- October 2, 2016 at 12:08 am #18848
My problem/issue right now is building the table to put my MPCNC. (well other issue is spindle, but will post in separate section).
I have completed the print of all the parts, assembled all the bearings/bolts and put it all together. (see attached).
I have the 25mm (OD) tubing (from bunnings) (see attached) and all the feet/corner/etc fit.
I have cut the Z length (not shown) and legs (see attached) using a 3D printed dremel cutting attachment. This actually worked great each leg come out 138mm exactly.
My problem right now is I am trying to build the underneath of the table and I cant seem to get my 2×4 (well 45mm x 90mm) lengths square, so I can drill/put in the 125mm wood screws to join them in a quick/dirty but joint. I think plan to screw down a pre-cut sheet of MDF (16mm) as the first layer of my table.
Any suggestions on how to keep them square as I drill/screw?
Attachments:October 2, 2016 at 5:47 am #18859
Pick yourself up one of these. Then clamp your pieces to it while you screw them together. Keeps the pieces of wood square and frees up your hands. Then just move it to the next joint. Your table doesn’t have to be dead square as long as it’s slightly bigger than your router. You can just attach one foot, then square up the rest of it.October 2, 2016 at 8:57 am #18865
the 3d printed cutting attachment looks awesome, do you have a link to it?October 2, 2016 at 11:35 pm #18897
The Thing is the Rod saw, with Rotary Tool Flex dremel 225.
I have attached some other shots of it as I used it.
The holders for the tubes (25mm OD) I just whipped up in OpenSCAD.
Here is the source for it if you want it as well.
——— Start ————
$fn = 60;
tube_r = (25.5) /2; //the .5 is slop
thickness = 7.5;
outer_r = tube_r + thickness;
top_gap = 2;
bottom_from_base = 15;
screw_hole_r = 3/2;
counter_sink = 2.5;
counter_sink_r = 6.2 /2;
translate ([0,0,outer_r – thickness + bottom_from_base])
cube([outer_length,outer_r*2,outer_r – thickness + bottom_from_base]);
cube([mounterX, mounterY, mounterZ]);
translate ([-outer_length/2,0,outer_r – thickness + bottom_from_base])
translate([-outer_length/2,-top_gap/2,bottom_from_base + tube_r + thickness ])
translate([((mounterX – outer_length )/2) + outer_length,0,-mounterZ + 0.01])
cylinder(d=screw_hole_r*2, h=mounterZ * 2);
translate([0,0,mounterZ +counter_sink ])
cylinder(h= counter_sink, r2 = counter_sink_r, r1 = screw_hole_r);
——— end ————
Attachments:October 28, 2016 at 10:25 pm #20217
I have still been working on it, to busy to post/updates.
Anyway. I have the base/table completed complete with raised runner/mounting sections on the side, and a place for the stock sized MDF spoil board to slide up and one (locking it in is still to be done, I have a plan).
Attachments:October 28, 2016 at 10:28 pm #20222
still more pictures. this with the runners.
Plan for the frame to go on tomorrow, square it, and then screw and lock it down.
Attachments:October 29, 2016 at 2:59 pm #20245
Looks good, like the way you have incorporated the spoil board. What’s your plan for clamping?October 29, 2016 at 11:02 pm #20268
put the legs down today. Measured many, screwed once. And ended up not being screwed -> Diagonal was less than 2mm difference. (1.2mm). So over 1.4 meter diagonal I think that is acceptable.
Aha!. spoil board clamping. Well Since the spoil board is 1200x600mm and thus have underlap (under the rails at either end) I am going to drill 2 holes (one each end) 8mm or 10mm (not decided yet) through the spoilboard and board underneath, and use a bolt up from below and wing nut at top (easier to lock down).
Underneath the bolt will be coming up via/through left over bit of 2×4 and recessed in the wood (thus making the wood the securing method). Since the wood is just long enough to fit, it uses the bracing wood not to turn.
Step 2 is future planning – I then take the bolt/wood out, slide the spoil board 1/2 off the edge, and secure the bolt to the board. Slide it back into the table, until the board/bolt is butted hard up against the end. then I drill through the existing hole (now some where in the middle of the table) to make a hole. Repeat the other way.
This Hole I can now re-create via the CNC/drill the next time I have to make a spoil board and have it all exactly lined up.
Still researching what method to secure clamps to the spoil board. possible T-bit via router. or recessed hole/lock nuts. Still reviewing methods and available tools.
Attachments:November 6, 2016 at 1:12 am #20637
Okay good news (and some annoying news).
As you can see by the pictures, I got all the motors installed and locked down.
Z motor/shaft also completed. In this I used the Universal Mount plate.
However I found the V2 F plate was to tall, and the spots for the bolts did not match/align up with the hole spacing in the Z pipes (75mm) so I used openscad and modified the STL, printed it (in transparent PLA) and it aligned perfectly (as you can see in one of these pictures). This upgrade plate (both new STL and openscad script can be found at universal Mount MPCNC model F.
Next item was I really (all prop’s to the creator of the MPCNC), but I have had a real problem glueing in the M4 nuts in the Z axis nut trap from the original design. either it doesnt line up with the hole, or the glue didn’t bond and screwing the bolt in, just pushes it out.
So I went and designed a different one (also as STL or Openscad) for the Model F, this with a friction based sliding cover to trap the nuts in (also pictured below half un-slid). This can be found at MPCNC F NutTrap with cover
Anyway. Its all screwed down fast, and slides REALLY smooth.
In One of the photo’s you can see a rectangle in pencil on the spoil board and a small part of the side runners. This is the work area of the MPCNC when it is hitting the max area. I just put a pencil in the dremel mount (the grey printing item in the universal mount) and dragged it around at the max points. Easy.
And now for the annoying news. Today I went to attach the GT2 pulleys I got a month ago, only to find they were 8mm bore, not the 5mm for the Nema 17 motors. So while I can use the 8mm bore pulleys in another project, I had to send off an order for another set of 5mm pulleys. 🙁 as such I cant do anything more until they arrive.
Anyway. So far all is going well.
Attachments:November 19, 2016 at 11:58 pm #21217
Firstly – Can some one move this to Builds and Things Built forum, since I don’t seem to be having any problems getting started.
Secondly – Its alive! ALIVE!
will post video link shortly (just transcoding and up loading) but I got the new pulleys put the belts on, (ahh had to mod the tensioner from thingiverse) and wired up the ramps board, tuned the DRV8825’s, made up some Quick and Dirty series splitter cables (for X/Y), flashed the firmware, and plugged it all in.
And it worked first time. … 🙁 but I think my steps per XYZ (I changed them from the mpcnc default) are wrong.
But it still works, using the LCD I moved it up/down, left/right and forwards and backwards!
So next is the proper wiring.November 20, 2016 at 2:59 am #21220December 4, 2016 at 1:01 am #22031
Okay I went and got a T slot bit which fits a M5 hex head bolt nicely.
As per the picture attached you can see its in the MDF 16mm thick spoil board I have. lines not the straightest, but it will do.
now to print of some parts holders for the 2 slots I cut in the board.
However when I was doing this I found that event though I had the bolts tightened on the F-Z-Motor (where the Z motor is attached) around the Z pipes it still vibrated up (and hence the spindle went down). (see second picture).
As such I have just finished redesigning that part to have 2 holes in it so a bolt can be (after drilling) put all the way through to insure the motor doesnt move with respect to the vertical pipes.
After all Dust gets in between things (bearings, but also…) such as the clamped secured Z plate. And as we all know Dust can act as both an abrasive medium (in bearings) or as a lubricant (on pipes).
Anyway. will continue on trying this out.
Attachments:December 4, 2016 at 7:43 pm #22073
I have the same problem with my Z axis, the motor mount slides against the tubes.
I was thinking of making two little caps that would fit in the tubes and would be locked in place by a screw.
Seems better and more reliable to me than redisigning the motor mount.
Nice build though, congrat’s 🙂December 5, 2016 at 2:48 am #22082
Okay this is my replacement F-Z-Motor part. I extended it thicker, and then put 2 M4 holes all the way through. I the picture you can see the M4 x 65mm bolt(and nut) are present in one of them. But the holes are there on both sides.
Unfortunately this V1 is a fail, as I extended the cowl around the motor shaft, and as such side access to the securing pineapple (or rigid coupler, your choice).
So I am printing out V2 now with space for it. Once I am confirmed it works I will post on thingiverse as a remix, and put the link here.
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