After 3 fails its time to ask where i go wrong..

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After 3 fails its time to ask where i go wrong..

After 3 fails its time to ask where i go wrong..

Author	Message
Lester Populaire	L Lester Populaire posted 4 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x Massimiliano - 5/18/2021 2:44:59 AM +x Hanaldo - 4/17/2021 1:17:30 AM A good analogy I heard for it is it's kind of like having a piece of aluminium (your carbon) and trying to reinforce it with a rubber band (your fibreglass). If you take that structure and bend it, the rubber band will bend significantly further than the aluminium but it isn't doing anything to prevent the aluminium from bending. It totally makes sense! But then, what is the purpose of carbon/Kevlar fabric? Mostly damage tolerance
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Massimiliano	M Massimiliano posted 4 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Hanaldo - 4/17/2021 1:17:30 AM A good analogy I heard for it is it's kind of like having a piece of aluminium (your carbon) and trying to reinforce it with a rubber band (your fibreglass). If you take that structure and bend it, the rubber band will bend significantly further than the aluminium but it isn't doing anything to prevent the aluminium from bending. It totally makes sense! But then, what is the purpose of carbon/Kevlar fabric?
	Reply Like 5
jeffrey bres	j jeffrey bres posted 4 Years Ago HOT Post Details
j Group: Forum Members Posts: 42, Visits: 469	Staring to get the hang of it. Still a bit searching for the correct amound of resin but getting better.
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Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Yeh when infusing small parts, the wasteage is significantly higher than wet-layup.
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jeffrey bres	j jeffrey bres posted 4 Years Ago HOT Post Details
j Group: Forum Members Posts: 42, Visits: 469	+x Hanaldo - 4/19/2021 1:12:46 AM Based off your measurements I would estimate you need 700-750g of resin. Fibre:resin ratio should be ~60:40, so you need about 450g of resin (I like to round up) for your 650g of reinforcement. Mesh will take about 700g per square metre. Peel ply is pretty negligible unless you are doing bigger infusions, its about 80g/sqm. By rounding each calculation up, I find you tend to compensate enough to not worry about calculating for peel ply, and hoses, and then depending on infusion size I might factor in a little bit of wastage in the bottom of the pot as well. Ok so if i would say. 40 resin to 60 reinforcements you sayd 450.(lets keep that number for now) plus 400 for he mesh peel and extras. I would have enough. My hoses are short.. that sayd. I was lean in resin im definantly sure. I cant remember making 850 gramms resin. Would be more like 650.. Il keep a closer eye on the resin count. I allways thought i needed less resin with infusing. But ending up using more. Lol. I do get the point though. The extra mesh and all use up a lot. How stupid can i be! Lol
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oekmont	oekmont posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	As you are likely talking about plate stiffness the best solution might be a foam core glass or carbon laminate. This leaves the option to switch to solid glass at some places.
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Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Based off your measurements I would estimate you need 700-750g of resin. Fibre:resin ratio should be ~60:40, so you need about 450g of resin (I like to round up) for your 650g of reinforcement. Mesh will take about 700g per square metre. Peel ply is pretty negligible unless you are doing bigger infusions, its about 80g/sqm. By rounding each calculation up, I find you tend to compensate enough to not worry about calculating for peel ply, and hoses, and then depending on infusion size I might factor in a little bit of wastage in the bottom of the pot as well.
	Reply Like 4
jeffrey bres	j jeffrey bres posted 4 Years Ago HOT Post Details
j Group: Forum Members Posts: 42, Visits: 469	+x oekmont - 4/18/2021 6:26:07 PM Reinforcing carbon with glass is like reinforcing a steel wire with a bungee rope. Before the bungee rope is stretched enough to really produce any significant force, the steel wire will be already way past it's elongation maximum. The combination will still be just as stiff and strong as the steel rope, but with the additional weight of the bungee cord. Either a glass or carbon sandwich might be the solution. Yes you guys told me 3 times now. Is there a better way to keep the costs the same and make a better product? Only glass is to flexible. What is a better layup exept the well known full carbon.
	Reply Like 5
oekmont	oekmont posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	Reinforcing carbon with glass is like reinforcing a steel wire with a bungee rope. Before the bungee rope is stretched enough to really produce any significant force, the steel wire will be already way past it's elongation maximum. The combination will still be just as stiff and strong as the steel rope, but with the additional weight of the bungee cord. Either a glass or carbon sandwich might be the solution.
	Reply Like 5
jeffrey bres	j jeffrey bres posted 4 Years Ago HOT Post Details
j Group: Forum Members Posts: 42, Visits: 469	Another thought. The boat is using around 100cm by 48cm of cloth per layer. With a total of around 650 gramms for the bottom part. (Top is less deu to the cutout.) On top is the peelply and the mesh. how much resin would i need to infuse this? I cant remember how much i put in the parts i did with succes. (Memmory is killing me.) , i think i put way to little resin in. Hand layup i know i allways use 50/50 resin to reinforcement. I dont know how much the mesh needs and the peelply. I infused it front to back(over the long section) Is i cant realy infuse over the short side deu to the mould atm. So i need to bridge 100cm. What would be a good time to aim at to infuse the part? The in2 epoxy is ordered in. So i will wait till that comes. It comes with slow hardner.. Sorry for the questions but my medication spins my head sometimes and i forget or mis understand things what used to be a simple thing for me. Lol. Calculating things is a 100% problem sinds i started on these. Lol Il write it all down. So i dont mess it up again. Lol. Then when it goes wrong i can allways track it back. Before my meds i never had memmory isseus. Please forgive me for giving you a hard time here.
	Reply Like 4