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DIY CNC Milling Machine From Scratch
Hello everyone, well after making my first router type cnc machine on a budget ive decided to push the boat out and make a milling machine based of a sieg x3 machine.
The machine is going to be a bit larger than an x3 and hopefully far more rigid.
linear rails on all axis
DQ860MA 80V Drivers
yet to decide on powersupply
3.0Nm on X and Y nema 23
4.5Nm on z nema 34
2.2kw spindle to start with and hopefully BT30 spindle with ATC in the future.
Pictures to follow:
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Re: DIY CNC Milling Machine From Scratch
Hopefully this is what it will look like: Nearly fully Drawnhttp://img.tapatalk.com/d/14/06/26/zu7yde6y.jpg
Ears welded up to support the z axis
http://img.tapatalk.com/d/14/06/26/epy4u4a9.jpg
Z axis sides, 20mm thick:
http://img.tapatalk.com/d/14/06/26/husu9y2u.jpg
The z axis fully built ready to be surface ground:
http://img.tapatalk.com/d/14/06/26/nyzamede.jpg
Surface ground and holes drilled and tapped for the ears:
http://img.tapatalk.com/d/14/06/26/beneme2u.jpg
Just checking the squareness: looks pretty good although this is adjustable on final assembly:
http://img.tapatalk.com/d/14/06/26/6eza8are.jpg
Mock up:
http://img.tapatalk.com/d/14/06/26/8e6u8e7y.jpg
Steps machined for linear rails and ball screw supports and nut:
http://img.tapatalk.com/d/14/06/26/ryma9ezy.jpg
All holes drilled for linear rails, ball screw supports and the screws which will push them towards the parallel edges:
http://img.tapatalk.com/d/14/06/26/une7ehad.jpg
Y axis plate machined and holes drilled ready to mount the rails and then surface ground:
http://img.tapatalk.com/d/14/06/26/umu2e8y5.jpg
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Re: DIY CNC Milling Machine From Scratch
This is just a test piece to check how well the taper locks up: was pretty good with just letting it drop in under its own weight, it would stay in when held upside down, and with a tap of a mallet i wasn't able to pull it apart by hand :)
http://img.tapatalk.com/d/14/06/26/hu9ubehu.jpg
http://img.tapatalk.com/d/14/06/26/aradupa3.jpg
Adjustable gas strut to help with the weight of the heavy z axis:
http://img.tapatalk.com/d/14/06/26/y4a8ege3.jpg
That's all for now apart from the rails and ball screws that everyone has seen before, material for the bed has been ordered and hopefully will be starting this soon :)
Hopefully everyone likes the build so far!
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Re: DIY CNC Milling Machine From Scratch
Very nice and definitely will be following this build.
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Re: DIY CNC Milling Machine From Scratch
There I was at lunch time today browsing through google images at other peoples mill type builds (shortly after reading through JBs x3 conversion thread), i'm keen to have a go at my own mill type, is it obvious yet?
Then I jump on tonight and I find this gem of a thread! Yea! Perfect timing, cant wait for the rest totts !?!
.Me
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Re: DIY CNC Milling Machine From Scratch
Starting to look very purposeful. Well done. G.
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Re: DIY CNC Milling Machine From Scratch
Thankyou, lots still to do, everytime i think about it theres more to do! :(
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
totts
Thankyou, lots still to do, everytime i think about it theres more to do! :(
Hehe always the way, are you going to fill the z axis column with anything to help with resonance or do you plan for something else, what are you going to use for the base of the machine, my thoughts are a nice slab of steel?
.Me
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DIY CNC Milling Machine From Scratch
I have a nice solid slab of aluminium as shown in the drawing, about 500mm x700mm by 76mm thick so i hope this will be solid enough.
I was going to fit some of the electronics into the colomn but i am now going to make a stand to house the spindle cooler, electronics, pc and coolant pump, so will probably think about filling the column with something after the z stepper and y stepper is mounted so i know where to fill.
Trouble is the cost keeps mounting up :( best not to take note and hide the reciepts from the missus hahah
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Re: DIY CNC Milling Machine From Scratch
Good start - almost getting jealous!
A few general observations...
Have you seen the BT30 ATC spindles on Aliexpress? If you're happy with 6000rpm then they're not excessively expensive:
http://www.aliexpress.com/wholesale?...initiative_id=
PSU - why no decision? A toroidal transformer of around 500VA would be ideal.
What is the mass of the Z-axis (head, spindle etc) and what are the dimensions of the Z-axis ballscrew? I've made a script to calculate it more accurately, so if you post that information we can make sure the motor you've chosen is the best option. I suspect you may be OK with one of the 3-4Nm Nema 24 motors. The gas strut makes surprisingly little difference if you try to get a reasonable acceleration...
Correct me if I'm wrong, but it looks like you're leaving the back of the Z column open, so it's a C-shape section not a box? If so then you should defiantly put another plate on the back, as the torsional stiffness of a C-section is very low compared to a box. That's one of the big advantages of putting the ballscrew on the front of the column, not inside - you can have a closed section.
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Quote:
Originally Posted by
Jonathan
Good start - almost getting jealous!
Correct me if I'm wrong, but it looks like you're leaving the back of the Z column open, so it's a C-shape section not a box? If so then you should defiantly put another plate on the back, as the torsional stiffness of a C-section is very low compared to a box. That's one of the big advantages of putting the ballscrew on the front of the column, not inside - you can have a closed section.
Dito!, Jonathan if he was to close the back up and opt for a box, would it be of worth while benefit to also add some ribs inside the box, I was thinking towards cantilever, an X in a square, the through sections on each plate would also allow then for the filling of the column?
Quote:
Originally Posted by
totts
I have a nice solid slab of aluminium as shown in the drawing, about 500mm x700mm by 76mm thick so i hope this will be solid enough.
I was going to fit some of the electronics into the colomn but i am now going to make a stand to house the spindle cooler, electronics, pc and coolant pump, so will probably think about filling the column with something after the z stepper and y stepper is mounted so i know where to fill.
Trouble is the cost keeps mounting up :( best not to take note and hide the reciepts from the missus hahah
Sounds like it would be.
I think its fair to say that making it a box and filling it would be of more benefit to the machine.
Hehe, what's new :encouragement:.
.Me
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Re: DIY CNC Milling Machine From Scratch
Hmmm yeh true i will add a back the column now, but im not sure on the ribs as if i weld these it may upset my ground face, i may add a couple bars inside to act like rebar. I will get some info on the z axis as im not sure weather to make them out of steel or ally for acceleration.
Ballscrews are 1605 on all axis.
Toroidal transformer is the way i am going for now, just need to do some research.
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Re: DIY CNC Milling Machine From Scratch
A bit more work done tonight, the beginning of the bed. This is the main body where steel strips will sit creating the t slots, coolant channels on either side. This will eventually be ground.
http://img.tapatalk.com/d/14/06/27/y7e2y6yg.jpg
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
totts
Hmmm yeh true i will add a back the column now, but im not sure on the ribs as if i weld these it may upset my ground face, i may add a couple bars inside to act like rebar.
I don't think adding more than the plate to the back of the column will make much difference, as it's the least stiff parts of the machine you need to target if trying to make it stronger. Intuitively I'd say that's a different part, but hard to say without modelling it, which takes a long time...
Quote:
Originally Posted by
totts
I will get some info on the z axis as im not sure weather to make them out of steel or ally for acceleration.
Yes please do. The difference in torque required from using aluminium vs steel is unlikely to be significant, plus steel has better damping properties so I'd prefer steel. Although as Lee has pointed out, there are other ways to solve the damping problem.
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
Jonathan
I don't think adding more than the plate to the back of the column will make much difference, as it's the least stiff parts of the machine you need to target if trying to make it stronger. Intuitively I'd say that's a different part, but hard to say without modelling it, which takes a long time...
Not quite sure what you mean there? Would it be a good idea to add a plate to the back of the column and fill it with resin, or concrete?
Steel it is then! Cheaper too! Does anyone know the realistic weight of a 2.2kw spindle?
I will hopefully be goin to have a bt30 cartridge and motor, but i suppose it wont be too difficult to change the stepper motor of needed in the future.
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
totts
Not quite sure what you mean there? Would it be a good idea to add a plate to the back of the column and fill it with resin, or concrete?
Steel it is then! Cheaper too! Does anyone know the realistic weight of a 2.2kw spindle?
I will hopefully be goin to have a bt30 cartridge and motor, but i suppose it wont be too difficult to change the stepper motor of needed in the future.
He’s talking in terms of adding strength to the machine and he’s right but I was really referring to eliminating resonance more than anything, I can’t see that adding ribs/reinforcing plates wouldn’t add extra strength to the column, I think they would help towards stopping any twist in the column at the very least.
I think the problem with concrete is that it’s relatively brittle (though I note your suggestion of using rebar), cracks could form in the concrete and over time it may break down inside the column, I don’t know enough but I’m guessing that it doesn’t really have the same dampening properties as other materials, epoxy resin is a favourite but so is kiln dried sand and the sand is cheaper in comparison.
I think what I will do with mine is to, reinforce the column on the inside, use a mix of aggregate (different sizes, type 2, pea shingle and so on) to then fill the column, then backfill the lot with epoxy resin (filling up the leftover voids) all the way to the top, hopefully creating one solid mass. The idea being the aggregate is just away to use less resin (cost vs. cost) but also brings back the properties of using sand.
.Me
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Re: DIY CNC Milling Machine From Scratch
Right okay i see now, i think the plan will be to enclose the section in the back which isnt being used by the stepper motors, and fill it with sand, i can always use a resin afterwards if i change my mind.
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
totts
Right okay i see now, i think the plan will be to enclose the section in the back which isnt being used by the stepper motors, and fill it with sand, i can always use a resin afterwards if i change my mind.
Exactly, you could run some tests to see the difference with and without sand, you may not even need any.
.Me
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Re: DIY CNC Milling Machine From Scratch
Back to work with my column to drill more holes haha. The bloody thing is heavy hahah!
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DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
Jonathan
What is the mass of the Z-axis (head, spindle etc) and what are the dimensions of the Z-axis ballscrew? I've made a script to calculate it more accurately, so if you post that information we can make sure the motor you've chosen is the best option. I suspect you may be OK with one of the 3-4Nm Nema 24 motors. The gas strut makes surprisingly little difference if you try to get a reasonable acceleration...
Okay after managing to get on the computer i have made sure my plates are made of steel, and from what i can find the 2.2kw spindle is around 5.15kgs then the z axis is around 45kgs.
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Re: DIY CNC Milling Machine From Scratch
its an impressive build so far totts,wheres the adjustable gas strut from and whats it rated at?thanks
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DIY CNC Milling Machine From Scratch
http://www.strutsdirect.co.uk/produc...-sd03-400-p-76
Their postage is a little high but not to badly priced.
They come in many lengths n sizes, mines adjustable set at 1200N but will release the pressure when everything is assembled.
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Re: DIY CNC Milling Machine From Scratch
not bad at all,thanks a lot,
keen to see this mill in action.,i did toy with making my own for a while then bottled it and bought an sx3.
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DIY CNC Milling Machine From Scratch
Yeah i came very close to getting an sx3, axminster had a 10% off all machines, and when i went on the website they had been reduced due to discontinuing them, and could have picked a new one up for £800!
Only thing that stopped me is the need for a slightly bigger travel and higher spindle speeds.
Have you a video of your sx3 in action?
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
totts
Have you a video of your sx3 in action?
no not yet I bought it new from arc a while back and immediately ripped it aprt and fitted ball screws and steppers.(wishing I put profile rail on it after seeing what you and jonathan are upto..upgrade for the future maybe)at the minute im on the wiring so a week or two away yet.
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Re: DIY CNC Milling Machine From Scratch
Will be very interested to see it running! Yeah profile rail is bloody exspensive tho :(
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Re: DIY CNC Milling Machine From Scratch
Got some steel strips made up now ready to be bolted onto the bed, just waiting for some stainless steel countersunk screws to turn up!
http://img.tapatalk.com/d/14/07/03/anugazyd.jpg
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Re: DIY CNC Milling Machine From Scratch
I would be very carfull filling anything like that with that much epoxy and when it cures it can produce a huge amount of heat and contained in a metal tube you could have a small disaster on your hands. If you do want to do this make sure it is extremely slow curing and if anything put some bags of ice around it to keep the heat down and only do a little at a time.
Quote:
Originally Posted by
Lee Roberts
He’s talking in terms of adding strength to the machine and he’s right but I was really referring to eliminating resonance more than anything, I can’t see that adding ribs/reinforcing plates wouldn’t add extra strength to the column, I think they would help towards stopping any twist in the column at the very least.
I think the problem with concrete is that it’s relatively brittle (though I note your suggestion of using rebar), cracks could form in the concrete and over time it may break down inside the column, I don’t know enough but I’m guessing that it doesn’t really have the same dampening properties as other materials, epoxy resin is a favourite but so is kiln dried sand and the sand is cheaper in comparison.
I think what I will do with mine is to, reinforce the column on the inside, use a mix of aggregate (different sizes, type 2, pea shingle and so on) to then fill the column, then backfill the lot with epoxy resin (filling up the leftover voids) all the way to the top, hopefully creating one solid mass. The idea being the aggregate is just away to use less resin (cost vs. cost) but also brings back the properties of using sand.
.Me
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
charlieuk
I would be very carfull filling anything like that with that much epoxy and when it cures it can produce a huge amount of heat and contained in a metal tube you could have a small disaster on your hands. If you do want to do this make sure it is extremely slow curing and if anything put some bags of ice around it to keep the heat down and only do a little at a time.
Thanks for the heads up Charlie, is it really that bad?
.Me
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
Lee Roberts
Thanks for the heads up Charlie, is it really that bad?
.Me
depends exactly on the epoxy but yes especially in warm temps, if you left a cup of epoxy to cure on its own you would be surprised how much smoke it can make! its a exothermic reaction so when if heat starts to build its a chain reaction and just gets hotter and hotter and will quickly turn into a smoking and bubbling mess. Ive never had flames but have heard of it. It all so doesn't make any different if you have some sort of filler mixed in with the epoxy so less actual resin to fill the space it will still have the same effect. As i said small quantities a bit at a time in a cold temp is your safest bet.
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Re: DIY CNC Milling Machine From Scratch
Blimey i knew it could get warm but not that hot! I think ill start with the sand!
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Re: DIY CNC Milling Machine From Scratch
Had a talk today about dampening and have thought of shot blast(cast iron type) mixed with kiln dried sand?
Also a bit more progress....
http://img.tapatalk.com/d/14/07/05/2ygade7a.jpg
Ground and Ready to machine the slots on the top, and the steps on the underside of the bed.
Once the rails have been bolted to the bottom it will be ground again to ensure the top is parrallel to the rails.
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Re: DIY CNC Milling Machine From Scratch
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DIY CNC Milling Machine From Scratch
A few things, just been busy at work :( done a few parts but not interesting tho, just added a plate to the back of the z axis and made a few home switch mounts, got a few bits of aluminium and steel box section delivered, so hopefully will be able to start the stand, and start building :). Oh and have managed to start painting a few bits!
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Re: DIY CNC Milling Machine From Scratch
Quote:
Originally Posted by
charlieuk
depends exactly on the epoxy but yes especially in warm temps, if you left a cup of epoxy to cure on its own you would be surprised how much smoke it can make! its a exothermic reaction so when if heat starts to build its a chain reaction and just gets hotter and hotter and will quickly turn into a smoking and bubbling mess. Ive never had flames but have heard of it. It all so doesn't make any different if you have some sort of filler mixed in with the epoxy so less actual resin to fill the space it will still have the same effect. As i said small quantities a bit at a time in a cold temp is your safest bet.
You don't want to fill it with just epoxy, as that won't dampen anything. You want an epoxy-sand mix, with ~10-15% epoxy. You need a thin, slow setting epoxy to get enough working time. The sand will keep it from getting hot.
I've mixed up a cup of epoxy sand, and it doesn't get hot at all. A cup of plain epoxy, on the other hand, will exotherm and get very hot in only a few minutes.
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Re: DIY CNC Milling Machine From Scratch
Few more things finally done after holidays, and a very busy couple of months at work!
Have designed and made the steek stand for the machine
http://tapatalk.imageshack.com/v2/14...fa260e70ee.jpg
Have roped in my dad to make the electronics cabinet!!
Steel frame has been welded up and will hopefully have a lick of paint this weekend!
Have also managed to make one of two plates which connects the x and y axis together...
http://tapatalk.imageshack.com/v2/14...18abf89b32.jpg
Hopefully will be able to make the other tomorrow,
Soon be able to start putting things together :)
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Re: DIY CNC Milling Machine From Scratch
Stand needs some diagonal bracing or will flex/resonate under load. Ideally the electronics box should be steel not wood to provide safety earth and interference reduction.
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Re: DIY CNC Milling Machine From Scratch
The stand is merely there to make up the height, or would it still resonate? Will get to it at the weekend!
Yeh thats what i was thinking last night! May have to re think that one!
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Re: DIY CNC Milling Machine From Scratch
You'll be surprised how much movement gets transmitted to the base, especially if the mill is cnc. If purely manual it's less of an issue. My mill was on a wooden stand but wasn't cnc. Even so, starting the spindle with a large boring head or fly cutter caused noticeable movement as no soft start.
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Re: DIY CNC Milling Machine From Scratch
Irving is spot and the more ridged the better. I mostly build CNC routers not mills and often they go into sheds sat on bench's. My standard reply is this machines going to rock this shed and often the standard reply is a laugh thinking I'm joking.!! . . I'm not.!!
Can't tell you the number of times I've got emails within a day or saying "Your right last night I ran a job fast and the whole shed rocked". . Lol . . . . . Even had some one drive the gantry thru the shed wall. .Lol
CNC and the fast directional changes will easily rock a weak frame out of alignment or to bits etc or across the room if not fastened down.
Regards the electronics then I'm not a fan of fastening the box directly to a vibrating machine or it's frame but sometimes need must.!