Issues with what i think is shrinkage!

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Issues with what i think is shrinkage!

Author	Message
Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Then do 7-8 layers of the 300g. Your mould is no where near strong enough to demould a part like that, especially on the flanges. You need to change the angle of those mounting points. Just a small change would do (think 1 degree), if you use filleting wax to taper them then this would help immensely. Alternatively what I have done recently on a part with no draft angle is build a nut into the mould, so that you can thread a bolt in behind the problem area and push it out from behind. Of course you need to take care to seal the nut to prevent resin binding the threads etc.
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Undercover	Undercover posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 9, Visits: 46	Im using 300g csm, the only stuff i have available to me! I only done a few layers then more would be added once the part was demoulded. But thats where im having issues.. I feel the wax is enough although i will add more just to be safe.. Once i can get part of it to release its all comes out with a bit of force. So to me, releasing is not an issue, not to a degree anyway. Whats peoples beat idea's on how to solve this?
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Also, 3-4 coats of wax is lean. I would be going 8-10.
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	For one, 2 layers is no where near enough. You need one layer of 100 or 225g csm and let that cure for 5-6 hours. And then AT LEAST 4 layers of 450g csm, preferably 5. Then, your issue with not getting the part back into the mould is very likely because those bolt holes are parallel sides to each other and so are too tight a fit. These are quite a tricky part to make, much harder than you would expect, simply because of those mounting points.
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Undercover	Undercover posted 9 Years Ago HOT Topic Details
Group: Forum Members Posts: 9, Visits: 46	ive been attempting to make a mould. I got the part and cleaned it up, gave it 3 or 4 coats of #8 release wax. I also gave a few coats got the surface that the plug was sitting on. I gave it a good coat of tooling gelcoat, bit thick in places but a good coverage all over. I taped up any holes where i didnt want gelcoat or resin going. I let that pretty much go off, so there was still a little bit of tackiness left. And starting laying. About 2 layers thick but up to 4 maybe 5 and intricate areas. I let it all dry and attempt to demould. As you can see from the picture, didnt go too well. Once i did get it removed i attempted to put the part back in but it wouldnt fit Mould seemed smaller than part. Any ideas? Attachments image.jpeg (348 views, 1.00 MB)
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