|Filename||File Type||File Size|
|HDM Slat - V3||c2d||128.00kB|
|HDM Slat - V3||c2d||128.00kB|
This file ultimately creates and/or modifies slats for the HDM hybrid table. It was created using CC version 724, so you’ll need to be using a compatible version and ideally that one or later. You can either use your original slats or modify them, or you can create new ones from a slightly oversized blank. You certainly could use this to simply replicate the original slats, but I went one step further and created what I think is an improved version. If you use all the available options, it will create slats that have holes for an array of 28 M6 threaded inserts spaced 50mm apart and 8 ¾” dog holes spaced 100mm apart or 50mm for the first and last dog holes. A standard MFT table uses 96mm spacing and might use 20mm dog holes instead of ¾”, so you will need to modify this spacing and/or sizes if you want to use accessories that require it. If you do all 8 slats this way, you’d have an array of 224 threaded inserts and 64 dog holes. I used an impact driver to install the M6 threaded inserts which worked well and made short work of it.
The idea behind this is you’ll spend a bit of time and resources making the slats, so you probably won’t want to cut into them. Use a wasteboard on top of the slats with through holes cut with a matching array if you need to cut below your material. If you use ½” material for the slats and wasteboard, you will only give up ¼”of Z height compared to the original ¾”slats.
You can’t completely machine a slat horizontally or vertically on the HDM as the slats are 701mm long and exceed the HDM’s X and Y axis. However you do have enough by machining them diagonally and that’s what this file does.
You are also certainly not limited to MDF. Although I have yet to dry it, phenolics or HDPE would be other options which might work better for those folks who want to use various coolants which don’t play well with MDF.
This file uses layers which you can turn on or off depending on what you want to look at. The toolpath groups are not intended to use all at once as you’ll need intervention along the way which I’ll explain. I’ll try to list all the materials you’ll need along the way.
Step 1: Edit the CC file to match your source material height and whatever cutters you’ll be using along with the feeds/speeds appropriate to your cutters and material. I used an equivalent #102 1/8” downcut and an equivalent #201 ¼” downcut for most of the work along with an Amana RC-2250 for the surfacing operation. The surfacing step is optional and you probably won’t have a RC-2250, so just adjust this toolpath as needed or skip that step if you don’t care about being perfectly level. You can always adjust your depth settings to cut deeper into the base to compensate for any imperfections in your base. Enable the first toolpath group ONLY labeled “Mounting Holes For Base” and save the file, then load it into CM.
Step 2: Cut a piece of MDF for your base. I recommend using ¾” MDF. You can use other thicknesses, but you’ll need to use different length threaded inserts than those specified. I’m using a piece that is 721x200mm which is the minimum size you’ll need. You could certainly use a base that is as large as your table and cut it to size later. If you use the minimum size, placement of the base on the table is important as you’ll need to be within a few mm of the final location. You can turn on the layers which show the hybrid table and use that to place the bottom and right corner at the correct location. A good size to use would be 821x300mm which will make initial placement less critical. Once you place the base, temporarily secure it to the table using whatever workholding method you want. Once the 5 initial holes are made, you won’t need the workholding for the base anymore as you’ll be screwing it down to the table.
Step 3: Jog the machine as far to the left and towards you as you can get it and then zero the X and Y at this point. You should not have to change those zero points again for any of the following steps. You will need to adjust the zero on your Z for each toolpath group and tool change so do this now after installing the 1/8” endmill and run the first operation which will cut 5 holes for mounting the base to your table. Remove the workholding.
Step 4: Remove the 5 M6 hex bolts from the slats in your table which align with the 5 holes you just created in your base. You’ll need (5) 40mm M6 hex head bolts to replace the original ones as they aren’t long enough for this purpose. Once tightened the base will not move for the remainder of the operation, but as previously mentioned keep the original X and Y zero points as these will not change at any time.
Step 5: This step is optional, but at least the first part is recommended. Edit the CC file, disable the first toolpath group and enable the “Drilling Alignment Holes” toolpath ONLY under the “Optional Group for making alignment holes and surfacing”. These alignment holes can be used if you want to remove the base and place it exactly where you had it before as you might be 1mm or so off if you just use the mounting bolts. The alignment hole on the left should match up the jog/rapid center point on your machine, but regardless it will match the coordinates in the CC file. You can job your machine to those coordinates and align the base to your spindle using a piece of ¼” drill rod (like the one that comes with the BitZero). The other alignment hole is exactly 200mm to the right and 150mm back from the center alignment hole. You can jog the machine back and forth between those two points and tighten the base down once they both align. The second and third toolpaths of this toolpath group is for surfacing and must be edited as necessary if you want to use it.
Step 6: This step provisions the base for mounting your slat blanks. It creates holes for threaded inserts and a slot to accept a piece of t-track to use as reference. I’m using a piece of t-track that is 19mm wide, 500mm long and has holes that are 4” on center. You can certainly use a piece of wood or other material that is straight and about the same length by editing the slot that uses it. The holes are for 6-32 threaded inserts, but you can use your own method for securing the straight edge of your choosing to the base. Enable the “Create Provisions for Holding Slat” group ONLY in the CC file and run this with a 1/8” endmill after zeroing the Z. It will create holes for the 4 M6x15mm inserts used to hold the slat blank and 3 more M6x15mm inserts for temporary workholding of the slat blank until the 4 mounting holes are created.
Step 7: Install (7) M6x15mm inserts. The four for slat mounting must be countersunk 2mm as you’ll be punching holes in your slat blanks directly above them. Install the threaded inserts for the t-track and the t-track or whatever other straight edge you are using. The length isn’t important, but it must be less than the 701mm length of the slat. 500mm works well. After this step the base is complete and can be used indefinitely to make new slats.
Step 8: At this point you’ll want to change the CC file material thickness to match the material you are making or modifying your slats from and install a ¼” endmill. You’ll need to set Z zero for the slat this time, but as with all the other steps the X and Y zero will remain the same.
If you are only modifying your existing slats you can just secure them to the base with (4) M6x20mm hex head bolts. Otherwise you’ll need to secure a slat blank to the base using some type of workholding in order to machine the 4 mounting holes with the “Temporarily Secure Slat Blank to Base” toolpath group. After this step you can bolt your slat blank to the base and you won’t need the workholding. The size of the blank needs to be slightly larger than the finished slat. I recommend cutting the first slat larger than the rest and enabling the tabs. After the first one you’ll have a cut-through reference on your base for the slat and you can cut your slat blanks to about 77x704mm. The ¼” endmill will remove all the extra material and you won’t need tabs. With the slat blank mounted you can run the final three toolpaths ONLY. Screw in your M6x15mm inserts and you’re done.