How to cast this shape?

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How to cast this shape?

Author	Message
Hanaldo	Hanaldo posted 10 Years Ago HOT Topic Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Hello, I have just bought some silicon mold making rubber and some epoxy casting resin which I would like to use to replicate some tabs on some parts I am making. The original part has locating tabs on the inside, and as I am making this part out of carbon fibre, I will need to replicate the tabs then bond them to the new part. I have never used silicon molds or casting resin before, though it seems pretty straight forward. My issue is with the shape of the tab: I think this should be very easy to mould, but I am forecasting issues with casting. Due to the shape, the resin is not going to stay where I intend it to stay (damn you gravity ). The only way I can see around it is to place the mold on it's side, then create a dam next to the mold with coreflute or something, then fill this up with resin. Is there an easier way of doing it that I am overlooking? Thanks for any help, sorry if my explanation doesn't make much sense. Cheers, Martin.
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carbonfibreworks	carbonfibreworks posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Build a small box around the tab using corex and secure with hot glue, make sure you have used sufficient glue so the box will not leak .Spray a bit or release on the tab and then fill with silicone (it may work OK without release) .Makes sure you degas your silicone and if you purchased your silicone from EC it will be clear ,this is a great help when making your cut lines on your new mould Chris www.carbonfibreworks.co.uk Edited 10 Years Ago by carbonfibreworks
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Hmm, don't think I expressed what I meant very well. Molding the tab should be easy, that's not a problem. The thing I'm not understanding is how to cast the part IN the mold, without producing a very thick part. Obviously the resin is going to want to level itself out. With the shape of the tab, that is going to cause me issues when casting, as I don't want to end up with a big block of resin.
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carbonfibreworks	carbonfibreworks posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Why will you have a thick part ? it will be an almost exact replica of the original tab. Chris www.carbonfibreworks.co.uk
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Ohhhh I might have just clicked onto what you mean haha. Would you replicate the WHOLE tab? So do a 2 part mold? The silicon stuff that I bought is brush-able or pour-able, so I was just going to make a glove mold... This is so much harder to explain than it should be haha. So if I was to do it as a block mold, I assume I then need to cut the mold in half to get it off? Edited 10 Years Ago by Hanaldo
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carbonfibreworks	carbonfibreworks posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Make it as a block mould in silicone and make cut lines through the part with a scalpel to help release the part, plenty of videos on youtube showing the cutting technique. Regards Chris www.carbonfibreworks .co.uk
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Right, all studied up and on the same wave length! Thanks for that mate, that will work much better than what I wanted to do.
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