I've experimented with most of the material available.Even tried glass filled Peek and Pet P but found it abrasive to the seat.I cut the valve seat concave and then polish with a hard felt bullet.A little oil and light abrasive takes out any imperfections in short order.
When making a poppet if it's thread on or pressed on I don't turn it to the final diameter or cut the face. I leave it a little oversize for a couple hours because the poppet material changes shape from the pressure of the stem.
Also the cheaper gear drive lathes tend to induce chatter into the plastic surface from just gear rattle . No matter how sharp and slick the cutter is . It’s a pain in the butt sometimes
Quote from: Brian W Cook on February 03, 2023, 10:46:01 AMAlso the cheaper gear drive lathes tend to induce chatter into the plastic surface from just gear rattle . No matter how sharp and slick the cutter is . It’s a pain in the butt sometimesMy old 9X19 is belt drive, I removed all the gears and power feeds from it and replaced the bearings, trued up the 3 jaw chuck. The cross slide could be tighter but there is no chatter on aluminum or brass so the peek suprised me.
Quote from: Firewalker on February 03, 2023, 05:11:04 PMQuote from: Brian W Cook on February 03, 2023, 10:46:01 AMAlso the cheaper gear drive lathes tend to induce chatter into the plastic surface from just gear rattle . No matter how sharp and slick the cutter is . It’s a pain in the butt sometimesMy old 9X19 is belt drive, I removed all the gears and power feeds from it and replaced the bearings, trued up the 3 jaw chuck. The cross slide could be tighter but there is no chatter on aluminum or brass so the peek surprised me.Tooling rejecting to cut ... not sharp enough IMO
Quote from: Brian W Cook on February 03, 2023, 10:46:01 AMAlso the cheaper gear drive lathes tend to induce chatter into the plastic surface from just gear rattle . No matter how sharp and slick the cutter is . It’s a pain in the butt sometimesMy old 9X19 is belt drive, I removed all the gears and power feeds from it and replaced the bearings, trued up the 3 jaw chuck. The cross slide could be tighter but there is no chatter on aluminum or brass so the peek surprised me.