Hi folks, Found a interestimg Video from a german Foundry how they use the basin with a plug to prevent air mix into the molten Amluminium. https://youtube.com/shorts/MR5sWxtCTuk
Interesting video, thanks. Seems like they also use the technique to fill this 40kg mold. Do you know if the sand is 3D printed? It looks like that to me.
They use this technique on every single casting I've seen from them. Yes, they do the 3D sand printing for the cores and molds. When they do my Motorbike cylinder I'll get somr pics and videos from them. Then I can show you the whole process and how they do the gating, riser and so... From some pics I allso know, that they use ceramic filters every time. I hope they will cast it soon
Similar offset pouring basins and plugs are shown in Prof. John Campbell's Mini Casting Handbook. One of our members, @oldironfarmer, did something similar but instead of a plunger/plug that has to be pulled his diy approach was to use a little piece of styrofoam to plug the sprue with, which takes a second to burn out, long enough to get his pouring basin nice and full without needing a second man or some elaborate mechanism to pull the plug. https://forums.thehomefoundry.org/index.php?threads/foam-plug-in-a-pouring-basin.668/ I use offset pouring basins too and fwiw if the basin and sprue are sized appropriately for the crucible being used, I've never had any trouble getting mine filled and the sprue primed and running full almost instantly without needing any plug. Jeff
There are more books and handbooks about casting out in your country, than in my own It's a little bit hard to find good books about foundry work in Austria/Germany. The only Book I have is a german Foundry "school book", but there is everythin extremely theoreticaly, nothing about how to do... lots of calculating, but not much about the real life. A really german book
Prof. John Campbell's books have the same problem, but when he decides to give an answer its also very impractical, ive listen to his lectures and he often says that you need the gating simulators to really use his system well... Basically he is only talking to the very highest level of metal casters , V/r HT1
This reminds me of a story he wrote in his book Castings Second addition. The author recalls that in the early days of the Cosworth process, a small aluminium alloy pipe casting was made for very high pressure service conditions. At that time it was assumed that the mould should be filled as slowly as possible, arriving at the top of the pipe just as the melt was freezing to encourage directional feeding. When the pipe was finally cast it looked perfect. It passed radiographic and dye penetrant tests. However, it failed catastrophically under a simulated service test by splitting longitudinally, exactly along its top, where the metal streams were assumed to join. The problem defeated our expert team of casting engineers, but was solved instantly by our foundry manager, George Wright, our very own dyed-in-the-wool foundryman. He simply turned up the filling rate (neglecting the niceties of setting up favourable temperature gradients to assist feeding). The problem never occurred again. Readers will note a moral (or two) in this story. There is theory, and there is practical experience.
I've patched them up a few times but I'm stilling using the two original ones I made in 2019 at the start of this thread. https://forums.thehomefoundry.org/i...le-offset-pouring-basin.688/page-4#post-52874 I added two larger ones similar to the style Jeff posted. They were a great addition for the quality of my castings. Best, Kelly
I still wonder how big to make the basin and gating since I normally sand cast, hand-carving the basins into the cope. At the second to last cupola furnace iron pour, I used the 'house' pouring cups and sprue drill bit and got successful pours from 3 to 12 pounds. We had one small 2-up drink coaster pour fail and attributed that to some slag getting in the system. The molds typically have a pouring cup and vent cup pasted on top of them and a combination of molded and hand-tooled gating. I've messed with the OpenSCAD calculator https://forums.thehomefoundry.org/index.php?threads/parametric-filling-system-model.2274/#post-46592 but don't feel like I really know enough to set everything, I am just changing values until it looks like perhaps it will work.
