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Pkzipper
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Group: Forum Members
Posts: 7,
Visits: 21
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+x+x+x+xHi. Don’t know if it’s relevant but I am currently doing an envelope bagging of the lock cover plate for my kit car ( waiting for the base coat to go tacky as I type this). The fixingings on this are just holes that a screw and cover go into. I’ve taped bits of stirring stick onto the back and filled the hole with mould wax so there should be no leakage and should be easy to remove from the back later. Hi, We've not been online over the weekend but basically Hanaldo has stated what would be the EC opinion anyway. It sounds like you're aware of the choices you have (in removing the texture from your original parts) which are to: 1. Sacrifice the original (by filling and smoothing out the texture).
This is quickest and most accurate (least distortion). Disadvantage of course is that it sacrifices the original. 2. Do a very thick gelcoat on the mould and then smooth out the texture in the mould.
This can offer a decent compromise allowing you to not sacrifice the original but to reduce the workload and cost and reduce the risk of distortion however flatting and polishing 'in the negative' is much more difficult, it's hard to see when you've got it right and you're often flatting on the inside of a concave plain which is much more difficult. Also, although you reduce the risk of distortion from going back and forth between part and mould you will introduce some inaccuracy by necessarily flatting down to the lowest point in the texture rather than being able to build up to the highest point or striking a mid point (as you would with options 1 or 3. 3. Take a quick (splash) mould off the original and then make a GRP copy of the original (a splash part) which you can modify, including taking any texture out.
This gives you the most scope for 'correction' and avoids sacrificing the original. Disadvantages are that it's the most work, the most cost (in materials) and can introduce distortion because you're turning the whole process through twice by the time you get to the finished part. Moulding can be a bit like 'Chinese Whispers' and some distortion can creep in if you're not careful. There's pros and cons to all approaches; choosing the right one is subjective and depends on your priorities. Hello and thank you Matt, Option one is the one I need to be prepared for as some of the original components have high value. I am left with the choice of two and three. I appreciate you cannot pass on definitive direction as there is not one right way nor do you want the blow back if it fails. I am leaning towards option three as from what I am hearing sanding a positive is way easier than sanding a negative mold. Also, sanding and polishing pattern coat primer and high gloss is way easier than gel coat! Its just the flex and distortion issue. A well made mold should eliminate the possibility of distorting the part but the finish would be suspect. The splash mold is my concern and I know it is my choice but I am just looking for reference. Splash mold's, as supposed to permanent molds, make a quick replica of the original but that original could be effect if the mold is too flimsy but how do you gauge that? Or do you build a stronger mold from glass to be safe but at what cost? What about cost effective backing media like Plaster or something that is cheap and rigid? I would think it might be better in the case of making a working replica to focus on strengthening it for it not to warp while its being worked but with what? Plaster is heavy but does not expand. Silicone is too flimsy and expanding foam well is expanding and could/would it distort the form while expanding. Am I over thinkin this?? Finally can you chime in on the issue of the posts, clips and attachment points on the back? Thank you again P.S Where are all the PDF from the resource section? I only see the videos. I want to look at the PDF that had reference to using honeycomb. >> Am I over thinkin this?? Yes, definitely! Forget using weird and wonderful alternatives to GRP; plasters, silicones - they're not the way to do this. It sounds like you just need some experience with GRP; conventional polyester gelcoat, chopped strand matt and polyester resin layup. Distortion is caused by shrinkage, a good laminator knows to take their time, building up layers one at a time over a period of a few days, this will eliminate most shrinkage issues. The thickness of the splash moulds and splash parts will tend to determine themselves; you just need them to be stable and secure without using unnecessary material making either of them too sturdy. Start simple, take a splash mould, satisfy yourself up to that stage. Then make the splash part (with a thick gel so you can modify the texture) and then make your final mould. You'll be a dab-hand by then. Use Uni-Mould when you make the final mould; it will be much thicker and will need a vinylester gelcoat so Uni-Mould is definitely the way to go. >> P.S Where are all the PDF from the resource section? At the moment we just have the videos. We did have some PDFs (not related to honeycomb) but we're gradually updating a lot of this content. I'm afraid we don't currently have any tutorials or guides that relates to working with honeycomb although this is something that we plan to do fairly soon. >> Finally can you chime in on the issue of the posts, clips and attachment points on the back? Did you attach the image, I can't see it? There have been lots of discussions about mounting clips, I'm not 100% sure what your particular requirement is but if you can't find your answer already then please let me know some more about what you're trying to do. Thank you Matt for the more direct response. I think I am settled with the slash mold and going slower as opposed too trying to do a mold quickly. As for the clips, in my first post i left a link to a post with a few pictures of what we mean. ( http://www.talkcomposites.com/23154/CF-clips-for-car-dashboard ). What is the BEST way to make and attach the clips? Thank you again.
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Matt (Staff)
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Group: Forum Members
Posts: 680,
Visits: 1.9K
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+x+x+x+x+xHi. Don’t know if it’s relevant but I am currently doing an envelope bagging of the lock cover plate for my kit car ( waiting for the base coat to go tacky as I type this). The fixingings on this are just holes that a screw and cover go into. I’ve taped bits of stirring stick onto the back and filled the hole with mould wax so there should be no leakage and should be easy to remove from the back later. Hi, We've not been online over the weekend but basically Hanaldo has stated what would be the EC opinion anyway. It sounds like you're aware of the choices you have (in removing the texture from your original parts) which are to: 1. Sacrifice the original (by filling and smoothing out the texture).
This is quickest and most accurate (least distortion). Disadvantage of course is that it sacrifices the original. 2. Do a very thick gelcoat on the mould and then smooth out the texture in the mould.
This can offer a decent compromise allowing you to not sacrifice the original but to reduce the workload and cost and reduce the risk of distortion however flatting and polishing 'in the negative' is much more difficult, it's hard to see when you've got it right and you're often flatting on the inside of a concave plain which is much more difficult. Also, although you reduce the risk of distortion from going back and forth between part and mould you will introduce some inaccuracy by necessarily flatting down to the lowest point in the texture rather than being able to build up to the highest point or striking a mid point (as you would with options 1 or 3. 3. Take a quick (splash) mould off the original and then make a GRP copy of the original (a splash part) which you can modify, including taking any texture out.
This gives you the most scope for 'correction' and avoids sacrificing the original. Disadvantages are that it's the most work, the most cost (in materials) and can introduce distortion because you're turning the whole process through twice by the time you get to the finished part. Moulding can be a bit like 'Chinese Whispers' and some distortion can creep in if you're not careful. There's pros and cons to all approaches; choosing the right one is subjective and depends on your priorities. Hello and thank you Matt, Option one is the one I need to be prepared for as some of the original components have high value. I am left with the choice of two and three. I appreciate you cannot pass on definitive direction as there is not one right way nor do you want the blow back if it fails. I am leaning towards option three as from what I am hearing sanding a positive is way easier than sanding a negative mold. Also, sanding and polishing pattern coat primer and high gloss is way easier than gel coat! Its just the flex and distortion issue. A well made mold should eliminate the possibility of distorting the part but the finish would be suspect. The splash mold is my concern and I know it is my choice but I am just looking for reference. Splash mold's, as supposed to permanent molds, make a quick replica of the original but that original could be effect if the mold is too flimsy but how do you gauge that? Or do you build a stronger mold from glass to be safe but at what cost? What about cost effective backing media like Plaster or something that is cheap and rigid? I would think it might be better in the case of making a working replica to focus on strengthening it for it not to warp while its being worked but with what? Plaster is heavy but does not expand. Silicone is too flimsy and expanding foam well is expanding and could/would it distort the form while expanding. Am I over thinkin this?? Finally can you chime in on the issue of the posts, clips and attachment points on the back? Thank you again P.S Where are all the PDF from the resource section? I only see the videos. I want to look at the PDF that had reference to using honeycomb. >> Am I over thinkin this?? Yes, definitely! Forget using weird and wonderful alternatives to GRP; plasters, silicones - they're not the way to do this. It sounds like you just need some experience with GRP; conventional polyester gelcoat, chopped strand matt and polyester resin layup. Distortion is caused by shrinkage, a good laminator knows to take their time, building up layers one at a time over a period of a few days, this will eliminate most shrinkage issues. The thickness of the splash moulds and splash parts will tend to determine themselves; you just need them to be stable and secure without using unnecessary material making either of them too sturdy. Start simple, take a splash mould, satisfy yourself up to that stage. Then make the splash part (with a thick gel so you can modify the texture) and then make your final mould. You'll be a dab-hand by then. Use Uni-Mould when you make the final mould; it will be much thicker and will need a vinylester gelcoat so Uni-Mould is definitely the way to go. >> P.S Where are all the PDF from the resource section? At the moment we just have the videos. We did have some PDFs (not related to honeycomb) but we're gradually updating a lot of this content. I'm afraid we don't currently have any tutorials or guides that relates to working with honeycomb although this is something that we plan to do fairly soon. >> Finally can you chime in on the issue of the posts, clips and attachment points on the back? Did you attach the image, I can't see it? There have been lots of discussions about mounting clips, I'm not 100% sure what your particular requirement is but if you can't find your answer already then please let me know some more about what you're trying to do. Thank you Matt for the more direct response. I think I am settled with the slash mold and going slower as opposed too trying to do a mold quickly. As for the clips, in my first post i left a link to a post with a few pictures of what we mean. ( http://www.talkcomposites.com/23154/CF-clips-for-car-dashboard ). What is the BEST way to make and attach the clips? Thank you again. This is a difficult one to answer because there isn't one right way and you generally need to adapt depending on what is available. In our experience (from when we started off life manufacturing carbon fibre car parts) we would look closely at a clip and work out not how to copy it exactly but how to copy what it needs to do. Often this would mean replacing the complex moulded clip with a simply metal bracket or fastener that does the same job. Generally the moulded plastic clips look the way they do because they're designed to be injection moulded right from the start. Trying to recreate an injection moulding in a moulded composite part can be extremely complicated and is usually unnecessary - you'll often find that a folded aluminium bracket bonded onto the inside of your part will work just as well. I did notice that early in this thread someone posted some links to clips on Alibab0/Google; actually, following this link there were some interesting clips and brackets listed that might give you some inspiration. Another possibility would be to take moulds off the original parts using RTV silicone rubber and then cast them in polyurethane.We have a toughened high strength polyurethane which is suitable for this type of work called Xencast P6. These could be moulded to have a larger bond area (like a flat flange at the bottom) and then bonded to the inside of your parts using a tough adhesive such as VuduGlu VM100.
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Pkzipper
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Group: Forum Members
Posts: 7,
Visits: 21
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+x+x+x+x+x+xHi. Don’t know if it’s relevant but I am currently doing an envelope bagging of the lock cover plate for my kit car ( waiting for the base coat to go tacky as I type this). The fixingings on this are just holes that a screw and cover go into. I’ve taped bits of stirring stick onto the back and filled the hole with mould wax so there should be no leakage and should be easy to remove from the back later. Hi, We've not been online over the weekend but basically Hanaldo has stated what would be the EC opinion anyway. It sounds like you're aware of the choices you have (in removing the texture from your original parts) which are to: 1. Sacrifice the original (by filling and smoothing out the texture).
This is quickest and most accurate (least distortion). Disadvantage of course is that it sacrifices the original. 2. Do a very thick gelcoat on the mould and then smooth out the texture in the mould.
This can offer a decent compromise allowing you to not sacrifice the original but to reduce the workload and cost and reduce the risk of distortion however flatting and polishing 'in the negative' is much more difficult, it's hard to see when you've got it right and you're often flatting on the inside of a concave plain which is much more difficult. Also, although you reduce the risk of distortion from going back and forth between part and mould you will introduce some inaccuracy by necessarily flatting down to the lowest point in the texture rather than being able to build up to the highest point or striking a mid point (as you would with options 1 or 3. 3. Take a quick (splash) mould off the original and then make a GRP copy of the original (a splash part) which you can modify, including taking any texture out.
This gives you the most scope for 'correction' and avoids sacrificing the original. Disadvantages are that it's the most work, the most cost (in materials) and can introduce distortion because you're turning the whole process through twice by the time you get to the finished part. Moulding can be a bit like 'Chinese Whispers' and some distortion can creep in if you're not careful. There's pros and cons to all approaches; choosing the right one is subjective and depends on your priorities. Hello and thank you Matt, Option one is the one I need to be prepared for as some of the original components have high value. I am left with the choice of two and three. I appreciate you cannot pass on definitive direction as there is not one right way nor do you want the blow back if it fails. I am leaning towards option three as from what I am hearing sanding a positive is way easier than sanding a negative mold. Also, sanding and polishing pattern coat primer and high gloss is way easier than gel coat! Its just the flex and distortion issue. A well made mold should eliminate the possibility of distorting the part but the finish would be suspect. The splash mold is my concern and I know it is my choice but I am just looking for reference. Splash mold's, as supposed to permanent molds, make a quick replica of the original but that original could be effect if the mold is too flimsy but how do you gauge that? Or do you build a stronger mold from glass to be safe but at what cost? What about cost effective backing media like Plaster or something that is cheap and rigid? I would think it might be better in the case of making a working replica to focus on strengthening it for it not to warp while its being worked but with what? Plaster is heavy but does not expand. Silicone is too flimsy and expanding foam well is expanding and could/would it distort the form while expanding. Am I over thinkin this?? Finally can you chime in on the issue of the posts, clips and attachment points on the back? Thank you again P.S Where are all the PDF from the resource section? I only see the videos. I want to look at the PDF that had reference to using honeycomb. >> Am I over thinkin this?? Yes, definitely! Forget using weird and wonderful alternatives to GRP; plasters, silicones - they're not the way to do this. It sounds like you just need some experience with GRP; conventional polyester gelcoat, chopped strand matt and polyester resin layup. Distortion is caused by shrinkage, a good laminator knows to take their time, building up layers one at a time over a period of a few days, this will eliminate most shrinkage issues. The thickness of the splash moulds and splash parts will tend to determine themselves; you just need them to be stable and secure without using unnecessary material making either of them too sturdy. Start simple, take a splash mould, satisfy yourself up to that stage. Then make the splash part (with a thick gel so you can modify the texture) and then make your final mould. You'll be a dab-hand by then. Use Uni-Mould when you make the final mould; it will be much thicker and will need a vinylester gelcoat so Uni-Mould is definitely the way to go. >> P.S Where are all the PDF from the resource section? At the moment we just have the videos. We did have some PDFs (not related to honeycomb) but we're gradually updating a lot of this content. I'm afraid we don't currently have any tutorials or guides that relates to working with honeycomb although this is something that we plan to do fairly soon. >> Finally can you chime in on the issue of the posts, clips and attachment points on the back? Did you attach the image, I can't see it? There have been lots of discussions about mounting clips, I'm not 100% sure what your particular requirement is but if you can't find your answer already then please let me know some more about what you're trying to do. Thank you Matt for the more direct response. I think I am settled with the slash mold and going slower as opposed too trying to do a mold quickly. As for the clips, in my first post i left a link to a post with a few pictures of what we mean. ( http://www.talkcomposites.com/23154/CF-clips-for-car-dashboard ). What is the BEST way to make and attach the clips? Thank you again. This is a difficult one to answer because there isn't one right way and you generally need to adapt depending on what is available. In our experience (from when we started off life manufacturing carbon fibre car parts) we would look closely at a clip and work out not how to copy it exactly but how to copy what it needs to do. Often this would mean replacing the complex moulded clip with a simply metal bracket or fastener that does the same job. Generally the moulded plastic clips look the way they do because they're designed to be injection moulded right from the start. Trying to recreate an injection moulding in a moulded composite part can be extremely complicated and is usually unnecessary - you'll often find that a folded aluminium bracket bonded onto the inside of your part will work just as well. I did notice that early in this thread someone posted some links to clips on Alibab0/Google; actually, following this link there were some interesting clips and brackets listed that might give you some inspiration. Another possibility would be to take moulds off the original parts using RTV silicone rubber and then cast them in polyurethane.We have a toughened high strength polyurethane which is suitable for this type of work called Xencast P6. These could be moulded to have a larger bond area (like a flat flange at the bottom) and then bonded to the inside of your parts using a tough adhesive such as VuduGlu VM100. Thank you again for the reply, I guess my biggest question/concern would be the strength of a glued/bonded clip post curing. Obviously fused would be the strongest but is the right bonding process just as strong? We have all seen and probably tried to repair and glue back a broken clip and thought the repair would be permanent to find that it was mostly temporary and un-reliable so I am wanting to avoid the temporary unreliable bond on a costly CF replica or part!
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Matt (Staff)
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Group: Forum Members
Posts: 680,
Visits: 1.9K
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+x+x+x+x+x+x+xHi. Don’t know if it’s relevant but I am currently doing an envelope bagging of the lock cover plate for my kit car ( waiting for the base coat to go tacky as I type this). The fixingings on this are just holes that a screw and cover go into. I’ve taped bits of stirring stick onto the back and filled the hole with mould wax so there should be no leakage and should be easy to remove from the back later. Hi, We've not been online over the weekend but basically Hanaldo has stated what would be the EC opinion anyway. It sounds like you're aware of the choices you have (in removing the texture from your original parts) which are to: 1. Sacrifice the original (by filling and smoothing out the texture).
This is quickest and most accurate (least distortion). Disadvantage of course is that it sacrifices the original. 2. Do a very thick gelcoat on the mould and then smooth out the texture in the mould.
This can offer a decent compromise allowing you to not sacrifice the original but to reduce the workload and cost and reduce the risk of distortion however flatting and polishing 'in the negative' is much more difficult, it's hard to see when you've got it right and you're often flatting on the inside of a concave plain which is much more difficult. Also, although you reduce the risk of distortion from going back and forth between part and mould you will introduce some inaccuracy by necessarily flatting down to the lowest point in the texture rather than being able to build up to the highest point or striking a mid point (as you would with options 1 or 3. 3. Take a quick (splash) mould off the original and then make a GRP copy of the original (a splash part) which you can modify, including taking any texture out.
This gives you the most scope for 'correction' and avoids sacrificing the original. Disadvantages are that it's the most work, the most cost (in materials) and can introduce distortion because you're turning the whole process through twice by the time you get to the finished part. Moulding can be a bit like 'Chinese Whispers' and some distortion can creep in if you're not careful. There's pros and cons to all approaches; choosing the right one is subjective and depends on your priorities. Hello and thank you Matt, Option one is the one I need to be prepared for as some of the original components have high value. I am left with the choice of two and three. I appreciate you cannot pass on definitive direction as there is not one right way nor do you want the blow back if it fails. I am leaning towards option three as from what I am hearing sanding a positive is way easier than sanding a negative mold. Also, sanding and polishing pattern coat primer and high gloss is way easier than gel coat! Its just the flex and distortion issue. A well made mold should eliminate the possibility of distorting the part but the finish would be suspect. The splash mold is my concern and I know it is my choice but I am just looking for reference. Splash mold's, as supposed to permanent molds, make a quick replica of the original but that original could be effect if the mold is too flimsy but how do you gauge that? Or do you build a stronger mold from glass to be safe but at what cost? What about cost effective backing media like Plaster or something that is cheap and rigid? I would think it might be better in the case of making a working replica to focus on strengthening it for it not to warp while its being worked but with what? Plaster is heavy but does not expand. Silicone is too flimsy and expanding foam well is expanding and could/would it distort the form while expanding. Am I over thinkin this?? Finally can you chime in on the issue of the posts, clips and attachment points on the back? Thank you again P.S Where are all the PDF from the resource section? I only see the videos. I want to look at the PDF that had reference to using honeycomb. >> Am I over thinkin this?? Yes, definitely! Forget using weird and wonderful alternatives to GRP; plasters, silicones - they're not the way to do this. It sounds like you just need some experience with GRP; conventional polyester gelcoat, chopped strand matt and polyester resin layup. Distortion is caused by shrinkage, a good laminator knows to take their time, building up layers one at a time over a period of a few days, this will eliminate most shrinkage issues. The thickness of the splash moulds and splash parts will tend to determine themselves; you just need them to be stable and secure without using unnecessary material making either of them too sturdy. Start simple, take a splash mould, satisfy yourself up to that stage. Then make the splash part (with a thick gel so you can modify the texture) and then make your final mould. You'll be a dab-hand by then. Use Uni-Mould when you make the final mould; it will be much thicker and will need a vinylester gelcoat so Uni-Mould is definitely the way to go. >> P.S Where are all the PDF from the resource section? At the moment we just have the videos. We did have some PDFs (not related to honeycomb) but we're gradually updating a lot of this content. I'm afraid we don't currently have any tutorials or guides that relates to working with honeycomb although this is something that we plan to do fairly soon. >> Finally can you chime in on the issue of the posts, clips and attachment points on the back? Did you attach the image, I can't see it? There have been lots of discussions about mounting clips, I'm not 100% sure what your particular requirement is but if you can't find your answer already then please let me know some more about what you're trying to do. Thank you Matt for the more direct response. I think I am settled with the slash mold and going slower as opposed too trying to do a mold quickly. As for the clips, in my first post i left a link to a post with a few pictures of what we mean. ( http://www.talkcomposites.com/23154/CF-clips-for-car-dashboard ). What is the BEST way to make and attach the clips? Thank you again. This is a difficult one to answer because there isn't one right way and you generally need to adapt depending on what is available. In our experience (from when we started off life manufacturing carbon fibre car parts) we would look closely at a clip and work out not how to copy it exactly but how to copy what it needs to do. Often this would mean replacing the complex moulded clip with a simply metal bracket or fastener that does the same job. Generally the moulded plastic clips look the way they do because they're designed to be injection moulded right from the start. Trying to recreate an injection moulding in a moulded composite part can be extremely complicated and is usually unnecessary - you'll often find that a folded aluminium bracket bonded onto the inside of your part will work just as well. I did notice that early in this thread someone posted some links to clips on Alibab0/Google; actually, following this link there were some interesting clips and brackets listed that might give you some inspiration. Another possibility would be to take moulds off the original parts using RTV silicone rubber and then cast them in polyurethane.We have a toughened high strength polyurethane which is suitable for this type of work called Xencast P6. These could be moulded to have a larger bond area (like a flat flange at the bottom) and then bonded to the inside of your parts using a tough adhesive such as VuduGlu VM100. Thank you again for the reply, I guess my biggest question/concern would be the strength of a glued/bonded clip post curing. Obviously fused would be the strongest but is the right bonding process just as strong? We have all seen and probably tried to repair and glue back a broken clip and thought the repair would be permanent to find that it was mostly temporary and un-reliable so I am wanting to avoid the temporary unreliable bond on a costly CF replica or part! I don't know quite what you mean by 'fused' I'm afraid. Bonded (using the right adhesive) would be very strong, the clip would fail way before the bond would. When you're gluing a clip back on you're generally dealing with difficult to bond plastics (ABS, polyethylene) which would be a different story. Bonding an aluminium clip to an epoxy-based composite is far easier and more reliable.
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Pkzipper
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Group: Forum Members
Posts: 7,
Visits: 21
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+x+x+x+x+x+x+x+xHi. Don’t know if it’s relevant but I am currently doing an envelope bagging of the lock cover plate for my kit car ( waiting for the base coat to go tacky as I type this). The fixingings on this are just holes that a screw and cover go into. I’ve taped bits of stirring stick onto the back and filled the hole with mould wax so there should be no leakage and should be easy to remove from the back later. Hi, We've not been online over the weekend but basically Hanaldo has stated what would be the EC opinion anyway. It sounds like you're aware of the choices you have (in removing the texture from your original parts) which are to: 1. Sacrifice the original (by filling and smoothing out the texture).
This is quickest and most accurate (least distortion). Disadvantage of course is that it sacrifices the original. 2. Do a very thick gelcoat on the mould and then smooth out the texture in the mould.
This can offer a decent compromise allowing you to not sacrifice the original but to reduce the workload and cost and reduce the risk of distortion however flatting and polishing 'in the negative' is much more difficult, it's hard to see when you've got it right and you're often flatting on the inside of a concave plain which is much more difficult. Also, although you reduce the risk of distortion from going back and forth between part and mould you will introduce some inaccuracy by necessarily flatting down to the lowest point in the texture rather than being able to build up to the highest point or striking a mid point (as you would with options 1 or 3. 3. Take a quick (splash) mould off the original and then make a GRP copy of the original (a splash part) which you can modify, including taking any texture out.
This gives you the most scope for 'correction' and avoids sacrificing the original. Disadvantages are that it's the most work, the most cost (in materials) and can introduce distortion because you're turning the whole process through twice by the time you get to the finished part. Moulding can be a bit like 'Chinese Whispers' and some distortion can creep in if you're not careful. There's pros and cons to all approaches; choosing the right one is subjective and depends on your priorities. Hello and thank you Matt, Option one is the one I need to be prepared for as some of the original components have high value. I am left with the choice of two and three. I appreciate you cannot pass on definitive direction as there is not one right way nor do you want the blow back if it fails. I am leaning towards option three as from what I am hearing sanding a positive is way easier than sanding a negative mold. Also, sanding and polishing pattern coat primer and high gloss is way easier than gel coat! Its just the flex and distortion issue. A well made mold should eliminate the possibility of distorting the part but the finish would be suspect. The splash mold is my concern and I know it is my choice but I am just looking for reference. Splash mold's, as supposed to permanent molds, make a quick replica of the original but that original could be effect if the mold is too flimsy but how do you gauge that? Or do you build a stronger mold from glass to be safe but at what cost? What about cost effective backing media like Plaster or something that is cheap and rigid? I would think it might be better in the case of making a working replica to focus on strengthening it for it not to warp while its being worked but with what? Plaster is heavy but does not expand. Silicone is too flimsy and expanding foam well is expanding and could/would it distort the form while expanding. Am I over thinkin this?? Finally can you chime in on the issue of the posts, clips and attachment points on the back? Thank you again P.S Where are all the PDF from the resource section? I only see the videos. I want to look at the PDF that had reference to using honeycomb. >> Am I over thinkin this?? Yes, definitely! Forget using weird and wonderful alternatives to GRP; plasters, silicones - they're not the way to do this. It sounds like you just need some experience with GRP; conventional polyester gelcoat, chopped strand matt and polyester resin layup. Distortion is caused by shrinkage, a good laminator knows to take their time, building up layers one at a time over a period of a few days, this will eliminate most shrinkage issues. The thickness of the splash moulds and splash parts will tend to determine themselves; you just need them to be stable and secure without using unnecessary material making either of them too sturdy. Start simple, take a splash mould, satisfy yourself up to that stage. Then make the splash part (with a thick gel so you can modify the texture) and then make your final mould. You'll be a dab-hand by then. Use Uni-Mould when you make the final mould; it will be much thicker and will need a vinylester gelcoat so Uni-Mould is definitely the way to go. >> P.S Where are all the PDF from the resource section? At the moment we just have the videos. We did have some PDFs (not related to honeycomb) but we're gradually updating a lot of this content. I'm afraid we don't currently have any tutorials or guides that relates to working with honeycomb although this is something that we plan to do fairly soon. >> Finally can you chime in on the issue of the posts, clips and attachment points on the back? Did you attach the image, I can't see it? There have been lots of discussions about mounting clips, I'm not 100% sure what your particular requirement is but if you can't find your answer already then please let me know some more about what you're trying to do. Thank you Matt for the more direct response. I think I am settled with the slash mold and going slower as opposed too trying to do a mold quickly. As for the clips, in my first post i left a link to a post with a few pictures of what we mean. ( http://www.talkcomposites.com/23154/CF-clips-for-car-dashboard ). What is the BEST way to make and attach the clips? Thank you again. This is a difficult one to answer because there isn't one right way and you generally need to adapt depending on what is available. In our experience (from when we started off life manufacturing carbon fibre car parts) we would look closely at a clip and work out not how to copy it exactly but how to copy what it needs to do. Often this would mean replacing the complex moulded clip with a simply metal bracket or fastener that does the same job. Generally the moulded plastic clips look the way they do because they're designed to be injection moulded right from the start. Trying to recreate an injection moulding in a moulded composite part can be extremely complicated and is usually unnecessary - you'll often find that a folded aluminium bracket bonded onto the inside of your part will work just as well. I did notice that early in this thread someone posted some links to clips on Alibab0/Google; actually, following this link there were some interesting clips and brackets listed that might give you some inspiration. Another possibility would be to take moulds off the original parts using RTV silicone rubber and then cast them in polyurethane.We have a toughened high strength polyurethane which is suitable for this type of work called Xencast P6. These could be moulded to have a larger bond area (like a flat flange at the bottom) and then bonded to the inside of your parts using a tough adhesive such as VuduGlu VM100. Thank you again for the reply, I guess my biggest question/concern would be the strength of a glued/bonded clip post curing. Obviously fused would be the strongest but is the right bonding process just as strong? We have all seen and probably tried to repair and glue back a broken clip and thought the repair would be permanent to find that it was mostly temporary and un-reliable so I am wanting to avoid the temporary unreliable bond on a costly CF replica or part! I don't know quite what you mean by 'fused' I'm afraid. Bonded (using the right adhesive) would be very strong, the clip would fail way before the bond would. When you're gluing a clip back on you're generally dealing with difficult to bond plastics (ABS, polyethylene) which would be a different story. Bonding an aluminium clip to an epoxy-based composite is far easier and more reliable. I generally refer to fused as laminated but I differentiate laminating as layering and fusing as combining parts that have not been cured. Thanks again for input on the strength.
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