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Hanaldo
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After two post cure cycles, it really shouldn't be moving at all anymore, you could leave it clamped to the plug for months and it would do very little.
Really you are better off deciding whether you can make this mould work, or are you better off starting again. One potential option is to clamp it in place, and provided that works well, you could then bond on your planks of wood with an adhesive and some fibreglass. This may have enough strength to hold it in place again. Not ideal, but would certainly do for a one-off.
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Fredrik Welen
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Yes that will work I guess and that was my thoughts too.. I think I can use this mold.. I will lay it on the plug to see were I´m at.. and then I will see what I can do with the surface..
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Fredrik Welen
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I caught the flue so updates are slow.. I layed the roof mold to the roof plug and it was not that bad actualy..  Since it is bent a bit it is a bit short and I am afraid that I will damage something if I force it over the roof plug. iI it is even possible. But as it looks right now I don´t think I have to ether.  It still is a little bit more bent then the original roof but not very much. Remember it rides on the front edge in this picture.  There is still hope..
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Fredrik Welen
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I started with the wet sanding of the mold surface. I started with dry 500 grit and my orbit sander and continued with 800 wet, 1000 wet, 2000 wet and even 3000 wet.
I had a professional product of chemical rubbing that I used with a professional polishing machine. I got the gloss but it didnt remove very much of the scratches.. The polishing compound is rely old too..
I will order some more polishing stuff from easy composites and see if I get a better result.. Have to wait for it though..
I have a layup question..
The roof is about 105 cm wide.. I will use a 125cm 200g twill wide fabric and cut it down for a surface layer, back it up with 100cm wide surplus 2/2 380 twill for 2 layers and a last layer of 200g twill also 100cm wide. 1160 grams total per square meter which will give me a thickness of about 1,2mm if I get it correctly
I have to extend the backing materials with a 5 cm strip.. Do I lay it up edge to edge or is it better to have some over lap? If I do overlap, it will be slightly thicker where the overlap is and I am afraid that it will be some kind of print through or deformation there.. Especially when I will be doing post cure heat cycles later.
One more question about the layup.. I am having nightmares of having bridging in the corners.. I have fusion fix GP spray adhesive but I am afraid of visible defects.. I will have the finished part clear coated though.. Is it rely possible to clean everything of after post cure cycles and have it clear coated without visible traces?
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oekmont
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Group: Forum Members
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If you are going to clear coat it afterwards, a bit of spray adhesive won't be a problem, as you should sand the surface of you part before painting. For the same reason, you should not waste your time, buffing your mold to the highest gloss. Just keep sure everything is flat. The glossier your mold, the easier the separation from the part, but a final sanding with 2000 and a light polish is already more than enough.
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Fredrik Welen
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Yeah I guess.. I got a fairly gloss finish so I bet it will be all right after clearcoat. But I realy like to get rid of all sanding traces from the orbital sander.. It is better to get the least amount of work to do for the painter to get a good end reault. I have yet to be supriced over how well a painters work is done.. I always seem to find something I need to fix or don´t like when they have done their job. Also the mold will last a bit longer with a high gloss finish and a better release as you said.. Thank you for the info about the tack spray mabe I will use it in the corners.. I will see how easy I think the layup will work out.. Have you any experiance of it after post curing your parts in the mold?
This hole process for me is not just to get the roof done. It is also a way to learn about how all materials work and to get the resaults I want to my standards and to get the ability to choose what is good enough and what´s not and how to fix it. If I learn the process of makeing parts I will be able to plan better and maybe sell some of the parts I am making. When the roof is done I will try and make interior panels and wider front fenders.. One step at a time though..
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oekmont
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Group: Forum Members
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If you still got sanding marks from the orbital sander, you didn't work well with the lower grits.
I highly doubt that your mold would last any longer with a better finish. At least not with proper release agent, and at the number of parts you might do.
If the marks are not to deep, sanding them of the final part will be much easier, as they are positive on the final part.
If you really work your mold to that high standard, you should definitely try inmold coating. No need to pay the painter then. I usually use standard 2 component clear laquer, and add the first layer when it is still slightly tacky. So no spray adhesive for the first layer.
post curing is pretty straightforward if you got the right equipment. Follow the instructions of your resin. But leave the bag closed for the process, as this reduces print through. In polyester molds post curing can only done to a certain degree. Maybe you have to do the higher temperatures off the mold.
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Fredrik Welen
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Group: Forum Members
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The sanding marks is due to debris clogging the paper.. I will try a few things to get rid of those when I am sandig down the repair I had to do because of trapped air bubbles showing in the surfice after the post cure process of the mold.
I was looking in to the clear gel coat as a first layer but that involves getting a special paint gun per easy composites instructions and the gel coat of cource, and the hazzel of spraying it and I bet that after relesing the final part some imperfection will show and repairing the gelcoat on the final part is something I´d like to avoid. Also my impression was that a regular cleracoat by a paint shop will ad a better UV protection. Also a clear paint will react the same way when it comes to washing the car and polish and waxing and so on.. To me the clear gel coat is adding to much of uncirtain grounds. After some more experiance I might try it out.. The only upside to the gel coat as I see it is that it can be used to stick the first layer of carbon to it. It will also save some time compaird to have a paint shop clear coat it.
But you are using standard clearcoat paint as a first in mold coat? Never heard of it or even thought about it but it will be both pretty cheap and easy.. I will try it on some thing smaller.
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Almand
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Group: Forum Members
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+xThe sanding marks is due to debris clogging the paper.. I will try a few things to get rid of those when I am sandig down the repair I had to do because of trapped air bubbles showing in the surfice after the post cure process of the mold.
I was looking in to the clear gel coat as a first layer but that involves getting a special paint gun per easy composites instructions and the gel coat of cource, and the hazzel of spraying it and I bet that after relesing the final part some imperfection will show and repairing the gelcoat on the final part is something I´d like to avoid. Also my impression was that a regular cleracoat by a paint shop will ad a better UV protection. Also a clear paint will react the same way when it comes to washing the car and polish and waxing and so on.. To me the clear gel coat is adding to much of uncirtain grounds. After some more experiance I might try it out.. The only upside to the gel coat as I see it is that it can be used to stick the first layer of carbon to it. It will also save some time compaird to have a paint shop clear coat it.
But you are using standard clearcoat paint as a first in mold coat? Never heard of it or even thought about it but it will be both pretty cheap and easy.. I will try it on some thing smaller.
Hi Frederik, dont try to apply 2K in mould, We are building kajak, and we have tried to do that with bad succes. You must apply 2K in very thinn mist for many times before the result is good. And even when its good we had problem. The best results is cg50 clear gelcoat, direct in mould and then use EC infusion epoyxy and slow hardener. If its done within 24 ours no problem.. Rgards Keld Denmark type your message
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Almand
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Group: Forum Members
Posts: 19,
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+x+xThe sanding marks is due to debris clogging the paper.. I will try a few things to get rid of those when I am sandig down the repair I had to do because of trapped air bubbles showing in the surfice after the post cure process of the mold.
I was looking in to the clear gel coat as a first layer but that involves getting a special paint gun per easy composites instructions and the gel coat of cource, and the hazzel of spraying it and I bet that after relesing the final part some imperfection will show and repairing the gelcoat on the final part is something I´d like to avoid. Also my impression was that a regular cleracoat by a paint shop will ad a better UV protection. Also a clear paint will react the same way when it comes to washing the car and polish and waxing and so on.. To me the clear gel coat is adding to much of uncirtain grounds. After some more experiance I might try it out.. The only upside to the gel coat as I see it is that it can be used to stick the first layer of carbon to it. It will also save some time compaird to have a paint shop clear coat it.
But you are using standard clearcoat paint as a first in mold coat? Never heard of it or even thought about it but it will be both pretty cheap and easy.. I will try it on some thing smaller.
Hi Frederik, dont try to apply 2K in mould, We are building kajak, and we have tried to do that with bad succes. You must apply 2K in very thinn mist for many times before the result is good. And even when its good we had problem. The best results is cg50 clear gelcoat, direct in mould and then use EC infusion epoyxy and slow hardener. If its done within 24 ours no problem.. Rgards Keld Denmark type your message Hi Frederik, dont try to apply 2K in mould, We are building kajak, and we have tried to do that with bad succes. You must apply 2K in very thinn mist for many times before the result is good. And even when its good we had problem. The best results is cg50 clear gelcoat, direct in mould and then use EC infusion epoyxy and slow hardener. If its done within 24 ours no problem.. Rgards Keld Denmark
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