The pouring urethane sidewall thread
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evening AU chaps. Is this the stuff on ebay? http://www.ebay.com.au/itm/Polyurethane ... 0799166100
I like in the video when it turns white. Pretty cool. Are you colouring it?
DC
I like in the video when it turns white. Pretty cool. Are you colouring it?
DC
Are you making skis or boards or something else?gav wa wrote:thats the stuff. The other guys here have heaps more experience with it than me but 1 thing I will say is make sure you have wide mixing pots. Last time I mixed it in a 1 litre mixing pot and pot life was shortened by about 50%
The white PU (325 I think) does not work with pigments, 327 does.
dbabicwa - I'm making boards mate.
I only got a pot life of about 4 minutes before it started to thicken very quickly. My pot was about 4-5 inches across at the bottom and I mix by the weight recommended on the included instructions, measured on a very accurate set of digital scales.
I've checked out your blogs and those kite boards are very impressive.
One thing I was going to ask you though, considering you are premolding your edges, have you tried simply letting it cure at atmospheric pressure?
Without the moisture coming through from a wood core you shouldn't get any foaming. In the test batches I've done in plastic containers not a single sample has had any bubbles at all.
This is the reason I am going to try lightly sealing a channel with the same epoxy I'm using in the lay-up and seeing if after this dries smooth cast 305 doesn't bubble when hardened at atmospheric pressure.
Might not work but worth a try.
I only got a pot life of about 4 minutes before it started to thicken very quickly. My pot was about 4-5 inches across at the bottom and I mix by the weight recommended on the included instructions, measured on a very accurate set of digital scales.
I've checked out your blogs and those kite boards are very impressive.
One thing I was going to ask you though, considering you are premolding your edges, have you tried simply letting it cure at atmospheric pressure?
Without the moisture coming through from a wood core you shouldn't get any foaming. In the test batches I've done in plastic containers not a single sample has had any bubbles at all.
This is the reason I am going to try lightly sealing a channel with the same epoxy I'm using in the lay-up and seeing if after this dries smooth cast 305 doesn't bubble when hardened at atmospheric pressure.
Might not work but worth a try.
Thx Gav
305 I did not try, but like with any I think it expands first and than it shrinks. Quite a bit with both. That is the problem and a nightmare to clean after. At least for me.
With premoled if I could get the exact thickness every time (which I don't yet), placing and finishing edges would be really fast. Like a minute or two.
The idea is to have almost perfect size, ready to go when glassing. More and more I think the only way to achieve this is to machine the edges to the needed size. But how to, I do not know?!
D.
PS
And premolded mate, coz I use all PU in about 1 day after opening. Once you open it it will go off really fast...Even with Argon or Nitrogen on top.
Thx for the alu info as well.
305 I did not try, but like with any I think it expands first and than it shrinks. Quite a bit with both. That is the problem and a nightmare to clean after. At least for me.
With premoled if I could get the exact thickness every time (which I don't yet), placing and finishing edges would be really fast. Like a minute or two.
The idea is to have almost perfect size, ready to go when glassing. More and more I think the only way to achieve this is to machine the edges to the needed size. But how to, I do not know?!
D.
PS
And premolded mate, coz I use all PU in about 1 day after opening. Once you open it it will go off really fast...Even with Argon or Nitrogen on top.
Thx for the alu info as well.
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How did you go?gav wa wrote:dbabicwa - I'm making boards mate.
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This is the reason I am going to try lightly sealing a channel with the same epoxy I'm using in the lay-up and seeing if after this dries smooth cast 305 doesn't bubble when hardened at atmospheric pressure.
Might not work but worth a try.