DIY solid pultruded type rod.

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#1

Hi folks,
I am constructing a three wheel buggy that requires 25mm diameter rear fibreglass suspension axles. Cant buy any here in the Philippines so I will try to make them myself. The method I will use will be to add release agent to the inside of a length of 25mm.ID ( 1" to those countries still catching up :smiley: ) rigid PVC electrical conduit then pack it loosely or tightly? with glass roving then using a vacuum pump, suck the resin up through the PVC then wait for it to cure.
Iā€™m confident this will work but Iā€™m not sure about the glass/ resin ratio, will more glass make the rod stronger and less brittle?
The glass roving will be from dismantled heavyweight woven roving as I couldnā€™t find a roll of the rope type.

Thanks, Bob.

#2

More glass will make the rod stronger yes, but Iā€™m not confident your method will work at allā€¦ What resin are you using? How are you going to ensure vacuum integrity through the tube? How are you going to control resin flow through the tube?

#3

A clear plastic tube will be used to vacuum the mixed laminating resin into the bottom of the airtight upright PVC tube from a container. Once the resin is drawn through the glass roving to the top, the plastic tubing will be pinched off to prevent it from returning to the container.

#4

It would be much easier to do it with aluminium tube.

Wet your glass fibre out 50/50 ratio , fold it over length wise , loop heavy fishing line through the fold and pull it through the tube.
Depending on length it could get hard , but you donā€™t want it to be easy as you want maximum fibres in there.:slight_smile:
You can do it with a slide hammer or winch of some sort , even a block and tackle chain winchā€¦ Or a descent fishing reel might do it.
Once cured just drop it into some caustic sodaā€¦ After about 4 hours you aluminium is gone and you will have a nice rod.

Beats trying to suck resin through and playing around with vacuum :cool:

Tim

#5

You could always take some loose tows, soak in resin, and then pull tight, allowing it to cure. Either sand smooth, or add outside layers to even out the surface. Oversize it if you sand, else you will be sanding your strength away! :slight_smile: If you donā€™t care about outside smoothness, then just soak, tighen the ā€œropeā€ and then let cure! maybe when tight, you can wrap mylar or something around it, to tighten the bundleā€¦a slight twist might tighten the bundle as well, but then you have a rod that might have weird properties.