Hi Dave
congratulations, I don’t use the components to orientate the items, the pins are labelled and a far easier method. Don’t forget the steppers need to be wired in series. If you need any info just call (Madingley) 210
hope to chat soin
regards
Making good progress on prints and electronics all motors working ok with the DRV8825 drivers in the initial 3 driver setup currently still on the Arduino Mega and Ramps 1.4 board - as the A4988 smoking issue doesn’t seem to have affected the other components.
Have made up some dupoint extension/splitter cables for the X and Y steppers - not sure how long to make the cables for my initial 300x300 build space as I didn’t spot cable lengths on the calculator. So may have to trim or extend them later. Initial lengths I have created are one set of 1020mm+1540mm, plus another set of 1350+2060mm (not sure whether X or Y will need the longest). The Z axis currently has only 1000mm at the moment so I presume I will have to create an extension for that too.
The cut pipes have arrived today from Metal Mania. Really impressed by the quality - seem to be within 0.1 mm of 25.4mm all around and cut lengths are perfect. The good/bad news is that the metal is much harder than the Screwfix conduit - so for the legs which I didn’t ask them to cut have found it really difficult cutting them (on reflection I should probably have paid the extra £15 to get them to cut all of parts). Initially tried the pipe cutter but that seem to go blunt before one cut. So tried 3d printing a measure Mitre and hacksawing them - but couldn’t really get very a straight line and have some nice blisters too. So might have to try and use an angle grinder. Or may just settle for the Screwfix 24.5 pipes for the legs as I guess the width and consistency of the very short leg pipes isn’t anywhere near as critical for the axis and they are much easier to cut.
All parts now delivered - so all I need now is to do about another 30 hrs 3d printing. Even though the PRUSA MK3 seems almost faultless I don’t yet have the confidence to leave it going overnight or while I am out - so suspect this is going to take a fair few more days. I also have a Flashforge Finder that is gathering dust at the moment - so might start that printing too in parallel tomorrow to speed things along a bit.
Really enjoying the build process so far and can’t wait for the initial CNC testing.
Excellent news.
take you time and enjoy, the more precisely you build the easier to get it setup and working.
i designed my own suction foot as these CNC routers can be extremely messy.
Any advice, Im here…
regards
Making progress. The parts seem to fit together ok - such a fantastic design.
The biggest problem is that I can’t get the tool mount to print completely straight (slightly bent at the bottom) - tried twice on the prusa - the second time much slower on smaller later height - but same result - not sure what’s making it lean over. Will try putting it together and see if it affects things - if so will try reprinting on the Flashforge which only moves the bed in the z direction to see if that helps - or maybe redesign it so it can be printed flat without loads of supports.
I like the sound of your suction foot - I was thinking something like this would work well
https://ooznest.co.uk/product/cnc-dust-shoe/
Also have to rework the stepper motor splitter cables and I just reaslised that despite your warning I wired them up in parallel rather than serial![attachment file=76811]
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Hi Dave
yeah, the wiring was one thing is struggled with to begin with but then I drew a simple diagram and it was far easier. If you would like, I could print the tool mount for you, if I start it over might it would be ready to post AM.
my suction shoe was a mishmash of some off thingyverse, I tried a few off thingyverse but none worked.
This is is my design and can contest it works superbly with zero mess
[attachment file=76817]
Suction shoe looks excellent - will have to sort out an appropriate vacuum and print something similar myself. Did you cut the transparent material on the MPCNC?
Thanks for the offer of printing out the mount - I will have another couple of goes tomorrow - and if they both fail I may well come back to you to take it up.
Ofcourse, yes the clear acrylic was cut using the MPCNC. I have just started a new project and this time a 4m RC Glider. been digitising the plans this weekend ready for cutting.
Again on the MPCNC, which was the main reason I made one…
It moves! Now to work out how to use it!
Really impressed at how well the centre part all goes together - had to take it apart a couple of times to correct bolt directions etc.
[attachment file=77013]
ps/ managed to print the tool bracket better by rotating it 90 degrees on the x axis -
[attachment file=77012]
3 Likes
First drawing worked ok - next stage I guess is testing the scale and calibration.[attachment file=77027]
Lots to learn. What is your emergency stop button connected to - the reset on the Arduino?
Hi Dave
CONGRATULATIONS. Always a relief to see it work.
good to see you started with the now compulsory Crown.
I Wired the emergency STOP inline with the powerswitch. Trust me, during the
learning phase it as been a god send. Saved the machine on several times through wrongful
programming on my part.
I also wired in the Z Stop for zeroing the bit tip.
When you start cutting, think about having a sacraficial board, another fine addition
As for calibrations, if you used the suggested hardware and have the correct firmware loaded, you should need no adjustmenst. I did the 100mm x 100mm movement test and it was spot on.
regards
1 Like
Evening Gents
Well after a few weeks of tinkering and cutting for the sake of cutting, I have decided my next project will be a
[attachment file=“Red-Bull Blanik Glider.jpg”]
I have just finished digitising a set of plans and hopefully the finished aircraft will have a wingspan of around 4 Meters. Having said that, with the cam software I use it would be very little hassle to even make it at 6 or even 8Meters…
Now i need to obtain a shed load of ply, spruce and balsa wood.
I have also started designing the decals and will cut them on my vinyl cutter or as a thought, attach a rotary knife to my MPCNC and away we go…
The canopy will be made using last years Project which was a vacuum former.
regards
P.S A massive dose of gratitude for your design… Cheers Ryan
4 Likes
4 Meters!?
That is correct Ryan. Using the MPCNC to cut the ribs, and formers.
I may even just scale it by 1.5 or 2 and end up with 6 or 8 meter…
regards
Making progress on initial tests with my new MPCNC - really impressed Ryan with the rigidity - have mounted a quite heavy old JCB router on it and doing some initial tests - setting the speed to the lowest setting of about 8000 RPM.
Taking quite a while to get familiar with Repetier Host and Fusion 360.
Initial problem related to setting zero position - I think I eventually figured out that I needed to create a script to send once I had manually found the top of the material - with
G92 X0 Y0 Z0
@isathome
Have then been able to successfully ream out a hole in some foam and also some wood - using Fusion 360 and MPCNC Mill Laser post processor, then Repetier Host to send the gcodes.
The problem I am having however is that all works well for the first print - apart from at the end as soon as the print is finished and the power drops to the steppers the Z axis seems to drop about 5 mm - possibly due to the power loss and the weight of the spindle.
Is that normal behavior or am I doing something wrong - because what I really wanted to do was run one print, then immediately run it again and for the bit to just follow the same path - with nothing to cut out the 2nd time.
I am sure I will figure it out - maybe I want to power left on to the steppers at the end of the print somehow by searching the forum.
Only other problem I am having is the occasional clicking when raising and lowering the Z axis - I presume it must be something loose.
My firmware should hold the steppers for 6-15minutes (depending on the version I just recently upped it). Check to see if you are powering them off in your gcode (M84).
Look for interference, and check your plunge and rapid speeds for your z axis. Could be physical or electrical.
Thanks Ryan - found a setting in the printer config - disable motors after ‘job/kill’ - which I had read as ‘job kill’- turning that off seems to have done the trick with the dropping of the Z on my foam tests.
May well have to consider some sort of Z probe or supported parking position if I find the dropping after 6-15 mins an issue
Will investigate the clicking further - must admit that I mainly heard it during test when the spindle wasn’t running - so hopefully it is not interference. I don’t currently have shielded cables - but may well try that if I can find a suitable place to source them.
It is usually bad rapid values. Limit your rapids to 8mm/s on the Z and work your way up until you skip a step. 10 is plenty fast for me.
Great thanks - lots for me to learn - which will hopefully also be useful for 3d printing too!
I did an M503 - and got:
20:21:31.885 : echo: M203 X190.00 Y190.00 Z30.00 E25.00
So I have put an M203 Z8 into my ‘Set home’ script - I will see if this does the trick.
Hi Dave
i have this process when using Repetier Host,
i firstly, use my touchscreen and zero z, as you know I have the z endstop setup for is process. Once I have Z zeroed, And the bit placed at the corresponding start position to the GCODE, usually left side and the front of the material. I Astro repetier host and connect to my MPCNC, this sets the RH software to X0, Y0, Z0 and the away I go,
im sure there must be a quicker or easier way but this is a way that I find easy…
regards