Mould in MDF - how to do..

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Mould in MDF - how to do..

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Leif Lundin	Leif Lundin posted 4 Years Ago HOT Topic Details
Group: Forum Members Posts: 2, Visits: 66	Hello, I am working on a mold in MDF which I will then use with the resin vacuum injection method with epoxy and carbon fiber fabric. The surface on the MDF is perfect now after the cnc milling but lacks the surface finish to start molding. How do I not destroy the current surface layer as I prepare for casting? Have bought Easy Composites: Pattern-Coat Primer Pattern-Coat Hi-Gloss Easy-Lease Mold Cleaner Easy-Lease Chemical Release Agent GC50 Epoxy Compatible Clear Polyester Gel Coat I will use laminating epoxy together with 600gr Twill carbon fiber fabric with a Divinycell foam core. Some questions: 1. Are there any shortcuts or do I have to do all the steps with the products as above? 2. How long do you think this takes from CNC milled MDF to finished form? 3. How much will be spent on each product as above if the shape is 600 * 2200mm large
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Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	+x Leif Lundin - 2/25/2020 8:09:25 AM Hello, I am working on a mold in MDF which I will then use with the resin vacuum injection method with epoxy and carbon fiber fabric. The surface on the MDF is perfect now after the cnc milling but lacks the surface finish to start molding. How do I not destroy the current surface layer as I prepare for casting? Have bought Easy Composites: Pattern-Coat Primer Pattern-Coat Hi-Gloss Easy-Lease Mold Cleaner Easy-Lease Chemical Release Agent GC50 Epoxy Compatible Clear Polyester Gel Coat I will use laminating epoxy together with 600gr Twill carbon fiber fabric with a Divinycell foam core. Some questions: 1. Are there any shortcuts or do I have to do all the steps with the products as above? 2. How long do you think this takes from CNC milled MDF to finished form? 3. How much will be spent on each product as above if the shape is 600 * 2200mm large If dimensional tolerance is critical, you will have to mill the MDF slightly undersize to allow for the coatings. I would allow 1-1.5mm for a coat of the Patterncoat Primer and a coat of the Hi-Gloss. If that sort of size difference isn't critical then just spray the primer, flat it down with 320g and then spray the high gloss. If you are adequate at spraying, the surface will come out well enough to either be ready to go or just need a quick flat and polish. How long it will take is kind of a how long is a piece of string question. It depends totally on your skill set. For something that size, I would expect it would take me 20 minutes to prime it, a couple hours cure time, an hour of sanding, 20 minutes to gloss coat it, an overnight cure, then an hour to flat and polish it. So a day job. Also hard to answer - depends on the equipment you are using, how many coats you need to do to get the surface you are after etc. typically for correct coverage, you need about 650g per square meter. So say about 1kg each of the primer abd gloss coats. Release agent will go a very long way, you'll probably use 20ml.
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Leif Lundin	Leif Lundin posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2, Visits: 66	+x Hanaldo - 2/25/2020 8:55:58 AM +x Leif Lundin - 2/25/2020 8:09:25 AM Hello, I am working on a mold in MDF which I will then use with the resin vacuum injection method with epoxy and carbon fiber fabric. The surface on the MDF is perfect now after the cnc milling but lacks the surface finish to start molding. How do I not destroy the current surface layer as I prepare for casting? Have bought Easy Composites: Pattern-Coat Primer Pattern-Coat Hi-Gloss Easy-Lease Mold Cleaner Easy-Lease Chemical Release Agent GC50 Epoxy Compatible Clear Polyester Gel Coat I will use laminating epoxy together with 600gr Twill carbon fiber fabric with a Divinycell foam core. Some questions: 1. Are there any shortcuts or do I have to do all the steps with the products as above? 2. How long do you think this takes from CNC milled MDF to finished form? 3. How much will be spent on each product as above if the shape is 600 * 2200mm large If dimensional tolerance is critical, you will have to mill the MDF slightly undersize to allow for the coatings. I would allow 1-1.5mm for a coat of the Patterncoat Primer and a coat of the Hi-Gloss. If that sort of size difference isn't critical then just spray the primer, flat it down with 320g and then spray the high gloss. If you are adequate at spraying, the surface will come out well enough to either be ready to go or just need a quick flat and polish. How long it will take is kind of a how long is a piece of string question. It depends totally on your skill set. For something that size, I would expect it would take me 20 minutes to prime it, a couple hours cure time, an hour of sanding, 20 minutes to gloss coat it, an overnight cure, then an hour to flat and polish it. So a day job. Also hard to answer - depends on the equipment you are using, how many coats you need to do to get the surface you are after etc. typically for correct coverage, you need about 650g per square meter. So say about 1kg each of the primer abd gloss coats. Release agent will go a very long way, you'll probably use 20ml. Hi! Thanks for your answers! Don't know if I thought wrong, but read on Easy Composite's website that in a mold you want to achieve as hard and polished a surface as possible so that you can use the mold many times with as good results. Should I use EG60 Epoxy Tooling Gelcoat in the MDF form instead of Pattern-Coat Primer and Pattern-Coat Hi-Gloss? The mold consists of 2 layers of MDF which are glued together of which the upper layer is CNC milled with the profile and shape of the splitter. The lower layer only becomes the bottom of the mold (top of the finished splitter). So it is the surface layer of the mold I should apply Gelcoat to which will then be sanded down in case of any runs or highlights, and finally polished, polished, polished.. Want to make sure I use the right type of Gelcoat for the mold! Do you put several layers of Gelcoat with grinding in between or how do you go about getting a top result?
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