How to use Ubuntu - Klang Malaysia

[KenC]

This Z-slide is fashioned around Irfan's design. I merely maximize the spacing between the linear slides & the rails to make use of the available space. The total Rail length is 495mm since the only come in 1 meter length. I suppose the effective Z-axis strove would be 285mm max. which is more then necessary (for now), but no harm having

Thanks Irfan for sharing!

[jehayes]

Re: post #240

Or playing poker!

[javeria]

you are welcome ken!

I use a grease gun with normal auto bearing grease in it. also it would be interesting to see the rack mounted and the mounting of your motor, have you had enough place for the springs?

I have added two spring and need to adjust their lengths to get them the right length,

and a warning for the tapped holes in the Alu plate- sooner or later they will give up,

I had my spindle plate threads (thread on the tightening bolts) give up on me today, will spend tomorrow 2 hrs fixing that.

[KenC]

Irfan, thanks for the heads up.

I dry fitted the motor & gear rack, even without the spring, there seems to have enough space for the springs.

As for spring length, I bought a turnbuckle for it.

I used 1.25mm pitch threads on Al rather then 1mm. I hope they will hold up better.

Al tends to have that problem, I normally use coarser threads then what we do on steel but they as they are softer, they will go eventually. You can use HeliCoil insert for the repair, once the HeliCoil is in place, it can take the wear & tear much better.

[KenC]

A few more pix

All in position for checking clearance
Z-slide Assembled 1.jpg

The turnbuckle without the spring
Z-slide Assembled 2.jpg

Another view
Z-slide Assembled 3.jpg

Looks like unobstructed for now.
Z-slide Assembled 4.jpg

Had to grind a fair bit of the motor mounting plate to clear the car body & slide mounting screw head.
Z-slide Assembled 5.jpg


The slide & spindle weight at 15kg total, consider there will be a kg or 2 with the addition of dust collector feet, I'll order a 15kg gas spring with 250mm stroke.

[cab. guy]

Ken ,I'm in the process of building a 4Th axis stand alone machine with linear guides.
This time I am privileged to use my first cnc to machine the keyways for the linear guides.First, aluminum plate is flatter than aluminum bar.If you take a straight edge
on the face of your rails ,one to another ,you should have no more than .005 tolerance out of plane.Like wise there should be no more than 005 tolerance in the parallel form.Having met these two qualifiers,you are indeed within tolerance.Yes ,there is much more push resistance.The secret in the industry is using
a minimal amount of lube on these guides giving you much more longevity.

[KenC]

Ron, thanks for sharing.
Yes, even with a single unrestricted carriage, some push force is required, so I don't expect the slide to glide effortlessly smooth as our X-gantry & Y-car

I managed to get the rail level within .005 using filler gauge. but parallel only to 0.01mm over 490mm. All this accuracy is useless as eventually getting a smooth motion boils down to the alignment of the carriage. which the only method I know is to tighten each carriage gradually & pushing the carriages + back plate assembly on the rail one bolt at a time & one carriage at a time.... painstakingly slow, & demand a cool head.

I also did a crude test with a spring weight & learn that the static pull force of about ~8kg to set it in motion & about ~6kg to keep on moving. Is this normal?

Please pardon my ignorant, from my understanding of things (which is not a lot... ), other then lubrication function, the grease also serve to fill the void within the carriage to "expel" & "ward away" the potential foreign particles "invader" while the seals act as the "castle wall" to hold off foreign particles out. In the case of MM wood dust predominant environment, the wood dust will absorb any form of liquid/moisture & stick to anything including the rail. which makes grease in pasty form such as automobile lube grease the lubricant of choice. but as you said minimal amount of lube gives longevity is mind boggling. Please do elaborate. I do wish to learn more on this.

Thanks in advance.

[cab. guy]

HI Ken,The accuracy on the rails .005 is an inch ,yes? The .01 is also an inch? You appear to have Hiwin 25mms. mounted on aluminum bar.The rolling resistance sounds about right,20lbs or so. You could take the mean average of a single guide
resistive pull weight ,multiplied by 4 ,as it relates to alignment resistance?Every setup
will have a different resistance,based on size,brand and style.Now that I think about
it just put all 4 guides on the same rail ,and weight the train.Its probably fine,another option that would be fairly simple,Jury rig the machine together (operational),mill your own plates,dead on ,no more guess work.This latter option I would feel more comfortable with.You create key ways about 1.5mm deep.One 25mm rail is the master
rail ,it gets a 25mm width cut, the other rail is the slave rail with 25mm+ .01mm alignment slop.You first screw the master rail down,leaving the slave rail float,now put your assembly together ,slide it up and down,this will dictate the ideal screw positions for the slave rail.This is only 1/2 the sandwich,the other 1/2 would involve
machining in the guides 1.5mm with key ways that are exact---no slop. Ken you do not sound ignorant about grease.I am not a licensed bearing proctologist. My source came from two individuals that I personally know as being highly competent stated basically the same thing.What they found from their experience was that,weather linear guides were in a clean room or
in a dirty industrial areas,one thing in common,employees ignore maintenance,yet the
guides were in operation for years.On the other hand if you pack grease in,that grease goes directly on the rails,becoming massive debris magnets.The seals and scrapers do work for the most part,what you will notice,the screw caps themselves hold small debris that the seals cannot get at,thus providing access to guide cavity.
If the rails are kept clean and debris dry and expanded the seals knock it right off the rail.In your case its a non issue as your rails are vertically positioned--very little dust.

[KenC]

Ron, thanks for elaborating.
My measurements are in metrics so they are 0.05 (0.002") & 0.1mm(0.004") Its great comfort knowing my slides are normal and my tolerances are ok. Really shred the burden.
I did almost exactly as you posted, only different was I had the rail keys milled by a machine shop. which should fall within 0.01mm accuracy in both parallelism, height & slope but there is a 0.4mm difference between the height (ok with the parallelism & slope) which I rectified by shimming the slide carriage, moreover, there is a variance of about 0.1 between the 2 carriages on the same rail & I shimmed that as well.
The mounting procedure was
1)find the carriage that is highest, tighten the carriage to the plate,
2)measure the shim required for the carriage on the same rail with a filler gauge & shim accordingly.
3)Find the best screw position by sliding the slave with the fixed carriage to find the smoothest position.
4) with the 1 rail in place, measure & shim the 2 carriage on the second rail, shim accordingly
5)then tighten by the master-slave method you described.

Poor maintenance seems to be common the world over
Interesting observation of the rails & slides in real life operation.
Pardon my English, are you suggesting keeping the rail dry is more pragmatic? Better off not lubricating the rails routinely?

[KenC]

Revisited my Control Panel & PC.

Bought a RM90 new PC casing to house the Atom board & its a breeze to work with.
PC.jpg


Reposition the PSU Capacitor & Rectifier
Control Panel 6.jpg


Reposition & redo mounting hole for BOB, Add a chassis mount DB25 plug using ribbon cable.
Control Panel 3.jpg


Reposition the contactor & changed the hook up wire to 18AWG for better mechanical strength. The yellow cable represent the external E-stop switch chain.
Control Panel 1.jpg


Added a cooling fan
Control Panel 4.jpg


Eventually, I use the 5 pins chassis mounted plug to get on with the work. I have a question here, can I solder the shield cable to one of the pin & connect the link the external wire shield? Is this how its done?
Control Panel 7.jpg


A close up of how the shield is connected to the ground via a thick 16AWG speaker cable.
Control Panel 8.jpg


Almost ready for final installation.
Control Panel 5.jpg

Double sided tape is my new found friend, I use them to mount the transformers, the capacitor, the DIN rail & the fan...

[bradm]

Yes, you can connect the shield of the wire inside the box to a pin, and connect that pin to the shield of the wire outside the box. You can also connect those to the body of the connector itself, assuming that your box is also grounded to the same place.

Personally, I'd be a little concerned about the long term life of double faced tape for holding heavy, vibration and heat generating items like transformers. A support screw or two would be easy insurance.

[Gerald D]

Originally Posted by KenC

You can use HeliCoil insert for the repair, once the HeliCoil is in place, it can take the wear & tear much better.

Standard Daimler-Benz practice on truck engines is to use "heli-coil" from the very beginning. This is apparently quite common with other companies and applications.

[KenC]

Originally Posted by bradm

Yes, you can connect the shield of the wire inside the box to a pin, and connect that pin to the shield of the wire outside the box. You can also connect those to the body of the connector itself, assuming that your box is also grounded to the same place.

Thanks for the heads up. will try soldering to pin but if I fail to do so (as the pin is small & the shield cable is huge....), I'll connect to the connector body.

Originally Posted by bradm

Personally, I'd be a little concerned about the long term life of double faced tape for holding heavy, vibration and heat generating items like transformers. A support screw or two would be easy insurance.

I'm in some way addicted to these beautiful tapes

They work nicely on car number plates. Some of which had lasted over 10 year as I was told by the seller.

I intended to find out it it can do the heat & load... You may realise I mount the big tranny so that the fall won't be too far.

Gerald, now you made me second though to inserting the HeliCoils.... MUST RESIST... OOOOHHHMMMMM.....

[javeria]

Helicoils are available - but a minimum qty purchase and the need of another set of tap's and then the tool to insert the helicoil -

if its not so critical best would be to drill a hole and have a nut on the other side.

Also ken, I would add fuses on the +ve line from the cap to the stepper drives, I don't though remember seeing it on the schematics.

[KenC]

I did considered the installing slow-blow fuse, but I learn that my drivers are fused & I have a breaker fuse in my breaker box.

Here, the Helicoils comes as kit c/w with a drill & tap. no min. quantity. You want some?

[cab. guy]

Ken,
I did not notice the rail key-ways in post#240.Your rail numbers are excellent.I like to have the blocks also key -wayed,for the purpose of screw securing,or help keeping them tight.I too had marginal error,between the vertical gantry and bed.A small shim
between the plate and spindle took care of that.Regarding the grease,I'm going to go with one pump of lithium, per bearing ,per 6 months,this should keep a very thin layer of grease on the rail.Great job you'll like it.

[KenC]

Ron, thanks for the grease info.

[KenC]

Good news & bad news,

My Huanyang VFD is back in business...A dear friend managed to repair it. He only need to replace a RM1 press button switch.

What a relief!

BUT my water pump refuse to work....

So my spindle + VFD set up test continue to stay in the pending tray....

[bradm]

Does the pump work when not connected to the spindle?

[KenC]

No, completely dead....

[javeria]

ken you can bench test the spindle without the water pump connected

[KenC]

I'm not that brave.... Tap water pressure is very low in my shop... Knowing the seller won't honour their warrenty... gotta double cautious

[bradm]

Heh. Very low tap water pressure is often much higher than what you'll get from a working pump. Plumb it up and see if you get any flow out of the other side. Almost anything beyond a trickle will be fine for testing.

[KenC]

No worries, my cable chain & springs just shown up, enough to keep me busy for a while. Plan to pick up another pump this week for the spindle, if I can find any, I'll have the tap water as plan B.
Thanks for the advise.

[KenC]

More parts came in for the last leg toward wood dust production

Cable Chain installed.jpg

Cable chain installed, use some 3" cable tray & cover to make the rack for mounting the cable chain. Flat bar for the mounting brackets.

Gantry assembly.jpg

A closer look at the Y-car cable layout

Y-car assembly.jpg

at 0 position.jpg

This how the Y-car looks, I have a strong feeling that I should install the Z-slide more towards the right hand side which is nearer to the 0,0 position... Should I move it?

Spoilboard dry fit.jpg

You won't be able to see from this pix but all 4mm pilot holes for the mounting bolts were drilled. Then I found out I don't have a wood drill bit (min. dia 18mm) that is big enough for the M8 pan-head bolt... Is there any negative effects using countersunk head for this?

[Alan_c]

Ken, nice progress and neat work.

That table is looooong!!!, I would have the spindle closer to the 0,0 end.

The bottoms of the holes for the pan head bolts should be flat, not angled - a Forstner bit is the best for that application, but if you have drilled the pilot holes already, try using a simple spade bit (cheap and nasty) to drill the counterbores before drill the 8mm holes all the way through.

[KenC]

Alan thanks for the heads up, so I'll have to wait till I get that 18mm or 20mm spade bits...

Took longer then necessary to get everything looking neat & organize, getting neat obviously not my strength.

The table is long capable of 12.5' x-axis.

I did it to use up all my 10m length rack, again an obvious wrong reason...

The work area is divided into 3 sections, the first is for the usual, 4'x8' sheet material , the other far end bay which is about 16" space between the cross channel, is for the future A-axis & the section in between is for what ever that fancy my ego...

Also there is provision on the A-axis side for side mounting sheet work for side notches.

[Gerald D]

I agree with Alan; move the spindle nearer to the Y-motor - it gives a better "connection" with the y-motor forces and it allows you to work further off the 0,0 end of the table (if you have tall pieces fixed there for eg. dovetail joints).

A countersunk head can split the material with its wedge force.

[KenC]

OK, I'm in the middle of repositioning, looking for a nice spot that nothing could run into each other. will post some pix soon.

[KenC]

How about this,
Repositioned Z-slide.jpg
move ~80m m toward the 0,0 position. Enough room to move another 40mm but the spindle will be dead close to the Gantry tube. In this position. Enough room to fiddle with the spindle when needed.

Also took the opportunity to re-fit the linear carriage & rails, being more familiar with the fitting now, the slide movement is even lighter