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Andre Hartmann
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I am doing high gloss and sattin finish carbon fiber sheets using glass plates and aluminium sheets as negativ surface.
While the satin sheets just fall of the alumium after cureing the other ones stuck to the glass and have to be peeled off.
In the beginning, more renewed layers help, but at some point the point is reached that the sheets can only be removed with fine fine cracks in the surface because they are that strongly stuck to the glass plate.
The problem arises with increasing age of the release agent, however regardless of the specified shelf life?! The last bottle of 'Easy-Lease Chemical Release Agent' was ordered on March 22. Batch sticker says: ELRA-01 4173-19
With this bottle the problem occurred from the beginning. Of course the surface was first cleaned with Easy-Lease Mould Cleaner.
I know glass as surface can be tricky but over the last 1 1/2 years I also got many remarkables results using 'xc110' in combination with the 'Easy-Lease Chemical Release Agent'.
But all sheets with cracks in the surface cannot be used for further production in my company, they have to be sorted out. This is extremely annoying in terms of the value of the wasted material and especially the work involved.
I hope you can help.
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Warren (Staff)
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HI,
Sorry to hear you've been having problems. Checked the batch number and the ELRA is still well within date, so unless its been opened or the cap not tightened fully, I would still expect it to work well.
A few things I don't quite understand from your description - probably lost a little in translation.
You mention a satin and gloss finish sheets - you mention the satin sheets release fine but not the gloss? Is this with same release agent batch and same application etc?
When you say the release properties fall away in time, is this after repeated applications of release agent?
As you say, Glass can be difficult to work with. However, a good coating of EasyLease should release very well. It could be possible that repeated applications are building up too much and then either coming away or not working properly. That can happen on normal mould surfaces, the build up can feel slightly tacky and just not work as well. Usually an acetone or Mould cleaner wipe down to remove all traces and starting from scratch will help.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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Andre Hartmann
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Group: Forum Members
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Hi Warren,
the satin sheets are made using an aluminium plate, the glossy ones are made using a glass plate. Yes the satin sheets release fine, the gloss ones not. Yes the same release agent batch and same application etc is used.
On the glass plate the release properties fall away with every cure cycle. With the the new and named batch of realse agent I did start from scratch and used mould cleaner to wipe down the left traces and applied 6 new layers. However, the result was as described.
I was still able to work with the last batch of release agent until three or four weeks ago, although I had to renew the layers more often (like 3 or 4 new layers after every cure cycle), I was still able to release the sheets without damaging the surface as described above. Than the release properties fall away extremly, which is why I have ordered a new bottle.- The last batch was: ELRA-05 12113/18
Is it possible to find out how old each bottle is? I would be interested to know how far the dates are apart. As the last time the problem occurred, a new bottle of the release agent solved the problem.
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Warren (Staff)
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Group: Administrators
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Ok so its as much an issue with glass as it is the release agent, as its working fine on aluminium.
For pre-preg, I would expect release properties to fall away each time. Typically at least one recoat is needed on more aggressive processes like infusion or pre-preg.
The bottle you originally mentioned was from 17/10/19 and the one in the post above is 21/12/18 so almost a year apart and your newer one is almost a year newer.
I would certainly expect the newer one to perform better than the old batch - all things being equal.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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Andre Hartmann
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Group: Forum Members
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Visits: 56
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Just replaced the glass plate, again 6 layers of easy lease and still the same problem. So wouldn't say it is an issue with the glas.
No noticeable difference between the old and new batch. The newer one by the way is a 100ml plastic bottle, the old one was a 500ml metal can, but I guess this shouldn't make any differnce.
Any further ideas?
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Hanaldo
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Potentially an application issue. How heavy/wet are you putting on each coat? How long are you waiting between coats?
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John Hansen
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While the issue seems to be the application of the release agent or the release agent itself, I might suggest that heating (of freezing) the glass after the CF is cured may assist in the release of the CF composite from the surface of the glass.
The coefficient of expansion of the glass and the CF are close to each other but the resin in the CF composite sheet will shrink or expand slightly more at the surface than the glass sheet. I think this may be worth trying as it is rather easy using a common heat gun on the glass side only. Lay the CF down onto a flat metal surface to act as a heat sink that will keep the CF at room temperature while heating the glass.
A Lifelong Learner
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Andre Hartmann
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Group: Forum Members
Posts: 8,
Visits: 56
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@ Hanaldo
I apply the release agent exactly as specified, I put thin coats on and wait about 15 mins or longer between them. As said before the problem has only just started with the new batch of the release agent. Until the old one was outdatet it worked just fine.
@John Hansen
Thanks for your advice. Tried it, unfortunately it makes no difference. :-(
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Matt (Staff)
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Hi Andre, We too use glass sheets and the XC110 prepreg to produce perfect finish carbon fibre sheets; our manufacturing department uses this combination every day to produce 20+ sqm of sheet so this is a combination we know very well. We have no reported issues with Easy-Lease and have not experienced any problems ourselves, however, to rule that out and get to the bottom of this as quickly as possible for you I think it's probably a good idea to send you a new bottle out of the very latest batch. I'll also check which batch we're using in manufacturing at the moment. I can see that Warren has mentioned this already but it will probably be helpful to you if I reiterate our own application process for our glass sheets. Our life-cycle looks like this: - We use brand new, standard toughened glass sheets (with NO special coatings, UV filters or other treatments)
- New sheets are cleaned with mould cleaner to remove any residual contaminants from the manufacturing process.
- We use lint free cloths to apply Easy-Lease chemical release agent. We normally use 2 small pads, one wet with release agent and the other clean. As we wipe on gently with the wet one, we wait a few seconds for the solvent to evaporate and then very gentle wipe over with the dry one to smooth out the application. This is to prevent any smears.
- We wait 15-20 mins and repeat the above step. We apply 5 applications in total, to a new sheet.
- We wait several hours before using the glass sheet in production.
- Release will be perfect, the carbon will just peel away from the glass.
- We then re-apply the one application of release agent, in the same way.
- The cycle continues of re-applying once each release.
Using this process we have never had a sheet stick in my memory (more than 8 years of production like this) and our carbon fibre sheets have a completely perfect surface finish. So, I'm sure we can help you to get the same! The only things that affect the release are as follows, and all of these factors are KNOWN to affect the release so they all need thinking about: - The release agent: Is it suitable? (Easy-Lease is). Is it in date? Has it been stored correctly? (lid tightly sealed).
- The glass sheets: Are they plain, toughened glass or are they treated or coated in some way?
- The cure: Has the prepreg fully cured before you try to release it. If it's not fully cured, it will really stick to the glass sheets, no matter how good the release agent it.
So, you'll notice that the one we've not explored here is #3, the level of cure. As you'll know, aluminium is a great conductor of heat. Your aluminium sheets are also possibly quite thin. Both these things mean that the prepreg on the aluminium sheets will get the heat from the oven very quickly. Glass on the other hand is not such a great conductor of heat and your sheets are probably thicker too meaning it's possible that in the same oven the prepreg for the aluminium sheets is being more fully cured than the prepreg on the glass sheets. We'll arrange to send some new release agent out to you to rule that one out. I suggest you look into the glass you're using to check there's nothing strange about that and also check your cure cycle to ensure you're achieving a FULL cure on the prepreg. There's no harm in curing for longer so that's an easy one to rule out too. The answer can only be one of these three things. All the best, Matt
Matt StathamEasy Composites / Carbon Mods - Technical Sales
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Matt (Staff)
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Group: Forum Members
Posts: 680,
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+xHi Andre, We too use glass sheets and the XC110 prepreg to produce perfect finish carbon fibre sheets; our manufacturing department uses this combination every day to produce 20+ sqm of sheet so this is a combination we know very well. We have no reported issues with Easy-Lease and have not experienced any problems ourselves, however, to rule that out and get to the bottom of this as quickly as possible for you I think it's probably a good idea to send you a new bottle out of the very latest batch. I'll also check which batch we're using in manufacturing at the moment. I can see that Warren has mentioned this already but it will probably be helpful to you if I reiterate our own application process for our glass sheets. Our life-cycle looks like this: - We use brand new, standard toughened glass sheets (with NO special coatings, UV filters or other treatments)
- New sheets are cleaned with mould cleaner to remove any residual contaminants from the manufacturing process.
- We use lint free cloths to apply Easy-Lease chemical release agent. We normally use 2 small pads, one wet with release agent and the other clean. As we wipe on gently with the wet one, we wait a few seconds for the solvent to evaporate and then very gentle wipe over with the dry one to smooth out the application. This is to prevent any smears.
- We wait 15-20 mins and repeat the above step. We apply 5 applications in total, to a new sheet.
- We wait several hours before using the glass sheet in production.
- Release will be perfect, the carbon will just peel away from the glass.
- We then re-apply the one application of release agent, in the same way.
- The cycle continues of re-applying once each release.
Using this process we have never had a sheet stick in my memory (more than 8 years of production like this) and our carbon fibre sheets have a completely perfect surface finish. So, I'm sure we can help you to get the same! The only things that affect the release are as follows, and all of these factors are KNOWN to affect the release so they all need thinking about: - The release agent: Is it suitable? (Easy-Lease is). Is it in date? Has it been stored correctly? (lid tightly sealed).
- The glass sheets: Are they plain, toughened glass or are they treated or coated in some way?
- The cure: Has the prepreg fully cured before you try to release it. If it's not fully cured, it will really stick to the glass sheets, no matter how good the release agent it.
So, you'll notice that the one we've not explored here is #3, the level of cure. As you'll know, aluminium is a great conductor of heat. Your aluminium sheets are also possibly quite thin. Both these things mean that the prepreg on the aluminium sheets will get the heat from the oven very quickly. Glass on the other hand is not such a great conductor of heat and your sheets are probably thicker too meaning it's possible that in the same oven the prepreg for the aluminium sheets is being more fully cured than the prepreg on the glass sheets. We'll arrange to send some new release agent out to you to rule that one out. I suggest you look into the glass you're using to check there's nothing strange about that and also check your cure cycle to ensure you're achieving a FULL cure on the prepreg. There's no harm in curing for longer so that's an easy one to rule out too. The answer can only be one of these three things. All the best, Matt please email support@easycomposites.co.uk with us your company/order details; I'm struggling to find you on our system. Thanks.
Matt StathamEasy Composites / Carbon Mods - Technical Sales
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