a trip to America to fix the headlining in my boat back home. Even with the hatch open, after half hour I 'felt a bit weird' (to quote the spad) and after getting home spent the rest of the day sick as a dog. Never felt so rough, yet I'm sure as a kid we used to make blue peter toys using such stuff. Muss be turning into a wuss now.

Could you fabricate a solution using Polymorph? - it has amazing applications and is strong and quite dependable providing it isn't heated close to 62 degC

And if it isn't right first time, just put in hot water and rework it

Don't try to make a belay device out of it ....

You glue aeroplane's back together, real aeroplane's!! 

Yours Faithfully

Scared.

East Boldon

modern aircraft use a lot of composites - that was true even back in the 80s when I was at BAe

and what about the Mosquito?

Damn fine vet with a very steady hand that can glue a mosquito back together!!

The Boeing 787 is light because it is "glued" together.

Its all good... probably.

The chances are that you are trying to bond to a polyolefin. That normally does not work.

The common polyolefins are polyethylene and polypropylene. Specialist adhesives or specialist surface preparations are required for bonding to these materials. 

While working on a towed marine magnetic survey system back in 2012, I designed an instrument case for the system that was based around a Pele case. Pele cases are polyolefin and so I needed to go to my old friends at Henkel/Loctite technical support for help. They advised an adhesive developed for sticking the bumpers onto BMWs. With that, I was able to stick two bars of unplasticised PVC to the base of the Pele case into which we set brass inserts for screwing down the circuit boards, power modules and amplifiers. 

However, things will have moved on since then and you might try these folks for the latest info.
https://www.loctite-consumer.co.uk/en/meta/meta-nav/contact.html

Thanks Jim, might give that a try, loctite has come up in a number of searches and on here as well, but they do have an array of glues, so might be best to ask them.

I'd try sikaflex 291 polyurethane adhesive, it seems to stick to anything and never come off.  Might be best to find a local boat or caravan builder and scab a partially-used tube off them. - Edit - what about seam sealer? That's PU and designed to stick to fabric......

or old chewing gum?

Wooden and composite aircraft have always been glued together. In fact composite aircraft basically are 'glue'.

This was restored to airworthy by my mate. The wings were a mess but fuselage was glued together in the 30s (as is obvious from the livery), because it's been dark and dry it was largely sound. https://abpic.co.uk/pictures/model/Jacobs%20DFS%20108-70%20Olympia-Meise

jk