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View Full Version : BUILD LOG: New build - Steel - 3 Axis initially then conversion to 4 axis.



Slixxor
13-06-2016, 12:12 PM
Hi guys,

Dave here. I'm designing a new machine for the office in the hopes of carving precision rifle stocks (4 axis) and whatever else is required from hardwood and aluminium. :)

The build is already underway and frame currently ready to be painted.

Details of the build
==============

Linear bearings: SBR20 fully supported rails - X:1300mm - Y:1000mm - Z:450mm
Ball screws: RM2005 Chinese - X:1350mm - Y:1050mm - Z:500mm
Steppers: Nema23 - 23HS45-4204S
Drivers: M542H
PSU: 48V 600w DC

Frame/Chassis: 65x65x3mm box steel
X axis chassis: 75x75x4mm box steel
Gantry cross beam: 200x100x5mm box steel
Gantry supports: 300x125x10mm steel angle
Z axis supports: 200x480x10mm steel plate

Contrary to most builds on here I do not have a CAD diagram to show as the build is a running design at present. I have very little CAD skills unlike my wife, who regularly makes designs in Solidworks.

Here's some pics of the current build:

original design
18672

Adjustible feet
18671

Front on view - all level within ~1mm
18673

Side view
18674

Z axis setup.
18675

Gantry side on.
18676

Anyway, thought i'd share guys. let me know what you think. :)

- Dave.

routercnc
14-06-2016, 06:57 AM
Looking good so far Dave.
Any reason for the 2005 ballscrews? The 1605/1610 are more popular because they have lower inertia which helps with the acceleration and deceleration, especially on the modest 48V you are using.

Slixxor
15-06-2016, 01:41 AM
Looking good so far Dave.
Any reason for the 2005 ballscrews? The 1605/1610 are more popular because they have lower inertia which helps with the acceleration and deceleration, especially on the modest 48V you are using.

I havent purchased the PSU yet. so may go larger. the motors claim to have a max voltage of 48v. i can get a 60V no troubles but am not sure of the impact that would have on the steppers. As far as the RM2005's goes, i was aiming for a rigid setup for cutting aluminium and didnt want any wobble from ball screws. Feed rate isnt that critical for me.

Clive S
15-06-2016, 07:43 AM
I havent purchased the PSU yet. so may go larger. the motors claim to have a max voltage of 48v. i can get a 60V no troubles but am not sure of the impact that would have on the steppers. As far as the RM2005's goes, i was aiming for a rigid setup for cutting aluminium and didnt want any wobble from ball screws. Feed rate isnt that critical for me.I wouldn't be worried about the steppers but the drives in your spec you have said that you are using these M542H If I am not mistaken the max voltage they will handle is 50V so 48V would be too high for them. AM882 drives would be a better choice running at about 68-70 V.

If you want a decent machine you have to have decent electronics.

Slixxor
15-06-2016, 08:30 AM
I wouldn't be worried about the steppers but the drives in your spec you have said that you are using these M542H If I am not mistaken the max voltage they will handle is 50V so 48V would be too high for them. AM882 drives would be a better choice running at about 68-70 V.

If you want a decent machine you have to have decent electronics.

Ok, it's now being considered. :) havent bought the drivers yet either. you are right indeed, my voltage restriction was the M542H. price is only AU $20 more per driver.

Clive S
15-06-2016, 08:47 AM
Ok, it's now being considered. :) havent bought the drivers yet either. you are right indeed, my voltage restriction was the M542H. price is only AU $20 more per driver.Ok then if you have not bought the motors either then try and find 8 wire so they can be connected in parallel and get the lowest inductance motors you can find these are proved and tested by many over here :- http://cnc4you.co.uk/resources/Stepper%20Motor%20Nema%2023%2060BYGH301B%203.1Nm.p df.

Good luck with the build.

Slixxor
15-06-2016, 09:03 AM
Ok then if you have not bought the motors either then try and find 8 wire so they can be connected in parallel and get the lowest inductance motors you can find these are proved and tested by many over here :- http://cnc4you.co.uk/resources/Stepper%20Motor%20Nema%2023%2060BYGH301B%203.1Nm.p df.

Good luck with the build.


I have the motors already and all mounting hardware. saving the electronics for last. The AM882's are in the price range. I am running dual ballscrews on the X Axis. so additonal cost. but oh well :)

mekanik
15-06-2016, 09:15 AM
You can run both X axis screws with one motor and belt connecting them,it's common practice with the guys on the forum.
Good luck
Mike

Slixxor
15-06-2016, 11:29 AM
You can run both X axis screws with one motor and belt connecting them,it's common practice with the guys on the forum.
Good luck
Mike


I have noticed that. but whats the go with custom belts? Obviously each machine will differ in length required. Do you simply ask for a particular length?

mekanik
15-06-2016, 12:10 PM
You can get custom belts but they are more expensive, but you have a lot of leeway length wise as you will have adjustment on the motor and your tension/routing belt layout. there was a post on the forum a while ago showing a belt routing setup to address this issue.
Regards
Mike

Slixxor
15-06-2016, 03:21 PM
Ok. Z AXIS design time. What is the acceptable leverage ratio of a sturdy Z?

My length of linear rail is 450mm. I was hoping for 300mm
Of cutting depth but it seems like there would be excessive difficulty keeping my Z cutting straight with a 150mm (1/3 ratio) binding area for the spindle on a 450mm run. What do you all suggest?

Also, would be wiser to mount the linesr bearings on the spindle plate or on the gantry plate?

Electroconducive
15-06-2016, 03:58 PM
Rails on the spindle plate. To make a variable lever. Bearing blocks spaced at 50% of z travel and as wide as possible.

I'll let the resident experts correct me if I am wrong. I'm still drawing up my design. However, this is my understanding.

Slixxor
18-06-2016, 05:53 AM
X and Y axis bolted and mounted. Was a very tight fit on the Y axis bearing blocks but It fits like a glove :)

18733

18734

Slixxor
29-06-2016, 03:43 AM
Few more updates. a redesign of the Z axis and some major work to keep it all straight. moves very smoothly now. Z axis is 6mm steel. working on the ball screws next.

Here's a quick vid of the movement: https://youtu.be/DRLe3EPQ01M

Here's some photos.
188051880618807188081880918810188111881218813

Slixxor
07-08-2016, 12:30 PM
OK, so progress has been slow but i've finalized and purchased the electronics.

PSU's: 70v 5.7A Switchmode PSU.

Drivers: 2MA860H.

Motors:


Manufacturer Part Number
23HS45-4204S


Step Angle
1.8°


Holding Torque
3.0Nm(425oz.in)


Rated Current/phase
4.2A


Phase Resistance
0.9ohms


Recommended Voltage
24-48V


Inductance
3.8mH±20%(1KHz)


Weight
1.8kg




Thanks to CliveS and the others on suggesting not buying a kit.

More to come shortly. there have been some more changes :)

Slixxor
20-12-2016, 09:49 AM
Z Axis finally fitted and relatively smooth with motion (No racking), Some filler welds will be done in the coming days and the wiring should be done shortly. :) I'm finally starting to see it all come together. I wasn't really sure if my Z design would work, but it seems extremely rigid. Although I've lost 100mm of travel on the Y axis I've maintained a good center of gravity on the Z axis and increased the X axis work area.

Hopefully cutting in January!

200492005020051

Tom J
26-12-2016, 11:47 PM
Nice concept of Z axis, only problem is that doesn't allow for any adjustment other than shims. How smooth it travels up and down?
Asking as I machined similar stuff on chinese mill and wasn't parallel.
Same thing for entire machine - you are mounting rails directly to profiles - no machined base, no epoxy for leveling (parallel, squareness?)
I do not criticize you - just wander if you aim for accuracy in your machine.

Slixxor
27-12-2016, 01:11 AM
Nice concept of Z axis, only problem is that doesn't allow for any adjustment other than shims. How smooth it travels up and down?
Asking as I machined similar stuff on chinese mill and wasn't parallel.
Same thing for entire machine - you are mounting rails directly to profiles - no machined base, no epoxy for leveling (parallel, squareness?)
I do not criticize you - just wander if you aim for accuracy in your machine.
Pretty smoothly. I do have a video of it turning by hand..

https://youtu.be/lEZzJ3c4UJA

I think the reason for the success in motion is the heating of various sections during the fabrication process.

I like working with steel because it warps and moves when heated.

When designing the Z most of the welding occured on Job with clamps. As the steel heats and warps it smoothly contours around its pressure points. I.e: the fasteners on the bearing blocks and the tension applied by the SBR25 rail.

Not to mention meticulous time spent hammering the fudge out of it at times :) the outer walls were hardest. They have a slight warp in the 6mm and needed lots of bashing and even driving the car over it.

Cutting a square for the ballscrew bracket was the best idea. As it allowed me to drill it then weld it back in with just the tension of the ballscrew to warp to.

There really was no other way though. Accessing the correct drill points would have been almost impossible to get right as it was completely blind.

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Tom J
27-12-2016, 01:23 AM
Pretty smoothly. I do have a video of it turning by hand..

https://youtu.be/lEZzJ3c4UJA

I think the reason for the success in motion is the heating of various sections during the fabrication process.

I like working with steel because it warps and moves when heated.

When designing the Z most of the welding occured on Job with clamps. As the steel heats and warps it smoothly contours around its pressure points. I.e: the fasteners on the bearing blocks and the tension applied by the SBR25 rail.

Not to mention meticulous time spent hammering the fudge out of it at times :) the outer walls were hardest. They have a slight warp in the 6mm and needed lots of bashing and even driving the car over it.

Cutting a square for the ballscrew bracket was the best idea. As it allowed me to drill it then weld it back in with just the tension of the ballscrew to warp to.

There really was no other way though. Accessing the correct drill points would have been almost impossible to get right as it was completely blind.

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My first bed was ok till I weld those flat bars 8mm thick - it warp badly in the middle
2009620097

Slixxor
27-12-2016, 10:23 AM
My first bed was ok till I weld those flat bars 8mm thick - it warp badly in the middle
2009620097
Looking goid mate! Tack welds are the way to go. And lots of clamping. I would have got a piece of say 35x70mm box tube and clamped it in several places to the flat bar piece you were working on. Then going from the outsides in to the middle as your box frame will also slightly warp from the welds. Tack everything first then repeat the clamping process all over again with your filler welds.

It's hard with long runs like that. Partly the reason bojan S uses C channel for his bed. Although I find welding much easier, drilling and bolting would have given a better result.

Whats the link for your thread?

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JAZZCNC
27-12-2016, 12:00 PM
Good job your using round rails because wouldn't get away with rough work like this if using Profiled linear rails.!!

Tom is correct your level of accuracy will be low or will require lot of shimming and tweaking. How much will only come to light when finished and being used at which point you'll wished you'd took little more care when building.:thumbdown:

Tom J
27-12-2016, 12:11 PM
Looking goid mate! Tack welds are the way to go. And lots of clamping. I would have got a piece of say 35x70mm box tube and clamped it in several places to the flat bar piece you were working on. Then going from the outsides in to the middle as your box frame will also slightly warp from the welds. Tack everything first then repeat the clamping process all over again with your filler welds.

It's hard with long runs like that. Partly the reason bojan S uses C channel for his bed. Although I find welding much easier, drilling and bolting would have given a better result.

Whats the link for your thread?

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Here is my latest build
http://www.mycncuk.com/threads/9073-Desktop-size-steel-welded-router-3-axis
Small work area but was aiming for accuracy. Box 100x100 end up with ~0.07mm that is why i build again fixed gantry one, link:
http://www.mycncuk.com/threads/10459-Desktop-type-router-Fixed-gantry-steel-frame-MK2
Boyan is master in precision fallow him - he gets 0.02mm wich is more than my chinese mill

JAZZCNC
27-12-2016, 12:18 PM
Boyan is master in precision fallow him - he gets 0.02mm wich is more than my chinese mill

Ye and I'm father Xmas.!!

Tom J
27-12-2016, 12:26 PM
Looking goid mate! Tack welds are the way to go. And lots of clamping. I would have got a piece of say 35x70mm box tube and clamped it in several places to the flat bar piece you were working on. Then going from the outsides in to the middle as your box frame will also slightly warp from the welds. Tack everything first then repeat the clamping process all over again with your filler welds.

It's hard with long runs like that. Partly the reason bojan S uses C channel for his bed. Although I find welding much easier, drilling and bolting would have given a better result.

Whats the link for your thread?

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My frame was not more than 1mm warp as I tack it everything and weld one bead at the time, cool down and opposite side and so on. I have to admit that I broke my rule and did not let to cool enough (firstly was warp corners down than after cool opposite) - £100+ waste on steel and gas, lesson learnt. I bit it with sledge hammer, driven by the car and finally filled down, so my 8mm bars became 4mm in places:)
Now I use Tig just to see if I can do better
2009820099

Slixxor
27-12-2016, 12:33 PM
Good job your using round rails because wouldn't get away with rough work like this if using Profiled linear rails.!!

Tom is correct your level of accuracy will be low or will require lot of shimming and tweaking. How much will only come to light when finished and being used at which point you'll wished you'd took little more care when building.[emoji107]
Haha savage feedback. Thanks Jazzy, time will tell.

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JAZZCNC
27-12-2016, 02:29 PM
Haha savage feedback. Thanks Jazzy, time will tell.

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I could blow smoke up your arse but still won't make it any better when cutting time arrives.:encouragement:

Tom J
27-12-2016, 02:35 PM
Ye and I'm father Xmas.!!

do not be jealous Dean, results speaks itself. And on the end of the he takes your advises like we all do:)

JAZZCNC
27-12-2016, 02:57 PM
do not be jealous Dean, results speaks itself. And on the end of the he takes your advises like we all do:)

I'm not into jealousy but I am realist and know there's no way he's measuring 0.02mm over 3000mm like he's claimed in the past or even over shorter distance.!! . . . Ask me why.?

Ok I'll tell you.!! . . . . . Would be bloody impossible because he's using C7 ballscrews From China which at best will only give 0.05mm over 300mm. Then throw in few belts/pulleys etc and this goes down further.

So who's fooling who.?

Slixxor
27-12-2016, 04:49 PM
I could blow smoke up your arse but still won't make it any better when cutting time arrives.:encouragement:
I just like the way you assumed I needed to be more careful. What exactly gives you the impression I haven't been?

Hence the reason I will see how it goes when it's done. I've endeavoured to make it as square as possible on all axes and feel comfortable that I've managed to achieve that within the best of my ability.

I'll be sure to let you know if you're right or wrong once it's done and I tweak everything :)

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Slixxor
27-12-2016, 04:52 PM
I'm not into jealousy but I am realist and know there's no way he's measuring 0.02mm over 3000mm like he's claimed in the past or even over shorter distance.!! . . . Ask me why.?

Ok I'll tell you.!! . . . . . Would be bloody impossible because he's using C7 ballscrews From China which at best will only give 0.05mm over 300mm. Then throw in few belts/pulleys etc and this goes down further.

So who's fooling who.?
When did I make that claim? This is my first build and I don't see that claim made :/? I think you grossly underestimate my realism.. [emoji14]

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Slixxor
27-12-2016, 04:56 PM
My frame was not more than 1mm warp as I tack it everything and weld one bead at the time, cool down and opposite side and so on. I have to admit that I broke my rule and did not let to cool enough (firstly was warp corners down than after cool opposite) - £100+ waste on steel and gas, lesson learnt. I bit it with sledge hammer, driven by the car and finally filled down, so my 8mm bars became 4mm in places:)
Now I use Tig just to see if I can do better
2009820099
TIG will give a better result but will still warp. Either way it can be a pickle when working with steel. I still haven't decided what bed to go with on mine. I will probably do MDF to start with.

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JAZZCNC
27-12-2016, 05:15 PM
When did I make that claim? This is my first build and I don't see that claim made :/? I think you grossly underestimate my realism.. [emoji14]

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Crossed purposes wasn't talking about you with that statement.


I just like the way you assumed I needed to be more careful. What exactly gives you the impression I haven't been?

Because I'm not blind and can see there's been no machine work done on any of those surfaces or any thought regards rails being on same plane etc.
I've never yet seen piece of angle iron that is perfectly flat or 90deg and you are bolting straight to the face of one.

Then we have the heat put into the metal which can clearly be seen. You can Stitch it with pigeon Shit and beat the shite out of it all you like but it will still be warped or twisted in some way unless you take other steps to correct it.

All these little things will bite and like I've said your lucky your using round rail. Profiled linear rail would just not tolerate this level of in accuracy and bind up solid.

Edit: Just to be anal and prove my point look at this picture and tell me whats wrong.?

20107

Clive S
27-12-2016, 05:16 PM
When did I make that claim? This is my first build and I don't see that claim made :/? I think you grossly underestimate my realism.. [emoji14]

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If you read it again Dean was not referring to you with the above It was a claim made by another on the forum.


Hence the reason I will see how it goes when it's done. I've endeavoured to make it as square as possible on all axes and feel comfortable that I've managed to achieve that within the best of my ability.At the end of the day that is all anybody can do. Looking forward to seeing the first cut :friendly_wink:

Slixxor
28-12-2016, 12:29 AM
You sir have a much better personality. I think JAZZCNC needs a holiday by the sounds.. Clive, legend as always ;)

Slixxor
28-12-2016, 12:31 AM
Crossed purposes wasn't talking about you with that statement.



Because I'm not blind and can see there's been no machine work done on any of those surfaces or any thought regards rails being on same plane etc.
I've never yet seen piece of angle iron that is perfectly flat or 90deg and you are bolting straight to the face of one.

Then we have the heat put into the metal which can clearly be seen. You can Stitch it with pigeon Shit and beat the shite out of it all you like but it will still be warped or twisted in some way unless you take other steps to correct it.

All these little things will bite and like I've said your lucky your using round rail. Profiled linear rail would just not tolerate this level of in accuracy and bind up solid.

Edit: Just to be anal and prove my point look at this picture and tell me whats wrong.?

20107

You are referring to me shaping it? I don't see the problem? what are you suggesting? (genuinely asking)

spluppit
28-12-2016, 01:52 AM
Having a good read of this thread I'm rather speechless and even more speechless with the commentary that goes with your posts Slixxor, you can educate yourself so well on the internet of the basics it' just takes a bit of time to learn and absorb. I'm not going to pick up on individual things because would be here until the 1st of January. This is not a good advert for someone to have a go at home. You are one brave man to post this publicly.

Slixxor
28-12-2016, 02:49 AM
Having a good read of this thread I'm rather speechless and even more speechless with the commentary that goes with your posts Slixxor, you can educate yourself so well on the internet of the basics it' just takes a bit of time to learn and absorb. I'm not going to pick up on individual things because would be here until the 1st of January. This is not a good advert for someone to have a go at home. You are one brave man to post this publicly.
Im confused what bewilders you? Can you elaborate? I dont see how my build is different to any other. And my comments are far from offensive. Do you just not like the design. Im confused

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routercnc
28-12-2016, 09:00 AM
In post #32 the Z bearings are trapped between the fixed distance between the angle iron sections. This means they cannot sit naturally, or have any pre-load control, and you can't adjust it either.

I'm guessing you welded it together with the angle iron bolted to the bearings? If you release the bolts into the Z bearings do they slide out easily from under the Z axis (which is what you want), or does the Z axis 'spring away' or 'close up'? Ideally this should be a nice gentle fit onto the bearings , or possibly have a slight bit of pre-load.

Slixxor
28-12-2016, 09:24 AM
In post #32 the Z bearings are trapped between the fixed distance between the angle iron sections. This means they cannot sit naturally, or have any pre-load control, and you can't adjust it either.

I'm guessing you welded it together with the angle iron bolted to the bearings? If you release the bolts into the Z bearings do they slide out easily from under the Z axis (which is what you want), or does the Z axis 'spring away' or 'close up'? Ideally this should be a nice gentle fit onto the bearings , or possibly have a slight bit of pre-load.
When welded they werent bolted on. Just the outer frame clamped onto both sides with pressure applied. When loosened there is slight rubbing on the bearing blocks but minimal force is required to remove them. If on an angle they scrape and fall straight out. The bearing holes were drilled afterwards with bearing blocks on the rails with no tension. The rear of the bearings were coated with steel blue and the top casing was slid over the bearing blocks creating the guide for my bearing block drilling die I'd made.


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JAZZCNC
28-12-2016, 10:44 AM
You sir have a much better personality. I think JAZZCNC needs a holiday by the sounds.. Clive, legend as always ;)

Oh so your YES man well tough luck because if it's shit you'll get told it's shit by me.! . . . . Like wise if it's good I'll say so as well but I see nothing here that's good.!

To be fair I've been very kind on what I've commented so far, mainly because not got full week spare to list all that's bad.!


You are referring to me shaping it? I don't see the problem? what are you suggesting? (genuinely asking)

Nothing to do with shaping and every thing to do with being warped and surfaces not on same plane. Then generally just weak poor rough arsed engineering which for CNC won't cut it.
Just because your using steel doesn't mean it's stronger. If the design is weak and poorly built which this is then doesn't matter if built from 2" steel material or 0.1" aluminum (note Ref in American just to so can understand . .lol) you'll never succeed in achieving accuracy or reliabilty.

Look again at this Pic for just few bits of whats wrong.!

20111

Slixxor
28-12-2016, 10:55 AM
Oh so your YES man well tough luck because if it's shit you'll get told it's shit by me.! . . . . Like wise if it's good I'll say so as well but I see nothing here that's good.!

To be fair I've been very kind on what I've commented so far, mainly because not got full week spare to list all that's bad.!



Nothing to do with shaping and every thing to do with being warped and surfaces not on same plane. Then generally just weak poor rough arsed engineering which for CNC won't cut it.
Just because your using steel doesn't mean it's stronger. If the design is weak and poorly built which this is then doesn't matter if built from 2" steel material or 0.1" aluminum (note Ref in American just to so can understand . .lol) you'll never succeed in achieving accuracy or reliabilty.

Look again at this Pic for just few bits of whats wrong.!

20111
I dont see how that section is relevant to the outer edge. It is on the inside of that weld?

Considering you sound a bit jaded and have really offered no constructive advice whatsoever (which I find strange from a person who appears to be a guru on this site.) I would appreciate it for mine and the others sake not commenting just saying "this is bad.. all bad.. but I wont say why cause the list is too long and my bollocks are itchy. Whinge whinge" If it's so bad, dont comment OR do as the wise do and wait until I say "whoops, made a mistake." Then pipe up accordingly.

Anyway, I'm sure that in ever experienced CNC loving life of yours you can stifle your vomit long enough to calmy ask questions and then make assumptions.

Sincerely, non American but in fact Australian novice CNC builder. :)

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njhussey
28-12-2016, 11:45 AM
Hi Dave,

I think what most people are going on about here is that you've used flat and angle without any sort of machining (not that I've seen mention of in your thread?) to make the surfaces true to either themselves or mating surfaces. Angle (as I'm sure you knowand have found out) is nearly always under or over 90° and the surface is never flat, certainly not the inner surface where you've mounted your Z axis bearings. This will lead to binding (your video unfortunately shows or proves nothing about how smooth the Z axis is just that you can turn the ballscrew and it moves, sorry) and premature wear of the bearings which will lead to a sloppy Z axis and inaccuracy. Jazz is being harsh (but perfectly fair) in his remarks, it's the way he is and he tells it like it is without any BS, he is one of (if not the) the most helpful and knowledgeable people on this forum and his comments are worth listening to, even if you don't like them.

If you'd welded your Z axis and then had it machined so the bearing blocks could sit square, flat and true, and had the ballscrew mounting section machined flat/square and where the spindle is going to mount machined square to everything else then all this would be immaterial, but there's no way in hell that all this is going to be square with just plain welded steel. Yes you'll be able to use the machine but at what accuracy (you may not need much accuracy so this is all immaterial) and how long before the bearings wear and it all become loose and sloppy? The spindle will require lots of shimming to get it perpendicular but if your rails aren't straight/parallel and true then it'll still not cut accurately. How have you trammed the rails so they're parallel to each other, what equipment do you have (DTI's, levels, straight edges etc.) to check for straightness, parallelness etc?

Whatever the outcome good luck with your build and I'm looking forward to seeing the first chips coming off this :eagerness:

Slixxor
28-12-2016, 01:05 PM
Hi Dave,

I think what most people are going on about here is that you've used flat and angle without any sort of machining (not that I've seen mention of in your thread?) to make the surfaces true to either themselves or mating surfaces. Angle (as I'm sure you knowand have found out) is nearly always under or over 90° and the surface is never flat, certainly not the inner surface where you've mounted your Z axis bearings. This will lead to binding (your video unfortunately shows or proves nothing about how smooth the Z axis is just that you can turn the ballscrew and it moves, sorry) and premature wear of the bearings which will lead to a sloppy Z axis and inaccuracy. Jazz is being harsh (but perfectly fair) in his remarks, it's the way he is and he tells it like it is without any BS, he is one of (if not the) the most helpful and knowledgeable people on this forum and his comments are worth listening to, even if you don't like them.

If you'd welded your Z axis and then had it machined so the bearing blocks could sit square, flat and true, and had the ballscrew mounting section machined flat/square and where the spindle is going to mount machined square to everything else then all this would be immaterial, but there's no way in hell that all this is going to be square with just plain welded steel. Yes you'll be able to use the machine but at what accuracy (you may not need much accuracy so this is all immaterial) and how long before the bearings wear and it all become loose and sloppy? The spindle will require lots of shimming to get it perpendicular but if your rails aren't straight/parallel and true then it'll still not cut accurately. How have you trammed the rails so they're parallel to each other, what equipment do you have (DTI's, levels, straight edges etc.) to check for straightness, parallelness etc?

Whatever the outcome good luck with your build and I'm looking forward to seeing the first chips coming off this :eagerness:
Hi mate,

Thanks for the feedback. My measuring equipment consists of various levels, squares, straight edges rulers and a vernier caliper.

I had considered the wear on the bearings and have endeavoured to set them as true as practical. Initially I screwed the middles in one spot of the rails then used the ballscrew brackets motion to guide it back and forward and held each side of the rails in place with rare earth magnets to get my parralell edges. Also the magnets edges set the line for squareness.

I did need to reweld the old screwholes on 1 side and redrill new ones parralell to the other fully fastened side as it was quite a 'tough' fit and felt like there was more pressure towards the lower end when extending it. I've actually never spent this much time on one welding job ever. With more than 40 hours just in the Z axis alone. There is infact a tapering 0.8mm shim on the right side to get it so slick it wants to skate off in a breeze.

As far as accuracy goes. If I can cut a rifle stock to my 3D design and all it needs is light sanding then I'm happy. I've been doing them by hand so far and getting one side the same as the other is near impossible. Also, spending 6 hours with a dremel digging the action channel is not fun.

I don't have an issue with negative feedback, I just find it pointless and offensive when I see random posts that say "lucky you used round rail, profile rail wouldn't let you do that.". As I myself are not into BS, The pointless comparison between round rail and profile rail is unnecessary and not helpful.


P.S I am taking full advantage of my round rails. I'm well aware that I can use the radial axes for giving me some room to play. :)

Sent from my SM-G920I using Tapatalk

JAZZCNC
28-12-2016, 04:12 PM
Anyway, I'm sure that in ever experienced CNC loving life of yours you can stifle your vomit long enough to calmy ask questions and then make assumptions.

Sincerely, non American but in fact Australian novice CNC builder. :)

Argh your aussie I missed that and do apologise but should have known as it makes sense now.!! . . . Arrogant bastard.!

Has for the rest there's been no assuming on my part because like I said before it's plane to see, even if you can't. Sorry if you think I'm being unhelpful but others did try but your Arrogant attitude wouldn't listen so thought maybe shock tactics would work better.? I would have gone onto the helpful stuff but to grant your wish I'll keep my unhelp self from offering any advise. However I will still chip in if needed just for the sake of others so they don't make same mistakes.!!

G'day Mate.!!

Slixxor
29-12-2016, 01:57 AM
Argh your aussie I missed that and do apologise but should have known as it makes sense now.!! . . . Arrogant bastard.!

Has for the rest there's been no assuming on my part because like I said before it's plane to see, even if you can't. Sorry if you think I'm being unhelpful but others did try but your Arrogant attitude wouldn't listen so thought maybe shock tactics would work better.? I would have gone onto the helpful stuff but to grant your wish I'll keep my unhelp self from offering any advise. However I will still chip in if needed just for the sake of others so they don't make same mistakes.!!

G'day Mate.!!

friendly enough for me... you can Stay JAZZCNC :)