Hello all. I am new to the forum but have been building and customizing clubs for myself for years. Up until now, all new sets I have assembled have been .370 parallel hosels and I have been able to prep/clean them out with a perfectly sized drill bit (turned it by hand, gently). Recently, I came across a set of brand new Wilson Staff V4 iron heads and I jumped on them being a life long Wilson Staff fan. The hosels are .355 tapered so my drill bit does not fit. For one reason or another, there seems to be a lot of residue left over from manufacturing and I cannot seem to remove it. There is residue on both the walls and base of the hosel. First, I tried cleaning them out with the spiral brushes I use when cleaning out hosels after pulling shafts but this did not do the job. Next, I took a small flathead screwdriver to see if I could chip some of it away. No luck. The shafts will not fit into the hosels at this point so I am at a standstill. Any ideas on how to prep these .355 tapered hosels so I can get going on my winter project? Thank you in advance for your help.
Thank you for the recommendation. I have an old worn out sanding sleeve but it might be time to order more. Didn’t even think of using it since my last one has been worn out for so long now.