[Rodm1954]

Hi,
This is a joint project with a mate and we have been working independantly in our sheds on various componets but now it is all in one place and coming together.

Trolley is welded steel and base of machine is heavy angle and steel plates bolted together. Table top is 8mm aluminium sheet held down with push pull caps and grub screws which allows for fine adjustment.

Console has touchscreen, keyboard and machine control switches and pots operating through a Pokeys.

Gantry is 160 by 80 heavy Item beam and it weights heaps. All the rails are 20mm supported and have three bearings under each component.

Z axis is a THK KR33 double block actuator and is protected and strenghtened by plates.

Spindle is a 1.5kw air cooled and VFD operates through the console.

Electronics is Smoothstepper and Gecko G540 using all four motor outlets as it will have twin screws on X axis to eliminate racking of the gantry. All the ally plates have been CNC cut on a previously built machine. A lot of those plates are 16mm thick.

[DonFrambach]

Very nice!

[bobsch]

Very nice. Looks like a commercial machine, not DIY.

[palenn]

What do the "push pull caps" consist of? I like the idea of being able to level the table.
Nice machine!

[CNCfun&games]

Hi Rod,

It would be a real treat to see what you would come up with if you
designed your own alumunum & gray iron castings. Your Router would double as an excellent Pattern Making machine!

After a 6 month hiatus I'm finally putting the finishing touches on a router similar in size to yours. Our first project will be a pattern for a CNC lathe bed,
figures to be 1080 Pounds of Gray iron.

What's next for you??

Best Regards, W. Smith, Mission Viejo, CA

[Rodm1954]

Thanks all for your comments. It is great having somebody else in the shed to work with and chat as we go.

Palenn,
I have used the push pull table levelling on a number of machine builds and it is perfect for getting the top level. A grid typically 200mm or less square is set out on the table and at each intersection a grub screw is tapped into the table top. Next to that a cap screw is counterbored into the table top and threaded into the frame below. A dial gauge is set up on the Z axis and moved to each intersection and the grub screw levels the plate and then the cap screw is firmed up to hold it in place. Simple and effective way of getting the top level.

Hi CNCfun&games,
I have looked in your posts a couple of times and it looked like it had stalled or some other reason. I envy your cast iron construction and wish that something like that was available locally. You can't beat mass and the strength of cast iron in a machine. I also like the sentiment of it being an old technique - sort of combining the old and new technologies.
I have been toying with renewables and will probably do more of that once the machine is finished. The machine is about a month away from being finished as the bells and whistles add to the build time.

[Rodm1954]

The machine was moved last week using a car trailer and was thankful it had a winch to hall it up the ramps. It is a heavy machine with a lot of the steel being 3/8 thick.

This week all the wiring and configuration was done and last night the machine was commissioned - at last. It has taken seven months to build and my day job got in the way of an earlier completion.

Travel worked out to slightly over a half sheet and with a 3 phase spindle and 160 in/min cutting speed it was a good result for 387oz/in motors. Electronics is Gecko540, smoothstepper and spindle control through a DC06.
It has dual screws on X axis to keep the gantry rigid.
An air pump is installed with a flexible nozzle for the cutter. Rather than vacuum the sawdust/swarf the pump pushes it away from the cutter without making it airborne. The dust is then swept into the gutters down each side and eventually bagged through one end.

A console with a touchscreen is fitted and a logitech trackball added to be able to use a more conventional interface. An Xbox360 wireless hand controller has been added so that when away from the console the machine can be set up for the Z touchplate and laser crosshair positioning.

Everything is contained in the base and a filter in the bottom middle of the machine draws air with lots of 12 volts fans in the cabinet to create the air flow.

That's about it and apologies for some of the photos as it was difficult to get back far enough in the room to take good shots.

[RomanLini]

Beautiful work (again!) Rod.

I like the dust gutters idea too, makes sense on a smaller machine for easy collection of the chips. Especially with plastics and sign cutting etc that have the larger heavier chips that brush real easy.

[Rodm1954]

Thanks RomanLini

I have tried many dust solutions and I call this the passive system.

A shop vac just doesn't have the pull and a full ducted sytem does the job but is bulky, get's in the way for tool changes and if it is the vertical bagged variety it actually creates the dangerous fine airborne dust through the bags. I dare say you would probably be better off not using that type at all unless you house it outside.

I use an electro mechanical piston type aquarium pump which provides less than 20 PSI which is just enough to keep the dust and swarf out of the cutting path. The other advantage is they are quiet so you can use the machine into the night without a knock on the door from the neighbours. Very effective for all materials but it does blow out coolant when cutting ally so you have to spray more often when doing that.

You missed a good gathering and spread at Cairns but your PID was appreciated in the raffle - thanks for your support.

[Phife]

A shop vac just doesn't have the pull and a full ducted sytem does the job but is bulky, get's in the way for tool changes and if it is the vertical bagged variety it actually creates the dangerous fine airborne dust through the bags. I dare say you would probably be better off not using that type at all unless you house it outside.

Thats just not the case with a good dust collector, Ive been using dust collectors for years now.. Ive had up to 4 large dust collectors in my last woodworking shop. Most had 1 micron bags, and i never had an issue with fine dust.

The vertical delta dust collector i use for my CNC machine has a 0.5 Micron bag, I can tell you nothing is getting out of that bag. The bag is thick and the outside surface is dust free.

I cant see how using a dust collector can be dangerous or worse than not using one at all! If you have fine dust from machining, its better off being collected and properly bagged than having it floating around your machine and shop. Dust is bad for computers and electronics.

[DonFrambach]

Thats just not the case with a good dust collector, Ive been using dust collectors for years now.. Ive had up to 4 large dust collectors in my last woodworking shop. Most had 1 micron bags, and i never had an issue with fine dust.

The vertical delta dust collector i use for my CNC machine has a 0.5 Micron bag, I can tell you nothing is getting out of that bag. The bag is thick and the outside surface is dust free.

I cant see how using a dust collector can be dangerous or worse than not using one at all! If you have fine dust from machining, its better off being collected and properly bagged than having it floating around your machine and shop. Dust is bad for computers and electronics.

It depends upon what you're cutting. Wood chips are one thing but I found my shop filled with noxious fumes when cutting plastic empregnated wood even though the exhaust was passed through a HEPA filter.

Here's my solution to my problem: http://www.cnczone.com/forums/969923-post160.html

Bottom line: people are doing different things with their machines so different solutions are appropriate.

[Rodm1954]

Your's is an opinion and you are certainly entitled to it.

My theory is collecting dust through a vacuum system is only as good as the filtration of that system. What escapes through the filtration becomes airborne and thus a hazard to us. It is the finer stuff that you can't see that get's deep into our lungs and if the product is carcinogenic who knows what problem you have created for later years. We are using composite materials that are not like pollen and other natural airborne particles.

The process of vacuuming makes this stuff airborne under accelerated pressure on the output side of a vacuum system and in a closed shop it may be creating a problem rather than fixing one. Sure the big stuff is captured in the bag but that isn't the problem here. I have a ducted dust collection in my woodworking shop and I still get a fine layer of dust on horizontal surfaces if housekeeping is not maintained.

The concentration of these fine particles in a closed environment is what I see as a problem. The least disturbance of these particles is my theory to an effective passive collection system.

I can't verify any of this so it is my opinion and all I am I trying to do is open discussion rather than be defensive to your comment.

Positioning the vacuum in a safe location outdoors or fitting fine filters to your dusty is of course a cure to this.

[Eddymeister]

Hey Rodm1954

Nice build mate... Just wanted your opinion... I'm building one myself of similar size... (but probably not as many bells and whistles - I like the arm for the PC)... I'm hoping to achieve about 1200 x 1800 or 3/4 of a sheet... How are your Stepper motors going...?
I've taken an educated guess and order 640oz/inch Nema 34 for mine and will be using a dual screw setup on the x axis like yours...
Got any hints or tips mate...?

[Rodm1954]

Hi Eddymeister,
The machine is running 387oz/in nema23 with gecko 540's and can get close to 6m/min but have detuned that to 4m/min to make sure of no lost steps.
Acceleration is high and I see this as an advantage over top speed as the jobs this will do are usually in a 400mm square envelope - nested in the larger sheet but relatively short moves so acceleration is important.
I'm sure your 640oz/in motors will do the job.

Mass in the base is the key to a good machine. The intertia produced by rapid starts and stops needs to be absorbed by the machine or it starts rocking while cutting - harmonics. I use heavy steel in the base and table of the machine and all moving elements in ally. The gantry beam is 160 by 80 Item extrusion and the gantry sides are 20mm ally plate so quite substantial.

Another design feature is getting the X axis rails as high as possible to reduce the height of the gantry sides. The longer the distance between the linear rails and the next axis the bigger the lever you have created.

Hope that is of some help.

[RomanLini]

Thanks Rod, do you have any more info on the aquarium pump you use for air blower?

I think that would be ideal for my small plastics machine as it does not have air compressor access, but I never thought of aquarium pumps as the ones I have seen are tiny with little rubber booty pumps and would be lucky to make 2 PSI, never mind 20!

Do you have a photo or link to the pump?

[Rodm1954]

Hi RomanLini,

This is the model I have used on quite a few machines. It is an electro mechanical piston type.

Here

Looks like I have over stated the pressure as the spec says greater than 0.04mpa which converts to 6psi. How much greater is anybodies guess but I wouldn't think three times that would be right.

In any case ample air flow to push ally or acrylic swarf from a cut with a felxible nozzle at the cutter end. These are quiet to run once the hose is connected and I suppose this is why they are used on aquariums. No need for a tank and they are rated continuous run. I use clear beverage hose from the Big Green Wharehouse and a nozzle similar to this but with a round nozzle at the business end.

Greolt put me onto these years ago and it has become standard with each new machine. You can run them through an SSR and assign the output to M7.

[Rodm1954]

If you can stand watching the video this is a good example of how well they work. The noise of the spindle cuts out the pump noise.

This was my last machine and that nozzle was swapped out for a round one which concentrates the air to the cutter.

The pump is in the galvo box in the base of the machine - because it says electromechanical I get paranoid about EMI and house them in a steel box just in case.

[ame=http://www.youtube.com/watch?v=s98b07cyQKo&feature=related]‪Tubot CNC Machine.wmv‬‏ - YouTube[/ame]

[RomanLini]

Wow they are nice pumps, a little larger than I expected. I had only seen those tiny plastic aquarium air pumps.

6PSI (the ebay ad says >6PSI so it might be more?) seems plenty if it's supplying 125 litres/min, that's plenty enough air to blow the chips out of the way.

I'll look out for one as a coming project. It might even be possible to put a mister orifice in it for some lube mist to cut aluminium? I don't cut ally much as it's a pain spraying lube on by hand then having to stand over it brushing oily chips out of the way!

Thanks again!

[Rodm1954]

Hi Don,
I missed you post and must have been doing my slow typing when you posted.

Well thought through with exhausting the vacuum out the door and providing a cross flow of air in the workshop.

[MICA]

Hi Rod, very nice build.
Sorry to bring up an old thread, but I'm looking to build a similar machine.
Could you tell me what size ballscrews you used.
regards, Mic.