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David Grant
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+x+x+xPVA would be a super safe option if applied evenly. However it will likely leave surface marring that needs polishing out. Alternatively 5 or 6 coats of mould release wax should have no issues but leave a better finish. What was happening? did the solvents attack/etch the surface? The tube became dirty inside the bore (my bad) and I used Easy-Lease Mould Cleaner, things didn't look right after that. Once I used the Easy-Lease Chemical Release Agent the tube became brittle and cracks started forming, only had to tap it and it shattered. Tube on back order so project on hold at mo. Whilst I'm here Warren, I did a pigment test to the exact dimensions of the final cast (width/depth but only 75mm long) and added one drop of the CULR Epoxy Pigment White to 25g of epoxy, so less than stated. The test came out great and the led light will pass through - however even with the lights on full brightness it only passes through three quarters of the length of the test piece. So I will have to go for a clear cast when I was trying to achieve a frosted look. I can't take a photo to demonstrate as I've already cut the cable on leds but hope this makes sense. Warren, would just like to clarify the release wax option, it says (Suitable Uses) that it is not suitable for high temperature applications such as elevated temperature cure, pre-preg or wet-lay where exotherm in the part is likely to take the mould surface over 50°C. On my first post you said "The above advice with the fan may help keep the exotherm down a bit. Typically I would expect to see around 60C during the cure - more if the exotherm begins to run away a bit." So can I still use the wax or should I go for the PVA? Sorry need to add more as wish to get order in asap - looking at other suppliers they are saying... " Stoner Miracle Gloss M-08 Maximum Mold Release Wax was the GRP industries first paste release wax and is still the most widely used, due to it's excellent performance. Can withstand exotherm of up to 120 C."
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David Grant
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Group: Forum Members
Posts: 13,
Visits: 86
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+x+xPVA would be a super safe option if applied evenly. However it will likely leave surface marring that needs polishing out. Alternatively 5 or 6 coats of mould release wax should have no issues but leave a better finish. What was happening? did the solvents attack/etch the surface? The tube became dirty inside the bore (my bad) and I used Easy-Lease Mould Cleaner, things didn't look right after that. Once I used the Easy-Lease Chemical Release Agent the tube became brittle and cracks started forming, only had to tap it and it shattered. Tube on back order so project on hold at mo. Whilst I'm here Warren, I did a pigment test to the exact dimensions of the final cast (width/depth but only 75mm long) and added one drop of the CULR Epoxy Pigment White to 25g of epoxy, so less than stated. The test came out great and the led light will pass through - however even with the lights on full brightness it only passes through three quarters of the length of the test piece. So I will have to go for a clear cast when I was trying to achieve a frosted look. I can't take a photo to demonstrate as I've already cut the cable on leds but hope this makes sense. Warren, would just like to clarify the release wax option, it says (Suitable Uses) that it is not suitable for high temperature applications such as elevated temperature cure, pre-preg or wet-lay where exotherm in the part is likely to take the mould surface over 50°C. On my first post you said "The above advice with the fan may help keep the exotherm down a bit. Typically I would expect to see around 60C during the cure - more if the exotherm begins to run away a bit." So can I still use the wax or should I go for the PVA?
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David Grant
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Group: Forum Members
Posts: 13,
Visits: 86
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+xPVA would be a super safe option if applied evenly. However it will likely leave surface marring that needs polishing out. Alternatively 5 or 6 coats of mould release wax should have no issues but leave a better finish. What was happening? did the solvents attack/etch the surface? The tube became dirty inside the bore (my bad) and I used Easy-Lease Mould Cleaner, things didn't look right after that. Once I used the Easy-Lease Chemical Release Agent the tube became brittle and cracks started forming, only had to tap it and it shattered. Tube on back order so project on hold at mo. Whilst I'm here Warren, I did a pigment test to the exact dimensions of the final cast (width/depth but only 75mm long) and added one drop of the CULR Epoxy Pigment White to 25g of epoxy, so less than stated. The test came out great and the led light will pass through - however even with the lights on full brightness it only passes through three quarters of the length of the test piece. So I will have to go for a clear cast when I was trying to achieve a frosted look. I can't take a photo to demonstrate as I've already cut the cable on leds but hope this makes sense.
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Warren (Staff)
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Group: Administrators
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PVA would be a super safe option if applied evenly. However it will likely leave surface marring that needs polishing out. Alternatively 5 or 6 coats of mould release wax should have no issues but leave a better finish.
What was happening? did the solvents attack/etch the surface?
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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David Grant
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Group: Forum Members
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Visits: 86
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Had a major problem with the clear acrylic/perspex tube whilst prepping. Not sure if it was the Easy-Lease Chemical Release Agent that reacted with the acrylic/perspex. However I have disposed of the tube and now having to order new length. Looking at the other release agents, would it be better to use the PVA Mould Release Agent to line the inner tube for casting. Some help would be appreciated please.
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Warren (Staff)
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Group: Administrators
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As you might experience a bit of flex etc during use, I would look at the ET515 Semi Flexible 15min Professional Epoxy Adhesive as it has a high flexural strength when under shock and vibration.
Warren PenalverEasy Composites / Carbon Mods - Technical Support Assistant
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David Grant
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Group: Forum Members
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Ok got all that thanks. Once cast and set I will need to bond the upright to the base and put the beech top on the upright - see photo of top part (30mm round) Been looking at your Structural Adhesives and wonder if this work and if so which one. 
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Warren (Staff)
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Group: Administrators
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It would be difficult but if the end is firming up then the rest should be similar. You could also leave a small amount in a mixing cup around the same thickness and use that as a guide. You are looking around 12 hours or more.
With the pigment, mix the pigment into the resin in one large batch. Then decant from the resin batch as required adding the hardener needed with each batch. Keep a lid on the resin batch and give it a stir before each decanting to ensure the pigment doesn't settle out.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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David Grant
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Group: Forum Members
Posts: 13,
Visits: 86
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+x2 pours will be safer but you should be able to do it in one with the relatively small volume. It is always a bit hard to tell in these situations as wood can insulate the cast a lot and cause an exotherm. Perhaps setting up a fan to blow over the resin filled tube once poured might help take some of the heat away. Yes we would recommend sealing wood in almost all cases. Resin can soak in displacing air which can then get trapped as bubbles in your resin. Use EasyLease or similar release agent on the tube. At that length you will struggle to pull it off so you may need to very carefully slit the tube to "peel" it off the casting. I would do a small experiment first to see how much pigment you need for the desired look. The above advice with the fan may help keep the exotherm down a bit. Typically I would expect to see around 60C during the cure - more if the exotherm begins to run away a bit. Warren, A great help you've been. Regarding two pours, would that be possible as I couldn't check the ‘B-stage’ down the tube. If I've calculated correctly then I should need about 540g of resin. Happy to test pigment for desired look but would you advice I keep log of ratio of pigment drops to resin so I can match on main pour. Dave
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Warren (Staff)
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Group: Administrators
Posts: 2.5K,
Visits: 8.5K
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2 pours will be safer but you should be able to do it in one with the relatively small volume. It is always a bit hard to tell in these situations as wood can insulate the cast a lot and cause an exotherm. Perhaps setting up a fan to blow over the resin filled tube once poured might help take some of the heat away.
Yes we would recommend sealing wood in almost all cases. Resin can soak in displacing air which can then get trapped as bubbles in your resin.
Use EasyLease or similar release agent on the tube. At that length you will struggle to pull it off so you may need to very carefully slit the tube to "peel" it off the casting.
I would do a small experiment first to see how much pigment you need for the desired look.
The above advice with the fan may help keep the exotherm down a bit. Typically I would expect to see around 60C during the cure - more if the exotherm begins to run away a bit.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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