Vacuum finishing in the Mk IIIA Terpenator tank

For those of ya’ll who would like to vacuum finish your BHO extract in the Mk IIIA tank itself, check out this lid that I made out of $2/lb remnants from Multi Craft Plastics, and a bulkhead fitting with O-ring, and a 1/4″ flare fitting from Paramount Supply.

Since the opening is only 6″,  1/2″ acrylic is heavy enough and works well to allow you to watch the vacuum purge progress.  You can set it a pot of warm water for heat.

Mk III purging lid-1-1

6 responses to this post.

  1. Posted by Adam on July 1, 2015 at 4:06 AM

    So, i can use directly the gathering unit of terpp mkIII to purging the extract?


  2. Posted by RightCoastDabber on September 2, 2013 at 11:45 AM

    Be careful with the acrylic as it will crack. thats the beauty of polycarbonate. If you take a thinner piece of each and attempt to bend them both; the acrylic will crack when you bend it and the polycarbonate will only bend to a full 180 degrees and then return. Granted with a smaller diameter chamber it doesnt matter that much.

    Also try using a rubber industrial vacuum cup to attach to your top. the threads with the forces of full vacuum upon it only weaken the plastic top… and also cause a potential leak considering the connection is to plastic. ESPECIALLY if the hole is in the middle where the top sees the most flex. the hole close to the edge is ideal IMO.

    My 2 pennies… 🙂


  3. Posted by Organical on July 8, 2013 at 1:48 PM

    so you are just using the buna gasket from the terpenator to seal between the terp and the plastic?


  4. Posted by Victor Mueller on June 18, 2013 at 10:08 AM

    I like it. Simple and nice. If a 12″ diameter pot was used how thick would the acrylic have to be?


    • About 1 /14 to 1 1/2″ thick. Our 1″ acrylic panel still bows 1/6″ under full vacuum.

      Some flex is OK, but we are also using heat and eventually high cyclic fatigue is likely to result in stress cracks, leading to eventual failure. Heat significantly lowers the properties of acrylics and polycarbonates, so I design to the heavy end and we are currently using 1 1/2″ Polycarbonate for our 12″ vacuum chamber, but continue to use the 1″ panel for the 10″ Mk I & II Terpenators.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: