Building a new table, any tips?...

[davek0974]

Slat bed fitted at last, total PITA

IMG_0970s.jpg

Not 100% happy with it as the 50x3mm strip i ordered is a range of anything between 48x3 and 52x3 !
Will be changing it some time soon i think.

I also fixed the warped slat rails very nicely -

IMG_0971s.jpg

A quick slice with a 2mm disc and weld-up, now it sits perfectly flat on the side beams

The vertical weld was also my first vertical-up weld as i'm normally a bench top welder, didn't come out too bad i thought

Stripped it all for paint now, hopefully the weather will be good tomorrow.

[SeanP]

Looking good Dave, like your idea with a single pin on the center rail.

[davek0974]

Looking good Dave, like your idea with a single pin on the center rail.

Yep, seemed like it would do the trick and it does

[davek0974]

Feeling a bit blue today...

Gantry...

IMG_0972s.jpg

Main frame...

IMG_0973s.jpg

Had to repaint the side beams as i forgot to fit the dust shields for the HiWin rails, probably not too important as the blocks have hard scrapers and extra seals fitted on all ends

Now to start rebuilding and final fitting.

[davek0974]

Extract tray / chamber arrived today...

IMG_0974s.jpg

Quality is excellent, glad i outsourced this part

[SeanP]

That looks great!
Just curious,, how much did you say for that Dave?

[davek0974]

The collector was £325 delivered, I could not have made anything like it for that, its fully spot welded, riveted and seam-sealed, the access door opposite the outlet flange is great, it has seals and easy-to-undo twist-locks on it.

In theory the whole lump should just slide into my frame and sit on supports across the base side-rails.

[davek0974]

Coming back together now...

IMG_0975s.jpg

IMG_0976s.jpg

[SeanP]

Your flying! ah you'll slow up from now on
Looking good though, very neat floating z thingy

[davek0974]

Yeah, at present it's just like building a kit - it's pre planned and made, the wiring will slow me a bit but i enjoy that the most.

I expect to be motion testing this week, fingers crossed.

Then i need to clear a space, punch a hole through the wall for the extract, strip the shop out to move it from where it is now to it's final location , and start testing/debugging.

Of course thats if the motion test passes ok, might be building reduction boxes by Friday

[davek0974]

Z axis wiring...

IMG_0977s.jpg

Table wired up...

IMG_0978s.jpg

The timer on the bottom rail is an off-delay of about 20 seconds for my downdraught fan, every cut start and stop triggers the Aux BOB relay and the delay holds the fan on between positioning cycles etc. At the end of the last cut it runs on for the full delay to clear any remaining fumes.

Preliminary panel wiring...

IMG_0979s.jpg

I've got an old BOB laying around and spare PC which i've installed a basic Mach3 setup on, hopefully be able to get the lot tied together this week for motion testing.

[davek0974]

IT Lives

Achieved first motion today, got it lashed up to an old BOB and very poor PC (way below Mach3 specs) and it seems happy, a short video...

https://youtu.be/n34DDnw8org

It was running this file...

IMG_0983s.jpg

Which was the simplest file my mediocre G-Code skills could manually type

Have played with motor tuning and it will go way beyond requirements so pegged it back at my 9000/mm/min target. Acceleration seemed very willing to perform but I'm not sure if the PC is hampering it there or not, its only a 500mhz CPU and Mach is supposed to need 1Ghz or more.

Still, it runs and runs VERY well indeed, smooth, fast and gives me the impression it will work nicely with the torch on.

I have tried to make it lose steps - pushing the Mach "Stop" button when running at 9000mm/min give a very abrupt stop indeed but no lost steps, can't get much more severe than that i think.

Next i need to do some book-speed tests with real cut files and verify the home position after each cut, not even sure its worth doing a pen test - it just seems happy and gives me confidence.

The final step is the tricky one - I need to strip the BOB, THC and plasma from my running table, dismantle that to move it out of the way, move the new machine into position, level it and fit the last parts to it. Then install the extract system, bed frame and slats and start test-cutting. Sounds easy but I know for a fact that as soon as i decommission the running table, jobs will come in!!! The only safe way I think is to put up the "closed" sign for a few days and get it done - we are away in a weeks time for a week so i might just extend the holiday closure period a bit to give me some slack.

Good day today

[SeanP]

Well done Dave, looking really good, good luck with the next stage.

[davek0974]

i can say it was a big relief when I got the final Mach3 settings sorted so the gantry homed on both motors and self-squared That took a few hours to sort out as the old machine only has one motor per axis.

I presume the racks run with a little grease on them?

I might add a guard to the underside of the X-axis rack to stop any splash-back getting into the teeth.

I need to make a 12' hole through the shop wall, It's a sectional build garage so I plan to remove a whole slab/section and make a steel framed replacement and cut the hole in that, that way would make repair easy and as the slabs have steel rebar in them, cutting a hole likely would not work anyway.

[SeanP]

I presume the racks run with a little grease on them?

I just use a bit of engine oil on the racks and the linear bearings.



I need to make a 12' hole through the shop wall, It's a sectional build garage so I plan to remove a whole slab/section and make a steel framed replacement and cut the hole in that, that way would make repair easy and as the slabs have steel rebar in them, cutting a hole likely would not work anyway.

Good idea, you might want to put it back when you move to bigger premises building those tables

[davek0974]

LOL, not sure I'm up to that, although the second one would be much easier now.

So far there are only a couple of things I would do differently which is good, having a long list of those is not a good thing in my book.

Still worried about that odd bevel issue though and the THC setup, What speed does your Z run at and what THC rate/% do you use??

[SeanP]

THC Rate is 28%
Span gap 4/4
4000mm/min Vel
1000 acc
Seems to work well for most material.

I did see your shots of the ally with bevel, hard to say really, I haven't really cut much ally, I do get a bit of that going on with steel on some intricate parts, nothing like 45° though.

[davek0974]

Made the replacement wall panel today, fitted the extract fan to it...

IMG_0984s.jpg

This should replace one of the slabs in the garage wall directly, hopefully be able to undo the two bolts, pull the slab inwards and replace with this one.

The fan is connected to the table via a short length of 12" flexi ducting. Its controlled from my G-code, have altered the post processor to put the on/off codes where i want them.

I'm off for a weeks holiday now, plan is to move the table into position as soon as i return

[davek0974]

Back from a way too short holiday Stripped the workshop out and moved the new table into final position...

IMG_0994s.jpg

IMG_0995s.jpg

The extract fan panel fitted perfectly, but shifting that volume of air turns out to be damn noisy, i can probably expect trouble from the neighbours i think, will have to be careful when i choose to do my cutting

Finishing off the panel now, fitting the BOB boards and wiring them in, then i need to build something to hold the monitor and keyboard etc, some sort of workstation.

Then i have to puttee workshop back together again

[muzza]

Looking good Dave, not sure if you can do it or not but if you turn your slat holing frame 90 degrees it will make it much easier to load material from the front. The material will slide a lot easier along the slats rather than across them especially once you get a bit of dross on them.
Murray

[davek0974]

Thats an idea, thanks.

I was thinking of sliding big stuff on some small pipe or rods but your idea might be just as good.

[acourtjester]

2 of my controllers complete with PC inside a single case.

4 X 8 table (10).jpg

finished table (1).JPG

and the start of a newer one

DSCN1592.JPG

DSCN1600.JPG

[exapprentice]

Hi Dave
just noticed in one of your pic's, is that a consumer unit mounted on your wall behind your table?
if it is, how do you keep the P Dust out or is it a sealed type??

regards
exapprentice

[davek0974]

2 of my controllers complete with PC inside a single case.

Wow, that is a nice setup.

I have the controller and drives in the chassis cabinet so all i need to lose is the pc, keyboard and monitor.

I like the swing-out idea might borrow that one

I was thinking of stripping the pc and mounting it all in the control cab but was advised it was not a good idea for reasons of shielding the main board etc - do you get any issues from having it all in one box????

[davek0974]

Hi Dave
just noticed in one of your pic's, is that a consumer unit mounted on your wall behind your table?
if it is, how do you keep the P Dust out or is it a sealed type??

regards
exapprentice

Hi

yes it is but its on the opposite side of the room to the plasma, it did have a lathe in front of once and has been covered in cast iron dust and swarf - didn't seem to bother it. The important bit is to make sure there are no holes in the top panel or sides. The plastic flap protects the mcb's.