I am new to the machining world and am searching for a little help about reamers. I will try to provide as much information as possible, but if I miss something I apologize. I am running a part on a Robodrill Vertical Mill, out of .188" Vespel SP1. I have 4 holes (that include the origin hole and "skew" hole for inspection) that are a weird size. The print calls out for 1.574mm +0/-.013. I am drilling first with a 1.55mm drill, followed by a .0615" Reamer. My problem is this. When the part is inspected with the 1.55mm holes position is +/- .002mm from nominal (tolerance is +/- .013mm), but after the reamer is ran, I am looking at numbers from 0.020 - 0.030 in both x and y.
My gut is telling me that I am either running the reamer too fast (or slow?) or feeding it as wrong. Currently the reamer is at 4000 RPM, and Feedrate is 1000 mmpm. The part is glued inside a pre-milled pocket in a block of aluminum, with all 4 holes relieved (the reamer does not touch the aluminum). I am not pecking the hole, as it is reaming a total of maybe 15 microns of material. Please help! I cannot get this reamer to run good to save my life!
My gut is telling me that I am either running the reamer too fast (or slow?) or feeding it as wrong. Currently the reamer is at 4000 RPM, and Feedrate is 1000 mmpm. The part is glued inside a pre-milled pocket in a block of aluminum, with all 4 holes relieved (the reamer does not touch the aluminum). I am not pecking the hole, as it is reaming a total of maybe 15 microns of material. Please help! I cannot get this reamer to run good to save my life!