Easy Build 800 x 500 x 85

[Daniel233]

Ok it’s my turn now and all know the drill, long time reader first time poster blah blah blah.

My background is fitting and machining I have worked on various CNC machines including center lathes, turret mills, machining centers, wire cutter and of course a router and I currently work as a contract draftsman.

5 years ago I decided to convert my lathe/mill to CNC and did so on a very tight budget, this clouded my judgement and I made a poor motor selection. In order to break through the friction of the machines slides I had to run a reduction that saw the machine having a top speed of 200mm/minute. I found it extremely slow and frustrating and proceeded to shelve the idea.

So a few years passed by and I decided that I had a perfectly good driver setup and motors going to waist when really all I needed to do was use them on a machine with less friction and lighter cutting loads. I looked at a wire cutters and sink edm’s but didn’t think they would be useful in most of what I do or would like to do.

That's when the router idea came up, I found CNC Zone and started putting ideas together. I looked at simple designs for a first machine eg. jgro and made 3d models of my own concepts which led to more complicated designs that would require manufacture on a CNC. I have been going round and round in circles and have completed several models but achieved nothing.

So I decided to get serious, make some firm decisions and finally make it happen. I put together a model that was easy to build at home with hand tools and my lathe/mill. I bought some materials and prepared to start my build. However my timing couldn’t be worse as I am in the middle of renovating my house (another long drawn out project but I won’t bore you with that one) and I have very little spare time on the weekends. Deciding nothing can stop me now I decided to build it on week nights. So this project will be a slow one I feel it will take 10-12 weeks of 1-2 hours 5 nights a week.

The machine:
Controller – Laptop running XP and Mach 3
Driver – Hobby CNC 4 Axis board (Purchased 5 years ago so different to their current board which intend to upgrade to at a later date to increase my top speed)
Motors – 3 x Unipolar 127 once/inch NEMA 23
Router – Working area 800mm x 500mm x 85mm, Timber construction, Skate bearing slides, threaded rod lead screws.

The model is 99% complete I need to extend the table 50mm add a few fasteners and limit switches but everything else is complete. I have completed drawings for the z-axis and started machining some of the parts. I have attached pictures of the model (Later I will add an E-Drawing if anyone is interested) and photos of my driver setup. I endeavour to update my log weekly and include photos. I hope my log is interesting and helps others to embark on this truly enlightening hobby.

[Daniel233]

I have started making parts so far I have turned up the z axis lead screw the acetal lead nut and milled the z axis bearing mounts. I will be building the z axis assembly first to check that my design works well then I will build the rest of the parts in full batches.

[jeroen87]

Hey Daniel233,

welcome to the forum

nice looking machine, I'll be following your progress!

Have you considered using 2 leadscrews for your x-axis? You already have a 4-axis controller, and it could increase the stabiltity. I would keep this option open just in case.

good luck with your build from another "newbie" on the forum.

greets,

Jeroen

[Daniel233]

Hi jeroen87,

Thanks for your support. Yes I have considered running a double lead screw x-axis but as I plan to replace my driver board and upsize the motors I don't want to spend any time or money on them. I am going to build it and see if it will be acceptable without it at this stage but if it is needed I plan to slave the 2nd lead screw off the first with a toothed belt.

Cheers

[harryn]

Nice start on the project.

You are right about the driver and motor - a bit undersized, but sufficient for learning.

Do you have an idea / goal for the spindle motor and running speed desired ? I am thinking that your setup would be ideal for a circuit board router or perhaps routing pictures into wood - is your thinking something like this ?

[Daniel233]

Hi harryn

I am hoping to be able to push a 5mm or 6mm cutter through timber, plywood and mdf in order to make identical parts for a more serious 2nd machine. I intend to do so in multiple smaller cuts of a size the machine will be capable of.

Cheers

[Daniel233]

Tonight I added the holes and slots to finish off the z-axis lead nut. I assembled it on the lead screw with a circlip for pre-tension to prevent backlash and it works perfectly.

[Daniel233]

Today I purchased the timber for the z-axis and y-axis frames, I routed the chamfers on the z-axis and y-axis boards that support the angle rails. I cut must of the plates for the 2 axis’s and completed the z-axis side plates.

[Daniel233]

Today I made some more parts for the z-axis. It was a bit fiddly to get the right width on the front and rear plates so the slide would move freely, I think the other axis's will be better as the side plates are longer and will accommodate more flexing.

[Daniel233]

I finished the plates for the y-axis last night. My next move is to make the motor and lead screw support plates for the z-axis and then I will be able to hook the z-axis up to the computer and see how well it works.

[TOTALLYRC]

Ok it’s my turn now and all know the drill, long time reader first time poster blah blah blah.

My background is fitting and machining I have worked on various CNC machines including center lathes, turret mills, machining centers, wire cutter and of course a router and I currently work as a contract draftsman.

5 years ago I decided to convert my lathe/mill to CNC and did so on a very tight budget, this clouded my judgement and I made a poor motor selection. In order to break through the friction of the machines slides I had to run a reduction that saw the machine having a top speed of 200mm/minute. I found it extremely slow and frustrating and proceeded to shelve the idea.

So a few years passed by and I decided that I had a perfectly good driver setup and motors going to waist when really all I needed to do was use them on a machine with less friction and lighter cutting loads. I looked at a wire cutters and sink edm’s but didn’t think they would be useful in most of what I do or would like to do.

That's when the router idea came up, I found CNC Zone and started putting ideas together. I looked at simple designs for a first machine eg. jgro and made 3d models of my own concepts which led to more complicated designs that would require manufacture on a CNC. I have been going round and round in circles and have completed several models but achieved nothing.

So I decided to get serious, make some firm decisions and finally make it happen. I put together a model that was easy to build at home with hand tools and my lathe/mill. I bought some materials and prepared to start my build. However my timing couldn’t be worse as I am in the middle of renovating my house (another long drawn out project but I won’t bore you with that one) and I have very little spare time on the weekends. Deciding nothing can stop me now I decided to build it on week nights. So this project will be a slow one I feel it will take 10-12 weeks of 1-2 hours 5 nights a week.

The machine:
Controller – Laptop running XP and Mach 3
Driver – Hobby CNC 4 Axis board (Purchased 5 years ago so different to their current board which intend to upgrade to at a later date to increase my top speed)
Motors – 3 x Unipolar 127 once/inch NEMA 23
Router – Working area 800mm x 500mm x 85mm, Timber construction, Skate bearing slides, threaded rod lead screws.

The model is 99% complete I need to extend the table 50mm add a few fasteners and limit switches but everything else is complete. I have completed drawings for the z-axis and started machining some of the parts. I have attached pictures of the model (Later I will add an E-Drawing if anyone is interested) and photos of my driver setup. I endeavour to update my log weekly and include photos. I hope my log is interesting and helps others to embark on this truly enlightening hobby.

A couple of things come to mind in no particular order.
1.The motors and drives sound awfully small for this machine also.
2. Laptops and Mach3 thru the pport don't mix.
3.What you need is the special hammer that I recently made. It works well on both machines and the operators.
4. If you designed the mechanicals incorrectly, it must be a controls problem!!!
5. You will be supprised at how fast you have to go in wood so as not to burn up the bits.

Good luck.
Mike

[Daniel233]

Hi Mike,

Yeah I know the motors are on the smallish side I am just hoping they will be usable. I have assembled the complete z-axis and the motors are capable of driving it at 300mm per minute and I can’t stall the carriage by hand. Whilst I know this is a slow feed rate for timber I am hoping that by slowing the router speed down to around 10000rpm and taking a 0.5mm finishing cut I will still achieve reasonable results without burning the timber. I have also come across reports from people using PP ports on laptops having problems but I have Mach 3 up and running driving the motors without any problems, I must be one of the lucky ones.

Cheers