Comments welcome on this one:
http://sketchup.google.com/3dwarehouse/ ... revstart=0
Fibre Impregnator
Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp
There are a ton of variables, but just as an example of what a commercially available impregnation equipment consists of:
http://www.waeco1.com/
http://www.waeco1.com/
Just building skis.
The machine works as well - it hits its mark.
The fibre is heated before it is dipped, the epoxy is held at a constant temp - indirect heating. The dipped fabric is nipped and compacted as it is moves through the final set of rollers. The accuracy of the final set of rollers is key - they could have been bigger, but cost was an issue. The machine is small and compact, structure is built from left over cat-track and mdf.
The machine works as well - it hits its mark.
The fibre is heated before it is dipped, the epoxy is held at a constant temp - indirect heating. The dipped fabric is nipped and compacted as it is moves through the final set of rollers. The accuracy of the final set of rollers is key - they could have been bigger, but cost was an issue. The machine is small and compact, structure is built from left over cat-track and mdf.
Sorry if I sounded obtuse earlier - I do this for a living so all I'm going to be able to do is poke holes/give you some talking points to consider. Sounds like this is already built? I apologize in advance if these seem pointed.
This is catalyzed epoxy correct? What temperature will the resin be? Any concerns of exotherm potential?
What are you going to use to separate the finished product on the roll?
What weight of fabric are you targeting?
How much pressure do you anticipate needing?
Do you have a target resin content? How much variation is acceptable?
One concern of a solventless resin bath is segregation of epoxy constituents - have you seen this issue and any plans to mitigate?
Are you able to maintain constant tension on the fabric?
What is the anticipated line speed?
Again, sorry for being obtuse I just want to be sure you are successful!
Damon
This is catalyzed epoxy correct? What temperature will the resin be? Any concerns of exotherm potential?
What are you going to use to separate the finished product on the roll?
What weight of fabric are you targeting?
How much pressure do you anticipate needing?
Do you have a target resin content? How much variation is acceptable?
One concern of a solventless resin bath is segregation of epoxy constituents - have you seen this issue and any plans to mitigate?
Are you able to maintain constant tension on the fabric?
What is the anticipated line speed?
Again, sorry for being obtuse I just want to be sure you are successful!
Damon
Hi Damon,
No worries - I had it in mind that you might be in the biz, thanks for taking an interest )
Its currently a working prototype, so any pointers at this stage would be appreciated. The following is the best information I can give ... I hope I understood everything correctly.
- Catalyzed epoxy, held at 25oC. Potential for exotherm - YES. Plastic reservoir (container used). Metal in the final build.
- It doesn't produce a roll, each length is cut and used. No carrier involved, found to be too tricky to implement.
- Fabric 800g tri-axial
- Pressure, while compacting?
- The target resin content is currently being re-assessed in light of new results. Variation will be dependent on final specification and treatment of the core material prior to use. Core cross-section suggest that tooling is not creating any issues. Expected variation, difficult to say. The fabric is spot on and I'm on the resin rich side of things. Final results once the product has been built suggest difference across set of skis of approximately 5-10g.
- Not seen segregation, but it sounds like I need to research this.
- Fabric is under constant tension, the fabric is partially driven, mostly drawn through the rollers using a small motor.
- Line speed is about 0.75mtr per minute.
Thanks again for looking at this!
No worries - I had it in mind that you might be in the biz, thanks for taking an interest )
Its currently a working prototype, so any pointers at this stage would be appreciated. The following is the best information I can give ... I hope I understood everything correctly.
- Catalyzed epoxy, held at 25oC. Potential for exotherm - YES. Plastic reservoir (container used). Metal in the final build.
- It doesn't produce a roll, each length is cut and used. No carrier involved, found to be too tricky to implement.
- Fabric 800g tri-axial
- Pressure, while compacting?
- The target resin content is currently being re-assessed in light of new results. Variation will be dependent on final specification and treatment of the core material prior to use. Core cross-section suggest that tooling is not creating any issues. Expected variation, difficult to say. The fabric is spot on and I'm on the resin rich side of things. Final results once the product has been built suggest difference across set of skis of approximately 5-10g.
- Not seen segregation, but it sounds like I need to research this.
- Fabric is under constant tension, the fabric is partially driven, mostly drawn through the rollers using a small motor.
- Line speed is about 0.75mtr per minute.
Thanks again for looking at this!
What resin will you be using? Do you know the viscosity at 25C? I think you'll be safe with most the elevated cure systems we use - but I'd build in some kind of drain or something so that if you notice that "glassy" appearance, you can dump it. Best way to control a runaway reaction is to give it as much surface area as possible - spread it thin on a polyethylene sheet or something.
Yeah at <1m/min there isn't going to be much agitation in the pot, I'd definitely consider adding something to stir it around a bit. This will also help with exotherm potential. Given the relatively simple resins we use, having components separate is probably unlikely - but if you're using something exotic with fillers or differing molecular weight resins, it might be more of a concern.
As far as pressure, this will be dependent on the viscosity of the resin. All I know is for a 800gsm fabric, with say 40% resin content? You're going to need to shove in a lot of resin. I'd over design this.
On tension - I didn't consider triax. The +/-45 fibers are going be tricky. Spend extra on a very precise tension controller.
Yeah at <1m/min there isn't going to be much agitation in the pot, I'd definitely consider adding something to stir it around a bit. This will also help with exotherm potential. Given the relatively simple resins we use, having components separate is probably unlikely - but if you're using something exotic with fillers or differing molecular weight resins, it might be more of a concern.
As far as pressure, this will be dependent on the viscosity of the resin. All I know is for a 800gsm fabric, with say 40% resin content? You're going to need to shove in a lot of resin. I'd over design this.
On tension - I didn't consider triax. The +/-45 fibers are going be tricky. Spend extra on a very precise tension controller.
Another thing I just thought about... I'm not sure about this, but if you're impregnating at essentially room temperature, wouldn't the viscosity of the resin be low enough to flow back out? I guess you could freeze it right away?
Yeah on the triax it will be interesting. We'll see how much tension you'll need I guess. I'm just concerned you'll get "scissoring" of the diagonal fibers.
Yeah on the triax it will be interesting. We'll see how much tension you'll need I guess. I'm just concerned you'll get "scissoring" of the diagonal fibers.