> What do you think of the Klom imitation of it? Initial impressions of the Klom K-747 tubular key cutter
The Klom K-747 cutter is designed to cut Chicago ACE type tubular keys, and the Fort equivalents. It is available in at least four key barrel sizes, 7.0mm, 7.3mm, 7.5mm and 7.8mm. The "common" size seems to be 7.8mm, which is the inside dimension of the key barrel. (In US measurements of such tools given in inches, it seems more common to specify the O.D.) The 7.8mm size is the appropriate one for cutting e.g. DEC XX2247 keys. Comparing the Klom to the drawings and photos of the HPC device in the HPC manual, the Klom has some differences: more labeling than the HPC, less projection of the cutter shaft out the back, and more contact between the cutter knob and the depth knob at the bottom of a cut, a rotating key shaft. In the absence of a Klom manual, the HPC manual is useful in interacting with the Klom version in spite of the differences between the devices. The design concept is straightforward and should be fairly easy to use. The unit comes with a T-style key gauge, but no manual or 2.5mm hex key for making adjustments. The Klom unit provides spring and bearing detents to help hold the key to the proper pin position and the depth knob at the selected setting. With a key inserted for cutting, the device is about 5 inches long, and just under 2 inches in diameter. Overall, construction seems sturdy. The finish is black paint which seems to scratch fairly easily. The Klom design does not allow cutting of left or right offset keys. Both the rotational position knob and the cutter depth arrived in need of adjustment. Both operations are obvious. The rotational adjustment is trivial, since the shaft on which the key mounts for cutting has detents. All one must do is turn the key to the first position, then loosen the set screw in the knob to align the "1" on the knob with the true line. The depth calibration is not as easy, since one must adjust the distance the cutter shaft is slid into the device by loosening the set screw in the knob, pushing it in a whisker, and tightening the set screw. Since the designated difference between cut depths is 0.016", this is fiddly. Chicago ACE numbers pins clockwise from the 1 o'clock position (looking into the lock). Fort numbers pins counterclockwise from the 11 o'clock position. There is also a difference in pin depth numbering between the two manufacturers. The Klom unit matches the Chicago scheme. The HPC manual describes these numbering schemes, and the information there applies to the Klom as well. You will need to understand these differences, as well as which variant was used to specify the bitting you will use, to cut a usable key. Both brands have some numbering painted on their knobs. It seems that it would quite easy to paint full rotation and depth numbering for both Chicago and Fort schemes on them, which would make using the devices easier for novices, but neither does this. There is a little bit of play in several places that could affect accuracy: the depth knob rotates a large screw whose threads could be tighter; the end cap that holds the key on the shaft can wobble enough to shift the key side to side a wee bit. The cutter shaft also has more play than is probably necessary, but that won't affect depth. Since this is a low-cost Chinese device one would expect a few issues, and this device does present a few: * Both sets of detents were a bit grouchy at first, as if there was a bit of manufacturing debris inside, but seemed to settle down some after a few minutes use. * I managed to accidentally rotate the depth adjustment a couple of times while making a cut. The knob that turns the cutter meets the depth adjustment knob at the bottom of the cut, and depending on how hard you're pressing, friction between the two may be enough to cause the problem. Murphy is (as always) on hand to ensure that when the knob moves, it goes toward a deeper setting, spoiling the key. This is a design issue that will have to be worked around by paying careful attention during use. It would be nice if the depth could be locked. There are set screws to adjust the spring tension on the detents, and I tightened them a little. This helped some, but not enough. * In my first attempts, I had some small variations in depth of cut between different pins that were supposed to have the same value. The above notes on play probably explain this. Practice will help. I haven't tested enough yet to opine on the impact in terms of marginal or bad keys. * It would be nice if the key gauge was labeled on both sides, since when holding it in one hand and the key in the other, one uses it face up for odd cut sizes and face down for evens. (You could also turn the key around, but it's easier to keep track of where you are if you flip the gauge.) I find the T-style gauge easier to use for fine evaluation of depth, and the Southord style (key-shaped) gauge faster for reading bittings from unknown keys. I was unable to find the Klom cutter for sale in the US, and had to order from China. I ended up using dhgate.com. Delivery time was nearly a month. Listings also appear on aliexpress. De
