I've got a kg of EL80 and I've been having a little play with some offcuts of cloth to see how it cures.  One thing I did notice is that its fairly viscous.  Is it OK to warm it a touch to thin it down a bit?

Would a review of my test pieces be of use?  If so I'd appreciate a few pointers of what people woould like to see.

Dont worry, I've had a play and answered my own question.  Yes you can stand the mixing cup in warm water to thin it a touch.  It does go incredibly thick as the temp drops!

Hi, yes, you're dead-right. The EF80 does start off life pretty thick but this viscosity (as with all epoxies) can be lowered by warming it, if necessary.

Let us know how you get on with it!

--Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales

Will do.  Its certainly interesting stuff.

Right, hopefully this will be a reasonably comprehensive look. 

The resin itself is fairly easy mixing.  It doesn't hold air too badly and is a pleasant pale golden colour.  It does have an amine smell so ventilation is needed.  Its fairly thick compared to EL2.  I found its viscosity to be quite sensitive to heat.  I warmed it and it thins down reasonably.  Laying it into a cold mold and I found it thickened up to near bonding epoxy consistency and would not penetrate fabric!  Workshop heater went on after that!.  The texture of the cured test pieces is like soft-touch buttons on remotes or in cars.  Its quite strange.  It looks smooth / shiney but is quite grippy to the touch.

I made up a few trial pieces with some offcuts of 600g twill.  2 layers is very flexible.  Bending it right round causes bulges on the fabric tow but it restores flat when you release it.  3 layers is similar but slightly stiffer (as you'd expect).  This piece highlighted the effect of weave orientation.  All 3 layers were aligned and the piece twists remarkable easy.  This is like bending at 45 deg to the weave.  5 layers is very rigid but with a very slight bendability.  Its more of a tough laminate at this thickness.  This same toughness can be achieved by laying the cloth at 45 deg rotations.  This results in a tough rather than flexible laminate.  The finished piece is sandable but I've not attacked it with the polisher yet to see if it polishes. 

My first part is a splitter for my waggon.  This was made in an open mold as I wasn't too stressed about weight and its a flexible resin.  The viscosity gave me a little issue with the surface and I have the odd small bubble / pin hole in it (should be fillable).  The part required a rigid centre with flexible edge so I keyed the back and laid in a layer with EL2.  It took the key and bonded to EL2 just fine.  This was finished with a second flexible layer over the top.  Again an easy enough bond was made.  The finished part has that strange plasticy smell I associate with Toys R us.  I'm sure that will subside as it reaches full cure.  The part is suitably rigid in the centre and flexible at the edges.  Its more of a toughness than a rubbery nature to the finished part.

It will be interesting to see how the finished part wears / weathers when in use.

thanks for that information! could you add some pictures to show how it bends and how it looks?

Matthieu Libeert
Founder MAT2 Composites X Sports
website: www.mat2composites.com

Will do.  Sorry I'ma bit late replying, I've been away for a wee while.

Again sorry for the late reply.  Body grew an extra bit and not something useful like an extra arm!  Anyway, here's a pic of the bulging tow.



I suspect this to be operator error.  This was a quick try of 2x600g layed up wet on a piece of bag film.  Very rough and ready. I may have wanted to see how flexible it was before properly cured.  It has also had a few people having a bend of it so I might have knackered its mechanical properties.  My first molding with it has come out OK.  The finish is as-per the mold like any other epoxy.  This had a post cure but I did notice additional cure over the next week or two which surprised me.  The molding is now as you'd expect with a reasonable amount of flexibility.  Its not uber flexible so think of it as tough rather than floppy.  Ideal for the car splitter I made.

Hope this helps

Hi FLD,

Thanks for the picture; it sound look like the 'bulging tow' has been caused by being flexed when not fully cured. It appears that some of the carbon tows have been able to break free of the matrix and then not bedded back down afterwards (which is not a huge surprise if the resin was mostly cured by then). Once it's properly cured you should not be able to do anything like this - we have samples that get mauled quite a bit as demonstration pieces and they hold up well. Thank you for the post and I look forward to hearing how the part performs in use.

All the best, Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales

I completely agree.  Operator error!  I was too keen to see how flexible it was.  My splitter has come out just fine.  I'll post up some pics of the final piece later.