i am so glad to be part of the cnc world that i am anouncing a new machine build.

up to now i have been tinkering with a mdf rockcliff that i started about two years ago. the thing is a bit off-kilter and just a little slow. so ive been dreaming of all the new machines i could build. I ve got need for a few machines, a plasma table , lathe , mill. but my router is the main attraction at the mo. it was when i flipped through the photo gallery that i saw an alternative to my mdf wonder, an aluminium one.



I've been talking to the rockcliff people about the ability of the rockcliff and thought about milling aluminium with it. and now i think making the machine like S3rius385 did, only with ball screws + water-cooled VFD controlled spindle from linearmotion2008, that the machine could fly through ally like butter.

don't know what you think, but i am sure you'll tell me

something about a fixed-gantry just makes sense to me. i know you don't get the full axis of your rail but you do get ridgidity and an easily enclosed router. i'd also suggest the unsupported rails to a first-timer with a limited budget the 4m of rod i needed cost $30 and $8 a bearing.

any way I'M EXCITED.

Hi draughted,

I like the idea of the aluminium rockcliff. I have been working on a all steel version. I scaled the work area up quite a bit. Also to give you a idea of how much the frame is made of 4X4 steel tube. It's gonna be a monster. From what I've been seeing on the rigidity end of the build it performes like a Tormach PCNC 1100 but with a larger work area of course. Good luck with your build, I'll be watching your progress.

thanks

I've been thinking of steel, it would be cheaper but i like the ease of ally.a cold rolled steel would have superiour strenght.

so far I've designed the thing in Acad. and it seems to be OK, i guess the machinist will be the final judge.

does anyone know the how expensive a water cutter will be over laser. or weither plasma cutting is an option. ive choosen 12mm aluminium so i don't know if plasma will blow out the edge. any way if any one can advise as to the cheapest option.

http://www.cnczone.com/gallery/data/500/medium/lay-out_.jpg

this is the fruits of my labor
as you can see ive had it routed out, unfortunately the machine that did the job
was a 12meter monster with horrendous chatter and backlash, so my holes are square and my edges ruffled. but it is coming out ok.

will be finished in a few days.

http://www.cnczone.com/gallery/showphoto.php/photo/5689/limit/recentthis the complete router minus the limits

with this build going so smoothly
i think i'll make it public to the CNC community
it'll be a simple dxf plan. intended for a router or watercutter to cut the 12mm plate to shape
its a standard 12"X12"X5"
with the option to adapt the plans to suit any rail, bearing or screw.
but i assume the over all dimensions will remain the same.

i'd like your thoughts before going ahead because any old smo' can draw a plan but few can make one that satisfies the whole community.

85018
just to show you this is the plan i sent off to be machined
if you like it you can always have the dxf.

my machine is complete, nothing i can change now, however i can always give you a few pointers as to improving on my design.
like finding cheap bright-mild steel instead off the hardened shaft you might thinkof. making sure you buy bushings that have a thick outer diameter so the grub screws dont distort them when you tighten them for traction.

if you want to know the machining came to $380au
i then spent $50 on fasteners
$30 on 4m of rod
$108 on 12 bushings
$260 on ballscrews
and the electronics and computer and software i had from my rockcliff

from what i can tell igot back a machine that is faster, truer and more accurate than any MDF creation and could see me happy for many years

so if you find this interesting give us a reply and we'll se how it goes

Like yourself there Ted I made the RockCliff in MDF. Advice to all portntial Rockcliff builders, don't keep it in the garden shed where it gets damp. MDF is like blotting paper and distorts very badly with damp.

So I came up with a design that basically is the mdf version in Al angle.
I designed the replacement to use all the same metal components off the MDF version; lead screws, guide rails & bushings.

So after a few weeks in the machine shop at work, I now have a new aluminium angle version. I'm still using a router bought from B&Q with a modified base and it works the best. The only new components added were the lead screws. I changed the old M10 threaded bar for 10mm trapezoidal leadscrew and bought a tap to make my own nuts from phosphor bronze; Don't do it, spend the money and get them premade.

On my previous posting I had attempted to add 3 short videos of the new machine in action.

???

It tells me I lack a security token???

Lets try some screen grabs from sketchup

Anyone interested you can get the entire design if you care to take the time to unpack the model using Google Sketchup 7. I use sketchup to work out the concepts and redraw in ACad for machining. And still manage to get some holes in the wrong place!! Please don't ask me for dimensions, it's all in the RockCliff pack available from them. If you learn how to use Sketchup cleverly, it's all in the attached file ;-)

Maybe you can see that the bearing blocks are one piece across the rails. Be careful with this, the slightest burr or high spot throws everything off! and rails seize.

Enjoy

i like tihe look of a fixed gantry.

your angle iron construction looks up to it, do have any pics of the finished article. the only thing is that it would require some adjustment to get straight and square. the whole reason for going pre-machined was to cut out any defects in allignment.

at the moment i'm talking to gecko about the timing of there g540 which i obviously have set up wrong. it moves 120mm for a 100mm jog

recently i 've constructed an enclosure, some thing thats easy for a 12 *12 fixed gantry, its constructed of 20mm square tube and paneled with mdf but it is far from air-tight.

does anyone know the how expensive a water cutter will be over laser. or weither plasma cutting is an option. ive choosen 12mm aluminium so i don't know if plasma will blow out the edge. any way if any one can advise as to the cheapest option.

I have seen some DIY laser and plasma tables here on the zone. The best DIY laser's I've seen will only do very light cuts in paper and balsa. It's just too pricey to get a powerful laser. Plasma seems to be more reasonable price wise. But I wouldn't peruse either of them unless you only plan to cut through thin material. You end up with tapered holes with plasma if the metal is too thick.

From my research, water jet cutting is $$$expensive, loud, dangerous, and hugely messy when you are setting them up. 50k psi is nothing to play with. I'd love to have one but just isn't an option for the home in my humble opinion.

A few questions... I wanted to ask you about your bushings that you are useing, as I've seen them on several builds recently. Are they pressed into the holes? Also, how freely do they move? I'm really interested in useing them in a future build but I'm wondering how much power would be wasted in friction. I'm also curious of how long you can use them before they wear out. If you could give me some general information on them I'd really appriciate it.


Chris

i also looked at laser and water cutting
but believe that you should look for a milling machine to get it cut
the edges are blown out in most cases, plasma especially
but a milled edge is something you can count on.

in my case the waterjet was $700 and the milled cut came to $380

the bushings are a nice cheap option. they are held in place in my machine with 'grub' screws
which i have tapped in two places each ninety degrees apart for a firm grip. one point to note however is that i bought small thickness bushings and the grub screws distort off from round when tightened too much.

look at ebay for some nice ballbearing units, with mounts, at $8 each found at 2008linearbearing
do a special order.

the bushings are a nice cheap option. they are held in place in my machine with 'grub' screws
which i have tapped in two places each ninety degrees apart for a firm grip. one point to note however is that i bought small thickness bushings and the grub screws distort off from round when tightened too much.

look at ebay for some nice ballbearing units, with mounts, at $8 each found at 2008linearbearing
do a special order.

I noticed the grub screw holes and on other places in your build. Nice work. The way I envisioned useing the bushings would be with a locking coller. But that's after I got a machine that can mill aluminum. One day soon hopefully.