2AM: I wonder if the table saw will wake the kids...

[10bulls]

Welcome to my first router/mill/cnc project.

With 2 young kids and busy job, build progress is not going to be meteoric. By the time the dragonlets are abed, kitchen tidied, dog walked etc, I'm doing good if I can get into the garage by 10pm (sleep deprivation permitting). I see by other posts I'm not alone in this. What is this 30ish post baby bloke thing?..."Urrrh tired...urrrgh...must...make...CNC macheeen!"

I've recently acquired a 7x12 mini lathe that I'm trying to get to grips with but my turning ability is currently only marginally better than my welding (which looks like something a bronchial volcano might spit out).

I've decided to go for an aluminium build; mainly because I'm sick of the sight of MDF after using it in a number of household projects. I still disturb the occasional drift of MDF dust when exploring the darker depths of my garage. MDF also == painting (me no likey).

So without further ado, here is a rather amateurish CAD drawing of my design
(complete with magical floating motors!)

The slides rails are from old printers, the aluminium is from some rather chunky extrusions I blagged from a local business. The Y carriage is initially going to use a pair of bushings from the printers and the X is going to use a rather shonky design I came up with using blocks with 2 pairs of roller bearings that run on the rails on their chamfered rims. A prototype I made of this tells me it should work but my rails are going to end up badly grooved and zoner Splint also points out the excessive thrust load on the bearing. I'm going to build the Y axis and gantry first so I may change my mind when I get to the X.

(I do hope I've got my X and Y nomenclature the right way round...I'd hate to come across as a dumb newbie...even if I am

(the zip file contains a dxf)

Regards Andy

[10bulls]

Progress over the weekend was not great.

I spent what little time I had farting with the table saw trying to get accurate, square cuts in the aluminium profiles. I have come to the conclusion that this is not a precision machine. Fortunately my design doesn't call for anything too accurate, apart from the 2 cross pieces for the gantry. On top of this, wifey found lots of aluminium chips in the sack of potatoes in the garage

The 'L' profiles are actually cut offs from some hefty profile shaped a bit like |_|'''|_|
It was a bit of a buttock clenching experience feeding 4ft x 10in lengths of the half inch thick profile lengthwise down my aforementioned wobbly table saw. Yay Ear Defenders!!!

Another frustrating experience was trying to cut off blocks from a 1" by 0.5" steel bar using a cheap gadget that clamps an angle grinder to make a sort of poor man's chop saw. It works dandy on 2mm box section but took several minutes to hack, burn and wobble it's way through the solid bar.
I've since cut all the blocks using a hand hack saw which went surprisingly well in a hand crampingly sort of a way. Yay Hacksaws!!!

Attached is a picture of some of my raw ingredients.

The grey bits bottom left are the bushings for the Y slides. They are going to be a pain to mount as the bit with the mounting holes is not really flat and the only flat sides don't have enough metal to tap holes into. Learning to make accurate bushings, pillow blocks etc is definitely a priority after phase 1.

Also shown is a stepper I'm going to use initially and a servo I'd like to use eventually. The stepper is connected to PIC16F84 + L298N boards I designed a few years back. (look at the purdy spinning motor go round and round and round and...)

I like the look of the PICStep boards that Alan (Garfield2) has created and I'm hoping that if I keep telling him what an extremely clever, generous and ruggedly handsome individual he is, he may let me try his PIC Servo design

[ViperTX]

Hey good work. Generally the gantry has the Xaxis and the Zaxis and the table is the Yaxis.

Got the wife, the kids, the pet....yep, been there....now gotta have some creative fun.....tools......mechanical marvels connected to electronic gizmos.....yeehaaaaa!

[ger21]

Originally Posted by ViperTX Hey good work. Generally the gantry has the Xaxis and the Zaxis and the table is the Yaxis.

I think it's the other way around. Usually the gantry is Y and the table is X. It will work either way just fine. I've heard that the proper method is to designate the longer of the 2 axis X, and the shorter one Y.

[Ferenczyg]

If I am not in a mistake, the explanation was in one of ballendo's post and talks about designating X not the longer axis but the one that can bear the largest raw material

/F

[10bulls]

I hadn't realised this confusion on my part would open up such a can of worms.

At peril of ruining my parts by machining them 90 degrees off I have hereby decided
to introduce a much less ambiguous naming convention.

The long axis will hence forth be called John (as in 'long'...get it?).

I decided against calling the Y axis Jesus (goes across) on the grounds it might offend and lose me some friends, so I decided upon Paul.

This results in what was my Z axis is now known as Ringo and my CNC rotary table
(should ever I be blessed to live to see it built) will be called George.

Regrettably this does limit me to building a 4 axis machine as
A) I can't remember the name of the original drummer who left and...
B) I couldn't tell you what a 5th axis might be even if one came and danced on my lap.

[santiniuk]

Hey Andy,

Good to see you have started your thread and have added some light hearted humour to the forum. Quite entertaining !

I imagine the debate over the axis names is not over

I had an issue trying to get square cuts on the aluminium profile too. Thankfully I bribed a friend and he milled the ends square, (Just as well - they were not pretty)

I can sympathise with you about time and kids. Never enough to time to get the Geeky stuff done....

I look forward to following your entertaining thread....

[ViperTX]

Well the Cartesian coordinate system doesn't care...just put big labels on your axis so when you take pics and talk about stuff everyone....well most everyone will remember the coordinate system you're using.....The only time you'll run into problems is when you go from someone elses CNC mill, to router, etc.

80/20 always does a good job on cutting their extrusions....I wonder what their local dealers use for a table saw...the blade is a triple grind carbide tipped blade.

[MrBean]

Hi. I'm enjoying your thread. Good start. It's nice to see another UK CNC builder entering the arena. What length and diameter are those printer rods, your bearings are running on?

I've got a machine built, but it needs some fine tuning, alignment wise. Will hopefully get more done at the weekend. (kid, dog, cats, work, etc, etc....) You can see it here:.....if you're interested.

http://www.terry-is.f2s.com/

Keep the updates and pictures coming. Looking forward to watching your progress.

Regards Terry.....

[trubleshtr]

I always use the right hand rule when describing co-ordinate systems, for fun I typed it into google and the first link below actual gives some good visuals for co-ordinate systems as well as g-code explanations.
The second link I stumbled accross is just cool, 5 axis cnc machine (home made)


http://www.media.mit.edu/physics/ped...-tutorial.html

http://www.rainnea.com/cnc.htm

[trubleshtr]

Ooops...I made a mistake, althought the first link does provide good information, this was the link I ment to show.

http://www.utm.edu/departments/engin...cture%2025.pdf

[DAB_Design]

*edit* sorry noticed topic was straying a bit.

10bulls welcome. You've got one necessity that is mandatory to be a machinist.....a good sence of humor.