Awesome as always.:beer:
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Awesome as always.:beer:
Looks awesome! Getting really close to being finished now I guess?
You must be extremely proud - it's going to be fantastic.
Sorry been away from the forum again
Thank you Clive, Bert, Zeeflyboy for the kind words. I’m very pleased to get this far and have tried to make the best machine I can.
Yes I have motion at last but there is a list of tiny jobs to sort out including:
Proximity switch mounting and wiring in for both home and limit functions
Proximity switch targets
Z home proximity bracket
Small connecting brackets to finish the gantry installation
Rewiring the spindle back to a removable plug with a longer cable which goes through the energy chains this time
Water cooling pipes, tank and pump fabrication and installation
Lighting
Mist spray
Belt guards
Mag base mounting plate on Z axis for DTI
Mounting the spindle
. . .
Skimming the bed
Squaring the gantry and getting the home switches on X axis aligned
Tramming the spindle using the adjustment screws
I think that is it?
Then let’s see what she can do !
Sorry for my language - i think is not a perfect (Nederland)
Im very interesting of your router CNC - is it possible to send plans for me via email ??:sentimental:
I don’t have detailed plans that someone could follow. I’ve made changes along the way and it is quite a complicated machine.Quote:
Originally Posted by Vulcano
However I plan to put overall dimensions in a future video as a start point for other people to start their own design from.
Episode 22 is now ready . . .
https://www.youtube.com/watch?v=E6pr...ature=youtu.be
Looking awesome as ever - looking forward to seeing it at work, it should be a beast!
Thanks Zeeflyboy. Good thinking, maybe I should call it El Beast ? 😋Quote:
Originally Posted by Zeeflyboy
Enjoying your beautiful build also, great work.
I have been following along your build, it is really inspiring and also your gantry rigidity spreadsheet helped out a ton in my design, thank you! I do have a question, I noticed in episode 22, your spindle connector is not the original connector that came with, it's got a strain relief, can you point me to where I can find those? I've searched on McMaster and no luck. I know it is metric, do you happen to have the dimensions? I measured it, its something like M19x1 thread and 22mm OD. Any guidance would be appreciated, thank you!
Thanks 1nbcnc. Glad the old spreadsheet is still helping people out to get a feel for it all.
The original connector plug that came with the spindle was either GX16 or GX20. Certainly that style anyway. It was many years ago so can't remember if it was 3 or 4 pin. I think it was 4 and only 3 pins were used in the socket on the spindle side (going to the 3 windings in the motor). I added an earth cable from the spare 4th pin on the spindle side to one of the screws behind the end cap and used 4 core CY shielded cable to wire it up to the VFD. Note there is not really any strain relief with the GX16/20 connector.
This all went well for many years until one day there was a large blue flash from the connector and it damaged the VFD beyond repair. After years of use the repeated movement of the cable pulling at the connector plug it had loosened the pin connections and it arced. This is fatal for VFDs as they must not see a spindle disconnect when running.
Adding a strain relief above the connector had been on my to-do list, but you know how it is, just one more job to cut and then maybe I will get around to it. Well, it served me right.
So after that I wired the cable DIRECT to the windings, including an earth, and added a cable relief grommet which passes through the hole in the cap and has a nut on the back. 22mm hole in the end cap rings a bell but I really can't be sure as it was many years ago. This is what you saw in the video, the old strain relief grommet. What you then saw me do in the video was replace this with a longer cable, but it is still DIRECT wired to the spindle with the strain relief to manage the stress. This means it cannot be quickly disconnected.
It is similar to this one, but I think it might be a bit larger. Next time I am out in the workshop (sorry, not this weekend and at least the following weekend) I will see if I can measure anything although the spindle is buried in the Z axis.
https://www.ebay.co.uk/itm/Spiral-Ca...UFt:rk:18:pf:0
Many on this site would recommend fitting a removable connector AND strain relief after it, and I would not argue against it. However, I've had no cause to remove the spindle, and I know with the direct wiring and long strain relief grommet it should run OK for a long time. Hope this helps.
Thank you! That's helpful, I will certainly give your suggestion a try.Quote:
Originally Posted by routercnc
On a different note, have you had any challenges with the ball screw lock nut in the past? I noticed on my router that the lock nuts will back out when the gantry is moving in one direction, I know that the lock nut is supposed to preload the inner race of the AC bearings, and the set screw on them are so tiny and I can't really torque them hard or they will strip, to be honest the set screws don't seem to work that well. I've seen people order ball screws with a longer thread for two lock nuts back to back, but it's not an option for me any more. Any suggestions or solutions would be appreciated.
Thank you!
I have had them come loose occasionally over the years. I've always managed to tighten the nut and carefully tighten the grub screw but yes there is the fear of stripping the thread or more likely rounding out the allen key hole.
Other options to think about:
As you say, longer screws and double lock or jam nuts
Maybe blue loctite on the nut but don't get it near the bearing, or maybe PTFE tape??
Dropping a short length / disc of brass rod in the grub screw hole first, then the grub screw will mold it onto the thread
Making a brand new nut from steel (and then heat treating it) with a larger grub screw?
Anything from anyone else?
The other thing to think about is how to hold the ball screw when tightening the nut (once it is all installed with coupler on etc.). I fold up plenty of shop towels into a narrow strip about 30 mm wide then wrap it around the ball screw. Then apply as much pressure as you dare using a mole grips . . . . . pause while I find the US name for such as tool . . . . vice grips, to hold the ballscrew and tighten the nut using a spanner/wrench.
Thank you for all the suggestions, I will give them a try for sure.Quote:
Originally Posted by routercnc
I use oneway bearing wrench to hold the ballscrew when tightening the nuts.
Also, my SYK bearing holders have nuts with setsrews, but the thread hole does not go all the way tru so you don't destroy the ballscrew threads.
This is my wrench:
https://www.amainhobbies.com/align-f...t00005/p213519
Thank you for your suggestion, I will give that a try as well.Quote:
Originally Posted by jkkmobile
Think that's This Old Tony that uses a hardened steel ball under the screw to create a "single point" of contact and increase the pressure on the shaft.Quote:
Originally Posted by routercnc
Could even have a video just about that IIRC
Envoyé de mon ONEPLUS A5010 en utilisant Tapatalk
Yes, for a plain shaft that is OK but remember this is pressing down onto the thread. A steel ball would damage the thread making it difficult to remove the nut so the brass disc is a better option as it is soft and will mold into place.
SYK nuts have brass inserts:
https://www.syk.tw/en/product/201705040003
You can buy them from resellers like cnc4you:
https://www.cnc4you.co.uk/BK12-12mm-Nut?search=Nut
Episode 22 is now ready ok hmmm when you planing episode 23 with some mesurment\s ??Quote:
Originally Posted by routercnc
It could be a couple of weeks away based on the little free time I have at the weekends and the long list of things to finish off.Quote:
Originally Posted by Vulcano
I have been doing a bit here and there and filming short sections. See if you can spot the joins !
I'm eagerly waiting for your actual ali cutting video and hopefully some stiffness measurements.Quote:
Originally Posted by routercnc
I have a questions as I'm starting a new build trying to use some of your design solutions.
Have you researched or tested how the double beam gantry with the rails on top (80-100 mm more leverage) performs in the Y direction compared with the twisting of the popular single beam gantry?
You have mentioned at some point that mori seiki used this gantry design but I couldn't find any information. Could you point me where to find anything about it?
Here is the pdf link for the Moro Seki 5000Quote:
Originally Posted by paulus.v
https://uk.dmgmori.com/resource/blob...0-pdf-data.pdf
This shows the box in box idea which was part of my inspiration.
I was worried about rails on top as they are further away but when they were underneath they were difficult to level plus would get chips and coolant on them or risk being hit.
On the sides made the gantry even wider which I didn’t like. When I saw the Mori rails on top and the beefy construction I went with that.
I have not measured the stiffness yet still other jobs to finish (build coolant system, skim bed, tram head, belt guards. . .) and other commitments are limiting workshop time but we will get there and get a video out when it’s done 😀
Thank you!
That dmg mori machine is a real beast. The blocks spacing on the Y rails is greater than the travel distance... And everything looks like cast iron. It is great that they put a lot of technical details and images in that presentation.
I never thought to put the rails hanging under the gantry with all that ram weight trying to snatch off the rails...
One more question, what is your gantry (rails) total length and travel distance?
re tightening the retaining nuts, you can also dremel a little flat head screwdriver slot into the end of the ballscrew shaft and use that to hold the shaft still while tightening the nut.
Well I say "you can", I've never seen anyone else do it but it soother's probably a really great reason why not to, but it works for me! No more worries about damaging the important part of the screw vs not tightening it well enough.
https://i.imgur.com/JpyoZXO.jpg
Nice idea. I was thinking of flats machined on the end or on the last part of the ballscrew behind the housing but a slot looks good as it still supports all of the pulley. My other thought was that with the right equipment you can wobble broach a hex pocket into the end.Quote:
Originally Posted by Zeeflyboy
Paulus, rail is about 700 long and travel is currently 360. I could go a bit more but when the spindle is quite low nearer the bed it would hit the sides so have limited it to that.
Episode 23 is now ready . . . . . finishing off ready for first real chips !
https://youtu.be/5KOWKN2rFi4
Well done mate, certainly one of the best DIY builds I have ever seen. The attention to detail is immense.
In the cutting videos, the spindle bogs down. What power is it? Are you running full speed?
Hi Chaz,
Thank you. I can't tell you how relieved I am to have finally 'finished' the machine (they are never truly finished are they?) and I can spend some time with the family again. I hope it gives some ideas and inspiration to others.
Yes, the spindle is a 1.5 kW Chinese spindle and I knew it would be the next limiting factor. I have other designs in CAD for various spindle options but they will have to wait for now. It works, and I can certainly make a few hobby parts with it.
It was running at around 12,000 rpm in the film (full speed is 24,000 rpm), with a 6 mm 2 flute 45 deg cutter for aluminium, with the approximate WOC and DOC shown on screen. Feed rate varied - the heavy cuts were around 700 mm/min and the finish cuts were around 1400 mm/min. I finished the tram and final build yesterday morning, and I basically had about 20 minutes yesterday afternoon to get some cutting footage before my 'time was up' so basically went for it. Although I didn't have much time to experiment I soon found the limits. I actually broke the tips off both flutes by being so aggressive.
Much to think about and reflect on over Christmas, but first a break !
Nice to see it finally finished and making chips. It certainly is a big credit to you and I have enjoyed all the vids in the making.
Ok, that makes sense. Go 24K, anything less has even less torque. I'd fit the largest spindle that you can in there, clearly limiting the machine. Congrats once again.Quote:
Originally Posted by routercnc
Thanks Clive. It’s been a long time coming !Quote:
Originally Posted by Clive S
OK I’ll try some other speeds / feeds next time
I enjoy so much the build and the detailed video you upload.
Thank you so much about all the effort and the documentary!
Great machine!
Thank you. There should be more videos in future but time for a break !
Congratulations on a phenomenal build. What ever i write i feel i won't do you or your build justice. Love the videos and would love to see more of your projects.
Thank you ! Feels good to have finished it - or at least get it working (already thought of a few tweaks here and there).Quote:
Originally Posted by Fancy
Something I asked about along time ago on this forum and received plenty of help on (thank you!) was getting the 24V prox signal into the 5V breakout board. In ep22 you saw the circuit that was recommended to me but I have found it a bit unreliable and actually crashed into the sensor on one occasion. So I did a bit of searching and tried a diode in the black wire from the sensor (bar pointing to sensor I think?). This works very well without any issues and gives either a solid 5V or 1V when switched. The diode I had to hand was a generic 1Nxxx type which is meant for relays (?) and such but have since bought a proper switching diode (not fitted yet) which I guess is much faster or at least more suitable. When I’m back at the PC I’ll post a diagram for the electrical guys to comment on.
..and finally making chips after a 3 year journey! Congratulations!
I would be grateful if you could measure the stiffness in the x and y directions.
What breakout board/ controller are you using? Does it have optocouplers on the inputs? I had the same problem feeding 24v signal to 5v bob. In my case the signal was fed to the optocoupler through a current limiting resistor with a value calculated for 5v input. I just had to replace the resistor with one calculated for 24v.
Thank you Paulus. Great to have it working like it should.Quote:
Originally Posted by paulus.v
I was planning to measure the stiffness and compare to my old machine, plus a typical commercial stiffness. Depends on when I can get another slot in the workshop. Probably a bit rude to do it when the in-laws are here - although . . .
The breakout board was free with the drivers and is very basic. I think it is called a DB-2505. ?
From memory it has black chips near the inputs which I always assumed were optocouplers. Replacing the resistor sounds interesting.
Time for one last video in the series ! Some finishing touches . . .
https://youtu.be/vd-Ly1454rw
Still plan to measure the stiffness - I may get a chance to get in the workshop today and report back tomorrow on this thread . . . sorry for the delay
Many thanks routercnc for an absolutely awesome build!
Apart from the build aspects that relate to your specific CNC design (some of which is frankly way too complex for me to contemplate), I have learnt so much from your videos about what I can only call "general machining principles", which I would never have learnt otherwise!
Thanks again,
Andy