Why does Araldite (epoxy resin)

  Quickbeam 16:24 05 Feb 2019

...take so long to go hard now?

It used to go hard within 10 minutes at room temperature, 12 hours for a full curing.

The last few time I've mixed it, 50/50, it remains tacky for a few hours. At the mo I've got 2 plastic parts held under tension with tie wraps. I used to just have to hold it for a few minutes.

This is not just a one of pair of tubes that might be wrong, for the last 3 years I've noticed that it now takes 24 hours to cure.

  Quickbeam 20:45 05 Feb 2019

I've since discovered that I have standard Araldite and there is a rapid one. In the past it must all have been rapid as it always set quickly.

  Aitchbee 21:31 05 Feb 2019

Off subject slightly but back in the day when I started off working with BT, it was one of my jobs [ as a mere apprentice ] to mix up substantial amounts of Epoxy Putty by hand [wearing plastic gloves] ... it was used to seal off large cable joint enclosures. I recall it was beneficial to apply some Bostik to the surfaces of the prepared cable sheaths and sleeve closures etc beforehand to make a better seal ... belts 'n' braces. Epoxy plumbing course was a 2 weeks' stay in Edinburgh!

  qwbos 01:06 06 Feb 2019

Just checking my stock of aging Araldite against the website. Standard is still blue and rapid is still red. Standard supposedly gives a better long term bond but keeping components correctly aligned and under compression for 14 hours can be difficult. Parcelling with sticky tape can be quite effective.

Aitchbee

Many years ago, I upset the cleaners at work with a well placed Bicaseal poo. Very versatile stuff!

  KEITH 1955 12:12 06 Feb 2019

Quick setting glues need to change the wording on the packaging , I used to build radio controlled planes , you could and still can buy 2 part epoxy glues that allegedly "set" in 30 mins , 1 hour or a couple of hours but they are playing with the true.

Take for example " sets in 30 mins " , it does not.

What actually happens is the outer skin of the glue sets in 30 mins to allow you to carry on working , it you cut the joint in half it will still be liquid in the middle.

What is Markdown?

Markdown lets you add more formatting to your post. Simply type in your post and it will display as written.

If you wish to add bold or italic characters, add a hyperlink to another website, a heading or a horizontal line, simply use the relevent icons above the text input field.

A preview of your post will appear in the grey box below. If you make a change and you're not happy, simply press the back arrow icon to undo.

Post a Reply

4500

Elsewhere on IDG sites

Best Camera Phones 2019

How can good design help millennials fall in love?

iMac 27in (2019) review

Comment identifier le modèle de son iPad ?