Adhesives

Nigel Ramsay · Post by **Nigel Ramsay** » Wed Jul 29, 2009 5:48 pm

Ron,
Shadows and Streak shadows use plywood, aluminium, carbon fibre etc and blue foam in their construction, Araldite 2000 was used for all these bonds. Bonding wood to aluminium, aluminium to aluminium, required pre-treatment with a filthy brown fluid called acomet. The warning label suggested it could cause birth defects etc... FWIW.

mike newall · Post by **mike newall** » Fri Jul 31, 2009 4:26 pm

We have used West Epoxy for the last 10 years for all sorts of stuff - wood structure ( the One Design is all glued with this stuff ), metal, plastic, all sorts.

It is brilliant at most all things - either raw or with fibres in it almost glues spit to water at a pinch. It will even stick to plastics used in things like wheelbarrows, lawnmowers etc.

Really easy to use - use the pumps, add some fibre or micro if needed and get sticking. Good open time, cures overnight.

Richard Boyton · Post by **Richard Boyton** » Sat Aug 01, 2009 6:57 am

Have used West System for years in boat building/repair and hadn't appreciated it could be used/approved in a/c construction.

Bearing in mind its gap filling capabilities, shame we can't use it in a/c repairs where the structure had used Aerolite or Aerodux.

Or can we.?

Shame we haven't got an online reference library to access this sort of info

Richard

ColinC · Post by **ColinC** » Sun Aug 02, 2009 9:30 am

Moving off topic a bit but the use of West epoxy intrigues me too.

Everything I have read seems to suggest that the LAA allows only Aerodux and Aerolite for wooden structures but I am very sure that the Minimax builders use West Epoxy and it is specified in the design, I think its gap filling and fillet forming nature have something to do with it. Clearly epoxy is used a lot in the USA.

mike newall · Post by **mike newall** » Sun Aug 02, 2009 10:55 pm

West is used for all sorts of applications. The only thing the LAA LAA lot don't like is where it is used in a spar and then painted anything else other than white.......

The One Design is all glued together with West - specified in the plans and where it is designed, it is good for +9/-6g.

Plenty of coloured/colored ones in the States that haven't fallen to bits yet.

Shame - our air must be different as it is downgraded to +6/-3g over here, but not on the continent

jamie_duff · Post by **jamie_duff** » Mon Aug 03, 2009 3:30 pm

That must be a bit like the Glasair adhesives too then. Did anyone else spot a certain irony about the recent LAA mag feature on a Glasair III, mentioning in one breath the spectacular aerobatic displays done by Bob Herendeen in the US southern states, then in the next saying it wasn't strong enough to do aerobatics in the UK due to insufficient safety factors in warm weather?

Ian Melville · Post by **Ian Melville** » Mon Aug 03, 2009 7:07 pm

Time --- we all use the same seconds / minutes/ hours but we cannot even agree on thatwhen we are in the same time zones,

Ah, but we cannot agree on the display format

This now leads me to believe that the problem lies in the incorrect use uf conversion tables from "foreign" aircraft designs to the UK standard. Maybe it requires better education of design engineers so that they do not get confused when doing calculations and then they may realise that the UK is not really any different to the rest of the World

CS-23 is supposed to be based on FAR23 but I have been told there is some element of 'Lost in Translation'. It is this, and other design regulations that constrain designers, not thier inability to do sums.

Richard Boyton · Post by **Richard Boyton** » Tue Aug 04, 2009 5:36 pm

Having used the West Sysyem and others like it in boats for over 20 years, I would be intrigued to know from Engineering what may be the problems with Epoxy glues on wooden structures

I do understand that heat (and great heat at that) can weaken the joint, as I have sucessfully unglued joints by the use of a heat gun, but believe me you need some considerable heat, time and some skill

Could perhaps understand if we were talking about an epoxy structure left in the Arizona or Australian sun, but in the rain in the UK?

Incidentally, have joints unprotected and exposed to UV which "appear" to have lost no strength when tested to destruction on my yacht's tender

Would be interesting and useful if Engineering could respond/reply to these technical questions and even better could we not have a technical database available to all for these sorts of queries?