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Fozz84
13-03-2014, 11:27 PM
Hi all, My name is Rob.

Since completing my degree a couple of years ago I have been moving from dead end job to dead end job... ...the thing is I was rather good at 3D design and construction. So I am trying to build a CNC Router with a cutting area of 1200mm x 1200mm to cut up to 18mm ply. (I don't fancy cutting out 300 components for my furniture out by hand.) I would like to experiment with thicker materials such as engraving designs into 2" soft hardwoods In the future.

As a realist I was wondering if any of you have Machines that use aluminum extrusion (cost in getting some one to weld out of steel and deliver is not an option ) as the frame that I could basically copy!

the cutting tool i wish to use is this; RT0700CX2 1/4" Router-Trimmer Makita (http://www.fastfix.co.uk/makita/Makita-RT0700CX2-Router-Trimmer.html) (I just LOVE Makita tools, and this bad boy is so useful it deserves it's own thread :) )

My other requirement (another reason for the aluminum) is due to my crap job I will have to start out with cheep parts/Motors/Ball screws/belts and upgrade when I can afford it!

If anyone can suggest a suitable package deal on the motors and controller for my entry level CNC you deserve a Digital Hi Five.

:joyous:

Washout
14-03-2014, 11:37 AM
Hi Rob,

My build log is for a machine I built from aluminium extrusion http://www.mycncuk.com/forums/gantry-router-build-logs/5139-its-begun.html

As a word of advise I would say using extrusion is going to be more expensive than box section steel and you are really saving yourself the time learning to weld (and the cost of the kit if you need to buy welding gear) or the cost of getting someone to weld the frame for you. Extrusion I would not say is quicker either, as you'll find out after tapping a couple of hundred holes for bolts ;-) Its simply more convenient and easier to get going on a build for a "non welder".

That said my extrusion based machine is operating pretty well these days and one good advantage of building the frame from extrusion is that adding stuff to it is generally easier as there's lots of slots to bolt stuff to (sensors, stops, additional bracing, 4th Axis etc).

There are others, but I went with a 3 axis 3nm stepper motor kit from Zapp Automation, which iirc came with motors, drivers and PSU. I would also highly recommend the 2.2Kw water cooled spindle and matching VFD you'll see mention of in many threads over say a normal air cooled router spindle - they are per Kw cheaper than the router you linked, very quiet and take a range of tools with a suitable set of collets.

Last bit of advise is to get a Sketchup design on here and await feedback from the likes of JAZZCNC and Jonathan etc. who helped me massively in getting a less than half decent design to an almost fully decent design :-)

Best of luck with your build and hopefully we can see a new build log soon.

JAZZCNC
14-03-2014, 02:59 PM
If your good with design then why copy.? You'll be bettter designing something that suits your exact needs and is within your skill/equipment range. For instance I've built several machines that size which use profile or steel but no point giving you the designs for them because you can't machine parts and you can't weld.
So to me you either have to design machine so it can be built within your means or Employ someone to help who has the equipment and skills.

Washout is correct regards cost of steel Vs Profile, it's much cheaper. It's the hidden cost's of profile that catch people out, things like T-nuts,Corner brackets Etc and if you try to skimp and not use these then profile is a bitch to work with. It doesn't drill nice, it doesn't Tap nice and you can bet your last £ you'll want to put a hole where there's no material.

Steel on the other hand is much cheaper Per meter if bought from a decent steel stockist, typicly £30-40 per 7.5mtr length of 50x50x3 compared to £25 per/meter(£187.50 per 7.5mtr.!!) of 45x90 profile.
Steel is easy to work with just a few tools, Grinder,Hacksaw, drill and cheap Arc welder. Holes are easy drilled and tapped plus if/when you cock up it's an easy fix to fill hole with weld, grind back and try again.

Look around forum and then design to suit your needs post it up here and we'll point you to any changes that need making.

Word of caution regards electronics is don't buy Cheap drives or Kit packages you see on Ebay etc. It's false economy and leads to head banging problems. Also don't buy them untill needed for warranty reasons and this will probably be several months after frame is started.!

Fozz84
14-03-2014, 03:38 PM
this reply has to be quick I am at work!!! is this the kit you went for Washout! Digital Driver Kit Two (Three axis) (http://www.zappautomation.co.uk/en/stepper-driver-kits/768-digital-driver-kit-two-three-axis.html)

Washout
14-03-2014, 04:14 PM
Ah I don't think Zapp do the kit I bought anymore and the closest to mine is the High Voltage 3 Axis one here: High Voltage Digital Driver Kit (Four axis) (http://www.zappautomation.co.uk/en/stepper-driver-kits/772-high-voltage-digital-driver-kit-four-axis.html)

The description has an error as this is actually the 3 Axis kit using DM856 drivers (mine was an earlier analogue version using AM752 drivers).

If you are going to cut wood only (I cut a lot of aluminium) then you maybe able to use the lower voltage kit - others will be able to advise.

As Jazz says though - the electronics is something further down the track - get the frame, gantry, ballscrews, rails, bearings etc. sorted out first.

Jonathan
14-03-2014, 06:11 PM
If you are going to cut wood only (I cut a lot of aluminium) then you maybe able to use the lower voltage kit - others will be able to advise.

Higher voltage lets you go faster, so if anything it's the other way round since in general the feedrates for wood are higher than the feedrates for aluminium.


As Jazz says though - the electronics is something further down the track - get the frame, gantry, ballscrews, rails, bearings etc. sorted out first.

Agreed.