Well i was hoping to give you my full test results today, sadly whilst gathering up all the pre-cut samples i dropped some of them. For the most part they survived hitting the tiled kitchen floor mostly flat side on too for that matter but sadly two of the pre-cut control samples (pure plaster no pulp) shattered & need to be re-cast. I was able to continue on with the remaining samples, but i won't give you the full results until i replace these control samples. Unfortunately this means at least another two day wait as i want to give them at least two days since they are being cast in plastic tub lids. I won't be demolding them until they have gone off (hardened) sufficiently overnight. Then allowed them to fully air dry for another full twenty four hours.
I can however show you some pictures of just how i went about doing the weight/strength testing. Just in case some people did not grasp what i meant in part 1 of this set of experiments.
THE 'PRE-CUT' SAMPLES:
These are the pre-cut samples i created from the various plaster pulp mixes for my experiments. As you can see they are of identical size & shape having been moulded from identical large plastic ice cream tub lids. As i want the best of the resulting mixes (the best of the best) for both free hand sculpting & use in moulds too later i didn't work the mixes into the plastic lids too much. As you can see if you click on the above image to enlarge it. The casts are somewhat 'pock marked' with holes. At this point i just wanted them to be the same size & thickness so the final cut down samples would be as close as the same size as i could get them.
CUT DOWN TEST SAMPLES FINAL SIZE/SHAPE:
Here you can see i have cut the larger demolded 'original’ samples down into two matching pieces each ready for the strength testing. These each measure 16cm x 10cm x 7mm. These final sizes as well as weights, contents & weight tolerances will be given in the final results chart later. Now to how i tested their strength.
A SIMPLE PENDULUM WEIGHT TESTING TOWER:
Not having any 'free weights' laying around i needed to find a method of recreating an identical weight test for each sample. The solution was quite simple in the end (always look for the easiest answers first) having a ample mixed supply of card stock which includes tubes from rolls of foil but also the very boxes the rolls of foil come in too. As you can see two boxes hot glued to a scrap of ply wood make for a strong 'fixed' pair of towers to form a simple but effect pair of pillars for a pendulum weight tester.
HOW THE TEST WAS PERFORMED:
Here you can see the setup for the actual testing, or how i will be carrying it out at least. Each sample is placed as close to as identical a position on the top of the towers as i can get them. A large (3ltr) plastic bottle was then hung from each sample connected by use of a small strong piece of wire (close up on the wire below) which like the samples was placed in as close to as possible the same position each time in the centre of each test sample(s).
I then slowly filled the plastic bottle with water until the sample(s) simply 'snapped' under the weight. Constructing the tower at just the right height & using a wide bottomed plastic bottle meant when each sample broke the bottle only had a short distance to fall. This meant it did not fall over easily preserving the water inside. I then simply had to weigh the bottle & contents for each sample.
A CLOSE UP ON THE WIRE ATTACHMENT:
Now it stands to reason simply running a length of wire over the centre point of the samples would simply not give me a reasonable or fair test result. Not all the points of any sculpture are as fine or as limited as the thickness of a thin piece of wire. I may as well have ran a hot knife through butter than used those test results if i had gone with that option. So i decided to give the samples a fair (i felt anyway) compromise by adding a small craft stick under the wire. As you can clearly see the craft stick is only slightly wider than the sample(s) & i have 'not' run it along the length of the sample(s). Had i run the craft stick along the length of the sample(s) that would have added a support strength of a type & magnitude i would 'not' be using in future projects with this type of pulps anyway.
The final test results for the most part were as i expected them to go. However two of the pulp mixes did better, far better than i have ever have dreamt. Indeed they surpassed my expectations so much that the secondary batch of mixes i had in mind to make & test are simply no longer required. I have two mixes from this first wave of tests i am certain that with some minor adjustments will not only give me what i was looking for but again surpass my wildest dreams many times over.
I am not going to say which of the test mixes they were just yet or what adjustments i have in mind. I will say however, of the first test mixes i gave you all in part one of this feature two of the test mixes had a weight/strength tolerance of 'over seven lbs limit (or over three kg). That may not sound like much on the surface but remember these samples are only seven millimetres thick & the actual unsupported weight bearing area of each sample was only some nine centimetres wide!. You may not think it but that IS quite impressive. Once i make the adjustments i have planned for the two chosen mixes i am certain i can at least double this. Of course i (we) have to remember here this whilst not new territory by a long shot in the search for such pulp(s), Whilst no one has come forward (to my knowledge) claiming to have found the perfect plaster pulp mix, i have at least made two potential break through so far. If they will ultimately take me where (i hope) expect them too is of course another matter. Then again that’s the life of an experiment for you eh lol.
The full results very soon.
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