Quick question regarding CS25 Silicone rubber

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Quick question regarding CS25 Silicone rubber

Quick question regarding CS25 Silicone rubber

Author	Message
TURK	TURK posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 101, Visits: 662	+x Matthieu Libeert - 1/18/2019 4:58:08 PM Great to hear you like my tutorials, I have a couple of silicone tutorials coming in the next two weeks. I use AC silicone and the CC silicone. Did a pour of 5kg for the tutorials but still use the two cup system. As much as I've tried mixing everything in one cup I still have uncured silicone. on the bottom or sides. You could check when you remove the left overs from the cup and feel the bottom of the leftovers if it is still sticky or not Thanks for the information Matthieu, looking forward to your next silicone tutorials mate. Removing the 'cured' silicone from the buckets after the pour ( the following day ), didn't show any signs of tackyness. So it was well cured. The overall colour of the mixed silicone looked to be uniform, no streaks, so my estimation would be that it was mixed sufficiently. But as you have mentioned, and Hanaldo, there may be a mixing issue ....................... even though it may not be apparent, it's quite possible when mixing large quantities of silicone. In future, I will use the two cup pour method as per your recommendation "Certainly no harm will come to the moulds by wiping down with warm soapy water so you try that to see if it is a residue from the VacCast pour." I haven't cast the 'Vac-Cast Epoxy Resin' yet Warren, it's the result of the silicone moulds sitting idle for a week. TURK T4 Concepts
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Hanaldo	Hanaldo posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	It is definitely a mixing issue - have seen it with some of our condensation cure silicones when they are mixed off ratio, the oils from the unreacted components leach out. Be a bit careful, on the odd occasion the moulds with this problem will stick. Use your Mann Ease Release before casting into the mould. Edited 6 Years Ago by Hanaldo
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Warren (Staff)	Warren (Staff) posted 6 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	Hi Turk, Looking at the pictures, it is hard to tell what is going on in that sense. I have not heard of the silicone "sweating" or leeching an oily substance unless there are some mixing issues going on. Normally I would expect a casting resin to sweat slightly into a mould if there is moisture present or a very slight mix ratio imbalance. (the exotherm heat can drive the excess component to the resin surface ). Certainly no harm will come to the moulds by wiping down with warm soapy water so you try that to see if it is a residue from the VacCast pour. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Matthieu Libeert	Matthieu Libeert posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	+x TURK - 1/18/2019 7:57:33 AM Hi Matthieu, and thanks for taking the time to respond I remember subscribing to your excellent YouTube channel last year mate, in fact, I went back and had a look at one of your YouTube 'buttons' where you used a silicone rubber. I think you used the 'Addition' cure silicone, so I don't think you would encounter the same problems as I have with my 'Condensation' cure silicone. I'm way past mixing simple 'cups' of silicone here! ................ I'm having to use 10 litre buckets for mixing and degassing. So the 2 pour technique is dispensed with here, as I'm having to mix and pour 4kilo's at a time! I just make sure that I thoroughly mix the contents. Good tip about the first cast as a test cast using the Xencast P4 resin. But the moulds are rather big ( 2 of them ), hopefully that won't be necessary if I can clean both these silicone moulds. I may have to email Warren today as he may not of seen this post. Thanks for your support mate. TURK T4 Concepts Great to hear you like my tutorials, I have a couple of silicone tutorials coming in the next two weeks. I use AC silicone and the CC silicone. Did a pour of 5kg for the tutorials but still use the two cup system. As much as I've tried mixing everything in one cup I still have uncured silicone. on the bottom or sides. You could check when you remove the left overs from the cup and feel the bottom of the leftovers if it is still sticky or not Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
	Reply Like 2
TURK	TURK posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 101, Visits: 662	Hi Matthieu, and thanks for taking the time to respond I remember subscribing to your excellent YouTube channel last year mate, in fact, I went back and had a look at one of your YouTube 'buttons' where you used a silicone rubber. I think you used the 'Addition' cure silicone, so I don't think you would encounter the same problems as I have with my 'Condensation' cure silicone. I'm way past mixing simple 'cups' of silicone here! ................ I'm having to use 10 litre buckets for mixing and degassing. So the 2 pour technique is dispensed with here, as I'm having to mix and pour 4kilo's at a time! I just make sure that I thoroughly mix the contents. Good tip about the first cast as a test cast using the Xencast P4 resin. But the moulds are rather big ( 2 of them ), hopefully that won't be necessary if I can clean both these silicone moulds. I may have to email Warren today as he may not of seen this post. Thanks for your support mate. TURK T4 Concepts
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Matthieu Libeert	Matthieu Libeert posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	+x TURK - 1/17/2019 4:08:47 PM Mmmmmmmmmmmmmmm ...................... anybody? Surely someone else must be using CS25! Is that 'oily' residue a regular thing now? I used CS25 a couple of years ago, and that oily residue didn't appear. Why is that silicone doing this, last 2 attempts has seen a build-up of that oily residue. TURK T4 Concepts Never had any problems like that on my moulds UNLESS I didn't use the 2 cup system; first mixing in one cup, then pouring over in a second cup to mix again to make sure everything is well mixed. Sounds like your silicone is sweating... I'm not 100% sure but warm soapy water shouldn't cause to much problems, maybe wait for Warren to confirm this... Just make sure that before use you put your mould in the oven to make sure no moist is left. What I also like to do to clean moulds is use a clean cloth and some easylease... Best case you'll remove some excess residue, worst case you'll add some more release. So It's a win win sitaution... As an extra tip: I always do a first pour with xencast P4 which is relatively cheap and fast curing... that way while demoulding you'll remove any residue or dust that was still on you mould after demoulding it from the plug. I see it's a big mould but you could do a small pour just on the bottom where you have some residue like you say, or pour it in 4 times so you have all the sides Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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TURK	TURK posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 101, Visits: 662	Mmmmmmmmmmmmmmm ...................... anybody? Surely someone else must be using CS25! Is that 'oily' residue a regular thing now? I used CS25 a couple of years ago, and that oily residue didn't appear. Why is that silicone doing this, last 2 attempts has seen a build-up of that oily residue. TURK T4 Concepts
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TURK	TURK posted 6 Years Ago HOT Topic Details
Group: Forum Members Posts: 101, Visits: 662	Hi guys, I've finally managed to mould two ( Offside & Nearside ) headlight cover moulds using EC CS25 Silicone rubber. The quality and definition of the finish is superb! While I've been busy working on the next stage of the procedure .................. casting 'Vac-Cast Epoxy Resin' into the silicone moulds, a week has elapsed. Now my silicone moulds have built-up an oily residue inside them!? >> My question is ............. can I simply 'wash out' with just a damp cloth the oily residue? Or should I be cleaning the residue off with EC Mould Cleaner? Other option I've read about are - Soapy water Or even, talcing powder!? And, how will this effect my Vac-Cast Epoxy Cast? Any opinions ( comments ) greatly received. Many thanks TURK T4 Concepts
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