Hello everyone,
I'm excited to finally have our machine up and running and winding mandrels, but would really love to hear guys experiences in the resin ratio / viscosity used, and how to control the layer thickness.
For our first pipe I used a low viscosity resin ( around 5000 pc), and put the correct amount of resin per weight of fiber expected into the bath. Within about 4 minutes, the bath was almost empty, and the resin was congealing around the wind, and the strands were " parting" the resin as they were being layed. Is this normal? Is there a special technique, or a particular viscosity resin, or a special amount of tightness in the squeege device people are using to reduce wetout? Is it best to put all in, or put some in, then a little more later ?
Secondly, I generated the G-code for 1 x 60 degree wind, which resulted in 450 passes on a 30cm long, 4.5cm diameter mandrel. Needless to say, 30 minutes in, as the thickness is going past 2mm, I'm wondering what setting I have entered incorrectly?
Is there a trick to setting the layers? Is there any way of knowing how much carbon will be used?
Any experiences greatly appreciated, good or bad
Nick
Replies
Resin Rich Laminate Cure
Get a plastic squeegy. something like the wide plastic ones for putting BONDO on an auto body repair. As the part rotates use this to gather excess resin and return the excess to your mixing cup. When you hit PAUSE, put this reclaimed resin back into the resin bath. I am also going to add a small funnel and plastic tube to the top of the carriage. When I need to refil the resin bath or when I reclaim resin I can put it in the funnel and not have to pause the laminate.
To get full coverage - have a look at the carbon sitting on your spool, measure the smallest, most squashed piece you can see for width, and round down to the nearest mm... thickness generally .008inch or .2mm. and get the diameter correct, or slightly larger than what it is. These three things give you full coverage
Morning,
I have been doing a number of trials with the x-winde3r 2-axis in the UK.
I am struggling to get the layers to completely cover the mandrel i.e the first layer doesn't completely cover the mandrel causing the second layer to be wound onto an nonuniform diameter and resulting in uneven wall thickness throughout the part.
Does any one know how adding additional passes works? Will additional passes continue following the filament offset or will they lay filament on top of the previous passes.
Thanks
Hello Henry,
I've studied the G-code quite a lot now and I guess that the first thing to do is to check that your mandrell is rotating properly. I had issues with the ratio because (in my case at least) the system messes up the ratio if I run it manually.
If thats ok next I would try to set the filament thickness 1-2 mm narrower than it really is. this will add slight overlap to the passes. Of course this will make the surface littele uneven but I dont think that it is that bad. I have run 3mm overlap with 9mm filament and the surface was pretty good.
Adding passes works well too, but you'll have to do it manually so i would recommend doing the trick mentioned above. It's kind of the same thing but computer does the math for you. when adding layers manually you have to change filament offsets manually. Otherwise it should just add new layer on top of the first one.
Hopefully some of these tips work.
-Lauri
Hi,
My company is interested to buy several Xwinders. Anyone has any contact number or email at this company ?
Their web site has been down for a while and I don't have any name or phone number.
My email is j.rennetaud@hiwin.com Company: www.hiwin.com
CONTACT XSALES@XWINDER.COM
Hey Jeremy,
We ended up changing down resins, to a very thin epoxy, I think it was something like 200-400pc. That helped a little, what helped a lot more, was tightening the crap out of the squeegies, and as you said, slowing down the speed.
I've just bought some non perforated release coated heat shrink - not tested yet. I'm hoping to use this heat shrink ( its a full tube so it fits over the whole mandrel like a sock ), and limit the epoxy in the bath to the right ratio, rather than squeege-ing it out with the perforated stuff.
End result I hope is a crystal flat and smooth finish, that I can pull the shrunken heat shrink coat off.
Another issue we've come up against is the mandrel not releasing. We are about to try a machined mandrel 800 long. thinking about using a taper.... any thought on this? or how much needed?
Nick
Hi Nick,
Sorry about the long delay, but how did your experiment with the heat shrink sock go? Was just thinking about adding a sanding block to the bottom to potentially grind it down to size.
Jeremy
Hi mate, we used the heat shrink as a release layer on the mandrel, and for that purpose it worked fine.
We have moved to vacum bagging our stuff, after moving off the winder, and had excellent results.
We also refined our squeege system ( the squeege rollers supplied, are warped, and do not smoothly roll, as we have two rolloers rolling together to act as squeegee, they must be concentric and smooth, so we 3d printed two cylinders, and sanded them flat, and that is our new friction reducing squeegee. We then loaded 12K carbon as the standard size,
Last mod we had to do was remove the roller of the delivery head as It only works with cylinders, and all other non uniform shapes, end up with carbon jamming in the side of the roller at the ends / start of a layer. So we 3d printer a torus shape, and just feed the carbon through it.
Nick
Hi Nick, we have the same problem - carbon strands are jamming the side of the roller. Could you post pictures of your torus shape delivery head installation? Many thanks!
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