Thread: First cast

They all look good.
Much better than any of my first castings.

I can show you some (they all came out brown).

If your going to be drilling them down the centre try putting a nail thru duct tape over the top of the conduit to stop things floating.
Are you painting the tube or the inside of the blank or both?

Peter

its quite a learning curve so much can go wrong

to keep blocks in the bottom of a tube i usually use a icey pole stick as a wedge or even cut one to length so it sits just above the top of the mold and a bit of gaffa/electrical tape to hold it down

i have used conduit a bit in the past and i seal the bottom edge with gaffa tape - easy to apply, seals well and you can push through it to knock the blank out

i can't help with the pods, i haven't done them

keep it up, you have some pretty good results already

all the best

MIK

Dallas,
Nice work, as mentioned above they all look great !! fantastic first attempts. Hard to pick a favourite

Cheers
Tony

Thanks for the ideas on the floating wood. I have got some skewers here that I could cut down to length. Stupid me, I was thinking that using something to hold the wood down would show up in the cast, but as Fly says, if it is in the centre it will be drilled away when making a pen.
I cut off the tips of fingers from a glove and slid them over the end of the conduit to seal it.
I did paint both the tube and the inside of the blank. This time I used nail polish and found it hard to see the coverage inside. I think I will go back to using a spray can as I have never had glue show through before. Just didn't have a can for this job. Next time I will use white or something similar for the translucent colours.
Thanks for your encouragement guys.

Great results ther!! I particularly like the casuarina pods - looks a bit like a snake skin!!!

Very impressive, well done, Amos

Originally Posted by Treecycle

The first one is some decayed Redgum Burl with Sky Blue Perlex. The cast went okay, but the burl was too short and I ended up with a big blob of resin on one end as the burl floated. What is the best way to stop this happening?

Push them down some how. I have used sticks, weights (timber blocks in plastic), even caps that have short dowels (for banksia, each vertical tube has its own dowel) covered in silicon.

Originally Posted by Treecycle

The second was another piece of Burl (Coolabah) cast in some purple resin. Mistake made here was I painted the tube and blank black, and now the resin looks black instead of purple. I obviously did not get the inside of the blank fully coated as some of the glue can be seen through the resin.

Painting the tube will not stop showing the glue, only the blank, but as you did both something was missed. What sort of purple, dye, solid or Pearlex? Dye is translucent and will show black, Pearlex will often show through as when thin it is translucent (especially if not enough Pearlex), pigment should be fine but only if enough pigment is used.

Originally Posted by Treecycle

Third was some Sheoak seed pods cast in the purple again. Same problem with painting black inside, but also had problems with the purple not getting into all the cavities of the seeds. I had to fill the missing cavities with coffee grinds and CA. Came up okay in the end, but very dark. Not sure if the lack of resin penetration was due to it starting to go off before I got them in the pressure pot.

Same issue with type of colouring as above. As for holes, if using a horizontal bed mold you must mix the resin and pods together first before placing in mold, if vertical mold should be OK. If you are pouring in resin over the top and it has already starting to go off, yep too late

Originally Posted by Treecycle

The last one is what I would consider the best of a bad bunch. Again it is Redgum Burl cast in Sky Blue Perlex.

Try try try again and sooner or later it will work. Looks fine to me

Neil, it was a translucent die I used. Is there a preference between translucent and solid dies?
What is the recommended time that casts should be left in the pressure pot?
I did another little batch yesterday afternoon so we will see how they go.

Originally Posted by Treecycle

Neil, it was a translucent die I used. Is there a preference between translucent and solid dies?

Depends on what you want, translucent is see through, so black tubes will shine through . There are no solid dyes, they are solid pigments, which provide a solid non-see through colour.

Originally Posted by Treecycle

What is the recommended time that casts should be left in the pressure pot?

I recommend overnight, to 24 hrs on cooler days. It depends on the temperature, but PR must be left under pressure until the cast has completely set hard, otherwise it will shrink away from the wood. Under pressure the cast is effectively at a lower temperature in the pot that you must remember. Many casters make the mistake that because the resin left in the cup has set (outside the pot), that the cast inside the pot is set also, big mistake as it won't be.

Sweet work there mate now u are the slippery slope ;-)

Ian