2 Part Moulding - Questions

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2 Part Moulding - Questions

Author	Message
Jack.Strong	Jack.Strong posted 13 Years Ago HOT Topic Details
Group: Forum Members Posts: 52, Visits: 549	Hi. So i am making my 2 part mould at the moment, having watched a lot of videos. Theres a few things I dont get; The need for a small radius at the interface. I would say to help demoulding and laying of the cloth, but surely it will transfer as an inclusion to the final shelled part ? Following my diagram below shows the square plug, with flanges added, 1 side of the mould made from that flange, the 2nd side made off the 1st, the two moulds having cloth layed in and mounted together. Ok so in this process I see two problems and would really appreciated someone explaining; The part needs to be the same outer dimension but if I am laying cloth between the flange then I am increasing the size of the part ? With the 1st mould, could i take it off the plug, then tidy up the 1st mould, then reattach it to the plug, fill the edges with plasticine and then make the 2nd mould ? Thanks for the help. Will post photos up shortly.
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Matthieu Libeert	Matthieu Libeert posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	Hi, Good thinking nice to see someone thinking a lot before doing stuff I don't remember if your mould was open at one side? By coincidence I've seen this video yesterday, Could be a way if you have an open mould?! Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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Jack.Strong	Jack.Strong posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 52, Visits: 549	Like how he cuts the wetted cloth with a blade to remove the over hang of the cloth. My 2 part mould is a bit to thin to be able to do that final stage.
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wozza	wozza posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 688, Visits: 5.4K	Hi Jack, assuming that this is the Duct project from your earlier post. I believe you plan to use an internal and external mould? So in essence a pressure mould. Assuming this is because you are wanting a "gloss" finish on both surfaces. Is this your plan? Form a buck to the internal dimensions. Cover in sheet wax to allow for the thickness of the reinforcement/part. Make a split mould from this buck. You now have a 3 piece male and female mould with a 1mm (approx) gap between the two. Lay reinforcement into the female moulds place the male mould (buck) into female moulds and clamp together. I tried a similar process and failed. When you mould off sheet wax the surface finish is far from perfect and the sheet wax will vary in thickness. As a result by the time you have sanded and polished the surface of the mould to a high gloss you no longer have the same gap ie you have made the mould bigger (only slightly I know) You then lay your reinforcement into the mould and clamp everything together. Because the dimensions of the mould have changed you no longer have even pressure across the the mould surface resulting in a far from perfect finish on the part when you de- mould. Well that's what happened when I tried it. In the end I had to have aluminium moulds machined, not cheap I can tell you. I will have to sell 200 plus parts just to cover the cost of the moulds. Regards Warren Carbon Copies Ltd
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Jack.Strong	Jack.Strong posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 52, Visits: 549	Reluctantly I have gone away from the internal mould direction for now, thought loads about problems i could incur going that way and its just not something I want to attempt just yet. Matthieu, I have watched some of the other series of videos and they dont put a radius on the mould at all. Wreckon i could get away with not having them ? Here is a picture i took last night, so plasticine mould almost finsihed. Anyone recommend a chemical that will get the plasticine residue off the the plug but not remove the bulk of it ? Edited 13 Years Ago by Jack.Strong
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_GABBER	_GABBER posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 41, Visits: 646	Hi, how much space there is between the two molds? Why you don't resin with molds open, in a mold you cut fiber like the flange, in the other you cut fiber 1 cm longer....then you close molds and you have a mono piece? I usually do like this You can also put a tubuar nylon between the molds before close them, and pressure it I hope you get the idea despite my bad english Edited 13 Years Ago by _GABBER
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Jack.Strong	Jack.Strong posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 52, Visits: 549	The thickness of the plug is 25mm Could you explain the first bit. I am going to make two open moulds. Then fibreglass each, let cure, then join together. Edited 13 Years Ago by Jack.Strong
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_GABBER	_GABBER posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 41, Visits: 646	you make the 2 molds. you fiberglass each, but one has fiber up to the edge, the other has fiber longher. If you do like this, when you close molds (before cure them), the fiberglass of the 2 pieces join together
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Jack.Strong	Jack.Strong posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 52, Visits: 549	Anyway could you please draw a diagram, or show photos of it ? bit puzzled by your wording Edited 13 Years Ago by Jack.Strong
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Warren	Warren posted 13 Years Ago HOT Post Details
Group: Administrators Posts: 214, Visits: 782	quite a few solvants will dissolve plasticine so just wipe over the plug to clean it. Its a bit late now but you could have used sign board to do the flanges easier than the plasticine, then just use plasticine for the joins/curves.
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