Mixer Posted December 18, 2018 Posted December 18, 2018 (edited) By that score, 2g /10g *100 is 20%. If your sample started at 1.126g and weighed 0.734g after drying, you`d have 0.734 / 1.126 *100 which is 65% solids Yup, I inserted the wrong figure......solids result still the same tho Amended results for both. Wickes paste. Original weight of paste = 1.126 Weight after evaporation = 0.392 Decrease in weight = 65.19% Solids content = 34.81% Polycell paste. Original weight of paste = 1.126 Weight after evaporation = .437 Decrease in weight = 61.19% Solids content = 38.8% Edited December 18, 2018 by Mixer
Col Posted December 18, 2018 Posted December 18, 2018 (edited) I used the numbers you posted The decrease in weight by these numbers is not 65% or the weight after evaporation would be 0.392 (ish) not 0.734 Here you go......... Original weight of paste = 1.126Weight after evaporation = 0.734Decrease in weight = 65.19%Solids content = 34.81% I would imagine any paste with 80% water would pour like milk The sample is getting pretty close to fully dry so it looks like the solids will be in the region of 18-19% Edited December 18, 2018 by Col
Mixer Posted December 18, 2018 Posted December 18, 2018 Its supposedly the same paste in the same tub so i doubt they would have doubled the amount of water in it, its not what you could call a thin paste Dag`s Roman 880 estimated 32% solids, might be worth a test to see how close it is. Cant find any spec for the wickes so there`s nothing to go on.http://romandecoratingproducts.com/files/6515/1620/1781/PRO-880_TDS_011618.pdf.What could be the answer then as you have around 20% showing?
Col Posted December 18, 2018 Posted December 18, 2018 I can only post the results i`m seeing, did you leave the lid off yours during the heatwave?
Mixer Posted December 18, 2018 Posted December 18, 2018 I can only post the results i`m seeing, did you leave the lid off yours during the heatwave? Nosiree, kept in a cool cupboard, and it pours ok
Mixer Posted December 18, 2018 Posted December 18, 2018 Roman 880Dilution: May be diluted with up to one pint of clean water per gallon. DO NOT OVER DILUTE. I think dag was trying 1-1 If i hung wallpaper at that dilution it would be on the floor a few minutes later
dagabu Posted December 18, 2018 Posted December 18, 2018 (edited) That is correct, the paste was still viscous and unable to be spread onto the paper without severe distortion so I kept cutting it until it was thin enough to roll out. I have perhaps 20 tubes rolled and dried on my "high tech" tube drying system, all weights are in the 'dry' range and tested using the accepted method (NEPT in-house) of burst strength and survived 6500 LPI with very little distortion. PVA cut 1:1 had even better results. Edited December 18, 2018 by dagabu
Col Posted December 18, 2018 Posted December 18, 2018 That makes sense, the diluted Roman would be around 24%, diluted pva around 37%. The two glues should be compatable in solution so you could try using a mixture of both.
Col Posted December 18, 2018 Posted December 18, 2018 Starch paste and pva can be mixed together without any drama or slimey outcome
Mixer Posted December 18, 2018 Posted December 18, 2018 I can only post the results i`m seeing, did you leave the lid off yours during the heatwave? It might be a good idea to scrape out the paste residue when dry and weigh it to see if it corresponds to the math
Col Posted December 18, 2018 Posted December 18, 2018 well its now bone dry and the result is 18.8%, it`ll come in handy for something but it wont be rocket tubes
Mixer Posted December 18, 2018 Posted December 18, 2018 (edited) I think I have it figured Col. It seems you must have tared the scale when putting the paste in the cap, but when you made your calculations you took the 1.4g off giving a false number as it was already off. You actually only had 10g on the scale. So now if it reads 3.3g........3.3/10 x 100 = 33 That 33% would be your solids. Edited December 18, 2018 by Mixer
Col Posted December 19, 2018 Posted December 19, 2018 nope thats not it Here`s the dry glue from the cap which confirms the result.
Mixer Posted December 19, 2018 Posted December 19, 2018 (edited) Well, ALL PREVIOUS SOLIDS TESTS NULL AND VOID. I have just weighed the solids from a 10g test of the Wickes paste and what have I got........1.91g!!! Don`t ask me why the result is so different from my earlier one - I don`t have a clue - it`s what the scale showed me. I`m beginning to think that these solids tests mean zilch! There is a lot of chemistry involved with adhesives. Whether it be 19 - 34 - 50 pick a number - it`s pretty meaningless. The ultimate test is burst strength. For me the Wickes and the Polycell are the best all round pastes for workability and tube strength - Period. The tubes already have a very high burst strength, and out of plain curiosity I will soon test them Dags way to see if there is further improvement on the figures. Edited December 19, 2018 by Mixer
Mixer Posted December 19, 2018 Posted December 19, 2018 (edited) well its now bone dry and the result is 18.8%, it`ll come in handy for something but it wont be rocket tubes I wouldn`t be mislead by that - depending on how well your tubes are made, you should be amazed at how strong they are. The burst tests in my Tutorial were from tubes made with this very same tub of paste Edited December 19, 2018 by Mixer
dagabu Posted December 19, 2018 Posted December 19, 2018 I guess the question at hand is whether or not the solids that are present in the adhesive at the time of rolling the tube are enough to create a solid wall and a strong tube? My experience says heck yes! Last night I went back to the way I started rolling tubes but through in a second step which does extend the time by about 15 seconds but not an inordinate amount of time. I just simply roll the tube up, then back it all the way off to that first winding and roll it back up, for some reason, the paper has released some and is at its final full stretch and seems to lay much flattered and I get a thinner tube.
Col Posted December 19, 2018 Posted December 19, 2018 The solids test tells you how much water is in the glue. The more water you put into the paper, the more you have to remove and thats where things get interesting If you roll a tube from dry paper and no glue, every one will be dimensionally perfect and identical.The trick is finding a glue that emulates using no glue
Mixer Posted December 19, 2018 Posted December 19, 2018 (edited) I guess the question at hand is whether or not the solids that are present in the adhesive at the time of rolling the tube are enough to create a solid wall and a strong tube? My experience says heck yes! Last night I went back to the way I started rolling tubes but through in a second step which does extend the time by about 15 seconds but not an inordinate amount of time. I just simply roll the tube up, then back it all the way off to that first winding and roll it back up, for some reason, the paper has released some and is at its final full stretch and seems to lay much flattered and I get a thinner tube. Spot on Dag - when I roll I can`t back up more than a couple of inches as the paper has almost instant bonding and layers will tear - which indicates I have the right amount of paste and tack. Edited December 19, 2018 by Mixer
dagabu Posted December 19, 2018 Posted December 19, 2018 And in my experience becomes impossible to dispense using my methodology. Water it is!
Mixer Posted December 19, 2018 Posted December 19, 2018 The solids test tells you how much water is in the glue. The more water you put into the paper, the more you have to remove and thats where things get interesting If you roll a tube from dry paper and no glue, every one will be dimensionally perfect and identical.The trick is finding a glue that emulates using no glue Hence the need to keep the application of paste to a minimum, whilst still allowing adequate workability
Mixer Posted December 19, 2018 Posted December 19, 2018 And in my experience becomes impossible to dispense using my methodology. Water it is!Good ole water, whack it on Dag
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