Can stock parts be used in place of molds? (Spark plug covers etc)

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Can stock parts be used in place of molds? (Spark plug covers etc)

Author	Message
Orlandodc2	O Orlandodc2 posted 7 Years Ago HOT Topic Details
O Group: Forum Members Posts: 4, Visits: 29	Hello. I have a question. Can I use stock car parts as the mold itself for creating carbon fiber parts? Some of the parts I want to currently make are: Spark plug cover Air box lid Car emblem Interior trim body pannels Stock mud flaps I currently have those parts but I'm not sure if I need to create a mold off of the original part and then create the carbon fiber part off of the mold, or If I can just use the original part as my mold. I will be doing the resin infusion method to create the carbon fiber parts. Thank you in advance.
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Hanaldo	Hanaldo posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	You need to make a mould off your stock parts, then make your carbon parts out of that.
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oekmont	oekmont posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	It might be possible for some parts, with some additional finishing work for your parts. But usually: no. It is as simple as that. There are a number of reasons why. Only to name the most crucial: your new part would be slightly bigger than the original, and therefore will not fit in many applications. And with vacuum infusion you would create a whole lot of additional problems, like impregnating the back side of your original part. This is a typical composites beginners dream, but usually no good idea.
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Orlandodc2	O Orlandodc2 posted 7 Years Ago HOT Post Details
O Group: Forum Members Posts: 4, Visits: 29	Lol and a beginner I am. Thank you guys for the responses.
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Steve Broad	Steve Broad posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 408, Visits: 4.1K	Generally, I agree that making a mould is 'usually' the best way. However, there are occasions when the original part can be used. For example, I recently made carbon door skins for my Lotus Elan. As I was gluing these on to the existing fibreglass doors there was no issue with the minuscule difference in radius. Another item I have made using this technique is a single skinned boot lid. Again, the minimal increase in size - approx 1-2mm wider and deeper - wasn't an issue in my case. This method works best with wet laying without vacuum, unless the original part is strong enough to resist deformation caused by vacuum bagging. Likewise, prepreg will also work if the original part can survive both heat and pressure :-) The only issue with this method is, as the inner surface of the carbon is usually in contact with the 'mould', the surface finish will need a little work :-)
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oekmont	oekmont posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	An elan has very British tolerances anyways. The original bodywork had tolerances within an inch...
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Orlandodc2	O Orlandodc2 posted 7 Years Ago HOT Post Details
O Group: Forum Members Posts: 4, Visits: 29	+x Steve Broad - 4/26/2018 10:49:12 AM Generally, I agree that making a mould is 'usually' the best way. However, there are occasions when the original part can be used. For example, I recently made carbon door skins for my Lotus Elan. As I was gluing these on to the existing fibreglass doors there was no issue with the minuscule difference in radius. Another item I have made using this technique is a single skinned boot lid. Again, the minimal increase in size - approx 1-2mm wider and deeper - wasn't an issue in my case. This method works best with wet laying without vacuum, unless the original part is strong enough to resist deformation caused by vacuum bagging. Likewise, prepreg will also work if the original part can survive both heat and pressure :-) The only issue with this method is, as the inner surface of the carbon is usually in contact with the 'mould', the surface finish will need a little work :-) I see, maybe i'll just do the spark plug cover that way and if I dont like the way it came out or the fitting that just means I'll just a carbon fiber mould to use with the infusion. lol so win win. Thanks
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oekmont	oekmont posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	Well.... If you want to make a mould, you should think about adding some flanges, especially when going for infusion. So a part, that came out bad will make a bad mould as well.
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Steve Broad	Steve Broad posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 408, Visits: 4.1K	+x oekmont - 4/26/2018 11:14:04 AM An elan has very British tolerances anyways. The original bodywork had tolerances within an inch... If it was made on a good day :-) However, even cars built to closer tolerances can cope with carbon panels that are less than 1mm thick :-)
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