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MarkMK
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I know from reading earlier posts that you've spent a lot of time getting the cure schedule right to get such excellent results. The question is, are you willing to share your knowledge, or does the datasheet associated with the SHD product provide all that's required?
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scottracing
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now that is some quality looking parts, and exactly what you should be able to achieve with prepregs, I still havent got round to using my labovens in anger due to the new baby but I will certainly give SHD a call when I need some material. Do they have a minimum order qty?
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morepower
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MarkMK (15/10/2015)
I know from reading earlier posts that you've spent a lot of time getting the cure schedule right to get such excellent results. The question is, are you willing to share your knowledge, or does the datasheet associated with the SHD product provide all that's required? The pdf will give you enough info to get started. I would suggest you log the cure schedule you run and fine tune it from there. Using a ramp and dwell controller would be really helpful too.
They will do smaller quantities. Not sure if they have a minimum as I now order at least 20 meters usually 25 meters as some of my work is not material heavy but is time consuming so I get enough to make sure I do not have issues with outlife.
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20_rc51_00
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Here are a few recommendations from various sources as to lay up schedule etc.. all which I pulled from the net with a bit of digging. The cytec doc talks about edge bleeding and top bleeding for debulk and for sure if I recall correctly. Might want to try each/both. One or the other may drain too much resin or not enough. If the SHD TDS had this info it would be what you're after etc. Nothing says that you can't actually come up with a better way too. Also I would suggest stretch out the dwell time so that the resin is at it's thinnest for quite a while. This can allow air to be pulled off, but may be what leads to too much resin pulled off too with one method or the other. Also, report back with your results ! 
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morepower
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20_rc51_00 (16/10/2015)
Here are a few recommendations from various sources as to lay up schedule etc.. all which I pulled from the net with a bit of digging. The cytec doc talks about edge bleeding and top bleeding for debulk and for sure if I recall correctly. Might want to try each/both. One or the other may drain too much resin or not enough. If the SHD TDS had this info it would be what you're after etc. Nothing says that you can't actually come up with a better way too. Also I would suggest stretch out the dwell time so that the resin is at it's thinnest for quite a while. This can allow air to be pulled off, but may be what leads to too much resin pulled off too with one method or the other. Also, report back with your results ! The problem with using other recommendations from other suppliers is you are up against different chemistry. Some will work or help others will make it worse.. I spent 6 months with one material getting different results from small changes and it has been a mixture of breather stack and ramp and dwell that I spent all my time on. Oddly some moulds need peel ply on the flange to bleed air and some don't. After a while you get to know which ones do and which ones don't. But the cure schedule never changes. You just need to make sure the oven is accurate with even temp top, bottom and middle or find a way to make sure you have the parts where the oven is working best. You may have to fine tune the controller and compensate for any differences. Mine is 2 degrees different from the thermocouple location to the centre of the oven. Dwell times are important but I have found controlling ramp is actually more important than you think. Moulds may have different thickness so getting the moulds to all heat up within a margin that keeps them quite close will make all your parts cure consistently.
Its a bit of work to get your oven to be consistent but it is worth it... The SHD cure schedule is based on my findings and although I have not given them my breather stack info it is not to hide anything it is simply due to different moulds work differently so the only thing that will not change is the cure cycle.
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sam
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If it's some help try a major company named PPG paints they have branches in Australia and other parts of the world. I have used their product before - that may fit the bill, speak with there technical section and they have a head office in UK somewhere. All the best
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sam
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If it's some help try a major company named PPG paints they have branches in Australia and other parts of the world. I have used their product before, that may fit the bill, speak with there technical section and they have a head office in UK somewhere. as well as Australia. All the best
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MarkMK
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Having had a look at the SHD PDF, it certainly does look like it offers the opportunity for some short cure cycles, down to 3 hours for temperatures within the range of the Unimould tooling system
morepower - Is DF212 just the surface layer fabric and does it need to be backed up with another of their products, or does it come in various weights? Also, how does it stack up in terms of price when compared with EC's OOA fabric?
Realistically, will it also take fair bit of experimentation in order to achieve perfect surface finish results using this, assuming that the user has an oven with stable temperature control and the ability to ramp appropriately
Certainly looks appealing, but would just like to fully understand any 'cons' to trying it, as opposed to EC's material and I'm sure that you're well placed to make a realistic assessment of that
Cheers
Mark
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morepower
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Mark. To be honest ignore the fact you CAN get a 3 hour cure. Too many seem to want to cure hot and fast. It does not allow the resin to flow and get the surface you want. They have other backing materials they can suggest to go with the DF212... But there will be another new material which will have various weights, better clarity but will need to be cured at a slightly higher temperature. But I will say even the DF 212 has better clarity than the VTF261 (Easy Preg surface). It would take minimal experimenting to be honest as the cure cycle on the PDF is very close as I gave them that info. It is more about having an accurate and consistent oven. The breather stack is where you may need to do some fine tuning but that varies from mould to mould. Price? I know what price I pay but I will say it is quite a big saving over EC's material. Pro's. Better clarity Better surface (EC's material was the one others tried to emulate as it was very good and could be perfect but I have used both (About 100 meters of VTF261) and have had better more consistent results with the DF212. I would say the EC material is about 95% there compared to 60 to 70% of most of the others but the DF212 is 99%. Price Con's You may need to spend a little time adjusting to using it and finding a way to get the best results. (same for any material you are not used too) This is straight out of the mould. No lacquer or polish it was just pulled out and I took a photo...  
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MarkMK
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Thanks for the comprehensive reply morepower, it certainly seems like it's worth trying out with so many potential advantages
Mark
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