Newbie CNC Build

[JunkieHobbo]

@ motoxy: I have been and I am currently gather more information and then back to the drawing board. I know the Budget is tight, I do have an emergency fund if upgrades are required... ;)

@ kylelnsn: Would like to see the drawings once complete. Have you decided on the Electronics yet?

[JAZZCNC]

Hi,

First Kyle's got it all wrong I'm no master.. . . . But I have offerd advice with design thou struggling with finding time at the minute.!!

The machine(2 actually) I'm building which you referred to has high sides because the bed is adjustable. It will easily handle aluminium with bed set to it's higher settings keeping the Z axis extension short.
The adjustable bed as a few bennifits.!! It allows larger deeper material and/or the use of vices or 4th Axis plus allows flexabilty in material choice upto aluminium and even very light steel use with a decent spindle and correct cutters.
The high sides means the gantry sits direct onto the bearings giving maximum strength, no flexing flappy gantry sides.

These machines are a smaller version and losely based on my machine.They basicly incorparate improvements and lesson's learnt with my machine. They are an allround machine and very versatile which will do most jobs very very good. . . . BUT . . . If you want to just exclusively cut aluminium then I'd recommend you take a slight different route.

My machine almost exclusively cuts aluminium and without any trouble but if starting again to EXCLUSIVELY cut ALuminium then I'd drop the adjustable bed to gain Max frame strength, beef up the gantry and the Z axis and incorparate full flood cooling. . . . PLUS . . . I'd mount it verticle.!!! (See my post of mine roughly proped against wall cutting 10mm single pass)
While mine happily cuts at 1.5-2mm Depth of cut at 1000mm/min and will even rough upto 3mm(thou it moans a bit) just these few extra features will increase DOC and feeds plus increase finish quality.
My next machine will have all this plus an added unusual extra MAX Strength gantry/Z axis design which you'll just have to wait to see.!!

Regards good and bad PSU that depends.??
It's very important the PSU is sized correctly to the motors being used, unregulated supplys suit steppers better than regulated linear supply's and are the prefered choice because they handle the back EMF steppers produce when deaccelerating better.
Often it's cheaper and better to build a toroidal supply, doing this means you can size the voltage and amps pritty much exact to your motors ideal requirements.
It's a very common mistake for folks to buy the wrong size supply because they are confined to standard sizes available, often they buy too low voltage which is a big mistake. Steppers get there speed from voltage so it's extemely important to get this correct so in this regard yes there is good and bad.!!

I'll say to you what I say to everybody.!! Don't buy a thing untill you have fully settled on the design and know the materials and have an idea of weight's etc to be moved around. With £1000 budget you can't afford to buy a single thing wrong but it is just about do able.

Just ask if I can help and I'll try.

[Jonathan]

I have looked through the Forum and have seen a machine similar to JAZZCNC with lower sides, made by Jonathan. I have PM'd him to see if he can post more pics of it as it looks like it would do the Job.

I'm sorry I forgot to reply to your PM earlier about pictures of my machine and things. Had a bit more work than usual to do at Uni. Looks like Jazz has saved me the trouble of answering lots of questions :)
There's quite a few pictures in my build-log, especially towards the end:

http://www.mycncuk.com/forums/showth...outer-building

(starts off embarrassingly bad then gets better!)

There are a few things I will change on the machine. Essentially just a stronger Y and Z-axis with profile rails, but like Jazz I have an 'unusual extra strength' design for that. Instead of having one piece across the gantry there will be two, with one Y-rail on each, and a box shaped the Z-axis operating between. Having said that it's still strong enough to cut aluminium at a decent speed 1.5mm DOC, or more with reduced finish which is not bad considering only round rails. I just want to see how much better I can make it...

If you need any more of specific parts just let me know and I'll take them.

I'd be inclined to add some triangles to that frame to stop it skewing.