When vacuum infusion is done to the hull sides in molds... how is the cloth layups done before bagging it and starting the infusion? I'm thinking about what is keeping the cloth in place on the vertical parts... is there some kind of temporary adhesion and if so, what's that product called and how is it applied? 🙂
Spray glue! There are lots of products people use - the most common is 3M "Super 77" spray contact adhesive. There are more composites-specific options that work better and are resin soluble. The key to success is using just enough to hold things together and not too much. Excess spray glue is one of the big problems people have with infusions.
Do I understand your weight estimate spreadsheet correctly that you estimated 150gsm of resin for uptake in the balsa? I’m doing an infusion soon and not finding a ton of great resources on standard resin uptake for core materials…
No - I'm pretty sure that's a mistake! Probably a cell I forgot to delete when copy/paste-ing a new sheet and switching from metric to imperial. The balsa should take up way more resin that that - the 27oz/yard is like 900g/m^2. I always assume 300-500g/m per face for resin uptake in low density foam and balsa is probably worse.
@@ExploreComposites I found a really good way to prevent that…. You just have the resin gel before the infusion completes! :( Very effective in reducing uptake of resin…. Had to consult the “problems with infusion” article! Sure enough, there it is. A second shot “kind of” saved the part, but definitely way less than ideal. Infusion, what a great process to screw things up with! I think I’m batting .100 or less with it
You're right - while balsa is very good mechanically it is still wood and so it has wood-problems. Lots of balsa issues came from poor core bonding of hand-laid parts (like boats) - where if water got in it would just soak across large areas. When it's bad - it's terrible! With infusion, all the core cuts are filled with resin and water intrusion becomes much less of a problem. The down-side is that it soaks up more resin than foam and so is even heavier. Balsa is less commonly used than it used to be, but for things that aren't used in the water and where excellent core compression properties are required I think it is worth a look.
You would be better off using 316 L SST SCREEN IN A SNDWICH LAYERS IT IS VERY STRONG AND NO ROT IF YOU ARE CHEEP YOU COULD USE ALUM COPPER BRASS OR PLASTIC TRY THAT OUT LET ME KNOW WHAT YOU THINK . WHY IS WIRE MESH USED IN CEMENT SLABS ????
When vacuum infusion is done to the hull sides in molds... how is the cloth layups done before bagging it and starting the infusion? I'm thinking about what is keeping the cloth in place on the vertical parts... is there some kind of temporary adhesion and if so, what's that product called and how is it applied? 🙂
Spray glue! There are lots of products people use - the most common is 3M "Super 77" spray contact adhesive. There are more composites-specific options that work better and are resin soluble.
The key to success is using just enough to hold things together and not too much. Excess spray glue is one of the big problems people have with infusions.
Do I understand your weight estimate spreadsheet correctly that you estimated 150gsm of resin for uptake in the balsa?
I’m doing an infusion soon and not finding a ton of great resources on standard resin uptake for core materials…
No - I'm pretty sure that's a mistake! Probably a cell I forgot to delete when copy/paste-ing a new sheet and switching from metric to imperial. The balsa should take up way more resin that that - the 27oz/yard is like 900g/m^2. I always assume 300-500g/m per face for resin uptake in low density foam and balsa is probably worse.
@@ExploreComposites I found a really good way to prevent that…. You just have the resin gel before the infusion completes! :(
Very effective in reducing uptake of resin….
Had to consult the “problems with infusion” article! Sure enough, there it is. A second shot “kind of” saved the part, but definitely way less than ideal.
Infusion, what a great process to screw things up with! I think I’m batting .100 or less with it
If BALSA IS SO GOOD THEN WHY DOES TI FAIL SO OFTEN IT ROTS
You're right - while balsa is very good mechanically it is still wood and so it has wood-problems. Lots of balsa issues came from poor core bonding of hand-laid parts (like boats) - where if water got in it would just soak across large areas. When it's bad - it's terrible!
With infusion, all the core cuts are filled with resin and water intrusion becomes much less of a problem. The down-side is that it soaks up more resin than foam and so is even heavier. Balsa is less commonly used than it used to be, but for things that aren't used in the water and where excellent core compression properties are required I think it is worth a look.
@@ExploreComposites Why not use fiber glass honey comb it does not rot balsa has very poor shear strength pan is poor in end grain compression
You would be better off using 316 L SST SCREEN IN A SNDWICH LAYERS IT IS VERY STRONG AND NO ROT IF YOU ARE CHEEP YOU COULD USE ALUM COPPER BRASS OR PLASTIC TRY THAT OUT LET ME KNOW WHAT YOU THINK . WHY IS WIRE MESH USED IN CEMENT SLABS ????