Just wondered if anyone could explain the difference between the above?  The high temp system seems simpler and cheaper.

They are completely different resin chemistry.  The Uni-mould system is based on vinylester and polyester and is suitable up to 90C.   The EL160/EG160 high temperature epoxy system is epoxy based using a high temperature epoxy that is suitable for use up to 160C which is much higher. 


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

EL160 renders Uni-mold redundant? Can't see the point in paying more for a less versatile system. Unless there is a benefit of Uni-Mold I am missing.

You must have got something wrong here. I guess you are talking about the moulding paste. You will need at least the high temp gelcoat in addition. This will be least 110£ for the smallest batch, wich is 5+1kg. For less than 80£ you can get the small unimould starter kit, wich is 1+1+5kg + csm. and the paste has to be used much thicker than a csm mould. You'll get much more mould for the same money with the unimould system. And the high temp paste is only more versatile if you use high temps. Basically only when using prepregs.

Epoxy is also harder to work with. Systems like the Unimould are extremely forgiving and easy to use, epoxy systems are significantly less forgiving and often hard to repair if you do make a mistake.

Yes, you are right, Uni-Mould is cheaper, apologies.  I made a mistake with my numbers.  Still, a female for my telescope tube project is running to £600 (plug and female).  And that is before I even consider composites, vacuum bagging and infusion.  Any advice to bring the cost down?

What for an telescope are you building? Something mounted in a medium sized building? With the big starter kit you could definitely build quite a huge telescope mould. Usual mirror telescopes should be even possible with the small kit. and that's 260/80£. Unless you are cnc'ing the plug out of epoxy board, that should be far less than 600£ in total

The tube is 1.5m x 0.3m, unfortunately just a bit too big for a small kit per side.  I have worked out that to finish the plug (sonotube), the parts come to £227.64, this includes a laminate skin, pattern coat, polish etc.  Add the £314.40 for the large kit and that is £542.04.  I could save a bit of money by using 3 small kits, but for all I would save I might as well get the large.

The area per side is 0.8 sqm.  Do you think I could stretch the 0.7 sqm in the small size kit to this size?  It may be worth considering.

Is it a simple tube? If so, I would get a 300mm brown kg type tube (kanal grundrohr in german) and take a would from it, using a melamine coated board as temporary flanges. And then just sand the closed mould beginning with 400 grit and polish each half separately.
That's far less than 100£. You could get away with little over 50£. You could try to buy 1 small kit and 1small of each gelcoat, coupling coat, tooling resin and help and csm. you don't need a second roller. if you need more than half the resin for the first half, you could reorder before starting the second. But I would say you should buy 2 of each from the beginning.