Aluminum mold for prepreg

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Aluminum mold for prepreg

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quinn	q quinn posted 6 Years Ago HOT Topic Details
q Group: Forum Members Posts: 155, Visits: 992	I'm about to start machining my mold but I have a few concerns. The composite part is an 800m long tapered tube. 46mm diameter at one end, 30mm at other end. The closed mold is 75mm square by 800mm long. This means the mold walls will be as thin as 15mm at one end and as thick as 22mm at other end. One concern is the time it takes for this big chunk of aluminum to heat up, the other concern is uneven heating, thinner walled end heating up first. How should I approach this with my ramp cycles? Just go slower in general? Hold temps longer? I'm really not sure what to expect for how long it's gonna take for it to heat up. If the varying wall thickness is gonna be a big problem, I can do some machining on the outside to even it out, but would rather not if it isn't needed. First few parts will be done with vacuum bag so the laminate will be exposed to the heated air but later on I'll be trying silicone expanding plug so I'm sure that will change things as far as heating. Any advice on how to approach this? Thanks
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Lester Populaire	L Lester Populaire posted 6 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x quinn - 1/3/2019 7:33:41 PM Meant 800mm long, not 800m absolutely no issue with the different wall thickness. Aluminum has a heat transfer that is really good which means that you will get a uniform temperature. I would just make the soak times longer to give it time to get to temperature. No need to get slower, if anything you might go slightly faster as the big mass will slow things down.
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quinn	q quinn posted 6 Years Ago HOT Post Details
q Group: Forum Members Posts: 155, Visits: 992	+x Lester Populaire - 1/3/2019 8:21:52 PM +x quinn - 1/3/2019 7:33:41 PM Meant 800mm long, not 800m absolutely no issue with the different wall thickness. Aluminum has a heat transfer that is really good which means that you will get a uniform temperature. I would just make the soak times longer to give it time to get to temperature. No need to get slower, if anything you might go slightly faster as the big mass will slow things down. Great thanks! I did pick up a few extra temp sensors. maybe ill bore a couple holes in tbe thickest area of the mold to insert temp sensor and monitor
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Lester Populaire	L Lester Populaire posted 6 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x quinn - 1/3/2019 8:31:19 PM +x Lester Populaire - 1/3/2019 8:21:52 PM +x quinn - 1/3/2019 7:33:41 PM Meant 800mm long, not 800m absolutely no issue with the different wall thickness. Aluminum has a heat transfer that is really good which means that you will get a uniform temperature. I would just make the soak times longer to give it time to get to temperature. No need to get slower, if anything you might go slightly faster as the big mass will slow things down. Great thanks! I did pick up a few extra temp sensors. maybe ill bore a couple holes in tbe thickest area of the mold to insert temp sensor and monitor If you have the opportunity to do so this will give you some very valuable bits of information. just have a look at the time as well and make a graph over time to get a better feeling for the next time.
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