Quote Originally Posted by Desertboy View Post
This will set me back another week but after extensive talk to someone in the know I've decided to pour epoxy resin inside my aluminium extrusion (Gantry only for now).

Probably this stuff
http://www.mbfg.co.uk/epoxy-resins/p...ble-resin.html

Mixed at this sort of ratio
50% aluminium filler powder
35% Epoxy
15% Carbon fibre powder

Fill these cavities
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I've found out that epoxy resin generates heat in curing which would cause problems but I will bolt the gantry mount on one end fill the extrusion up leaving another space to bolt the top plate on tight. Then I will put the whole thing in a water bath for overnight to cure evenly.

From discussions with the fibreglass guy it'll be stronger than aluminium but weaker than steel for ~4kg's of weight added to the gantry should make it much more rigid.

Will make the gantry mounts with 25mm ecocast to reflect this, I'm going to have a rectangle milled the size of the extrusion so it's embedded 5mm into the mounting plate when bolted in.

Also getting the aluminium drilled next week so it will bolt together with 10mm A2's and will add in the centre struts.
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Not sure if you've done this yet, but it won't make you're extrusion more rigid, or stronger, unless you try to crush it.