Gadgetory

so you might have seen our last attempt at making a heat sink where we took a reciprocating saw to a block of aluminum with what could best be described as limited success but of course persistence is the name of the game here at LMG so we went through the YouTube comments which were full of suggestions about casting our own heat sink from molten aluminum and decided to set about doing it but is that really the kind of thing that you can do with a hundred dollars worth of supplies and an empty warehouse well there's only one way to know for sure Brow's privately and securely with tunnel there the simple VPN app try tunnel bear for free at the link in the video description so casting then I guess we'll need a couch to know we're talking about the kind of casting where a molten material is poured into a mold so that it solidifies in the desired shape there are a couple of important elements that you need a foam or plastic replica of the intended finished design and a material that you can mold around it that can hold its shape the primary design considerations for our heat sink for how easy it would be to cast and how much heat it could dissipate we kept it as simple as possible in SolidWorks with the two pieces coming off the heatsink being to allow for the metal to be poured into one end and the gases to vent out of the other and the mold had to be orientated in such a way that the bottom would be the most likely surface to have a smooth flat finish although the fins ended up thicker than we'd have liked when it comes to heat sinks size matters and we calculated a theoretical heat dissipation of over 200 watts so then we went ahead and printed our design using PLA plastic at a hundred and three percent size to account for the shrinkage of the aluminum during cooling we chose PLA because it's made from corn so when it burns it shouldn't poison us to improve our odds of success we needed casting grade aluminum but buying that stuff new is pretty expensive fortunately there's a large source of casting grade aluminum the scrap yard so we headed there and picked out our victim extracting the engine out of this 2002 Toyota Yaris back in the shop we took apart the engine cleaned off the dirt and chopped it into pieces small enough to melt we used foam men to extend our pouring and venting holes then we mixed up clay sand and water until it reached a consistency where it was pliable but able to hold its shape this mixture called green sand was packed around the 3d print and then baked for a couple of minutes to partially melt the plastic and to harden the clay this whole process is called lost PLA casting we then placed the aluminum scraps that we had into a graphite crucible which is basically a large cup that can withstand really high temperatures and set about melting the metal in a crude furnace that we made out of fire bricks one of the best and worst things about aluminum is that when it's exposed to air it almost immediately forms an aluminum oxide layer on the surface this is good for preventing further corrosion but it makes it very annoying for melting so it's important when casting then to remove the aluminum oxide layer that floats to the top called dross so that it doesn't contaminate the finished cast with the dross removed we were ready for our first pouring attempt though it should be noted we weren't sure how much of the PLA had actually melted on this one turns out not much clearly the aluminum barely made it into the mold and wasn't able to melt much of the plastic in the process so to troubleshoot then we made a different riser design out of foam so that the aluminum would be able to enter across the entire top of the mold greensand melt purify and pour again and we ended up once more with a face only a mother could love so we moved on then from lost PLA casting to lost foam casting which is an extremely popular and much easier way of creating molds do to the low melting point of foam when the aluminum is poured in it immediately melted away and fills the space in theory our for mold wasn't perfect by any means but we were cautiously optimistic that it would work so fire melt and pour again and we get to see what kind of a result we were going to get unfortunately this wasn't a massive success either although the foam did melt away and we were able to create a good base layer and even where the mounting plate would be was fairly well done we simply didn't have enough static pressure to force the molten metal up into the thin shapes we could solve this by creating a much taller riser but by this point the time crunch had become real and our engineering department realized that he needed to produce something usable or I might melt him down so he made a clay and firebrick sandwich and assemble the mold using a method that bears more purpose using a method that bears more resemblance to grade one art class than to precision crafting to ensure on this the final attempt that the metal would thoroughly melt the furnace was remade and heated until the entire crucible was red hot upon pouring the aluminum into the mold it started bubbling from the steam escaping from the clay making the metal of the finished products more porous a problem we hadn't had before when we were using green sand so then with a bit of massaging from the reciprocating saw to make it fit on a motherboard it was finally ready to mount the processor chosen was an Intel Q 6600 mainly because the old asus motherboard it was on was the only one where the heatsink didn't interfere with the VRM and to help fill in the air pockets on the bottom of the heat sink we added a more than generous dollop of thermal paste topping off the creation with a handful of zip ties and this was actually the first time I laid eyes on what three of my staff had been doing all week I don't know how anything could have been worse than what I was expecting but this may have achieved it I mean the name of the series is getyou heat sinks and I guess mission accomplished there with all of that said testing and i-264 turned out better than expected and sketchy heat sink number two was able to keep the CPU reasonably cool for a fairly long time although this is likely more to do with its large thermal mass then its ability to dissipate heat ambitious but rubbish 10 out of 10 IGN so yeah in the end this turned out to be the no man's sky of heat sinks sure we had high goal set and we believed with the resources we had we could pull it off but it took three times longer than originally planned and the end result performs poorly looks bad and has almost none of the features that we said it would have in the beginning so then all that's left to say is thanks in advance to the metalworking experts who by now has filled the comments with advice we will bear it in mind for the next installment then of sketchy heat sinks FreshBooks is the small business accounting software it's built from the ground up for how you work as a freelancer or a small business owner and it's the simple way to be more productive and organized not to mention to get paid more quickly and on your own terms you can take deposits you can get paid faster you can create and send professional-looking invoices in less than 30 seconds you can track your expenses you can even see when your client has seen your invoice to put an end to that oh did you send it no I didn't see it la blah blah nonsense and you can even take your payment directly through fresh books if all that sounds awesome you want to stop dinking around with complicated accounting software then try fresh books for 30 days for nothing at first ebooks.com slash tech tips and enter tech tips in the how did you hear about us section so thanks for watching guys if you just like this video hit the dislike button but come on where's your sense of fun but if you liked it hit the like button get subscribes maybe consider checking out where to buy the stuff we featured I mean what would that even be like scrap aluminum at the link in the video description and also the link to our community forum and our merch store which has cool t-shirts just like this one