So as most of you know, I do a lot of machining in acrylic, I have for several years now. Recently the company that I cut 95% of this acrylic for has gone through a growth phase. That’s great on one hand, but as a small shop I have not yet mastered what to do with all the scrap. This is beginning to take up quite a bit of space around the shop. Fortunately this material can be recycled. A few months ago I had a lady to voluntarily pick it up but, my recent calls seem to be falling on deaf ears. I may to look elsewhere for another solution, but in the meantime I had an idea to see if I couldn’t do a little good in the classroom with a few pieces of scrap material.
Recently I was able to tag along as a chaperone on my son’s field trip. While on the trip I asked if the teacher might need any kind of hands on learning widgets that I might be able to help with. I explained the capabilities of the machine and the excess material that I had access to. I also explained that I knew that some of the extra stuff that really goes into the classroom comes out of their pockets most often.
She told me a font and an approximate size so I was set to make some letters. So I proceeded to find the largest scrap pieces that I could find and cut from those. I was able to find (3) 18”x54” pieces of scrap that I could nest the (26) Uppercase letters and numbers 0-9 onto. Since I was going to be cutting relatively small shapes, I used spray adhesive (3M 90 since there was a removable film) in combination with the vacuum table for my hold down method.
I used an Onsrud 66-087 ¼”. http://www.onsrud.com/product/Item/m/search.html?q=66-087. The bit has a coved profile on the side of the bit, this allows the cutter create a radius edge and eliminating the sharp edges that an end mill creates. The feed rate was ~4IPS and 18,000 RPM’s.
Here is the link of them cutting: http://www.youtube.com/watch?v=iL2NVpbbMBE&feature=youtube_gdata
Note: I sent the letters with the blue film still on because I knew that there would be plenty of little helpers eager to peel it off.
Let me know if you have any other ideas for my scrap or have done some interesting work from your own scrap pile.