Cutter for 50mm Discs from Sheet Material

prusaprinters

<p>This is a cutter that I've designed to cut 50mm discs from stock sheets of abrasive material. I use the disks to sand my woodturning projects. the cutter can cut other materials too - paper, card, etc.</p><p>The cutter takes two standard "Stanley" type utility / craft knife blades. Since the lower tip of each blade protrudes from the Blade Carrier by 2.5mm, a key safety feature is that the blade carrier cannot be removed from the base assembly without using tools (an Allen key / wrench). the blade is, therefore, never accidentally exposed. The blades can be changed without disassembling the cutter, by simply loosening the two small bolts holding each blade in place.</p><p>PLEASE be very careful when handling blades. I cannot be held responsible!</p><p>The cutter would cut other materials provided that they are no thicker than the 2mm slot height (&amp; a Stanley blade is capable of cutting it!)</p><p>The base has 4 mounting holes that will take M4 hex head bolts to allow the cutter to be mounted securely to another surface. These holes could be drilled out to M5 (if you print as I did, with 4 perimeters).</p><p>As well as filament, you'll also need:</p><p>2 off "Stanley" type blades;</p><p>1 off M5 x 10mm socket button head screw (to secure the Handle to the Blade Carrier);</p><p>2 off M5 x 20mm socket button head screws (to fix together the free ends of the Top &amp; Middle);</p><p>2 off M5 x 30mm socket button head screws (to fix the Top &amp; Middle to the Base);</p><p>4 off M3 x 6mm socket button head screws (to fix the blades to the Blade Carrier).</p><p>Other styles of bolt / screw will also work (I didn't have any M5 x 30mm socket button head bolts at the time if writing, so I substituted M5 x 30mm hex head screws, as in the photos)</p><h3>Print Settings</h3><p><strong>Printer Brand:</strong></p><p>Anycubic</p><p><strong>Printer:&nbsp;</strong></p><p>Kossel</p><p><strong>Rafts:</strong></p><p>No</p><p><strong>Supports:&nbsp;</strong></p><p>No</p><p><strong>Resolution:</strong></p><p>0.2mm</p><p><strong>Infill:&nbsp;</strong></p><p>10% (gyroid)</p><p><strong>Filament:</strong> Ooznest PETG Apple Green &amp; Midnight Black</p><p>&nbsp;</p><p><strong>Notes:</strong></p><p>I printed all parts with 4 perimeters, 4 top layers, and 4 bottom layers. In PrusaSlicer, I added part modifiers to the areas above, below &amp; around the blade fixing holes in the Blade Carrier, and increased the number of perimeters to 6 (a cylindrical modifier at each side).</p><p>The cutter is designed in several parts so that it's possible to print them without supports if they are orientated correctly (The STLs as provided should be the correct way up for printing, but not necessarily the correct way up for assembly!). You may, however, need to add support to the bolt head recess in the centre of the Handle.</p><p>Each part will fit on a 100mm x 100mm build plate, with the tallest part being 65mm high.</p><h3>Post-Printing</h3><p>All the fixing holes will probably need to be eased with appropriately sized drill bits, and several will need to be tapped to the appropriate size, as follows:</p><p>Drill to M5:</p><p>1 x Handle centre hole;</p><p>4 x Top plate corner holes;</p><p>2 x Middle plate fixing holes (at the fixed end with the lug recesses).</p><p>Drill to 4.2mm &amp; tap to M5:</p><p>1 x Blade Carrier fixing hole (the handle fixing hole);</p><p>2 x Base plate fixing holes (through locating lugs);</p><p>2 x Middle plate fixing holes (at the free end).</p><p>Drill to 2.5mm &amp; tap to M3:</p><p>4 x Blade fixing holes (2 in each side of the Blade Carrier)</p><p>To assemble:</p><ol><li>Fasten together the Middle and Top plates at their free ends with the M5 x 20mm screws (the underside of the Middle plate has two lug recesses. The top plate has the narrowest part of the centre hole at the top).</li><li>Fit the top of the Blade Carrier (the end without tabs) up through the bottom of the Middle &amp; Top plate assembly, with the Blade Carrier tabs slotted through the gaps in the Middle plate.</li><li>Align the lugs in the Base plate with the recesses in the Middle plate and fasten together with the M5 x 30mm socket button head screws.</li><li>Fit the Handle to the Blade Carrier and secure with the M5 x 10mm socket button head screw.</li><li>Carefully fit a blade into the recess on each side of the Blade Carrier and secure in place with the M3 x 6mm socket button head screws.</li></ol><p><strong>Cutter side view with parts labelled</strong></p><figure class="image"><img src="https://media.printables.com/media/prints/137788/rich_content/2d7448ba-3fcd-4e04-a9d7-8fe78f16837c/diagram-1.jpg#%7B%22uuid%22%3A%22d6e540ef-d962-4dd2-b130-97de3928c068%22%2C%22w%22%3A699%2C%22h%22%3A570%7D"></figure><p>&nbsp;</p><p><strong>Cutter front view</strong></p><figure class="image"><img src="https://media.printables.com/media/prints/137788/rich_content/f7cae20e-40b2-474a-a563-24da2c142f02/diagram-2.jpg#%7B%22uuid%22%3A%2219fe72b5-0470-4be1-a98e-6afa33f3349d%22%2C%22w%22%3A609%2C%22h%22%3A645%7D"></figure><h3>&nbsp;</h3><h3>Custom Section</h3><p><strong>Instructions for use</strong></p><p>The two diagrams on the Post Printing section should help.</p><ol><li>Using the Handle, gently lift &amp; turn the Blade Carrier (in either direction) to align a Blade Carrier Alignment Line on the Blade Carrier with the Alignment Line on the front of the Top Plate (the open end).</li><li>Lift the Blade Carrier (by the Handle) as high as it will go and turn 1/8th of a turn (in either direction). The cutting blade will be supported clear of the cutting slot in a "park" position.</li><li>From the open end, insert the sheet to be cut into the 2mm slot (abrasive side down) and position against the fixed end. The cutter has Disc Extent Markers on the front and side edges that show the extents of the cut. You can use these to line up your stock material.</li><li>Press down firmly on the front of the top plate to clamp the sheet in place (a finger and thumb on each bolt head).</li><li>Turn the Handle to realign the Blade Carrier Alignment Line on the Blade Carrier with the Alignment Line on the front of the Top Plate, and lower the Blade Carrier onto the sheet. Press down on the handle and turn it clockwise (as indicated by the arrow on the top of the Handle) by one half turn.</li><li>Align the second Blade Carrier Alignment Line with the Alignment line on the Top plate, lift the cutter to the top of its travel &amp; turn 1/8th of a turn to park the cutter.</li><li>Release the pressure on the front of the Top plate &amp; remove the stock sheet and newly cut circle.</li></ol><p>&nbsp;</p><p>Category: Tools</p>