MCKECHNIE INTERNATIONAL

DEBURRING MACHINE

MODEL 131-EC

Deburrs outside straight edges of parts produced on a CNC punching machine.

Three problems arise from cnc nibbling with a parting tool:

• Burr on the bottom side
• Pips, nibs, and microjoints on the middle edge, and
• Tool deformation marks on the top side.

Notice that the chamfers are not sanded off, they are cut off. You don't drill a hole in sheet metal, instead you punch it. You don't saw sheet metal, you shear it. Why should you waste money on many many sanding belts to remove burr and tool deformation?


This is the starting position for a sheet to be deburred. From here the operator will keep a slight pressure towards the back gauge (similar to a guillotine shear) and then slide the material to his left, until the powered rolls pull it through the cutting blades. 










This photo shows the operator preparing to run a sheet of stainless steel through the patented 131-E sheet edge deburring machine.

CNC punching machines leave 3 problems:

1. Nibs, pips, and microjoints on the 90-degree sheet outside edge, causing mis-gauging on the press brake.
2. Dangerous burr on the bottom.
3. Unsightly tool deformation marks on the top of the sheet edge.

The 131-E solves all 3 of these problems in one pass, at 20 meters per minute, even on stainless steel.



Notice the outboard support with lockable clamps. This support can be slid out nearly 750 mm away from the cutting tools, and could then support a sheet up to 1.5 meters wide. When not needed, the support can be swiveled down to a lower position. The red and yellow electrical switch on the back corner of the machine comes only with the "EC" designated machines for CE requirement countries, and requires manual resetting after a zero voltage.

From this view you can see the 2 separate switches for the main motor and for the sanding belt motor. You can also see in the lower cream-colored portion the hand opening for removal of the swarf cover. Lockable wheels are at the bottom of the machine. To the right of the blue area you can see the adjustable outboard support. Electrical power is single phase, 230 volts, 50 Hertz. Exclusive exporter is McKechnie International, 104 Hickory Tree Road, Longwood FL 32750 USA. Phone 001-407-332-8340. Fax 001-407-260-2569. Email: budmckechnie@yahoo.com.

Model 131-E three stage sheet edge deburring machine, thickness capacity from 0.7mm up to 6mm thick. Speed 20 meters per minute. Very good for deburring all materials, but especially Stainless Steel. Ten times faster than manual methods, and ten times better appearance of deburred edges. Even the nibs, pips and microjoints are quickly and completely removed. Return on investment is usually 68% to 100% annually, sometimes even better.








The two knobs at the top of the machine are to change metal thickness. Normally it's not necessary to change unless the sheet thickness varies by over one half millimeter. Operator need not know the thickness to adjust for it; he merely sets the knob so the rollers grip the material. After just a little experience, this takes about 30 seconds.

We swung the hinged safety guard up and back to show you the 3 stages in the edge deburring process. From the far right, an opening in the back gauge permits the sanding belt to remove pips from the 90-degree edge. Next, to the left you see the 2 blue safety covers covering the 2 upper hardened and ground powered pinch rolls which grip and pull the sheet through the machine and past the two knives which cut the chamfers, one lower and one upper chamfer. Deburring with this machine will not change the programmed part dimensions.

Removal of the first stage head reveals the 6-corner tribit used to cut the first or lower chamfer into the material, thus forever completely and eternally removing the dangerous burr. The chamfer is the same exact size from the beginning to the end of the sheet, and also from the first until the last sheet of the job, unless the operator readjusts the blade. Final users of the customer's product are very pleased with this consistent machined edge, infinitely better than that derived from manual filing or scraping, which looks crude and irregular, and doesn't even remove the nibs!

On the far upper right you can see the knob for adjusting the 40 mm. wide sanding belt mandrel up or down to expose a new level of sanding belt when necessary, usually once per day and only a few millimeters, depending upon metal thickness. Note that no dimensions change and very little dust is generated, since only the tiny nibs or pips and occasional microjoints are being removed. The programmed dimensions remain exactly the same. Purpose for nib removal is A. Better appearance, and B. More accurate gauging to the edge when put into a press brake. Replacement sanding belts are available locally at a few Euros each. Ten spare belts come with the machine.




Here you see the two hardened and ground lower rollers, and to the right the triangular blade with 6 cutting edges. Each cutting edge can last from 2 to 4 days. After all 6 cutting edges have been used, you can grind about 1/3 to 1/2 mm. from each end to produce 6 more good cutting edges. With 30 mm of grinding stock, you have about 250 cutting edges in each blade, for a blade life of 7 months to perhaps two years or more. When the first stage blade becomes too short, you can grind a special angle on its end and use it in the second stage cutting station. This is why the total tool cost for operating this machine is only about the price of one cup of coffee per week.









First stage cutting station, removed from the machine for clarity. Triple sided blade is shown at the top. Entire arm pivots about the pin on the left, controlled by the brass chamfer adjusting screw at the right. Adjustments are usually made only when material thickness varies by more than 1/2 mm.

Each of the six cutting edges of the first stage blade can last 2 to 4 days. Thus the 6 cutting edges last for about 2 weeks. At that point a simple square 1/4 to 1/2 mm grind from each end produces another 2 weeks of blade life. With 30 mm of extra length, the total blade life is 7 months to two years or more. Total tooling cost is therefore only about 45 cents (= a half Euro) per day. Note the large husky gears, mostly steel but every other one is long wearing phenolic to keep the machine working quietly. All the gears will last at least ten years, and will go 15 years or more if the operator puts a dab of grease on one tooth once per month. Machine maintenance is virtually zero. 

The brass bed minimizes scratching the sheet. Just to the right of the cutting tribit you can see a small brass horizontal adjusting screw for increasing or decreasing the length of the tiny edge chamfer. A quarter turn will change it enough to cut one mm thicker (or thinner) material. The only 3 adjustments for the cutting zone are A. For metal thickness with the 2 overhead knobs, B. for chamfer size, as indicated above, and C. Rotating or replacing the blades. It's just as simple as ABC! 

Check out the bearings on the roller shafts. You'll see NO oil cups. That's because these bronze bearings are graphite impregnated and self lubricated. Nothing could be simpler. In any one day, one McKechnie deburrer can process more material than most cnc press brakes, and can keep up with up to 3 cnc punching machines. Total estimated tooling cost is only about two or 3 euros per week, or less. 

This shows the second head removed and turned upside down, with the 2nd stage triangular blade in place.

Second stage head removed, to show the blade adjacent to the upper roller, and also the brass adjusting screw for quickly changing chamfer size. 

 Second stage upper head removed and inverted to show second stage blade, upper roller, and small brass screw for quickly adjusting upper chamfer size. Total thickness adjustment time for entire machine averages less than one minute.

To change the dull blade after 2 to 4 days' use, merely loosen the two screws above the blade and slide it out. Be sure to place the sharpened blade in the same exact location and position. It's very simple and takes only less than a minute.

This second stage grinding attachment comes with every machine. 

The knob at the top of the photo is for adjusting the height of the sanding belt. You can see that the lower half of the belt has already become worn. Adjustment is only the thickness of the material being sanded. Belt width is 1-1/2 inches or about 40mm. On 1mm thick material, you will have 40 different positions. Belt diameter is 6 inches. You can change belts in less than a minute. Usually a belt will last about one month. Replacement belts are usually available locally at a small cost, probably less than one or two euros.

 The 131-E come in two plywood boxes, to minimize shipping costs and prevent damage. 

Sheet metal base (painted cream color) is in the front box; machine working parts (blue) are in the rear box.

Sheet metal parts are positioned on the floor. 

Sheet metal base is quickly assembled, using only a screwdriver.

Caster wheels are added. 

Top is lifted on by two men or a forklift. Total assembly time = 26 minutes.