Nylon Bonding Failure
Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp
"I'm pretty sure the powdery layer will be residual nylon". "My recommendation is to run with polyethylene and not use nylon" ???
Curious statements man. Nylon is used as a carrier film for epoxy adhesive films. Untreated Nylon is used as a peel ply. PE is usually thought by most people to be a plastic that won't bond ...
I thought you'd been using this topsheet from Miller for a while now? I'm trying to think about what might have changed.
You haven't mentioned what temperature you've been running on the heater ... I'm guessing 25oC? You said the cure looks OK, but have you flexed the fibre to access the mechanical properties?
If you're going to re-test, it might be worth testing your flame treatment results first. Per video's, dipping them in water and watching the run-off offers a reasonable initial guide to the quality of the result. Testing your technique on base material before switching over to the Nylon, if you are running short, maybe the way to go!
Curious statements man. Nylon is used as a carrier film for epoxy adhesive films. Untreated Nylon is used as a peel ply. PE is usually thought by most people to be a plastic that won't bond ...
I thought you'd been using this topsheet from Miller for a while now? I'm trying to think about what might have changed.
You haven't mentioned what temperature you've been running on the heater ... I'm guessing 25oC? You said the cure looks OK, but have you flexed the fibre to access the mechanical properties?
If you're going to re-test, it might be worth testing your flame treatment results first. Per video's, dipping them in water and watching the run-off offers a reasonable initial guide to the quality of the result. Testing your technique on base material before switching over to the Nylon, if you are running short, maybe the way to go!
Yeah I wasn't convinced by the nylon residue comment. The powder is either from the epoxy or the fibreglass.
In pressing the skis I didn't use the heat blanket, just heated room. Room temp 18C. Tests last night prob similar temp.
First topsheet from miller. Have used fleece backed PBT from Coda in the past.
I have put water on the backs of the topsheets and it seems to bead and run in narrow rivers with a meniscus at the edges. Not encouraging. Seems to be the same after my attempts at flame treatment.
In pressing the skis I didn't use the heat blanket, just heated room. Room temp 18C. Tests last night prob similar temp.
First topsheet from miller. Have used fleece backed PBT from Coda in the past.
I have put water on the backs of the topsheets and it seems to bead and run in narrow rivers with a meniscus at the edges. Not encouraging. Seems to be the same after my attempts at flame treatment.
Don't wait up, I'm off to kill Summer....
Hmm ... just done a bit of searching around and the surface treatment for Nylon appears to be plasma. Per my comment regarding peel ply, Nylons are pretty happy just to go with the flow:
http://www.adhesionassociates.com/paper ... 950072.pdf In the first few pages, it makes the point that Nylon and Epoxy form a chemical bond. So, if we are talking apples and apples, you should be getting a better result.
If this takes us back to the epoxy and you discount blush ... then you have to consider whether the viscosity of the epoxy is an issue, as it doesn't alter much, due to it being an ambient cure. You could get a feel for whether this is the issue by running a test using ordinary super glue - it may not be the right adhesive, but the result should come quickly. If you get a good initial bond, without abrading the surface, then you may need to think about whether the temperature of these trials is having an impact. Lower temp, higher viscosity, less penetration into the substrate.
Assuming a positive result from the super glue, I would lightly abrade the topsheet, clean with solvent and adjust the first 10 - 15 mins of the cure cycle (I'm not clear from the research whether particular solvents alter the surface chemistry of the Nylon, something for later) So, if it's currently 6 - 12 hours at 25oC, I would run 30oC for the first 30 mins. If you temperature probe within the ski to set this up, as I'm trying to suggest 15 mins at 30oC on a trial basis - but the manufacturer should know more about how temperature will effect viscosity and how sensitive the cure cycle is to variation.
Re: Blush/Bloom, does the manufacturer say it is a no blush formula? All the photo's I've seen look very similar to your result.
http://www.adhesionassociates.com/paper ... 950072.pdf In the first few pages, it makes the point that Nylon and Epoxy form a chemical bond. So, if we are talking apples and apples, you should be getting a better result.
If this takes us back to the epoxy and you discount blush ... then you have to consider whether the viscosity of the epoxy is an issue, as it doesn't alter much, due to it being an ambient cure. You could get a feel for whether this is the issue by running a test using ordinary super glue - it may not be the right adhesive, but the result should come quickly. If you get a good initial bond, without abrading the surface, then you may need to think about whether the temperature of these trials is having an impact. Lower temp, higher viscosity, less penetration into the substrate.
Assuming a positive result from the super glue, I would lightly abrade the topsheet, clean with solvent and adjust the first 10 - 15 mins of the cure cycle (I'm not clear from the research whether particular solvents alter the surface chemistry of the Nylon, something for later) So, if it's currently 6 - 12 hours at 25oC, I would run 30oC for the first 30 mins. If you temperature probe within the ski to set this up, as I'm trying to suggest 15 mins at 30oC on a trial basis - but the manufacturer should know more about how temperature will effect viscosity and how sensitive the cure cycle is to variation.
Re: Blush/Bloom, does the manufacturer say it is a no blush formula? All the photo's I've seen look very similar to your result.
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MontuckyMadman
- Posts: 2395
- Joined: Fri Jun 20, 2008 9:41 pm
That nylon sticks to everything.
I can get it to stick to polyester foil film that nothing else sticks too.
I just layed a bunch up last night, it tears before it peels in most cases.
Are you sure your using the correct side of the material?
There is a peel ply.
Silly yes, wouldn't be the first time however if I recall.
Has to be the room temp cure or the epoxy itself.
Cant stick to UHMW and not nylon.
Lay up some base samples???
Put that blanket back in the press and press a sample with heat, and then don't take the blanket out.
Is the resin maybe possibly a polyester base? Just a shot in the dark.
That nylon bonds very well with epoxy, does that guys seriously know what he is talking about?
You can flame it. In my test the stuff I flamed adhered better straight out of the press but after a week the bond was indeterminable.
I can get it to stick to polyester foil film that nothing else sticks too.
I just layed a bunch up last night, it tears before it peels in most cases.
Are you sure your using the correct side of the material?
There is a peel ply.
Silly yes, wouldn't be the first time however if I recall.
Has to be the room temp cure or the epoxy itself.
Cant stick to UHMW and not nylon.
Lay up some base samples???
Put that blanket back in the press and press a sample with heat, and then don't take the blanket out.
Is the resin maybe possibly a polyester base? Just a shot in the dark.
That nylon bonds very well with epoxy, does that guys seriously know what he is talking about?
You can flame it. In my test the stuff I flamed adhered better straight out of the press but after a week the bond was indeterminable.
sammer wrote: I'm still a tang on top guy.
I glued some nylon topsheet to a piece of wood with superglue.
After 5-10 minutes I had to lever up with a screw driver and use a lot of pull to get it to come up. Sometimes get the screw driver wedged back in. The nylon also tore when trying to pull it up (as you say Montucky) and there is some plywood on the bonding surface stuck on with glue. Bonding much better than with epoxy.
I did abrade the back of a piece with 80 grit and glued to wood with superglue also. It bonded better than the epoxy, but not quite as well as the other superglued piece with factory abrasion (it wasn't left for the glue to set for as long though as I was going to work).
Probably best to do a heat cured trial with my old epoxy then if it seems to glue well will clean and sand the upper glass layer on these skis and repress using heat and old epoxy and a new topsheet.
After 5-10 minutes I had to lever up with a screw driver and use a lot of pull to get it to come up. Sometimes get the screw driver wedged back in. The nylon also tore when trying to pull it up (as you say Montucky) and there is some plywood on the bonding surface stuck on with glue. Bonding much better than with epoxy.
I did abrade the back of a piece with 80 grit and glued to wood with superglue also. It bonded better than the epoxy, but not quite as well as the other superglued piece with factory abrasion (it wasn't left for the glue to set for as long though as I was going to work).
Probably best to do a heat cured trial with my old epoxy then if it seems to glue well will clean and sand the upper glass layer on these skis and repress using heat and old epoxy and a new topsheet.
Don't wait up, I'm off to kill Summer....
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MontuckyMadman
- Posts: 2395
- Joined: Fri Jun 20, 2008 9:41 pm
Falls, a couple things;
Have you talked to Vince? What did he say?
Just for shits and giggles try a test flipping the top sheet so the other side is down. I know rough side/smooth side but what have you got to loose at this point.
I feel your pain, I hate it when stuff just peels apart.
sam
Have you talked to Vince? What did he say?
Just for shits and giggles try a test flipping the top sheet so the other side is down. I know rough side/smooth side but what have you got to loose at this point.
I feel your pain, I hate it when stuff just peels apart.
sam
You don't even have a legit signature, nothing to reveal who you are and what you do...
Best of luck to you. (uneva)
Best of luck to you. (uneva)
I sent a message to Craig at Miller last night but haven't heard back as yet.
Shiny side doesn't bond at all well with superglue.
I tried bonding with some 5 minute epoxy to the rough side and the bond is better than the laminating stuff but still not great, not as good as superglue.
Montucky - bond to UHMWPE seems very good. It is weird
Shiny side doesn't bond at all well with superglue.
I tried bonding with some 5 minute epoxy to the rough side and the bond is better than the laminating stuff but still not great, not as good as superglue.
Montucky - bond to UHMWPE seems very good. It is weird
Don't wait up, I'm off to kill Summer....
Using the old epoxy might be a tricky. The Tg for the new epoxy will be below the cure temperature of the old. Not sure what the actual effect will be long term.
If you don't want to use the new epoxy to attach the topsheet until you have conducted further tests, have you thought about using gorilla glue - its a polyurethane. SD has tested it, so you should be on safe ground. It's not the only option: http://www.reltekllc.com/adhesives-for-nylon.html , but the test results from Gorilla should come quicky and it won't mind being put in the press and put through a 25oC heat cycle. If your workspace is anything like mine, you'll have options to hand. Anyway, I think an approach like this will ensure you stay closer to the intended result without too many unexpected surprises.
If you don't want to use the new epoxy to attach the topsheet until you have conducted further tests, have you thought about using gorilla glue - its a polyurethane. SD has tested it, so you should be on safe ground. It's not the only option: http://www.reltekllc.com/adhesives-for-nylon.html , but the test results from Gorilla should come quicky and it won't mind being put in the press and put through a 25oC heat cycle. If your workspace is anything like mine, you'll have options to hand. Anyway, I think an approach like this will ensure you stay closer to the intended result without too many unexpected surprises.
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MontuckyMadman
- Posts: 2395
- Joined: Fri Jun 20, 2008 9:41 pm
Craigs the graphics guy not materials.
Ill save you the wait as I have done this myself.
Vi nce will tell you the only ti.e this stuff doesn't bond is when there isn't enough stickum.
He's never lqminated anything but been doin buis with those who have for 20 years.
Maybe it is the viscosity and it does t stay on there for some reason.
Seems so weird it qould stick to the worlds most I ert substance and not some topsheet.
I think tue real trick would be t o find other stuff it does not stick to.
Try other nylons.
They are all type 6 thermoplastics so try some other raw nylons.
Ill save you the wait as I have done this myself.
Vi nce will tell you the only ti.e this stuff doesn't bond is when there isn't enough stickum.
He's never lqminated anything but been doin buis with those who have for 20 years.
Maybe it is the viscosity and it does t stay on there for some reason.
Seems so weird it qould stick to the worlds most I ert substance and not some topsheet.
I think tue real trick would be t o find other stuff it does not stick to.
Try other nylons.
They are all type 6 thermoplastics so try some other raw nylons.
sammer wrote: I'm still a tang on top guy.
I had thought of that Rich. The room temp epoxy can be post cured at up to 80C, so it would soften then be tougher when cooled. However I am not sure what would occur at the interface between old epoxy and new epoxy when heated.
I think I will sand the top of the skis and then repress with a wood veneer and room temp epoxy. I have made another pair with wood veneer and this room temp epoxy and they seem pretty solid.
Other things I am thinking about are nylon's ability to absorb water and maybe this is affecting the bond at the surface of the plastic (releasing water when exposed to the exothermic reaction of the epoxy adjacent).
Or poor burning of the propane leading to soot accummulation when flaming. Apparently soot has been used in the past as a mold release. I think you would see the black soot though and the topsheet bonding side looked clean when originally pressed.
I was looking forward to the ease of finishing a plastic topped ski compared to wood veneer
I think I will sand the top of the skis and then repress with a wood veneer and room temp epoxy. I have made another pair with wood veneer and this room temp epoxy and they seem pretty solid.
Other things I am thinking about are nylon's ability to absorb water and maybe this is affecting the bond at the surface of the plastic (releasing water when exposed to the exothermic reaction of the epoxy adjacent).
Or poor burning of the propane leading to soot accummulation when flaming. Apparently soot has been used in the past as a mold release. I think you would see the black soot though and the topsheet bonding side looked clean when originally pressed.
I was looking forward to the ease of finishing a plastic topped ski compared to wood veneer
Don't wait up, I'm off to kill Summer....
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catalystsnowboards
- Posts: 7
- Joined: Wed Apr 20, 2011 2:02 pm
Was your printed topsheet backed up with a epoxy ink layer? or did you just have a subbed graphic on a clear nylon?
We have done plenty of stuff with a clear nylon subbed and it works great, but on a few occasions when we have flooded with a epoxy ink our bond through the ink layer has been poor. Which could be attributed to numerous things.
We have done plenty of stuff with a clear nylon subbed and it works great, but on a few occasions when we have flooded with a epoxy ink our bond through the ink layer has been poor. Which could be attributed to numerous things.