This page contains a Flash digital edition of a book.
porated a system Miller describes. In one case, the supplier printed an insert overnight in ABS plastic for $250. For a separate job at another metalcasting facility, castings were provided within a week of receiving the model by printing only what was needed in PLA. Miller said there are two ways to


print tooling for metalcasting. Direct printing means printing or building what will be inserted into the picture frame or bolster. Indirect printing is to mass extrude, or quickly print, a large near net shape of the object that is then machined into shape. “Both ways work, it just depends


on the part and what you want to do,” Miller said.


Do-It-Yourself


Martin Foundry has found success with its scratch-built printer for made- to-order and replacement parts. “It’s been successful on orders that


would otherwise require milling out of a solid sheet of UHMWPE (ultra high molecular weight polyethylene),” Loerwald said. “It’s not quite as fast, but the material cost is next to nothing and we don’t have to buy any tooling or do it by hand.” Loerwald said that so far, the met-


alcasting plant will use the 3-D printer on about two jobs per month, but on each of those jobs, the company has saved at least $1,000. In one particularly successful part,


Martin Foundry printed out a piece to modify the aluminum matchplate for a bearing cap. “Te customer wanted to put an


oil groove on the bearing cap but we didn’t want to permanently modify the pattern,” Loerwald said. “We printed the corebox on the printer and produced it in two days rather waiting a week for new tooling. “It works great for when the pat-


ternshop is backed up. You can draw up the patterns, press print and move on.”


Stocking the Tool Box While 3-D printing seems like a


natural technology to market to met- alcasting, Miller admits many FDM printer manufacturers and equipment users are unfamiliar with the industry


Spectra 3-D printed these patterns for Flowserve in a PLA material for a titanium investment casting.


and the process. He has invited a few of them to casting facilities and exhibit shows to introduce them to the mar- ket, its opportunities and its needs. “Most of the folks that sell


the printers have never been in a foundry and have no idea what hap- pens in a foundry,” he said. “If you are looking for tools like these 3-D printers, I suggest engaging the peo- ple who you might consider buying a machine from and ask them to do a test print for your foundry. Once the printer people understand what we need in terms of surface finish, size and tolerances, the relationship works pretty well.” Miller said he currently sees a


break-even point for his parts to be two or three pieces. After three, it usually becomes more cost effective to make a tool. Tis basically matches up


to what Loerwald has seen at Martin Foundry, as well, but with so little overhead, the 3-D printer is a handy machine to have. “It’s not a magic machine, but it’s


another good tool to use,” Loerwald said. Miller agrees it is one tool of


many at the disposal of manufac- turers. But for the price point, the barrier to entry for FFF printing is small, and he urges his suppliers to “just get one.” “There is a cafeteria of choices.


There’s print for investment, print for sand, other additive manufac- turing methods—none of them are mutually exclusive,” Miller said. “You can put and use these together. That is the fun part. In the end, a company has to be good at 3-D modeling because everything rests on the 3-D model.”


April 2017 MODERN CASTING | 25


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60