And because I could not buy the ceramic bearing blocks I wanted, I just made some up. Something spearfishing related to do when the weather was horrible.

That cuttle barrel looks very cool any pics from the top to take a look at the shape?

Do you think when loading, the rubbers rub on the body making it harder to load?

Popped another out of the mould from previous post but made it a conventional setup. bit of a different finish gold foil in epoxy, may have gone slightly over board with the foil.

i have the full thread on http://forums.deeperblue.com/threads/carbon-fiber-speargun-build-step-by-step.122757/ 

will post some highlights here, 

start with a computer model.

3d print some moulds 

mould some carbon skins 

add some reinforcements

make a handle 

smack it all together and boom inverted carbon roller with rear rollers 

The ermes double roller mech are so so very nice. the ceramic pulleys are for inverted roller?

You can see the mould off to the right of the pictures its the white thing.

Method i used was wet lay vacuum bagging in a mould. Because i use a mould i dont have an internal core only stiffeners at certain position to help transfer load from top skin to bottom skin. When i lay the carbon i always make sure to know what the gun will be as an inverted roller will need more reinforcement on the top of the gun while a conventional gun will need more on the bottom, a roller can be even top and bottom. The muzzle roller diameter is different for most of my guns as when i drill the holes it can be up or down a couple mm. I make them big enough so the rubbers dont rub on the body but small enough that the rubber line up nicely with the shaft.  

Ill do a write up of the inverted next but would like to go test it first. anyone got a pool in auckland willing to let me shoot some foam .