Posted: Sun Mar 23, 2014 7:04 am
No probs,
will put some in a freezer again...Results tomorrow.
will put some in a freezer again...Results tomorrow.
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The pouring urethane sidewall thread
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Posted: Sun Mar 23, 2014 9:43 am
Just FYI, I hit samples of the Adiprene with a sledgehammer after leaving it in a freezer at -25 C over night and it didn't take any damage whatsoever.
Posted: Sun Mar 23, 2014 2:22 pm
I think sample size is important here guys.
How thick and how wide are the samples?
How thick and how wide are the samples?
Posted: Sun Mar 23, 2014 7:40 pm
The other parameters are equally important, hammer weight, distance etc.
As said "1/4" wide (my router bit) by 5-6mm high" for a pre cured rails.
This one is not pre made, so poured and cured, no pressure, etc, and is 4mm thick, glued 2 peaces with epoxy.
The hammer weight is 1190g, I hit the sample from about 15cm with the hammer edge:
Then hit it from about 30-40cm with a hammer head:
Repeated the above after the sample was on the Sun for about 20min:
I recon the above does not mean much since not done in a lab...
The sample is also quite thin, not sure if you guys are making the same.
But this is interesting, when I bend it, it does not break! Not frozen sample breaks. Hm...Might try this again.
As said "1/4" wide (my router bit) by 5-6mm high" for a pre cured rails.
This one is not pre made, so poured and cured, no pressure, etc, and is 4mm thick, glued 2 peaces with epoxy.
The hammer weight is 1190g, I hit the sample from about 15cm with the hammer edge:
Then hit it from about 30-40cm with a hammer head:
Repeated the above after the sample was on the Sun for about 20min:
I recon the above does not mean much since not done in a lab...
The sample is also quite thin, not sure if you guys are making the same.
But this is interesting, when I bend it, it does not break! Not frozen sample breaks. Hm...Might try this again.
Posted: Mon Mar 24, 2014 7:51 pm
More tests.
Pre cured PU on 50psi, in a freezer for 12h, sample size 6.12x7.4mm:
Hammer edge from 10-15cm:
Bent sample, clear break (no visible air bubbles:):
Bent sample not frozen - at this angle the frozen part snapped:
Hope this helps...
Pre cured PU on 50psi, in a freezer for 12h, sample size 6.12x7.4mm:
Hammer edge from 10-15cm:
Bent sample, clear break (no visible air bubbles:):
Bent sample not frozen - at this angle the frozen part snapped:
Hope this helps...
Posted: Tue Mar 25, 2014 12:15 am
If I recall correctly I hit the sample (about 12x10x200 mm) with a 2500 g hammer that was dropped onto the sample from about 1 m. The sample showed no signs of damage. It also doesn't snap when frozen no matter how much you bend it...but I guess most of these properties can be accounted to the softness of the material at 95 shore A compared to the 70 shore D of the Smooth-cast 310.
Posted: Tue Mar 25, 2014 4:05 am
True.
For me it's abut the cost as well. One "trail" PU package ~1kg about AU$30.
And quite easy to work with since it's like water. PMC790 is like honey, for me, not easy to pour at all.
For me it's abut the cost as well. One "trail" PU package ~1kg about AU$30.
And quite easy to work with since it's like water. PMC790 is like honey, for me, not easy to pour at all.
Posted: Tue Mar 25, 2014 4:54 am
The Adiprene is like honey as well. I always heat the resin part in the microwave prior to degassing it to make it more liquid which helps with evacuating the air. Then I add the hardener and degas once more before pouring. With low workshop temperatures the resin starts to thicken again before pouring, so I pour honey most of the time as well. Mind you, the resin is supposed to be kept at about 60°C for the whole process, so in an ideal environment it would be more watery.
Problem with the Adiprene resin is that it needs to be sealed from oxygen pretty well, so always make sure to top up the container with some heavy gas (we use a propane/butane blow torch and just hold it into the container). If you don't do this the top layer will solidify and cannot be brought back to a liquid state by heating. In general the Adiprene resin part needs to be stored at quite warm temps (around 30°C) in order to stay liquid.
Problem with the Adiprene resin is that it needs to be sealed from oxygen pretty well, so always make sure to top up the container with some heavy gas (we use a propane/butane blow torch and just hold it into the container). If you don't do this the top layer will solidify and cannot be brought back to a liquid state by heating. In general the Adiprene resin part needs to be stored at quite warm temps (around 30°C) in order to stay liquid.
Posted: Thu Mar 27, 2014 5:31 am
I'll have some Smooth On PMC 790 samples soon as well. Pre casted on 60psi.
If someone is interested...
If someone is interested...
Posted: Wed Apr 02, 2014 10:19 am
How did the test turn out?dbabicwa wrote:I'll have some Smooth On PMC 790 samples soon as well. Pre casted on 60psi.
If someone is interested...
Posted: Fri Apr 04, 2014 2:42 am
The PU PMC 790 test, same size, cured on 50psi, same dimensions.
Hammer test, no visible break:
The finger nail imprint:
Bend test from a freezer after 2 hrs:
No visible air bubbles, some marks duno what that is, almost transparent:
Hope this helps to someone.
Hammer test, no visible break:
The finger nail imprint:
Bend test from a freezer after 2 hrs:
No visible air bubbles, some marks duno what that is, almost transparent:
Hope this helps to someone.
Posted: Fri Apr 04, 2014 10:43 am
Stuff looks pretty tough, big thanks!dbabicwa wrote: Hope this helps to someone.
Posted: Fri Apr 04, 2014 12:59 pm
Yet soft.
Posted: Fri Apr 04, 2014 2:14 pm
90 shore A should be harder than that.
Posted: Sat Apr 05, 2014 6:49 pm
Hi everybody, I'm a new member. Love the site.
Just wanted to ask dbabicwa, where do you buy your smooth on products?
I'm also in Perth WA and just paid $55 off ebay.
I'll be testing my pressure chamber soon and will post some results. I made mine a little different in that it is just made of timber but the side height is only 20mm to minimize the load along the edge and I then have it in my press with my layflat hoses and cat track all assembled on top. It all builds pressure at the same rate so the chamber is equal pressure inside and out. The sides are the only part that can possibly fail but these are 40mm thick and well bolted.
Hopefully testing it next week so we'll see how I go
Just wanted to ask dbabicwa, where do you buy your smooth on products?
I'm also in Perth WA and just paid $55 off ebay.
I'll be testing my pressure chamber soon and will post some results. I made mine a little different in that it is just made of timber but the side height is only 20mm to minimize the load along the edge and I then have it in my press with my layflat hoses and cat track all assembled on top. It all builds pressure at the same rate so the chamber is equal pressure inside and out. The sides are the only part that can possibly fail but these are 40mm thick and well bolted.
Hopefully testing it next week so we'll see how I go