Timescapes - Digital Timelapse Discussion

CNC Router Build
Page 9 of 12

Author:  edward [ Wed Nov 29, 2017 6:23 am ]
Post subject:  Re: CNC Router Build

Re the quality of BK mounts, for my mill I first bought some cheap ebay knock-offs. They seemed OK but they had quite a lot of backlash. Then I bought the TMT grade c7 made in Taiwan and the backlash was much, much less. Grade C5 are even better, with much better bearings that can take preloading, unlike the bearings in the C7 versions which you musn't tighten too much.

Glad you are finally cutting something, looks round enough, (from a distance, hehe).

Author:  DISPLACEMENT 1 [ Wed Nov 29, 2017 6:56 am ]
Post subject:  Re: CNC Router Build

Prob going to get better quality connectors and call it a day fed up of measuring things . I am a maker not a measure-er !
But you will be pleased to Know just cut out 100mm hole and a 100mm disc and it fits perfectly and when turned no binding. It seems to measure 99.95 mm though but its only 6mm MDF so not the best tests but not set up yet so gantry out of line prob and spindle out of whack prob.
6mm cutter going 3.5mm deep at 2000mm/m spindle speed 10000 got the feeling spindle could do with going a lot faster and should be able to cut in one pass really.

Author:  Kitwn [ Thu Nov 30, 2017 4:55 am ]
Post subject:  Re: CNC Router Build

A day or two ago he can barely get the gantry to move and now he's complaining that his perfectly round circles are out by 2 thou! Some people are never satisfied :o

Author:  DISPLACEMENT 1 [ Mon Dec 04, 2017 5:13 am ]
Post subject:  Re: CNC Router Build

Hi Kit been away a few days but yes i am satisfied for what i do .
Did a few more tests out of plastic stuff this time
120mm circle
[flickr]Image2017-12-04 11.09.42 by D 1, on Flickr[/flickr]
Close enought

And round
[flickr]Image2017-12-04 11.11.22 by D 1, on Flickr[/flickr]
120mm disc in 120mm hole

Also cut two boards at same time with four 6mm peg holes 280mm apart then rotated one board 90% and pegs lined up perfectly which means gantry was square even before setting up
[flickr]Image2017-12-04 11.10.36 by D 1, on Flickr[/flickr]
[flickr]Image2017-12-04 11.11.05 by D 1, on Flickr[/flickr]

Not so sure now though as i forgot to set soft limits and crashed gantry . As i have said this my issue with two steppers if i could get a belt long enoght i would go down to one Nema 34 set up like this .
[flickr]Image2017-12-04 12.51.52 by D 1, on Flickr[/flickr]
Also get the advantage of been able to alter size of pulley B to give different ballscrew speeds . Also no need for flexible couplers which i am have problems with

To much play which prob isn't helping with gantry locking up ordered some oldham type

Author:  edward [ Mon Dec 04, 2017 7:29 am ]
Post subject:  Re: CNC Router Build

Yes, those couples are too spongy for a big torque machine like yours. Getting Oldham couplers is the best thing you can do, I use Oldham couplers too.The middle plastic bits can shatter if they experiencer big obstacles.

Part of my order has come today, the ballscrews will arrive tomorrow, I'll let you know my impression.


PS, I am not sure the belt will remedy your problem. It will still seize up if the ballscrews are too different from each other.

Author:  DISPLACEMENT 1 [ Mon Dec 04, 2017 8:04 am ]
Post subject:  Re: CNC Router Build

Think the ballscrews are not that much of a issue now . C7 at my length should suffer about .007mm drift dont think that would cause a lock up with a firm belt drive and as i say much better than any flexible coupler .
Just upped the Kernal speed on the old putter getting 5250mm/m on Z and Y no problem now i have re wired he motors. So yet again if i had a single nema 34 think i could match the speed of the Z and Y at the moment the max i can safely get out the X is 3500mm/m :(

Look forward to seeing how your build goes now mine is hopefully coming to a end :D


Author:  edward [ Tue Dec 05, 2017 4:35 pm ]
Post subject:  Re: CNC Router Build

The TBI ballscrews arrived today, they look very good quality. They included some plastic tubes to help remove the ballnuts in case I need to at some stage in the future. Having ordered double ballnuts to remove all backlash, they turn nicely, but there is a little more friction than with the ordinary cheap screws, as it should. The machining of the ends is fine too, with longer ends for the pulleys as requested. All in all it took exactly 15 days from the day I ordered. I am not sure if they will crucify me with Customs yet, the courier was Fedex.

For the Z axis I ordered a single ballnut, so when I do my measuring I will be able to check if having double ballnuts is at all necessary with quality C5 screws.

D1, do you use any particular brand or kind of double sided tape to hold your plastic down whilst it's being machined. Your circles looked good and accurate:)


Author:  DISPLACEMENT 1 [ Wed Dec 06, 2017 2:01 am ]
Post subject:  Re: CNC Router Build

Hi Edward no particular type of double sided. In fact i try to avoid it as it can be a pain to get off . I miss the vac bed on the bigger machines i have used . The speed of the spindle really wants lift and throw things about to . So i think it will have to be holding tabs in future or re positioning clamps as you machine :( .
This gantry locking up is really annoying me did a test bed skim in air at 3750mm/m with 10mm cutter took just under a hour not a single problem . Then i was doing some quick positioning and gantry locked up maybe need to turn down acceleration. Oh fitted oldham type connectors no noticeable improvement .
I can get long enough HTD5 belts but not steel banded . Think this may be the way forward as i need the extra speed the nema 34 will give me .
Hope to be doing stuff like this so speed is a issue

Dont want to get into servos and i am fine on all axis running at 5500mm/m except the X

Author:  DISPLACEMENT 1 [ Wed Dec 06, 2017 6:46 am ]
Post subject:  Re: CNC Router Build

Oh and off topic big time.
Yes this is my fault i seem to be a seasonal worker and the most perverse thing is dont even like Christmas !

Soz D1

Author:  edward [ Wed Dec 06, 2017 9:23 am ]
Post subject:  Re: CNC Router Build

Good animation, I enjoyed it. I don't watch telly much so first time I see it.

I hope you start cutting some 3D foam or similar soon, see how you get on. The carving in the video looks quite complicated, I will start with simpler shapes on foam and learn from that.

Author:  DISPLACEMENT 1 [ Wed Dec 06, 2017 1:12 pm ]
Post subject:  Re: CNC Router Build

Yep i will be cutting a lot of blue foam for the day job one of the reasons for the router .
By why i only had a small part in add sets and props as usual read my post and it sounded like i did the entire thing !

Author:  Kitwn [ Wed Dec 06, 2017 5:02 pm ]
Post subject:  Re: CNC Router Build

The animation of the girl dancing was trully brilliant, set in the context of some equally exceptional sets and props.

Good that the machine is now behaving, mostly, as you want. I still think the gantry locking up could be the motors stalling due to resonance effects and/or too much acceleration as you suggested yourself. Even my lightweight gantry driven by NEMA17 motors would come to a jarring halt with the acceleration set too high and it really does feel as if the whole machine has siezed rigid all of a sudden. Part of the trick of using steppers is being able to accelerate through the midrange speeds to get to the higher speeds you want. There's an article all about that somewhere, possibly on the Geko drives website. Obviously that's true regardless of how many motors and leadscrews you have on a given axis. Your idea of two screws driven by one motor, with the option to change pulley ratios, looks like a good idea to me and doesn't involve too radical a rebuild of your machine.

That carving is something to aim for!


Author:  DISPLACEMENT 1 [ Thu Dec 07, 2017 1:29 am ]
Post subject:  Re: CNC Router Build

Hi Kit are you still animating by the way ?
Back on topic think my main issue is i should have used Nema 34 for the gantry in the first place . Gantry prob weighs close to 50kg which is quite a lump to get moving . I assumed having two ballscrews would split the load and the smaller motors would be fine . This is not the case and if anything two ballscrews reduce the force applied to the gantry .
I am going to live with the smaller motors for the moment as i have spent far to much on this project already . But i will eventually upgrade to either a single 34 or two not sure which yet .

Author:  Kitwn [ Thu Dec 07, 2017 7:40 pm ]
Post subject:  Re: CNC Router Build

I enjoyed all the studying and learning and the making of my one and only animation 'The Fruits of Love' but it was so obvious that for one person to do EVERYTHING required to make a film was too much. Especially as I'd want to up the quality for another film. I'm better sticking to what I'm good at which is the more technical stuff rather than trying to sculpt puppet heads and build sets. After watching the dancing in your BBC Christmas film I'm never going to be able to animate to a standard I'd be happy with anyway. The GPS locked wooden clock is much more attuned to my actual ability.

I still have all the details of the flicker-free, high stability, dimable LED lights I made if you know anyone who might be interested in such things. There was quite a lot of stuff on one of the forums about problems with short term flicker in 50Hz LED lights and long term stability causing flicker in the animations back then, has that been sorted yet or are you still using hot tungsten?


Author:  DISPLACEMENT 1 [ Sat Dec 09, 2017 1:08 pm ]
Post subject:  Re: CNC Router Build

Hi Kit well at least you got one film out.
As for lights yes think tungsten on its way out not that i get in studios much these days .
If i ever had any problems with flicker i would just put a ND filler on and have a long exposer seemed to level everything out . Not that i have done much filming of late this router taken all my spare time .
Next week i am ordering a Nema 34 , drive and all necessary belts and pulleys . Twin motors work and most people would be happy but its just to hit and miss for me . With a single motor i always no the relationship between the two ballscrews is constant and i can dial in what ever speed i want by changing pulleys .
Found one article which seems to back up my thinking so thats enough for me http://www.cnczone.com/forums/diy-cnc-r ... tware.html Last post.
This way theirs also no issue with splitting step direction signals ,

Author:  Kitwn [ Sun Dec 10, 2017 5:11 am ]
Post subject:  Re: CNC Router Build

There's a lot to be said (but not much that hasn't already) about the benefits of dual screws or racks for holding the gantry square. I think the main reason for dual motors, certainly for those of us who don't use separate zeroing to pull that gantry square at each use, is that it's mechanically simple. two directly coupled motors, no belts and wheels to align and no belts crossing the base to get in the way of long pieces of timber sticking out at the ends. It's fairly cheap too if you use one driver with the motors wired in parallel as I do.
I'm not overly impressed with the design in that link you included though. Looks like he drives on screw direct with the short belt and then has a long belt going between them to drive the other. Your drawing with the motor in the middle and complete symetry on the one belt looks much more accurate to me.

One thing I'm worrying about with my current upgrade is my choice of 2mm pitch ACME screws. I thought this would give me loads of torque to avoid stalling ( and they were cheap, this is me talking) but I'm beginning to wonder if I can spin them fast enough to get a decent cutting speed. If not there's a rack and pinnion design option in Gearotic so watch out for a plywood rack! Or maybe I'll cut out some wax or plaster moulds (aparently you can cut plaster of paris with standard router tools and it doesn't blunt them) and use up all the two part resin I still have in my fridge.


Author:  DISPLACEMENT 1 [ Sun Dec 10, 2017 6:17 am ]
Post subject:  Re: CNC Router Build

Hi Kit the using ballscrews to pull the gantry square doesn't actually work . Its nice in theory but in reality no it puts to much unbalanced load and it will cause stalling . I found when may gantry stalls ya drive it backwards and forward and the ballscrews find their happy position this may not mean ya have a square gantry though and thats the rub!.
Yes i think belts are not popular with manufactures because its prob more expensive and requires more hands on setting up which again cost money. Its only do able on certain size machines i think mine is max ya could go .
Racks have their own problems you will prob want teeth down so machining bits dont get caught in the teeth . I am were i am at so to late to change that much . The more i think about it the happier i am with the belt idea . Yes the example i used was a bit messy i wont be doing that but speeds and torque seemed about right i .I will go for a 2.1 ratio so effectively giving me a 10mm pitch ballscrew and yes i think you are going to struggle with your 2mm pitch . Only prob i have now is finding right belt length dont want it to long . Looks like it will be HTD8 which also means i can get taper lock pulleys which is much better .
Yes i am aware of machining plaster its messy horrible stuff i use tons of it at work dont want it messing my shed up . Think will stick to machining wax its cheap and you can re melt it . Got all the ingredients for that now just havent got round to mixing it up .

Author:  Kitwn [ Mon Dec 11, 2017 10:10 pm ]
Post subject:  Re: CNC Router Build

I hadn't really thought about the mess factor with plaster, warning noted. I did wonder about cutting plaster moulds for casting complex aluminium parts but that's another of my 'this year, next year, sometime, never' projects of which I have so many.
Like you I have all the ingredients for making machine wax. Two big blocks of paraffin wax and a charity shop deep fryer to melt it in. It's cutting up the HDPE milk cartons by hand I'm not looking forward to, bloody hard work to get the bits small enough as it appears the stuff dissolves very slowly. I should get it done though, there's two part plastic going off in my fridge and an unused vacuum pump on the shelf for degassing it so it's just a matter of doing the work to try making some small gears and other parts for smartening up my clocks and other assorted projects.


Author:  DISPLACEMENT 1 [ Tue Dec 12, 2017 2:32 am ]
Post subject:  Re: CNC Router Build

Hi Kit i cheated and got some little pellets of Ebay wasn't that expensive . Like you say the smaller the pieces are the easier its to melt them down . Do yo have a garden shredder? http://www.diy.com/departments/b-q-elec ... GwodHYcEhg That would make quick work of plastic bottles maybe see what the charity shop as to offer :D .
Well had final refit off gantry etc and selected a safe speed so gantry dosent lock up and you guessed it gantry not square . My first fit and test must have been a happy accident . So will have to strip down again and re align not a quick processes . Lets hope gantry doesnt lock up again !.
On speeds actually been cutting some mdf must admit with the bluntest cutter in the world but all i had . But a good spindle speed and feed seemed to be 18000 for both . So thats within the safe speed for may gantry (2500) . So could live with it but i do want to cut a lot of polystyrene ?blue foam and very quick speeds would be good . So i Nema 34 will be going on at some point .

Author:  edward [ Tue Dec 12, 2017 4:38 am ]
Post subject:  Re: CNC Router Build

D1, I feel your pain!

Seems like the belt idea with one single motor is the way for you to go.

Still, this leaves a lot of unanswered problems. There are a lot of routers out there using twin motors with no problems, as Kit says. So if the screws are not the problem, and you are certain that the commanded destination is bang on with both motors/screws, then something very strange is happening. It will be interesting to see if I have similar problems as I am using completely different electronics to you. I also have the option to go for belt if everything else fails:)

Author:  DISPLACEMENT 1 [ Tue Dec 12, 2017 6:09 am ]
Post subject:  Re: CNC Router Build

Hi Edward its just that i am trying to make the motors go faster than they want . If i stay below 2500mm/m all fine . But everybody will have a gantry lock up when they are setting up a machine how else do you find the top limit . Thats when the two motors will push something out of alignment theirs no way they are going to stall at excatly the same step . .
I was taking to somebody the other day their router doesn't cut square its a 8x4 Chines . I suspect the gantrys locked up at some point (it was seconded hand ) and the motors have punshed it out of alignment . Prob just needs setting up again . I didn't volunteer my services bit fed up all things CNC at mo .
I think in my case a single high torque motor with a 2.1 ratio belt will give me a lot less trouble in the future .Another plus point is it wont take much to put a belt on the Y that way i get quicker speeds on both axis :D .

Author:  edward [ Tue Dec 12, 2017 6:54 am ]
Post subject:  Re: CNC Router Build

So with your psu/driver/controller combo you are safe at around 500rpm. If you double it, i.e. 1000rpm. you start to have problems.

I don't think 1000 rpm with sufficient torque is too much to ask so long as you haven't applied a lot of micro stepping (max 1600) It probably boils down to the limitations of your electronic devices.

I will finish my PSU in a couple of days and I will then try a 3.1Nm stepper at various micro step settings driven at 68V with a nice digital driver and a controller than can provide the necessary pulses, it will be interesting to see some initial results.

Author:  DISPLACEMENT 1 [ Tue Dec 12, 2017 8:21 am ]
Post subject:  Re: CNC Router Build

Those 1.5m ballscews take quite a bit to turn they want to dip in middle down to their own wight .On the Y i can get up to 5500 mm/m no problem. My Y Prob equivalent to your X . All the 8x 4 routers i have used have been rack and pinion and nema 34 . Makes ya think :(

Author:  edward [ Tue Dec 12, 2017 9:15 am ]
Post subject:  Re: CNC Router Build

Yes, maybe that's part of the problem: long and thin ballscrews, so resistance around the mid distance due to bending. I am not sure if you went for the 20 or even 25mm or just the 16mm which would seem a bit thin for such a monster router...

My long axis is 900mm minus 250mm occupied by the Hiwin blocks, so exactly 650mm cutting area. If I even need a bigger router, I will definitely go for a good brand second hand and maybe do some updating or mods where needed. At least you start off with a good framework. I am sure I have spend more than 4K on materials and electrics alone, but that's fine because I couldn't find something as well specced on the market for such a small frame size, and believe me, I looked around at the time. And then there is also the fun of making your own, that's got to be worth a few quid:)

Author:  DISPLACEMENT 1 [ Tue Dec 12, 2017 12:55 pm ]
Post subject:  Re: CNC Router Build

The fun of making your own Hmm ?
Well i am getting their believe it not . The x axis's ballscrews are 20mm and yes it would be easier to buy a second hand one and upgrade . But size was a issue and 4th axis which is set below the bed on mine would be hard to fine . So like you i have to build the specs i want .
So this is ware we up to it actually looks like a CNC router now :D
[flickr]Image2017-12-12 17.22.08 by D 1, on Flickr[/flickr]
[flickr]Image2017-12-12 17.21.54 by D 1, on Flickr[/flickr]
Just got to fit stop switch and mister control to gantry . The bed is just MDF at mo will skim it tom not sure about slots yet will use it for a while and see which layout is best . Got a few clamps to make tom as well then that should be it until i upgrade all the issues .
Best way to square the gantry is by putting a engineers square on the hiwin blocks . Theirs a nice ground surface on one side of them make sure you put that inwards.
Then run the Y along the length of the square i have just eyeballed this at mo as i need to get a better square but when i do i will put a gauge on it .
[flickr]Image2017-12-12 17.00.39 by D 1, on Flickr[/flickr]
Was looking at your design Edward cant see any wiring management have you got a clever plan ? :D

Author:  edward [ Tue Dec 12, 2017 1:59 pm ]
Post subject:  Re: CNC Router Build

I must say, it looks very nice and professional. Mind all the carcinogenic dust when you skim all that MDF!

Thanks for the tip about aligning the gantry. I am sure you've gained a lot of experience having to do that so many times!. I have a long engineer's square that will come in handy. Do you have a clever way of adjusting the home switches? I haven't thought about these yet, I think I will use my proximity switches but will have to have a way to calibrate the distances so they both cut off in unison. Would appreciate some pics about that when you have some time, as I need ideas. But one thing at a time.

Hope your pulley system works, you are using a bigger pulley pitch than the usual 5mil because of the length of belt...did you also try AT5 at your required length?

You could also have made to length AT5 jointed belt, though I don't know how strong it will be, they say it's about half the strength, which may be more than enough for driving the ballscrews under load, I don't know.

Author:  DISPLACEMENT 1 [ Wed Dec 13, 2017 6:34 am ]
Post subject:  Re: CNC Router Build

Well had dusty and noisy morning skimming . Spent a life time covered in MDF dust so if it hasnt got me yet ?
But all went well only took off .2mm ish so bed was very flat to start with . Used a 1inch flat bottom thing haven't trammed the spindle yet but cant find any lines on finished result . So all the lining up with a spirit levels and bits of fish line may have paid of. Epoxy really does find a accurate level .
[flickr]Image2017-12-13 14.11.44 by D 1, on Flickr[/flickr]
[flickr]Image2017-12-13 14.17.52 by D 1, on Flickr[/flickr]

And as i say its noisy !

Only got one limit switch on the X Edward as the step and direction signals are split thats all i need.

[flickr]Image2017-12-13 14.11.22 by D 1, on Flickr [/flickr]

Yes the Htd 8 just for belt length options never used that size before but cant see why it should be a problem . Also my ballscrew dont have a flat or keyway so a taper lock bush fixing should be a good way of securing the pulleys .


Author:  edward [ Wed Dec 13, 2017 10:19 am ]
Post subject:  Re: CNC Router Build

You certainly can't see any lines at all. Mind you, wood is very forgiving, but still, it has to be said, it looks good.

For pulley locks I use these often:


Sometimes these:


Re the proximity switch, I forgot you only need one, as you are splitting the signal In my case I will need two, as each motor is independent.

Almost finished the PSU today, haven't connected it yet, I'm double-checking all connections as this is seriously dangerous stuff if you don't get it right, things could go BANG! Photos to come if I am not electrocuted in the endeavour:)

Author:  DISPLACEMENT 1 [ Wed Dec 13, 2017 12:01 pm ]
Post subject:  Re: CNC Router Build

:D Yes thats one thing that puts me of building power supplys .Also had nasty shocks of capacitors in the past 240v doesn't seem to bother me.
Used the first type of couplers before but not the second . Prob be using these http://www.beltingonline.com/timing-pul ... -lock-568/
Bit cheaper and seem to work, easy to get off the first one you speced i had problems getting off again .

Cant find any keyless one but dont think it matters i will apply some loctite once i am happy .
Yes timber more forgiving but remember its a 1inch diameter cutter so not bad. I will do tramming once i have a ali bed and changed all the other things though .

Author:  DISPLACEMENT 1 [ Thu Dec 14, 2017 11:55 am ]
Post subject:  Re: CNC Router Build

Well had a go at machining aluminium not good a difficult nut to crack ! In fact that difficult i have ruined every single ali cutter i have :(
Main problem seems to be gumming up i dont want to use coolants but not sure how to get round it . And its noisy in a unpleasant way. I will try running the spindle at slower RPM when more cutters turn up. But you can only go so slow, spindles not good at that . Maybe the MDF bed is not helping but it does seem hard to get a initial decent cut no chips are been produced at all.
I was hoping to do stuff like this
[flickr]Image2017-10-25 19.23.07 by D 1, on Flickr [/flickr]
This was done on my small mill went down to a 1mm ball nose cutter . Cant imagine ever been able to use such a small cutter with a spindle unless i have a revelation.
On timber front no problem at all munches through 18mm Ply and MDF easily . Best tip i came across was when you have finished cutting something touch the bit . If its to hot to hold either the spindle is going to fast and feed rate is not enough causing the bit to heat up . So with a bit of experimenting i have a list of good settings now .Its just the ali thats proving a problem which is a shame as thats the main reason for the machine :( .

Author:  edward [ Thu Dec 14, 2017 2:21 pm ]
Post subject:  Re: CNC Router Build

Well, there are lots of guys cutting aluminium on crappy little chinese routers and they do very well, so there is no reason why you shouldn't. Your machine is robust!

Have you tried less demanding cutting tasks, like holes, channels and pockets? It could be your speeds and feeds that need some tweaking....You don't say what diameter cutter you have been using, I assume 3mm but maybe you are using smaller?

I have the G-Wizard Calculator if you want me to check some feeds for you? A conservative setting at 12000rpm with a 3mm 2 flute cutter would be around 450mm/m.

A lot depends on the alloy type as well. Some alloys are very 'gummy' Having said that, I will probably have similar problems when I try myself.

BTW, I've finished the PSU and I haven't been electrocuted so far! In fact it is working a treat. Tomorrow I will try it with a stepper and see what happens:)

Author:  DISPLACEMENT 1 [ Thu Dec 14, 2017 3:02 pm ]
Post subject:  Re: CNC Router Build

Hi Edward glad ya still with us .
Yeah just spent last hour watching a lot of flimsy machines quite happily cutting ali .
Think one of main problems was not going deep enough some say 1mm i was making dust rather than chips .
Secondly going to see how slow a can happily run the spindle and work up from their 6000 rpm as been mentioned for 2.2kw spindle .Did consider a belt drive reduction from spindle to get a lower RPM range . Sort of discussed hear http://www.mycncuk.com/threads/7156-mac ... kW-spindle.
Been using 6mm my favorite gummed those up and 3mm snapped those :( . Hopefully another batch will turn up tom but post been a bit funny at mo with the festive period and all .
May take you up on offer of a G wizard check will see if theirs a trial version may get me out of this difficult patch .
Also thought you might like this build similar attention to detail and quality you have .


Author:  edward [ Fri Dec 15, 2017 2:11 am ]
Post subject:  Re: CNC Router Build

I enjoyed the video. However, I am not sure about the large box gantry, it eats up a lot of cutting area and I am not sure he is gaining much, plus is the box hollow or has it got ribs inside...

Regarding the revs, you have a 2.2Kw spindle, like the guy in that post says, you can cut between 8-12K. JazzCnc has helped me with queries in the past and he knows what he's talking about, so cut deeper to get proper engagement rather than rubbing, but far slower revs. Time to burn money!

I admit, it's terrifying to sink deep in the cut and see the cutter snap, just like that, you've thrown lots of money away. BTW, I use a very good brand of cutters made for aluminium, they are expensive but they seem to last, they are the nicest looking cutters I've ever had, beutifully shaped and very sharp. Ask Santa nicely...


Author:  edward [ Fri Dec 15, 2017 2:37 am ]
Post subject:  Re: CNC Router Build

Here is the PSU. As you can see, very simple to make. I measured 71V without load, so it will be around 68V with load.I used 20x20 extrusion frame for the base so that the bolts underneath don't touch or scratch the table and to have something rigid to support the 2mm aluminium sheet, as the toroidal transformer is quite heavy.

I have included a bleeder resistor in series with a green LED to discharge the capacitors and see it happen. With the motors connected they will discharge very quickly, with nothing connected it takes around 4 minutes to fully discharge.


Author:  DISPLACEMENT 1 [ Fri Dec 15, 2017 4:44 am ]
Post subject:  Re: CNC Router Build

Hi Edward that looks very nice a lot more simple than i imagined . You have me tempted and i like how you discharge capacitors very wise .Only problem my drives wont handle that voltage and i am loath to spend any more money on this thing until it brings a bit back in .
You prob aware of this company https://vacuumtables.co.uk/t-slot-plates they do T slot beds i may go for the 20mm ali one if all goes well .
I had a look at G wizard they do a 30 day trial but may save that till after Christmas as got a job on nest week then its hols
You wouldn't mind running these three cutters through G wizard would you for ali cutting to keep me going over next few days

6mm 2 flute https://www.cutwel.co.uk/milling/millin ... 522-series

10mm 2 flute https://www.cutwel.co.uk/milling-tools/ ... d71-series

3mm 1 flute https://www.cutwel.co.uk/milling/millin ... e47-series

Just doing spiral profiles nothing clever 50mm circle

No worries if busy but hopefully you might have already done these


Author:  DISPLACEMENT 1 [ Fri Dec 15, 2017 4:48 am ]
Post subject:  Re: CNC Router Build

Ps sorry i didn't see your first post my attention was grabbed by your lovely transformer :D

Author:  edward [ Fri Dec 15, 2017 5:22 am ]
Post subject:  Re: CNC Router Build

OK, this is what it says at 50% which is what I normally use, it's just a rough idea anyway

6mm 2 flute at 10000revs 700mm/min

10mm 2 flute at 10000revs 1180mm/min

3mm 1 flute at 10000revs 200mm/min and 3mm 1 flute at 16000revs 316mm/min

Obviously things change at other speeds, but for high revs you will need lub, so I would stick to 10000 or lower if possible.

As for the transformer, yes, there is no point until you change drivers that tale the higher voltage, will do a video of my combo with just one stepper later, see what revs I can get.

Author:  DISPLACEMENT 1 [ Fri Dec 15, 2017 6:13 am ]
Post subject:  Re: CNC Router Build

When you say 50% is that half diameter of cutter for depth of cut ? Eg 6mm cutter 3mm depth of cut ?
Cutters haven't turned up yet so stuck in post Cutwel usually very good oh hum!
As for power supply i am planning to build another camera rig eventually ( remember thats how all this started ) So that would be good for that i am sure you will get some quite hi speed torque things out of it
Cheers thanks for the speeds D1

Author:  edward [ Fri Dec 15, 2017 6:25 am ]
Post subject:  Re: CNC Router Build

G-Wizard has a slider that controls how rough or how fine you want to cut and calculates accordingly.

50% is in between rough and fine, usually a slightly conservative setting, a good starting point.

Author:  DISPLACEMENT 1 [ Fri Dec 15, 2017 6:39 am ]
Post subject:  Re: CNC Router Build

Ah i see will give G wizard a test in new year . Do you think its a good buy ?
If it saves me monye snapping and gumming cutters i suppose it is .
Think will go for a 1mm depth of cut on the 6mm and see what happens :?

Page 9 of 12 All times are UTC - 8 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group