Mirror polishing for molds
At Hashimoto Industry, we handle polishing for a wide variety of molds, including precision molds for items such as semi-conductors, items requiring mirror polishing such as electronic equipment, and separable polishing requiring no shining.
We have a crane with a maximum capacity of 2 tons allowing us to handle molds for liquid crystal and plasma televisions.
Hashimoto Industry’s obsessions
Pinhole control
When carrying out mirror surface processes, particular attention needs to be paid to pinholes.
At Hashimoto Industry, we emphasize preparation (grindstone and paper work) in order to minimize pinholes.
“Orange peel” control
If you look closely at the finished mirror surface of a mold you can sometimes see flame-like distortions when reflecting a light in the mirror. This is known as the “orange peel” phenomenon and the phenomenon can occur as a result of marks left during work processes, such as paper processes, or segregation, despite the surface itself being finished to a high standard.
Hashimoto Industry is able to minimize “orange peel”, or even eliminate it completely under the right steel material conditions.
Sample of keyboard mold polishing
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Molds for keyboards need to be of the “superfine” quality ranking because top musicians will notice during performances when there are distortions, even if these are at a level that is impossible to detect by the naked eye. Identifying these tiny distortions is so tough that there are very few testing technicians capable of making these judgments. Even in Japan, there are very few companies capable of producing “superfine” quality. One of these is Hashimoto Industry. (The picture of the mold shows after polishing (on the left) and before polishing (on the right).) |
Sample of audio panel polishing
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This kind of mold, with several angular and protruding buttons, faces a certain problem at the grindstone stage. The problem is that grooves arise in certain locations, similar to the “crossings” of a road. When trying to finish a mirror, it is unacceptable to have even the slightest distortion in the surface. Grindstone work, which ultimately decides the final dimensions of the mold, is an unimaginably delicate process. |
Sample of reflector configuration
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Polishing repeatedly until the processing lines are removed without destroying the shape and carrying out the finishing processes for the perfect shine by hand for each and every process requires unrivaled concentration and determination. Moreover, because the sample is considerably heavy it is not possible to change the direction to make the work easier. The finished mold reflects light like a jewel. (Post-polishing on the left and pre-polishing on the right.) |
Sample of button configuration
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The mobile phone button shapes have undergone electric discharge processing. Once these processing lines have been completely removed, the list of further processes includes application of the grindstone, paper treatment, shine production and the mirror completion processes. Even with a small area, unless the surface is completely flat it cannot be described as a “mirror surface”. Hashimoto Industry excels at this kind of precision work. |
- info@hk-polish.com
3-8-33 Nagayoshi Nagaharanishi, Hirano-ku, Osaka-shi, 547-0015
Please feel free to inquire about polishing or welding for plastic molds. 
