Bosch 85078 Speed Carbide Tipped Keyhole Review

Of course it is not carbide bit as advertised. I received mine today and as others have mentioned it is an HSS or HSS bit. This is false advertising.

requires practice to cut straight and remove from slot when complete. It's also a little tricky to figure out what depth you want to go to. A very sharp sleek cut, while a bit cool it does take some practice to get started.

It doesn't look like a real carbide drill, only HSS which disappointed me. When I plug it into the router, it cuts very well. I'm really very impressed with the haircut, I wonder how long it will last. If it lasts I'll buy more.

I use this attachment on my CNC machine to make keyholes in shadow boxes. I created a file that creates two perfect keyholes 16" from center as it is intended to be hung on rivets. This can also be done with a manual milling machine, eliminating the need for a CNC machine.

Like many other reviews, this is NOT a carbide tip, but an HSS tip. The Bosch model number is correct, so the Revain description is incorrect. So far I've had good luck with the Bosch so I'll keep it and see how long it lasts. I am disappointed that I could probably get a carbide tipped bit for a similar price. I'm only deducting 3 stars because of the inaccurate product description.

My only issue is the description which says it is a carbide tipped cutter when in fact it is an HSS cutter without carbide tips. It was a good value even for an HSS bit and no matter how much I use it it should be fine. Just note that the tip is not made of carbide. I had read other reviews talking about the same issue so I was aware of the possibility. I like Bosch cutters, but I don't like inaccurate product descriptions.

Excellent purchase, very satisfied! This little thing is very sharp and cuts through 12 pieces of hard elm wood with ease, which is why I'm selling it as floating shelves. It has retained its new sharpness so far after these 24 uses, as well as the 5-8 or so practice runs I've used it on pine for. I'll buy another one once this one dies out (which ALL routing bits eventually do). I'm assuming a very good service life and I'm happy to give this little cutter 5 stars. this is for keyhole hanger…

I'm an experienced hobby carpenter but this was my first time trying to make a keyhole with this tool. First, for those thinking of using this router bit on a hand drill, it won't work well because you can't control the initial plunge action and most drill bits aren't fast enough for side cuts. This bit is designed for high speed. I used it in my table router and attached two wood stops to the tabletop to make two identical keyholes on a pair of Brazilian cherry boards. I am very happy with the