Great Design = Great Results
It is funny how sometimes things just strike you and you start to wonder. This happened to me as I unpacked the Fein KBB 38 core drill sent in for review. As a core drill it is, by design, a heavy tool. It comes packed in a custom designed moulded case. As I took up the case by the carry handle, I noticed that the handle was not in the middle, but about a third of the way along the top. Without thinking too much, I picked up the case and took it to my workshop to begin the review process. I laid the case flat on my worktop and opened the lid. It then occurred to me that the reason why the handle was not in the middle is that the whole case has been balanced around the weight of the machine contained in it. The most obvious response is “Well done Fein, you have designed a case that is brilliant for carrying a heavy machine.” But an additional response is this:- if you can be so particular that you design a case round the machine, then the machine has got to be pretty well designed too, since it is the most important bit. So it was with this thought in mind that I started looking at the drill.
Fein, as the company that invented the first electric drill, has something of a track record in making drilling machines. Nowadays Fein is more commonly known for inventing and developing the MultiMaster range of oscillating tools.
I couldn’t help comparing the Fein KBB 38 to other core drills I have looked at over the last few years. The Fein is bigger and meatier with what seems like a lot of extra features. It may not always be the point to make a core drill too big, bearing in mind that they could be used high up on a steel frame of a building, but the Fein is not too heavy at 14.4 Kgs so is not a problem in trained hands. Handling is also helped considerably by having an optional auxiliary handle that can be attached to the top of the motor housing and another handle above the coolant container. These handles are comfortably in line with each other at the same height, so making for an easy lift in two hands.
Looking closely at the construction of the machine it is possible to see some of the design features that help to make it a high quality tool.
The body is made of solid die cast aluminium in order to keep the weight down. This body is mounted in turn to the machined steel magnet block – probably the heaviest part. The magnet has a holding power of 9000 N so is unlikely to be moved even on the maximum drilling diameter of 38mm. The actual drilling machine is connected to the body via a pair of dovetailed slides, one of which is adjustable to take account of wear and accuracy.
These slides, and hence the core drill, are controlled by the fairly standard three-handled handwheel. The handwheel has to be assembled by screwing in each handle and then, quite unusually, the user can choose to mount the handwheel to the left or right hand side of the machine. This is obviously a great help for users who may have to change the sides depending on how the machine has to be mounted while drilling.
The drilling machine, rated at 1050W, has a sloped upper casing that helps to keep the space taken up to a minimum and aids handling in tight spaces. It is evident that the motor must work hard because it not only has vents at the bottom, but one on the top of the casing as well.
The core bit holder uses a standard Weldon fitting with two grub screws to hold the core drill shank firmly in place. The drive goes through a cast steel ring that is part of the magnet block, so is securely held in place.
The real bit of interest lies above the core bit holder because there are the connections for the gravity fed lubricant unit on the top of the machine. The lubricant is fed through transparent plastic tubes with a body-mounted tap system half way down the machine, so the user can shut off the flow of lubricant when the machine needs to be moved.
The lubricant is fed to the core bit by simply flowing down the core bit holder to where the cutting is taking place.
Looking a bit like a mediaeval knight’s visor, the swarf guard is hinged on one side of the body and is easily swung into place to protect fingers etc from contact and swarf.
What is also quite noticeable, by its complete absence, is any trace of electrical wiring. For protection and safety, this is all concealed inside the body of the machine.
All the switchgear is on the back of the body housing and includes the well protected “on” switch, a prominent “off” switch and the magnet switch. A very robust lashing strap and two nylon strap mounted lugs allow the machine to be tethered safely in place when in the working position.
In a small separate box there are two centering pins, the lashing strap and the hex key for the bitholder. Also included in the kit is a swarf hook.
When it came to testing this drill, I didn’t have a convenient half-built skyscraper frame to work on, but I did have a couple of thick steel joists to drill.
What came over loud and clear using the drill is that it is very well designed to be easy and convenient to use. The motor is quiet and powerful, the dovetailed sliding action is smooth and precise and the lubrication system about as unmessy as these things can be. If I were core drilling for a living the Fein KBB 38 seems to me to be a great choice.
Potential users and dealers should bear in mind that the KBB 38 is part of a range of four core drill units from Fein. The KBB 40 is a compact tool with a capacity of 40mm diameter drills. The KBB 60 has a two speed gearbox and can drill up to 75mm in depth, while the KBB 30 is an ultra compact and lightweight drill used for onsite drilling.