Yesterday I sand cast my third kitchen cupboard handle. The strange part about sand casting is the pour. I find that quite often when I think pouring the metal has worked, it hasn’t and vice-versa. This time I thought it hadn’t worked, but when I took the mold apart I found that a small bit of sand had fallen from the sides into the bottom of the mold. This resulted in the handle having a large dint of missing metal in the back. Although this wouldn’t be seen I have decided to recast this to make one more perfect. I will be melting the metal to reuse for the next one.
Yesterday I cast another cupboard door handle. I have six to cast in total. They are all similar to each other however some are twisted more than others. When I poured the cast I thought it hadn’t worked properly. It wasn’t until I opened up the mold that I was happily surprised. I spent the afternoon cleaning up the piece with my files. I have four more to cast and then I will solder on threads to the back of then so as they can be used for the cupboard doors.
Over the last few months I have been thinking a lot about the tools that I need and the ways in which I can innovatively use the 3D printing process whilst not spending more money than I would to just buy a tool. I have gone through quite a few different ideas and developed my tooling to where I feel happy to now start testing prototypes.
The mallet handle progressed from just directly 3D printing a mallet to breaking it down and looking at each part. The first idea, was to CNC mill a multifunctional handle which could be used by screwing on and off mallet heads which could be printed or milled from different materials such as wood or hard resin.
I designed a handle which had a nice form and would have looked great in wood. Before the chance came to mill this I had developed the idea further, which I was glad for. I decided that I could go even further with the design of the tool and develop it specifically for my own use. I took clay imprints of my handprints as I would be holding certain tools. I then 3D scanned these to develop into handles for my tools.
I have also been developing various hammers in CAD and testing the cost of them to 3D print against the cost to buy from reputable jewellery suppliers. The average cost of a jewellers hammer is around £15-£30 depending on the use. There are some more expensive hammers around £60-£80 with changeable heads.
I kept developing and changing my hammer to make it affordable to print. I managed to get the cost down to £24.02 to be printed in steel. One advantage to 3D printing this was that I was able to customise the hammer head with my hallmark. I will make a separate handle for this hammer to the mallet as it is much smaller. I may either carve one in wood using my 3D printed chisel or CNC mill another handle with my handprint engrained.
Last week I cast one of the door handles I 3D printed a few weeks ago. I decided to use bronze as the melting temperature is less than brass and it is less toxic to cast. I may still cast them in brass in the future.
At first I tried melting the bronze using two torches. I wasn’t able to get a high enough temperature to make the metal liquid enough. I then moved on to using the electric crucible which melted the metal with ease. The first pour I made a mold of the door handle and a smaller version that I may use as jewellery.
After taking apart the larger mold I found that the pour hadn’t worked. I think this was either down to the fact I pored with a hesitation or maybe the mold was too big. It was still in tact enough to try again. The second pour went well. I sat the mold at a slight angle for the pour and also added air holes in to the mold.
I have started to clean up the handle. I have cut off the sprue and started to file some areas. I might leave some triangles textured and some polished. I plan to add a threaded post so I can fit it to the cupboards.
Today I 3D printed some handle ideas I made in CAD a few days ago. They are designed around they way honey is found in cliffs in the wild. I was thinking that it would be good to have slightly different handles on each cupboard so as they are all unique and will also emanate the differences in form and shape in the wild.
I decided I wanted to smooth down the 3D prints before casting to see if the final sand casts would also be smoother. I placed the prints into a container with acetone in and a covered lid. I drilled small holes in the prints so I could stand them on a nail in the box elevated above the acetone. When I checked them after an hour there was little change to the prints. I added a little more acetone and left them for another hour. I noticed that some areas had smoothed out and others hadn’t. I tried balancing them on their side in the container and left them for another hour. When I got back some areas had smoothed out too much and other areas still hadn’t.
The smaller of the two prints was very melted and bendy at the end. I think I will reprint them and try using the acetone on a hot plate. I have watched video’s on this and it seems to only take ten minutes at the correct temperature. I think this may have a better effect in smoothing down the entire object.