Does this answer one of your your questions about VFD?
http://www.mycncuk.com/threads/4985-...spindle-wiring
About the last question i believe this can do the job :
https://www.aliexpress.com/item/3278...27424c4d4NkJmR
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Does this answer one of your your questions about VFD?
http://www.mycncuk.com/threads/4985-...spindle-wiring
About the last question i believe this can do the job :
https://www.aliexpress.com/item/3278...27424c4d4NkJmR
Perfect, ThanksQuote:
Originally Posted by Doddy
Quote:
Originally Posted by Nickhofen
Cheers Nick!
Little more progress on the Z axis - managed to mill the channels required for the Z ballscrew yesterday. Bridgeport wasn't trammed perfectly, so the surface is a little off, (I was under quite strict time constraints and the tramming worm screw is broken - so its as good as I could get without it) but it will certainly do the job I need it to. Assembled the Z axis for a test-fit late last night, but forgot to take pictures, so they'll follow.
Attachment 25930Attachment 25931Attachment 25932Attachment 25933Attachment 25934
My monster of an electrical cabinet has also arrived... 800x600x300 is massive, but should fit everything!! Went for the glazed door option, although unfortunately it has some dings in the door - I'm guessing its just a grey hammerite paint touchup job.
Attachment 25929
I know I promised frame photos.... but I'm still halfway through painting the bed, and I'm not massively pleased with my 'smooth' hammerite finish. Despite our best efforts, the paint ran all over the place and whilst the surface is smooth, the light clearly reflects the brush strokes. :/ Any advice appreciated!
I use paint rollers to paint my bed,the painting is faster and easier to applied this way .
If you see lines this means that you have to thinner the paint , when the paint is thinner is leveled when applied, but be careful not to use too much thinner.
Thanks Nick, what do you use to thin it? How much?
Test assembly of the Z axis with obligatory drill movement test (although I can rotate the screw by hand):
Attachment 25935Attachment 25936Attachment 25937Attachment 25938
You have to use the exact thinner type that the company suggest,about how much you will find it on the color container. I usually start with less thinner than the amount the company suggest,then try the thinned paint on a surface with the paint roller and let it seat for about ten minutes .
If it is not transparent and the color is leveled it self,I mean you do not see marks after ten minutes,you can do your job, with the roller you might notice small bubbles in the color,it is ok those are going to disappear when the color cures
If the paint is sticky add thinner, shake well before use!
Make one thick pass and do not repaint after some minutes or hours , because the new paint will dilute the old one and you will end up with a mess....
Good luck!
Thanks Nick, the thinners and your advice has really helped. I've recoated it, and although it's still not removed the paint brush lines and the surface is nowhere near perfect, it's improved a lot. I think ultimately, I'll need to take the frame back to bare metal to fix this mess, but then again, it's just looks - the metal is protected as is, so I'm going to forge on regardless.
Also been cleaning up a few of the Z axis components now they're complete, ready for final assembly when I got the surface plate out.
In other news, put my slightly dented but massive cabinet up on the wall... Used a spirit level on the edges... The damn thing is a rombus!! The door is extra wonkey to boot... Serves me right for buying a cheaper cabinet I suppose...
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Attachment 25979
Next steps...
The current challenge on the base frame front is the epoxy framing and pour - I've sourced the MDF side pieces and cut to size, time to start gluing and siliconing!
On the gantry front, my next challenge is the motor mounts (thats the only thing, besides no belts, stopping me driving the Z and Y with motors).
And on the electronics front, I'm currently sourcing cables and components for the cabinet... its all go!
Visited the science museum yesterday, saw this and it made me smile and think of you lot:
Attachment 25997
But the smile has faded, because today, I've been tackling the demon that is E-P-O-X-Y. Unfortunately, I don't think its gone too well, but I'm going to let it do its thing for two weeks, then if needs be chip it off and start all over.
So, first off, I started by levelling the base frame on its levelling feet. Turns out my longest spirit level has an error in it, and I wasted a good half hour chasing the damn thing until I figured out it changed when rotated 180 degrees. Oops. Trusty digital spirit level to the rescue, which was much easier to flip round every time.
Once my lovely smooth and flat steel beam was level, I then set about mauling it with the grinder. The idea was to give the epoxy something better to stick on to.
Attachment 25998 Attachment 25999
We then assembled the epoxy frame. This seemed to go really well - the only thing i'd change would be the width of those spacers you see over the top of the frame - it was quite a pain in the arse getting below them on the later stages. Take special note of the blue bottle we purchased to do the epoxy pour with - it has a tap on the other side which we thought would be ideal. We then started heating the garage up, got the air temp up to about 28 dungarees, and whilst we were doing this we taped the bottom edge of the epoxy frame, and then used silicone sealant all the way around on both the inside and outside faces (we really don't want any epoxy leaks). We also clamped the frame down onto the bed before doing this.
Attachment 26000Attachment 26001Attachment 26002
After letting all that silicone set, and a bloody-good chineese takeaway, we set about the epoxying. We measured out and mixed the 1.3L in six equal sets by weight, taking a minute to thoroughly stir after each set. Naturally I got the wife to do this, as she is an expert stirrer.... When we got to the end, we did a two minute stir, then thought it would be a really good idea to let it sit for 10mins to let the bubbles rise out. It was going really really well - the bubbles were rising to the surface nicely, away from our little tap....
Attachment 26003
Cue minute eight. The tub starts to look a little strange. Cries of "Oh Shit! The pots melting!!" come from the other side of the garage as the tub starts imploding and the epoxy level rapidly rises towards the rim of the bottle. Thankfully, we already had our gloves on and at the ready, so taking the very hot bottle, I swing it over to the frame and start the first pour by hammering on the tap's release button....
Of course, the damn thing had already jammed shut. At this point, theres nothing for it but to up-end the bottle and start pouring from the top. Bubbles are being created everywhere, and there are a lot of fumes being released into my unsuspecting garage. I think they were mostly melting plastic fumes... but they could also have been fumes from the rapidly curing quatermass.
Somehow, we managed to get the epoxy poured (taking shifts on who could hold their breath in the toxic air for the longest, the other running outside for some palatable air). I managed to go round 3/4 of the frame with a scribe and poke a few of the biggest bubbles before it became too gelled to continue, but most of them have left small craters. I'm quite sure the last 10cm or so hasn't been able to level before gelling.
Heres the good bit (that was poured first and attended to) - We then decided to coat everything but the bridge in clingfilm, so that nothing can fall into it, and then we retreated putting the mangled bottle in the emergency bucket.
Attachment 26004Attachment 26005Attachment 26006
Videos of the final result to follow....
Hi Andy,already sent you a pm about what may happened,and here is the answer from west system site:https://www.westsystem.com/instructi...oxy-chemistry/
Controlling Epoxy’s Cure Time
In warm conditions use a slower epoxy hardener, if possible. Mix smaller batches that can be used up quickly, or pour the epoxy mixture into a container with greater surface area (a roller pan, for example), thereby allowing exothermic heat to dissipate and extending open time. The sooner the mixture is transferred or applied (after thorough mixing), the more of the mixture’s useful open time will be available for coating, lay-up or assembly.
Thanks to both Scustom and routercnc, think you have both nailed it, the combination of waiting for bubbles, and mixing in a tall narrow container allowed the exothermic reaction to spiral out of control.
I've got a new set of Epoxy on order, I've spent the evening clearing off the crap pour and the mountain of silicone, and will try again soon. Thankfully the frame hasn't suffered and can be used again with a fresh set of silicone. Expensive mistake but hey, we all screw stuff up every now and again!
This time, I'm going to make the amount in three mixes rather than 6, and in a wider tub. I'll then transfer to another jug with a taped up hole in the bottom, and immediately pour onto the rails.
Sent from my SM-G950F using Tapatalk
Living near Southampton has some advantages - fast epoxy delivery!
Poured again tonight, and fingers crossed, I think we've nailed it.
We mixed in a very wide tub - an old decking screws container. Did the entire 1.3L in one go, adding 175g 105 and 50g alternatively, mixing a little inbetween. The mixup process took about 6.5mins start to finish, then did another final mix for 1.5min until no streaks were visible and the colour was entirely uniform. We then transferred to a 2L ice-cream tub which had two 8mm holes in the side at the bottom corner taped over (we measured the flow time of 0.5L of water through a 5mm hole, and decided it needed to be 8mm. Found about 20seconds for water through 8mm - so decided that should be a nice 1-2min pour of the epoxy which worked well. Second hole was a backup and never used.
The pour went really well - managed to time it so that the fizzy bubbles at the end of the tub landed in the centre of the bridge. Surface looks glassy smooth - had two 1-2mm bubbles on the main beams, but managed to easily pop them with a scribe. There are some very small <0.5mm bubbles in the epoxy itself throughout - but I'm not too worried about these as they're so small.
Weather looks good for the week, not dipping below 14 degrees, and the garage was 23 degrees when we poured. I haven't used any artificial heating yet - the plan is to poke the bridge section on Sunday, and if its still not gelled, we'll start heating then.
Thanks for the help everyone... fingers crossed!!
Attachment 26010Attachment 26011Attachment 26012
Lets talk cabinet layout for a moment or two.
I've just started a thread about tidy wiring (here) so I'm currently still deciding how to do my wiring channels (shown as green in the annotated diagram) as neatly as possible, but I think I've got a plan for the overall layout.
Attachment 26184 Attachment 26185
As you can see, I've silently been buying more and more electronical bits (psst... please don't tell the wife how much this stuff costs...). My plan is to have the drives vertical in the bottom right with heatsinks facing each other, right by the inlet fan. The outlet fan will then be at the top of the case directly above the VFD (or possibly top left facing out sideways... which might be better from a water point of view if the roof were to leak (a real possibility in my garage...). My thinking here is that they'll have the most urgent cooling need in the cabinet, so they get the coldest air first. I'll probably put the two X drives at the top, as they'll be working the hardest and I don't want their heat transferring to the Y and Z drives - Who knows if that logic makes any sense or not? Maybe it should even be the other way around...
This position allows the driver outputs to get straight out through the GX20 connections on the base, and the input signals can come directly in from the right hand edge (as shown) of the UB1 where all the step and direction signals come from. The drive PSU is a little awkward here, but shouldn't be too far for the power to get to the drives from the right hand side of the PSU.
The GX16 connections (limit switches, homing switches etc) also come in at the bottom and can go straight up to the UB1.
My plan is for mains to come in bottom left, skirt behind or up the side of the PSU, and into the distribution/fuses area. From there each mains device will connect via individual EMF filters and relays/contactors/big on off switch as required.
Finally, theres a low voltage section up top. My plan for this is to have the safety / 24V circuits up here. This is where the control panel will interface - I have a selection of LED buttons for this, each with a specific function in mind, but I still haven't decided exactly where the panel will go (having a glass fronted cabinet is nice, but not so many options for things like buttons!).
Anyhow, I hope that either this post is helpful to others, or someone can point out any glaring problems or things I've not thought about! Update on the mechanicals soon - there is currently paint drying, and the garage has been even messier than usual in the last few weeks so I've not gotten around to photographing and writing up the most recent developments.
I promised an update on the frame - here she is in all her badly painted glory!!
Since the last photos, I've
- Faired the edge of the epoxy into the frame and repainted the box sections.
- Filed off the meniscus along the edges and at the ends.
- Marked drilled and tapped the epoxy for the rails.
- Roughly aligned the rails for parallelism
- Checked the levelling with a precision straight edge - more details below.
- Thrown the gantry on the rails - it glides super smooth (and made me very happy!)
- After getting happy about that, I then got very sad. Turns out my steel frame is a bit of a rhombus! When I bring the gantry to one edge, it hits the end of one rail about 3-5mm before the end of the other, and the opposite occurs at the other end. I don' t think this will actually affect anything, except perhaps my pride...
- I then did some more milling, making my Z and Y nema 23 motor mounts. That was fun. :)
- Did a rough assembly - All I need now to make the Z and Y axis move under their own power are the belts which are on order. It was nice to be able to measure the distances between pulley centres physically rather than just in CAD.
The rails both show the same trend, they're high at the ends and low in the middle with an error of about 0.05mm - I'm sure this could be better, the epoxy still set relatively quickly, so I'm sure there are improvements to make. It could be that I just haven't filed down the ends of the epoxy enough and they're slightly propped up at the ends, but its 'close enough' for me at this stage. The other consideration is that this value is the stated accuracy of my straight edge, so optimising it now seems counter productive. I will probably come back and shim the rails, but I'm keen to do a 'proof of concept' and am aiming to have the machine cut something by Christmas.
I've noticed that the Z axis isn't as smooth as the others; I think it might be the alignment of the ballscrew vs the rails, I've discovered that my design is a bit of a nightmare to try and measure the alignment between the two, because the rails and the screw are attached to different parts. The other thing it might be is that the Z axis is the only one thats had a load of EP2 applied - does that typically increase the resistance on the screw? I can turn the pully by hand no problem, but you can feel that it has more and less resistance at different ends of the travel, which is something I don't feel on the Y. Any hints or tips?
The other problem I'm now considering is how to check the axis are perpendicular... can anyone point me in the right direction? I think Boyan mentioned needing two precision squares to align properly... I can see why you'd need one, but two?
Thanks!
Attachment 26212
Attachment 26216
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Attachment 26215
If the diagonals of the x (long axis ) are equal, then the axis is orthogonal,start from this !
Then bring the Y axis at a point and measure with a square, that you know it is at true angle.
How you know that you square is really a square?
Check this video:
https://m.youtube.com/watch?v=gDh-E5xhm0o
If your square is not as it should ,do not through it away,check on YouTube how you can make it square again.
Good luck!
And remember any precision tool that is fall on the ground or it it is banged on something hard,stops to be a precise any more,it needs re calibration.
Hello. Looks really good! Is there any benefit if looking a how rigid the machine is by having the gantry rails on top and at the bottom, compared to mounting both on the same side?Quote:
Originally Posted by AndyUK
For example if we compare these 5 options, which one is the best for rigidity?
- Both rails on the spindle motor side of the gantry, ballscrew in between rails.
- Both rails on one spindle motor side of the gantry, ballscrew in between on the opposite side.
- One rail on the spindle motor side side, ballscrew on the same side and the other rail on the top of the gantry.
- One rail on the top, one at the bottom and the ballscrew on the opposite side of the spindle motor side.
- One rail on the top, one at the bottom and the ballscrew on the same side as the spindle motor side.
See the Beginner Moving Gantry Design ThreadQuote:
Originally Posted by NordicCnc
Thanks for that link!
By the way do yiu have a youtube chabbel? I saw a very similar if not the exact same build. Joe Harris is the name of the channel.
Skickat från min SM-A530F via Tapatalk
Hi Andy. Didn't see an answer to your question about VFD harmonics. I fitted an emi filter from the mains to the input of my control box using one of these https://www.ebay.co.uk/itm/EMI-RFI-F...edirect=mobile . This plus star farthing all the shielded cabling eliminates the problem I had when the vfd was running (false estops). Also mounted my vfd external to the controller again to avoid electrical noise getting through.
Hi MikeyC,Quote:
Originally Posted by MikeyC38
Thanks for the tips! I bought three of those from Ali Express a while back; I chose three because I placed them after the mains input and before each main component (VFD, 24V PSU, and Drive PSU) - hopefully so that noise from each didn't affect the other, because it had two filters to pass through, if that makes any sense. When it came to wiring them though, I realised the IEC cable wasn't what I wanted (being that theres three inside the cabinet), so I got some alternatives with spade connectors on. Something like this.
Yep - If you look at the start of this thread, you'll see its heavily based on Joe's build. I'm a bit more camera-shy though, so haven't gotten on the old youtube.Quote:
Originally Posted by NordicCnc
In other news, I'm slowly but surely wiring away. Taking a little time over it - life has become rather busy at the moment with all the other distractions :) I'll try and post a picture of current progress sometime this week.
Thanks,
Andy
Hi Andy. That's a very nice layout on your machine - it's certainly strong enough to handle aluminium. Grats on the build JanBo
Heya All,
Promised an update, so here we go!
Wiring is in progress in the living room - oh my life there are a lot of wires on these things. Trying to keep it as neat as possible, but certainly not an easy task. Slightly concerned about how close the UC300eth is to the VFD; but it leaves room for a mini ITX sized PC in the future if I want to move in that direction, or a fifth motor driver for a forth axis.
Attachment 26641
I've also been designing my gland plate - the plan is to have it detachable from the inside (as well as the outside) so the plate can be taken out with the entire electronics panel for reworking in the future if required. To do that, my plan is to put a stainless steel plate on top of the current gland plate. Apparently I took the layout photo the opposite way around though!
Attachment 26642
Attachment 26643
In other news, my X Axis ballscrews are on and connected - the aluminium stand-offs for the ballscrew mounts are temporary, but they are the correct thickness. There's a certain aspect of 'I'll make that better later once its working' going on here... ;)
Attachment 26644
Attachment 26645
I've also ordered an aluminium block to try out water-cooling those motors inside the frame. Hopefully it should fit right in, and do the job nicely - but we shall see. My next job on the mechanicals is to make the X axis motor mounts, but that needs another day on the old bridgeport.
I can see why everyone posts a video when they get their E-Stop circuits working for the first time :) Its quite a nice amount of clicking and clunking going on.
Until you decide to leave the panel running for five minutes with the motor driver supplies latched in.
And then you smell smoke.
And realise that the 24V contactor you purchased has the confusing symbols "50/60Hz" following the 24V designation...
Oh well. Off to find myself a new 24VDC contactor... ;)
That video may have to wait - although I can attest to the fact that if the contactor short circuits, the PILZ will cut the power to it pretty sharpish.
Hi Andy
If it makes you feel any better I did exactly the same thing,
Whoops..
Haha it does! Thankyou :)
In all seriousness, hopefully by sharing the woopsie moments I can prevent someone else doing the same in the future. This is my first time purchasing and specing out these types of components, and on the rapid electronics page and datasheet there is only a single line which alludes to the fact it's an AC coil; "for AC switching" which I took as "for switching AC loads" - I've never seen 24VAC used for control circuitry before, but clearly it's the default.
+1 I did the exact same thing on my build too!! [emoji85]Quote:
Originally Posted by AndyUK
Sent from my SM-G920F using Tapatalk
Andy, you're showing your age (or lack of it:tennis:) 24v AC dates back to when control systems were relay based (eg the 1960's Marconi BD272 250kW radio transmitter). AC is better for 'wetting' relay contacts and obviously does away with the expense of a rectifier and smoothing.Quote:
Originally Posted by AndyUK
Kit (aka Old Fart)
Haha - well, I'm glad I'm not the only one. It has prevented me smoking my other relays, which were also 24VAC... and I've managed to find a replacement 24VDC contactor at work which was for a machine we removed a long time ago and otherwise going to waste.
I was born before the Berlin wall fell, but not by much - so I'll have to take your word on the 60s! :)
Now that the contactor is working as expected I can share my E-Stop circuit video as promised! I appreciate its the same as everyone elses, but hey, its a progress milestone. I also couldn't resist playing with the LED switches - the Red is E-Stop reset, the Green is the motor drive power latch, and the Blue are auxiliary switches for water pump/air solenoid. There will also be a yellow momentary limit OVR, but I haven't gotten around to installing that one yet. The plan is to have a control panel on the front of the machine rather than at the electronics box - so at the moment everything is wired up to these terminals at the top of the plate, and then I'll take them to the panel with a couple of 7-core CY cables.
https://youtu.be/3QmBGxghq9s
I've also got the signals for the motor drivers wired in, and I've connected up the Z axis motor just to test the communication with UCCNC, so theres a video of that in the mix as well - enjoy! You'll see the Y and X drivers instantly fault out - the UC300 is reading those fault signals, however they're currently configured the wrong way around (I'm waiting for my RJ11 crimper to reprogram the drivers). The fault signal wiring has changed somewhat from my last published schematic; my plan is to use the OSSD on the UB1 to enable or disable the drives, so that a fault signal on one drive causes all of them to stop - but again I need to program the drives to listen to the enable line.
https://youtu.be/U-uzLlwuTG4
The proximity switch has also been tested, although my trial one was an NC 2mm NPN - 2mm is a bit small, so I'm planning to try a 4mm next. I'll probably use proximity switches for both limits and homing, but thats still up for debate.
Looking good. It's nice when things start to move.
I've just finished mine. Just running a few codes through it not cutting anything to see if it gets any false stops.
It doesn't look like you will be long before it starts moving it's self.
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I was born before the Berlin wall was built, but not by much, so whilst I saw the 60's I didn't learn about their control systems until the 80's.Quote:
Originally Posted by AndyUK
Nice work on the controller. Yours is much neater than mine!
Kit
Andy have you post a wiring somewhere for your control box?
If you're after the wiring diagram, there is an early version in post #37 (page 4 for me). It needs some updates though - most notably it needs 2k resistors on the enable + lines else it's a good way to blow the EM806, and it doesn't have the UC300 disabling the drives through the OSSD because this is new for me and still needs testing.
My plan is to update the diagram and post soon :)
Awesome,thanks.
I am struggling to find time to continue with my build and it is very helpful to have a wiring to start with.
Here's the current version of the circuit diagram - don't take it as gospel, check every connection against the datasheet of both things you're connecting as you go (that's how I realized before it was too late that +24V to the drives on the enable without the 2k resistor was a bad idea). I haven't made all these connections yet, so that's why I'm warning everyone!
Attachment 26682
Having said that - let me know when you find a mistake ;)
Andy, quick question - the schematic suggests the 4x2k resistors are commoned, unless you mean to draw a bus supply (yellow line to EN inputs on the drivers) - is that correct?
I'd also protect the LED indicators from back emf from the relay coils - LEDs don't take reverse polarity well (unless these or the relays already have protection?)
Thanks Doddy -
I'm being very economical with my lines - the resistors arn't commoned at all - I'm just trying to say that it doesn't matter which line goes into which input, and I didn't have room to draw them all individually, however I'm constantly rejigging it so will try and fix that for clarity.
I don't think the LEDs are protected - good point. Is that just a diode across the LED in the opposite direction to allow the back EMF to flow past it? Haven't wired those relays yet - they're on order (as the initial ones were 24VAC).
Edit - Diagram updated above.
Understood about economy of lines, I’d originally interpreted the schematic a described but there’s other examples of 1:1 mapping which was enough to ask the question.
Led protection?, what you describe is perfectly good. I’d have thought to suppress directly across the coil but across the led works as well
Good point about the diode protection from back emf, I have placed mine directly on the relay to protect the coil from back emf.
What do I miss about the resistors on the enble+ line? I mean obviously the resistors will reduce the current flow but how much is the current that will run if the resistor is not there and how much is acceptable?
I have the AM882 that is why I am asking!
Attachment 26684
The AM882 has the same logic signal current specifications as the EM806 (hardly surprising considering they're basically the same thing, but I thought I'd check). 7-16mA with a nominal of 10mA. They've designed it for a 5V signal, so I expect the internal resistance is ~500 Ohms (because that's what gives 10mA for 5V). V=IR, so I = 24V / 2.5kOhm = 9.6mA. (I used 2.5kOhm because my 2k resistor plus 0.5k internal).Quote:
Originally Posted by Nickhofen
Or, you can just read the diagram in the driver's manual about the connection where it specifies in a small box below that you need to add a 2kOhm resistor if the signal is 24V, which is a far simpler way to do it!
We don't need the resistors on any of the other lines - The pulse and direction outputs from the UB1 are 5V signals, and the alarm signal is an output not an input, so it has different specifications.
Looking at limit and home switch placement... I've kinda put this off as long as possible, but here goes.
The idea is to use proximity switches for both - and to use two travelling switches on Z and Y, then 3 fixed switches on each X axis.
Unfortunately because I've only thought about these late in the game, they're a bit shoe-horned in - I'd appreciate any comments or suggestions... I feel like I've tried about a million different placements.
I remember reading somewhere that proximity switches should be triggered by a sloped target - I'm not sure if I've got my targets sloped in the right direction, or even what angle to aim for.... Some advice would be awesome!
Zoomed Out for Reference:
Attachment 26716
Attachment 26717
Z Axis:
Attachment 26711
Y Axis Limit
Attachment 26712
Y Axis Home + Limit
Attachment 26713
X Axis Limit
Attachment 26714
X Axis Home + Limit
Attachment 26715
I've also posted a few wiring questions over on CNCRoom - my hope was that they'd be able to help more with the UB1 specifics, but seems to be drawing a blank so-far. If anyones interested, the post is here: https://www.cnczone.com/forums/uccnc...92066-cnc.html