So, after producing 15 or so poles on my x winder I was wondering what everyone has been using for their mandrels? So far it looks like cardboard is popular, but I imagine this would be too inconsistent for my parts. I have read that mandrels should have a slight taper, to help with removal, so was thinking about 3d printing some mandrels and then giving them a wrap on the filament winder (to add sufficient strength) and I would then use these as the future removable mandrels for my projects. Has anyone found better sources of mandrels?
I am very keen to develop some better mandrels as the tube stock I have been purchasing has been very difficult to remove from the finished part unless I use many layers of cash register tape (which causes it’s own problems). Has anyone developed a good way of releasing their finished parts?
Replies
Wood, Fiberglass, plastics all work. If cost is not an object use teflon. Obviously the part will not adhere and the CTE of Teflon is your friend. Wind the part and let it cure someplace warm, hot is even better. (A garage in Oklahoma summer for instance)
Once the part is cured, drom the mandrel and part into the freezer. The teflon shrinks more than the carbon part. 2 hours later come get it out of the freezer and whack a mallet on one end ot the mandrel. be ready to catch it as it shoots out the far end.
Almost any material (not wood) will have a CTE you can use. Just choose your mandrel material so it has a HIGHER CTE than your workpiece.
Hi,
sometimes I use a chrome steel tube, high polished and separeted.
Milos
Hi
This isn't really on this topic. I was hoping to find out how you all start a thread. I have a 4 axis winder that I'm having issues with.
I don't see a place to start a new thread. Any help would be appreciated.
greg
If you are using a very rigid mandrel, like aluminum or wood, you can make a press collett the same diameter as your mandrel and push it through. Depending on the length of your part, you may need to use pipe vises..Then work it through with a smaller diameter rod..I learned this from making fiberglass boat parts as a shipwright apprentice, it works well and no need for a taper.
I have success with collapsable mandrels.
I'm about to test a taper for the first time,
5 gallon bucket taper! Plus 4 coats of paste wax. The perfect lamp shade!
Perhaps I had too much time on my hands that week. :-)