How to use Ubuntu - Klang Malaysia

[Gerald D]

Of course you can use bolt & nut. But then the tuning (shimming) becomes a pain because you need both hands to tighten each screw. Those screws are going to be tightened/loosened lots of times.

[KenC]

I went on drilling new hole on the beam using the rail as template, finished drill & tap on on beam, almost done drilling on the 2nd beam now... should get this over before midnight...

[KenC]

Viola, got the rail & beam holes drilled & tapped.
On dry fit, they look straight to my eye for now.
Dry fit Rail on beam.jpgDry fit Rail on beam 2.jpg

I think I can safely stow most of my power tools away from here on...

Its been exhausting 1.5 months since steel fabrication started & I'm very happy with the result, exhausted but very happy...

Need to take a break to fulfill my family responsibilities in preparation for the forthcoming Chinese New Year which happens to fall on Sunday the Valentine's day this year (or Spring Festivals shared by the Jap, Koreans & other orientals.) will have a week long festive break before I resume work & fun...

[Claudiu]

Looking good`n`straight, Ken. Happy weekend!

[KenC]

Claus, thanks for the kind words.

Its been 4 days since I left my baby MM for our Chinese New Year celebration & I'm suffering from severe MM withdrawal syndrome....

[Jan de Ruyter]

Ken, I sent you a mail, did you get it?

[KenC]

Jan, Sorry, no mail in my box.

[KenC]

Found some time to play today.
I read somewhere in the forum that 0.01" is the number to aim for but 0.254 is a quarter of a mm so naturally I attempt tighter tolerance just for the sake of it.
Using a 10' long straight-ish Alum rectangular profile as straight edge. and plenty soft drink cans for shim
In no time got the height within .25mm, then I proceed to 0.2mm took a little more time & 0.15mm is do-able, 0.1mm it starts to get difficult, can only get ~80% of the rail to get within this range & 0.05mm looks almost impossible.
I wish to know what is the "enuf" rail height tolerance?

[riesvantwisk]

Ken,

enuf depends on what you are planning to do with your machine.
If you are just cutting, then hight is much less of importance then when you do 3D carving.

If you do 3D carving, then it depends on if you are making big items or small items.
For woodworking for me it sounds like anything below <0.2mm is enuf, somebody else might need something more accurate. But don't forget there is sandpaper


Ries

[KenC]

Ries,
Thanks for the heads up.
I should also list down my requirements, will definitely do carving eventually, will use mostly on sheet plywood, mdf, plastics, soft metal such as Alum & brass, but most probably for ornamental work & normal precision work, don't expect to machining space shuttle components

Wonder what the others did.

[riesvantwisk]

Ken,

IMHO the following is important:
1) Constant height over small distances rails shouldn't jump and look bumpy.
2) Sturdy en reliable gantry, Y car and Z-plate, if you push/pull anything the only you should see moving is the spring a tiny bit, nothing should feel loose.
3) Good router/spindle (own experience).

You see, if you make a ornamental, then nobody will see that the left side is 0.2mm higher or lower then the right side, given that left and right is reasonable distance apart and given the nature of a ornamental this is something that the human eye will not see.

You would only see un-even machine results if something has bumps, height differences on the rail over small distances.
And even then, the gantry is so large then even a 0.2mm bump on once side will result in the middle of the work table roughly 0.1mm difference.

What I did notice is that low speed performance of the motors are important and that you need to set good CV settings in EMC or Mach3. In EMC it's G64 P0.1 that gives me a smooth ride for cutting my MDF.
If you don't set your CV settings proper for the job, then you can get chatter, in the beginning my machine started to resonate a lot because of wrong CV setting. You will notice it, it will behave shoky.

Ries

[KenC]

From what I have now, I can foresee that the gantry & rail gerald design will be more the stiff enoug, surely I don't have to worry about that. Thanks again gerald.
IMHO, judging from the way MM rails are align, it is surprisingly undemanding! Only one rail is align on x & y plane, then the parallel rail is set only by the guide rod... which from my experience could give nice +/-0.3mm accuracy (parallelism of the rails) at best... & there is inaccuracy in the edge grinding process which I presume to be +/-0.2mm at best... It is really mind boggling
Your post on your CV setting caught my keen attention, will pay extra effort on the when my MM make dust.

[KenC]

Found enough time & patient to alignment just one x-rail today.

Introduce the fishing line guide & getting closer alignment is possible. Managed to bring all the height within 0.1mm which translate into +/-50 micron. Couldn't get any close as my coke can shim is 0.1mm thk implementing fishing line method.

I us 0.5mm fishing line so the rail straigtness won't be better the +/-0.25mm. I guesstimate at about +/-0.3mm

I know its closer then necessary, BUT ... just couldn't resist getting them closer while I'm at it...

##PS, Did took some pix but doesn't show much at that size level....

[KenC]

孔子日: 有朋自远方来, 不亦乐乎

(Confucius said : with visiting friend from a great distance, the joy is unmeasurable.)

Jan de ruyter in my shop.jpg

Picked Jan De Ruyter from his hotel about 2:30pm, brought him around Pasar Rd where I found most of my electrical & electronics stuff. Gave him a whirl wind tour around my neighboring ultra light industry village in Klang, then proceed to my lair. When the heat got too much of us, we went off to a cafe for a long chat then finished off with a long chat over diner in a local eating den.

Its been a pleasure having him.

[Jan de Ruyter]

Thanks Ken, I really enjoyed the visit and the company. Being on the hop all the time is certainly tiring and spending time in KL this time was indeed a pleasure. Visiting the normal tourist attraction never gives you a good indication of how people life in a county, so the tour of the industrial area was very interesting. Amazing what people can do with so little. The bak kut teh was delicious!

One thing the visit proved to me that I should get a certain part of my anatomy in gear and just do it.

I really appreciate the effort you went to and would like to extend an invitation to you (and all the other MechMaters) to visit South Africa.

[Gerald D]

Ken, you should have taken Jan for a steamboat!

[Kobus_Joubert]

Hell Jan, going to Malaysia to see a MM is a bit extreme....Brakpan is not THAT far from PETORIA....oooo sorry, I talk like my son that study in Pretoria...

[KenC]

Originally Posted by Gerald D

Ken, you should have taken Jan for a steamboat!

I would if the weather is not as hot. Jan was sweat through by just sitting there... He'll sure lose a few kg if he go through the steamboat threatment

Jan, I enjoy having you around very much, & am glad you enjoyed the Bah Kut Teh. Working on the MM in near physical solidarity is tough mentally, don't think I would had came this far without this forum & your visit sure fuel some new drives.
I would love to visit SA in the near future, but I would like to do that when you start work on your MM, remember what we discussed? Holding the MM parts you already purchase is equivalent to holding inventory. Build it & you may generate some revenue...
Before I forget, thanks for the Elephant Liquer, BTW, what is the best way to enjoy the Elephant liqueur?
Cheers

[Gerald D]

Amarula

(the date of birth question is because of legislation preventing promotion of alchohol to under-18's)

[Jan de Ruyter]

Kobus, it was a choice, a Brakpan burger or Klang Bah Kut Teh. BTW
1) Is there any truth in the rumour they are going to make Boksburg, Nigel and Brakpan one town? What will the name be? That will determine if I will venture going there.
2) I have a job for you, I need a dibbler for seedling trays. Can you help?

Gerald: tonight I'll go steamboating! So many choices around here!

Ken: The way to enjoy Amarula? Without the elephant. Either neat as an after dinner liqueur or with ice.

[KenC]

Good thing it doesn't require a plate of stir fried elephant meat to go along.
I left the Amarula in the fridge & will have a some tonight.

Found time to proceed with the 2nd x-rail. Managed to get them within 0.1mm height & straightness is about 0.4mm. Is this enough?

Another question pops up, The rail grind is not absolutely precision, certain part of the knife ridge are narrower & certain part are wider the variation is small about 0.5~1mm, I align only one corner, i.e. the corner made by the 45deg grounded edge to the horizontal ridge. by pulling a 30lb fish string with 0.55mm diameter. I used the gauge rod to set the two ends of the rails then lay the fishing line through this 2 point of the corners. once I'm finished straightening & adjusting the rail height, I checked the space between the x rails & I found the spacing is inconsistance, at places I get about 0.5mm gap & at certain place I can not push the gauge rod in... Will this be a problem, do I need to do more straightening?

[KenC]

Help needed for the Gantry roller on the x-rails.

Is it mandatory to have all the wheel surface in perfect contact with rail? I get wheels "lift" or is it no contact on one side in some position along the x-rails. Is that normal or I did too little?

[Gerald D]

Jan a fancy dibbler on his indexer? or a flat, hand one?

[Gerald D]

Ken, you now need to use your gantry as the gauge rod. In other words, move the rails a bit to improve the gantry's ride.

I think it is normal to get a bit of wheel lift before the motor springs are fitted. But, you must try and get firm contact on all wheels after fitting the motor springs.

[KenC]

Thanks Gerald. Will see how to go about this.

Firm contact means the V of wheel mesh completely with the rail? Meaning shim on the wheel is required? At this stage, I measured .2mm (worst case) gap between the rail & the wheel.

I guess the next thing to do is get the rack welded, tape on the angle, mount the motor & spring on to be sure.

[Gerald D]

You can just load some weight on each end of the gantry to see if it pushes into contact.

[Jan de Ruyter]

Gerald, like an elephant?

Ken, put the bottle on one side of the rail. Take a sip. Go back to the other end, check the bottle from that end, if you see one bottle, take a another sip, go back, do this until you see two bottles. The gantry will then be ok and you will be a lot happier.

[KenC]

LOL!!!

Let me go around the neighborhood to see what I can find as weight...

Thanks again

[KenC]

Found 2 empty 18 liter oil containers in someone's rubbish.

Filled with water & I have 36kg of weight. Now I can get on with it.

Weighted Gantry.jpg

BTW, even with lifted wheel, it rolls real smooth!

[Kobus_Joubert]

Jan, just say when and where and how big. Sure can make a plan.

BTW Ken it is looking good so far