Ray, how specifically are you attempting to remove the mandrel? What type
of propellant?
As Steve mentioned, timing is important. With KNDX (and KNSU) I remove the
mandrel after 45 minutes (while still lukewarm). With KNSB I wait 48 hours.
Mandrel should be steel, not aluminum, and reasonably polished (no rust on
it). For release agent, I use silicone grease, a very light coating. To
remove, I clamp one end of mandrel in a bench vise, then give a sharp twist
to the grain (or mould), it should snap free. Sometimes with larger
mandrels, you may need to use a rubber strap wrench:
https://www.harborfreight.com/2-pc-rubber-strap-wrench-set-69373.html
On Thu, Oct 4, 2018 at 9:56 PM Ray Rocket <dmarc-noreply@xxxxxxxxxxxxx>
wrote:
Not sure why, but the last few attempts at casting have resulted in stuck
mandrels. I've never had this problem before. I'm using electropolished
stainless steel tubing for a mandrel, sprayed with Pam cooking spray. This
has worked just fine in the past.
What are you guys using for mandrels and release agents?
