Results 1 to 9 of 9

Thread: casting a Banksia Pod

  1. #1
    Join Date
    Dec 2006
    Location
    Oliver Springs, TN
    Posts
    1,726

    casting a Banksia Pod

    I had some time today and cleaned off the counter and generally straightened up the shop for the most part. I found a Banksia pod and decided to try and cast it in some Smooth-Cast 326. Smooth-Cast is a urethane resin similar to Alumilite I think. I don't claim to be an expert, but here's how I go about casting.

    It says in the directions on the SC that is has an open time of 7 min. once mixed. That's plenty of time, but you can't waist time looking for something so you have to have all your stuff ready.

    Here's what I generally use when I cast.Click image for larger version. 

Name:	materials.jpg 
Views:	19 
Size:	58.9 KB 
ID:	89283 The SC has a part A and B and is mixed at 1:1 by volume.Here it is getting ready to be mixedClick image for larger version. 

Name:	scale.jpg 
Views:	18 
Size:	38.4 KB 
ID:	89281 I added some blue dye, turquoise and pearlescent powders to the mix. Click image for larger version. 

Name:	mix.jpg 
Views:	18 
Size:	61.9 KB 
ID:	89282

    I place the banksia in a form. Click image for larger version. 

Name:	in box.jpg 
Views:	26 
Size:	64.3 KB 
ID:	89284 I cut the pod so that it would fit tight and wouldn't float. I was able to get two pieces that fit nicely. I marked on the form where the middle of each piece is and where the seam between them is located so when I cut them apart I can get the best blanks. I didn't get a shot of the poured form, because I mixed too much resin and didn't want to waste it so I used the excess on a single blank form that I have. I put a cutoff of the banksia in this single form and used it for the excess resin.

    I placed both forms on a tray Click image for larger version. 

Name:	rack.jpg 
Views:	23 
Size:	46.9 KB 
ID:	89285 and put it into a paint pressure pot that I use as a pressure chamber.Click image for larger version. 

Name:	in pot.jpg 
Views:	24 
Size:	37.6 KB 
ID:	89286 I ran the pressure up to around 60 psi. Click image for larger version. 

Name:	pot.jpg 
Views:	22 
Size:	47.8 KB 
ID:	89287 Why 60 psi you might ask? The pot has a pressure relief valve that is supposed to be set at 80 psi. Well it's not or my gauge is off! I popped it at around 70 psi once and it scared the holy crap out of me! So, I stop at 60 to 65.

    I'll let the resin sit in the pot under pressure overnight. I've taken them out in an hour before, but I'm not in a hurry so I'll let it sit.

    That's probably as clear as mud!

    John

  2. #2
    Join Date
    Dec 2006
    Location
    Independence, Kentucky
    Posts
    1,355
    Can't wait to see the results.
    I'm supposed to respect my elders, but its getting harder and harder for me to find one now.

  3. #3
    Join Date
    Dec 2007
    Location
    Billings Missouri near Springfield Mo
    Posts
    4,552
    A Turn N Time
    Components for John Smith Organs and the Hobby Organ Builder

    Frog Pond Guitars


    Before you criticize someone, you should walk a mile in their shoes. That way, when you criticize them, you're a mile away and you have their shoes.

  4. #4
    Join Date
    Jul 2011
    Location
    The Gorge Area, Oregon
    Posts
    4,701


    Probably a dumb question (but that hasn't stopped me before..)..

    With something that porous is there a problem with running out of resin once you put it under vacuum? That is I'm assuming that a lot more resin goes into the piece once the vacuum takes hold so how much extra do you need to put in to make sure the pod is still fully enclosed.

  5. #5
    Join Date
    Dec 2006
    Location
    Oliver Springs, TN
    Posts
    1,726
    Click image for larger version. 

Name:	pods cut 2.jpg 
Views:	34 
Size:	128.6 KB 
ID:	89288

    Here they are finished. I couldn't wait till tomorrow. If I do it again, I'll go lighter on the dye, it's a little dark.

    Ryan, I was worried about using enough resin, so I put what I thought was more than enough, actually I could have gotten by with about 10 oz. I use pressure not vacuum. I get good penetration with the pressure forcing the resin into the voids. It's my understanding that the bubbles that are in the resin don't come out like in a vacuum, but are crushed such that you can't see them.

  6. #6
    Join Date
    Aug 2007
    Location
    Reno NV
    Posts
    13,363
    I dont know, I kind of like that dark color. Looks sweet!
    Programmer - An organism that turns coffee into software.
    If all your friends are exactly like you, What an un-interesting life it must be.
    "A door is what a dog is perpetually on the wrong side of" Ogden Nash


  7. #7
    Join Date
    Jul 2011
    Location
    The Gorge Area, Oregon
    Posts
    4,701
    Neat color contrast though!

    Thanks for the details, this is an area I know less than zero about but some of the results are pretty cool! These are looking like they could well be on that list for sure.

  8. #8
    Join Date
    Nov 2006
    Location
    Brooklin ON -- 45 mins. NE of Toronto, ON
    Posts
    868
    Can't wait to see them turned and finished!
    Mack C. in Brooklin ON
    It feels great to sell a pen,
    It feels even greater to give one to a friend!

    If your presence doesn't make an impact;
    Your absence won't make a difference!


    I am a proud supporter of
    "Pens for Canadian Peacekeepers"!

  9. #9
    Join Date
    Dec 2006
    Location
    Independence, Kentucky
    Posts
    1,355
    Nice, those will look nice once turned. What Brent said, the color is not too dark at all
    I'm supposed to respect my elders, but its getting harder and harder for me to find one now.

Similar Threads

  1. banksia pod pen blanks
    By John Daugherty in forum Classified Ads
    Replies: 5
    Last Post: 02-20-2015, 11:34 PM
  2. A small Banksia Platter
    By neil mackay in forum General Woodturning Q&A
    Replies: 8
    Last Post: 09-08-2013, 01:56 PM
  3. First Attempt At Casting .............
    By Les Elm in forum Lathe Project Showcase
    Replies: 7
    Last Post: 06-07-2010, 03:55 PM
  4. My First PR Casting
    By Les Elm in forum Lathe Project Showcase
    Replies: 11
    Last Post: 05-18-2010, 03:11 PM
  5. banksia seed pods
    By Dale Johnson in forum Lathe Project Showcase
    Replies: 2
    Last Post: 12-09-2007, 03:35 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •