Which resin to use
 

Ok I am getting ready to make a mould from a plug and then the subsequent part and am looking for recommendations for which epoxy resin to use..... I have experience of using the West Systems epoxy resin and hardeners previously and have had no problems..... i have also looked at the specs for the Axson Technologies Epolam 2017 resin which is a bit cheaper..... also which surface /tooling resins are people using? Your thoughts and advice gratefully received..... i do live in the UK so I do need to be able to source it over here ....... thanks in advance Phil

I have found MGS Epoxy out of Germany to be best to lay up with. The only down side is the price, but it wets out better than anything I've used.

If you can get west systems, then you can get Pro Set epoxy, which are both made by the same company. The pro set is better and has all the qualities of the MGS and other big names. It's not far off in cost either. These next tier epoxies really set up way better and much stiffer. Very, very predictable set times... Used both and know for sure.

My Name is Ed Smith. I live in Canada.
For many, many years now I have used MGS Epoxy resin. T have used it for making molds and for making the glass parts. Fuselages and associated parts. Propellers and anything else that was a glass fibre product.
MGS Resin is a German product. I is made by Hexion Specialty Chemicals.
Stuttgart GmbH,
Am Ostkai 21/22
D-70327, Stuttgart
Germany.
At least it was the last time I used it some time ago.It never let me down.

Regards, Ed Smith.

I agree. The MGS resins are king. Not cheap, but nothing of quality is. This would probably be my first choice.

Scott

I have to give West Systems a 2 thumbs up. I have some that has been on the shelf for over a year now since the last time I used it, and other than the hardener being darker, it still worked perfectly.

I have never been a fan of West Systems resins, They are fairly expensive and their performance is very poor compared to other resin systems I have used. If you like them then go for it, but for my money I can do much better.

Scott

I've used the West systems and the Pro Set (both from same parent company) and there is a marked difference between the two. System 3 also seems to be pretty good and pretty consistent. The West systems seemed to just not harden as much as the others and may have a lower temperature tolerance, I don't know - I think I remember something to that effect. Anyway - for general purpose use, the West system isn't bad and easily available, but for something more critical, I'd probably spring for the extra.

Having said all the above - I want to try a Vinyl Esther resin for building a mold so I can use typical gel coat tooling, etc. and not cost as much, if nothing just for kicks and the education of it all. It seems to have promise.

The West Systems when mixed with Colloidal and graphite made pretty hard molds, the parts were softer when they came out, but firmed up over time. When it comes to cowls I tend to like them to be flexible so they dont crack like the ones that come with ARF. I have 3 molds I made and they are all hard as rocks. IF there is a less expensive Epoxy that is just as good or better I'm all for it, but the West Systems is easy to obtain for me. I made a mold once using automotive resin. Man was that a mistake, it melted the plug and stunk up the house.

I don't know how much you are paying for the West System resin since I have only purchased it once a long time ago, but look at US Composited 635 thin resin. They offer 3 hardeners with varying pot lives. The nice thing is there is no Hazmat to ship the hardeners like some resin systems have. This is my usual go to resin for general carbon graphite work. It will definitely benefit from a post cure. I am happy with it, the Tg is around 195F, and it cures quite hard. I have made several molds with it, and I too use cabosil and graphite to harden the surface coat.

Scott


EDIT
OOPS, I just reread the original post and noticed the OP is in the United Kingdom. That may make obtaining USC resin a problem for him. Sorry.
The information still applies, just not to solve his problem. I would go back to my original recommendation of MGS resin.

I checked on my cowl repairs last night, so after a 24 hour cure it is rock hard. Quite pleased since these cans have sat on my shelf for at least a year or more since the last time I used them, with the pumps still in them. If anything, the shelf life seems pretty good with WS, and ease of use is right there too. One thing I do after slopping it on and satisfied with the outcome is hit it with my heat gun, the one used for stripping paint, and get it nice and hot, brush back any runs and drips and then once cooled, let it set. I do this for making molds and repairs, but not when making parts, I want that flexibility for removing the parts from the mold, then letting it harden slowly. I found that doing this also helps when putting the cowl on the plane, if its too stiff it can crack or craze.

It all depends on its use.