Review on Bosch PCM12 Quick Change Mandrel by Jeff Payne

Bosch now offers you the opportunity to adapt your old hole saw to the Power Change system. allows for quick hole saw changes without loosening the crown, removing the mandrel that has become wedged on the hole saw due to the torque of the drill bit, and installing the new hole saw on the mandrel and securing. When installing a lock, if you need to avoid cutting holes of different sizes, such as B. Holes for faucets and drainpipes or two holes in a door, you will appreciate the use of this accessory. There are a few items in the Power Change product line that can be confusing, so use caution when adding items to your cart: Mandrel Only: - PCM12 1/2" Mandrel - PCM38 3/8" Mandrel - PCMSDSPL mandrel with SDS-Plus shank kits: - PCM12AN 1/2" mount with two adapter nuts (small, large with locking pins) - PCM38AN 3/8" mount with two adapter nuts (small, large with locking pins) - HE1 comes with a 3/8 "arbor" with adapter nut for larger holes Adapter Nut Sets:- CK1 6 Adapter Nut Set: 2 small and 4 large adapter nuts for small to medium hole saws - CK2 6 Adapter Nut Set: 2 small and 4 large with locking pins for small and large hole saws - AN01 set of 2 pcs. Small Interchangeable Nuts (9/16" - 1 3/16") - AN02 2 packs Large Interchangeable Nuts with Locking Pins (1 1/4" - 6") Still confused? tarted probably buy HE1 and CK2 kits. This gives you a 3/8" mandrel, hole saw adapter, and the ability to enlarge undercut holes. I'm really not sure what the benefit of a 1/2" arbor is, other than the fact that most hole saw arbors are 1/2" and are probably designed to cut 6" diameter holes. A 3/8 inch mandrel seems to fit me perfectly. Pros: - Affordable price - Ability to swap out hole saws in seconds - Easy to install adapter nuts. Cons: - Runout creates wobble that wasn't there in your case before (depth and stowage issues) - No spring/pull mechanism (who does?) As you would expect from a quick change system, runout can be an issue with some adapter nuts are better made than others and you will find that you can reduce or eliminate runout by turning the shift nut to one of the other 5 possible hex positions in the shaft. Sometimes it works, sometimes it doesn't. Either way, this partially defeats the purpose of a quick switch. The system wastes your time which is why I gave the product 4 stars out of 5. Make sure the tops of your bits are flat so as not to aggravate runout (something Bosch seems to have accounted for by sawing their own holes). Another thing I noticed about Bosch hole saws with gear adapter nuts, one of the three nuts (small, large, large with locking pin), Bosch always uses a nut without pins and includes a washer. This is obviously a cost-saving measure, but I'm wondering if adding a thin shim reduces the chance of runout. What I don't understand about the CK2 kit is that the washers that come with the small adapter nuts are too big to fit properly. Kit CK1, which includes 4 large nuts with no locking pins, does not include washers at all. Somebody didn't think these kits through properly. I would include small washers with small nuts and large washers with large nuts, adding more threads to the nuts to compensate for the washer thickness. If you don't have a set of bits with these adapters I would recommend buying a full Bosch set that will fit rather than picking your favorite brand of bits and trying to adapt them to this quick change system.