I would have printed the whole barrel, but CURA 2.5 added a 5mm thick layer across the whole barrel at 70% ... not sure why, but I'll try again with Cura 2.6.2 next.
Yes, even this design can be a FREE download once I am fully funded for my RoboGuts™ S.T.E.A.M. Education Program Kits;
IF each viewer donates just $5 I'll be funded almost overnight and then all my designs become FREE downloads!
The fastest and cheapest way to get all my .STL files FREE is to donate $5 to help fund school materials ... once I have $3,500 I'll convert all these files to FREE downloads. https://www.gofundme.com/roboguts-kits-lessons