REVIEW ON THE
ENCO 5"X 12" COMPACT MACHINING CROSS SLIDE
I recently and with much trepidation on my part, purchased an Enco brand machining slide which I hoped to use in conjunction with my drill press. It appeared to be as many other clones of slides being manufactured in the orient. I had hoped to be able to afford one of the better table slides as even the most " affordable " milling machine is a bit beyond my present budget and I needed reasonable milling capabilities now. Not a year from now. Though the drill press is not generally used as a milling machine. I had no choice put to resort the this poor man's milling substitute.
Earlier in my model making career, I was adapting the lathe for all my milling requirements but found it to be a bit inconvenient to use.
I saw the advertisement for this machining slide in a resent Enco sales flyer, though it had not been the first time as I had seen machining slides in many other catalogs. I had also been very leery about using one of these Asian units that "looked" like the real thing but obviously were not. For several month I had adapted one of the many clones of the cross vice type of attachment sold for drill presses. It worked to an extent but it was a bit hard to use and read the calibrations of the dial. The dial had been calibrated to read .125" per full revolution due to the fact that it had a coarse 8 thread per inch lead screw. The dial was also very small permitting only 25 marks separated by only about 1/16". All in all it served its purpose for the time I had it.
When I received the flyer containing the slide of the compact machining slide and its description, I thought it was to good to be true but I went ahead and ordered it. I had been accustomed to about a two week wait period on most orders but I was extremely pleased to have received the unit in only 4 days. So far so good.
When I opened the box and saw the unit I thought someone in the shipping department had make an error. This thing was beautiful! Once I wiped away the layer of generic packing grease and got a closer look at the unit, I had to admit that I still didn't believe it could be that good. Sure, it looked good but...... The top table surface measures just over 5" x 12" and has two 5/8" wide slots taking 1-1/16" wide "T" nuts. The ground surface is as flat as I am able to measure with my Starret square. The slide advance knobs are of good quality and appeared to be very well machined. The graduated dials are nicely engraved with 100 marks and can be re-zeroed after initial settings have been achieved. Another extremely important use of re-zeroing a dial after the initial measurement has been obtained is to use it as means to make repetitive cuts such as a deep blind slot running a certain length. Since you will have to make multiple passes as you gradually deepen the slot, you can set your dial so it reads ZERO at the end of your slot. By carefully advancing until the dial reads zero, you can insure that you will not over run the slot. The sides themselves are fully dovetailed and have 5" long jibs. adjustable with four locking set screws per jib. After some minor adjustments to the jibs and installation of the knob handles, I went ahead and mounted the unit directly to my drill press base. You would have normally mounted it on the table but I have one of those small 8" capacity bench top machines so I opted to mount it on the base. This had the benefit of being a much more rigid mount and providing sufficient vertical clearance for most work. The next thing to do was to check the accuracy of the readings on the dials so I simply clamped a small "V" block I happened to have to the center of the table squaring it as well as I could by eye. I chucked a .030" capacity test dial indicator to the drill press and brought the stylus to bear against the front center edge of the block. I advanced the cross ( Y feed ) toward the indicator so I began to get a movement on the dial needle. I began to compare the slide's readings with those of the indicator. After advancing the cross slide for a full .030", I looked at the dial indicator and it also read .030". I was shocked at this time so I proceeded to check the longitudinal advance an got the same results. I was not able to check the whole range of the X & Y advance but I figure and hope that any amount of accumulative error will be minimal. I also checked the squareness of the spindle to the horizontal surface of the slide table. I have a 4" diameter faceplate with a 1/2" shank that has a very true running front face in relationship to the axis of the shank since it was turned from a single piece of stock, so I used that to check the axial alignment of the heads to the table. After chucking the face plate to the drill press spindle I lowered the quill so it touched the surface of the table as I adjusted the drill head so the face plate bore flat on the table surface. This got me within a thousands of an inch or less. Now I was ready to mount a machining vise and square the non moving jaw to the longitudinal advance. Of course, you could clamp any other type of device such as collet fixtures, rotary tables, chucks, or simply use "T" nuts, studs and clamp straps to hold normal or irregularly shaped work down. I first checked the vice jaws to make sure they were vertical and as it turned out, I had to shim them to 90 degrees. I set up the test dial indicator once again and used it to bring the non moving jaw to less than .0005" with the "X" advance along the total length of the jaw. I gradually tightened the vice to the table's "T" slots while checking the alignment every time. It was still perfect so after clamping a rough cut chunk of aluminum to it, I began to take some test cuts with a fly cutter and end mill. The cuts were much more smoother than those with the previous setup using the drill press cross vice as a machining slide. I had not been getting good side cuts with the end mills as well as irregular surfaces with fly cutters, but that was no longer a problem. I assume, I was getting some vibration on my old unit as well as the fact that the lead screws had some play, allowing the vice to vibrate or move slightly during some cuts. No more movement with the new unit. Even attempting to force it by hand proved to be futile. The true test came when I turned this rough chuck of stock to a beautifully machined rectangle with all of its surfaces flat and square to each other to the satisfaction of my Starret square.
The result of this purchase has given me the ability and the capability of performing milling and other specialized cuts that I couldn't previously do with equipment presently in my shop. The best part of this story is the price I paid for the slide, $74. ( on sale ) plus shipping.