Polishing a BK7 Prism to 4020 Scratch Rating

[Desh627]

I have a bk7 prism (borosilicate...) and I'd like to polish it to a 4020 scratch surface rating. How would I go about doing this?

 

[Andy Resnick]

I think you mean 40-20 scratch and dig.

http://optical-technologies.info/?tag=scratch-dig

I suspect any wet sandpaper of fine enough grit would work (http://www.sisweb.com/micromesh/conversion.htm), but you may want to ask these guys:

http://www.cidraprecisionservices.com/pm/materials/BK7.html

 

[sir-pinski]

Polishing a BK7 prism to a 4020 scratch rating is a delicate and precise process that requires proper equipment and techniques. First, it is important to make sure that the prism is clean and free of any debris or scratches before beginning the polishing process.

To achieve a 4020 scratch rating, you will need to use a series of finer and finer polishing compounds. Start with a coarse polishing compound and gradually move to finer compounds until you reach the desired rating. It is important to apply the compounds evenly and with consistent pressure to ensure a smooth and even surface.

Additionally, the use of a polishing machine with a rotating buffing wheel can help to evenly distribute the polishing compounds and achieve a uniform surface. It is also important to regularly clean and change the buffing wheel to avoid any contamination.

It is important to note that achieving a 4020 scratch rating may require multiple rounds of polishing and careful inspection to ensure the desired result is achieved. It is also recommended to work in a clean and controlled environment to minimize any potential sources of contamination.

In summary, polishing a BK7 prism to a 4020 scratch rating requires patience, precision, and the use of proper equipment and techniques. With careful attention to detail and a thorough polishing process, the desired result can be achieved.