I’ve put things up there. It’s a bit clunky right now, but it’ll get better. Unless things change, I’ve run out of time for today, so here are the state of things:
-Method does nothing.
-Mix ratio is currently only calculated by weight.
-Regardless of the Result Type, only Weight is calculated.
-Regardless if the “Also show US Units” is checked or not, it shows US units.
-Haven’t had a chance to look at any anomalies, (i.e. Thickness), but some better calculations are pending.
Looks like I’m using 2.6 for E-Glass. Attached is a snapshot of records in the “reinforcements” table. (Such as it is.) You’ll see a lot of holes in this data! I need help! Plus, I’m sure there needs to be more mechanical properties, of which I’m not sure these I have are useful, (they’re basically just there to remind me of what I’ll need to have at some point).
Notice the K1 & K2 factors. Not sure what I’m going to do about getting values for, say Basalt? Plus the density of the other values, etc.
I don’t know if this is what you’re thinking of exactly, but infusion Mesh was a bit of a problem… It adds to the total resin required for production, but it’s thickness is then stripped, so the production thickness of the resin it absorbs is now subtracted from the thickness of the part.
Herman, I agree with you about the units. :nuts: (Haven’t had time to do the math, just yet.) That said, it’s a clear sign Adam is brilliant. Not easily to make those conversions without having to struggle.
Perusing the equation, I think I see maybe where I’ve made my error, but I’m in composites mode today, not computer mode.
Say, have you looked at things lately?? http://black-lab.com/resin/ Still some goobered up elements of the user interface, etc., but it’s getting closer I think. Somehow I’ve got to get good values in the DB tables.
Ok, got the thickness calculation fixed. Essentially didn’t multiply a factor by the surface area. I’ve tweaked some DB values, and made some assumptions: I’m assuming hybrids are 50:50, so their SG is the mean. Right?
I’ve added a weight calculation and tested it against my part. My part with flanges is 1.394 kg, it calculates it should be: 1.332 kg, so it’s in the ball park. I’ve added a part surface area to get the end part weight.
I’m getting a different weight calculation than your tool is calculating. Yours is predicting a value that is a lower than the theoretical weight. Would you like to see the math?
Did you mic the thickness of your part? From the thickness you can calculate the theoretical Vf% (assuming no porosity). If you weigh the fabric before the layup you can then weigh the part after infusion to determine the weight of the resin in the part. Using the thickness and weight of each part you can calculate the Vf% AND the porosity of the laminate.
Adam, yes show the math. I think I just used weight of reinforcements + resin. That sounds logical, right?
I used a dial caliper to measure the thickness.
Another thing… On my part I use a Soric SF3 core, which apparently compresses 15% under 0.8 bar. I’m under the assumption the compression is linear? So, at 1 bar, I’m really at 2.43mm??, (can’t remember exactly). I’ve added logic, (not much data yet), to deal with this thickness. What do you think?
I did an infusion test on Monday and used the calculator’s results. Not too great. I found myself scrambling to make a last minute batch, as I was short by ~120g. My part is ~0.33 sqM.
That said, I’m still new to infusion. It wigs me out to be running out of resin before it hits the other side. So, I guess I’m asking an infusion philosophical question: Should I have trusted the calculation and clamped it before the resin front hit the receiver? What is the conventional wisdom in this?
Jap, you should mic the final thickness of your test. You can use this help resolve some of the issues. If the part is thicker than predicted then the Vf% is lower than the mystery number predicted.
Also, is the thickness consistent in the part? Is the side closest to the inlet thicker than the outlet sided?
Did you weigh the fabric before the infusion test? After infusion?
Dang, I see that I forgot to post the math for weight calculation. I’ll do that soon.
On the sides, (mid way), it’s very close to the calculation. Inlet is .010" thicker and outlet is .010" thinner. I’m using a slide thickness gage. I could be off. I can tell there is a slight variance though. I didn’t weigh the material beforehand.
That said, I think I have found much of my discrepancy: Embarrassed to say… I added a strip of peel ply and mesh that I didn’t account for. :nuts: (I’ve been using Soric as the flow medium.) Adding these values in the program changes the matrix total to ~807g (+100). So, in theory I’m now off ~22g.
But this is all hogwash to be honest. I didn’t have a good uptake figure for peel ply. The nearest figure I could find was 300gsm. I have no idea if that’s reasonable or not. If it is, then I’m close. Airtech seems to be a major supplier, but the specs don’t say what the uptake is.
Saying “I’m off” is pretty silly when I don’t understand at this stage what’s enough! I’ve got vague concepts, like: “Collecting resin in the catch pot is too much”, and “Stopping before wetting out all the material is too little.” How do you define “Just right”?
I’ve changed the program and added a control to each stack line item to set a surface area which might be different from the total casting surface area, which is the case for strips of peel ply, and mesh.
You’ll also see you can now use calculated values for input ++.
++ And a word for those with malicious intent: :evil: Be aware, I’ve created this feature properly… I know the typical, Chuck-Sixpack, programmer wannabe, will not implement this feature properly, and allow you to break-in. Don’t even bother trying, the door is closed!
(Sorry, the fewer vermin I have to pull out of my server, the better.)
Also keep in mind that the smaller the scale, the more difficult it is to predict resin usage, even if you have exact figures for your materials. Bridging, non-exact cutting, variations in the materials, piping, relaxation of the fabric at the infusion point, all factors that can vary the results.
This sort of calculations is VERY useful for larger infusions. Last time I did a 290 kg infusion (some 80 gallons or so) and it is very useful to know the resin usage within 10 kgs or so. (and we really do not care about that last 10 kgs…)
My friend recently did a 30.000 kg infusion. (give or take 1000 kgs…)
I think I just used weight of reinforcements + resin. That sounds logical, right?
I found myself scrambling to make a last minute batch, as I was short by ~120g. My part is ~0.33 sqM.