4R8's table build

[4R8]

I used steel at 4mm thickness.
Originally the design called for 100mm square Al but after deciding to add the option of occasional light routing, I went the steel route.
I'll lose a bit of acceleration with the extra weight and hope to combat that by going with the 425oz steppers instead of the 300's.

Depending on how light you get your carriage, you may need to add some form of additional support to stop it flexing during direction changes. One method, and the lightest is to use a strap with an adjustment bolt in the middle. I'm not sure how to explain it well. They use the same method in sheet metal brake construction for fine adjustments to keep the unit flat and true.

Aluminium extrusions are generally quite accurate and more than good enough for plasma application. My father runs the local Aluminium supplier's warehouse so I get anything from the offcut rack for much less than scrap value, that is if I get charged anything at all

[sasquatch]

Great project, thanks for posting the follow along pics,

[4R8]

(11-16-2012, 08:42 AM)sasquatch Wrote: Great project, thanks for posting the follow along pics,

Thanks mate, hopefully by the end (or during) someone picks up a few hints on what works (or doesn't).
I'm almost caught up with what's happening in real time so the updates will slow substantially as I generally only get one day a week out in the shed with the occasional evening when i set the dogs free to roam the scrub behind our house.

On a home note, the little guy (6 weeks old) finally had a night of rest which allowed myself and my partner to get the same
Hopefully his days and nights are close to being sorted

[4R8]

The next installment...... The controller

I wanted the computer separate from the machine as I'm not sure on where the machine will end up in the shed once it's completed, or the orientation in which it will sit. So I went with the following, which will undergo a few changes shortly as plans have slightly changed.

Here's a quick one with a few details to follow.


I bought a rolling tool cabinet that, in my eyes suited the application perfectly. It originally had the base as shown with another section ontop which had two more full width drawers and six 1/3rd width drawers. I picked it up for around $120.
The idea was to house the PC in the lower cupboard but unfortunately the PC I have is a flat unit, not a tower style one and did not fit.
Instead I used the lower section to house the power supplies, Torch height control unit and stepper drivers. I used Al pieces sourced through my father and built a rack to hold all the components which was then mounted to kitchen drawer slides.



The individual components also slide out to make wiring and replacement simple. each driver also has a 120mm PC fan mounted below for help in cooling. It does get up around 50 deg Celsius in the shed during summer!



Now I needed somewhere to house the PC. As it's width was larger then the depth of cabinet, I grabbed a bit of 1.6mm steel sheet from my pile a bent up a piece to house the PC on top.

[4R8]

After a few cold ones I came up with the design for the top to house the keyboard and 17" touchscreen.



Whilst browsing the local hardware store, I stumbled across a small set of gas struts designed for kitchen cupboard doors that open upwards, strong little buggers!





I'm not 100% happy with their placement and should have spent more time working out where to place them. I'll need to adjust them down the track when 'm working on the controller again.

The electronics below are going to be moved also. They'll be installed into an enclosure on the table itself. Since putting them together, the spark to convert my mill has been reignited. With the computer being mobile, I'll use it for both machines down the track, each machine will need it's own electronics. Also having the electronics on the table itself cuts the cable count between controller and machine from around 8-10 down to 2 or 3.

[f350ca]

Wow thats a lot of electronics and cable. Neat idea having it pull out on drawer slides.

[EdK]

That sure is a sharp looking control center.

Ed

[4R8]

(11-16-2012, 05:10 PM)f350ca Wrote: Wow thats a lot of electronics and cable. Neat idea having it pull out on drawer slides.

It really was a mess before I added the black expandable sleeve.
I'm hoping the new layout in the electrical cabinet will turn out even better.

(11-16-2012, 07:01 PM)EdK Wrote: That sure is a sharp looking control center.

Ed

Thanks bud. You can really dress anything up with Al diamond plate!

[4R8]

Now alot of what I'm doing is "over cooked", mainly to test what I can currently achieve with the tools I have. A rotary table would be nice and would let me do a few things easier and have a better looking final result but I don't yet have one in my possession. One day, one day.

Here's a couple of shots of the belt reduction housings. They use a 15mm wide belt with a 20 & 60 tooth pulley to give a 3:1 reduction.
They use a 12mm hardened shaft through the 60 tooth pulley to the 30 tooth pinion gear.
The side plates are 10mm Al which as usual, is covered in tape to sketch the designs on and save on too many scratches while being thrown around the shop.





this one is designed for the X axis. The Y (currently under construction) is similar in design with a few slight changes to suit their particular location.

Here's where the X unit will sit.



I still need to mill out a pocket in the carriage to allow the unit to go into it's proper location, with the pinion closer to the gantry tube.

Th Y axis, will require one for each side and will be mounted in the following location. Once built, the gantry side plates will need trimming and a pivot point added. The final location will be directly below the gantry





The two plates will be separated with some Al round bar which will be bored and threaded.
Once they're complete, I'll look at adjusting the profile of the pieces to make them a bit easier on the eye. I'm not a fan of the boring, square shape. They just don't look finished.

[EdK]

Those are some good sized stepper motors you're using there.

Ed