MY 4`x 4` table [Archive]

Steve-m

08-09-2008, 09:51 PM

HI All

I will start my build log with a repeate of my introduce your self post, I'm sorry to those who read it but those who didn't this is self explanatory.

my project is a 4`x 4` plasma table, at the moment I have the Bridge 75% complete with a home made Z axis with 150mm of travel with a Trapezoidal lead screw, and a 3Nm stepper. A 1.4mtr, 25mm linear rail Y axis with a 1mod gear rack and pinion, also with a 3Nm stepper. the X will be 10 cam follower bearings running on and guided by 75x12 cold rolled steel, driven by 2 off 3Nm steppers, one each side. all designed in Auto CAD. the plasma unit is a Thermal Dynamics 75xl with a capacity of 20mm. I dont have any electronics yet, other than a PC with Mach3 on it, I am hoping to get a Candcnc torch head control from America, these are some of the earlier pictures, tomorrow I will take some fresh ones, unfortunately things have come to a temporary stop, I burnt the motor on my miller, The fan stopped working and I cooked it drilling the gear racks for the "X"

http://i163.photobucket.com/albums/t311/lleskam/bits.jpg

http://i163.photobucket.com/albums/t311/lleskam/plasma.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0420.jpg

I hope this is of interest to some

Looking forward to hearing your comments and advise

Steve

Steve-m

08-09-2008, 09:55 PM

Here are a few more pictures

http://i163.photobucket.com/albums/t311/lleskam/DSCF0419.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0421.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0422.jpg

Robin Hewitt

09-09-2008, 11:08 AM

Interesting, I think the design philosophy is that you know it's going to bend like a banana with the welding but everything adjusts on slots so you can compensate. It may weigh a ton but you have overpowered it to overcome that? :D

I think it will work well. Not sure you can pierce thick plate without angling in but you can always start from an edge or a pre-drilled hole.

I'm just doing the circuit boards for mine. I went for a solid iron bed with a lightweight aluminium gantry, but that's just me.

Problem is you really need a CNC plasma cutter to make the plates that hold the bed rails. I may just fudge the bed then cut them.

I think THC is fairly simple but hyped up as difficult so they can sell you the kit. If you buy kit you are stuck with whatever output they choose to give you and you rely on them to sort out your problems remotely. I like to feel in control even when I'm not :D

I want to get an oscilloscope on the torch volts and move it up and down a bit, see what there is to work with. I don't have an 'arc good' output so I need to detect the HV igniter sparks when the main arc fails.

The bit that still concerns me is setting to the pierce height on thin plate. I drop down on to the sheet until it takes the weight of the torch the back up. BUT, suppose it bent under the weight of the torch and then followed it up? You may think you are lifting when you actually aren't. I was thinking maybe fire a 40v spark down through the tip and see if it goes, but maybe that's over-egging the pudding.

m_c

09-09-2008, 03:49 PM

THC does sound quite simple in theory, but I'm guessing it's more complicated than what it first seems.

Basically you need to know when the plasma is active, so you can then measure the torch voltage (doesn't campbell's use a suitable placed inductor, rather than direct monitoring?), smooth that voltage/signal to remove spikes/dips, then compare that to a reference voltage. Then depending on voltage, either signal the torch to be moved up (increase voltage) or down (decrease voltage).

Sounds quite simple, and I'm sure you could design a crude set-up to move the torch up/down, but getting something on the level of one of the commercial/pro-hobby boards would take quite a bit of work.
Would certainly be an interesting project for someone with the electronics know-how...

Robin Hewitt

09-09-2008, 05:42 PM

As I understand it...

1: Drop the torch till it touches metal.

2: Back off to pierce height

3: Establish an arc, wait for the pierce

4: Drop down to cut height and start moving X Y

5: After a short movement, measure the volts and save that as the benchmark.

For torch height I used 4mm studding with a 2:1 reduction pulley off a zippy DC motor. There is a chopper disk on the motor shaft for initial position and a digital voltage regulator to control the speed. I plan to measure the torch voltage many times a second then switch the motor speed/direction/brake accordingly. Not much of a plan but it's all I've got :D

Steve-m

09-09-2008, 08:38 PM

Hi

Well Robin the idea originally was bolt together aluminium 60 x 60 for the bridge, that's what all the holes are for in the plates, I can change at a later date, every thing is only bolted. I rang some one in Yorkshire abut some they said they had it in stock, I drove 150 miles there one way, only to be told sorry they made a mistake, I said ****** ***** **** off! and made it in steel.

I plan on making the table then setting the whole thing up with a dumpy laser level and shims, the bridge bowed when I welded it but only by .02mm, I set it up on the mill put the center bolt in the linear rail and a DTI in the chuck and clocked it parallel then bolted it, I then assembled the Z upright, put the DTI on that and clocked the gear rack 2 ways so that's parallel to the rail. all the slots are for setting up gear racks and reduction belt adjustment, I may pivot the motor and belt plate on springs to "track" the gear rack if I have problems

As for cutting thick material, I mostly want 5-6mm occasionally 10mm, so I have plenty of spare capacity, its not for work only another tool for my "Play pen"

My plasma has all the CNC connections on a plug already, "okay to move" "torch on" "power" and dose not have the HF start, so no damaging spikes, Its real strange it will fire in the air, and with out the earth it will gouge 10mm plate 4mm deep ( I could not work out why it would not cut, DOH!!) I can also touch cut at full power, 60A, running the shroud tip directly on metal, so it is possible to simply rest it on the metal and drag

Unfortunately electronics and I dont get on, Im colour blind and resistors are a nightmare, so I dont do any circuit boards at all, unless its plug and play. I played with a osiloscope, when I did my degree, no matter how hard I tried I could not find ITV and the picture was rubbish all spikes and wavy lines, and it was so small LOL

Steve

Steve-m

10-09-2008, 07:54 PM

Hi all
here are a feww pictures I took today,

http://i163.photobucket.com/albums/t311/lleskam/DSCF0649.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0644.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0642.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0650.jpg

Your coments and views will be apreciated

Steve

m_c

10-09-2008, 09:16 PM

Looking good.

I've got a copper/boxwood hammer that looks very similar to yours, although mine's a little bit more (ab)used looking than yours :-)

Steve-m

10-09-2008, 09:23 PM

AHH Mine is a copper - leather one, You want to buy a not as abused as yours mallet???

I also seem to have a collection of ball pane hammers, Im sure the buggers are breeding when Im not looking today, there was 9 of them, and they were all out of the draw at the same time

LOL

Steve

Lee Roberts

11-09-2008, 11:13 AM

Looking good steve, keep the pics coming !

The rail mounts on your Round Rails, did you make them yourself ?

Steve-m

11-09-2008, 07:32 PM

Looking good steve, keep the pics coming !

The rail mounts on your Round Rails, did you make them yourself ?

Hi Lee

would love to say yes but I bought them from Merchant Dice, had I looked harder at them first I would have made them, but I didnt, as you can see Im in the middle of making the carrage to go on the bearings on the rails. My new boring head should be here tomorrow, the old one seems to have grown legs and run off to join all my snap on tools from over the years,

Steve

Lee Roberts

11-09-2008, 11:05 PM

Yea i wondered if that was the case, looking forward to reading your build log mate. Cant beat seeing people making their own gear/kit for the cnc's.

Robin Hewitt

12-09-2008, 11:52 AM

Steve-m

12-09-2008, 07:27 PM

Have you got any thoughts on painting it yet?

I keep resisting the temptation to waft Ambersil over the exposed iron on mine hoping a miracle paint will show up. Can't stove it, can't find epoxy paint.

It looks sturdy enough, perhaps you might christen it The Bismark :D

Paint, Paint, you seem to think I already have enough weight, well I didnt want some flimsy bolted together jobbie, I want it to stop from full speed without ratteling around, I also want to put a milling head and a router on it so it needs to be sturdy, so it was all tig welded

I have a electrostatic spray gun so I may just put smooth hammerite on it, or there again if I think I have enough power in the motors and they will take the extra weight, I may just have it powder coated

Steve-m

14-09-2008, 04:15 PM

Hi All

Well the fruits of this weekends work my "Z" axis, just have to put the top bearings in, mount the motor, and Roberts your Fathers brother!! a finished "Z"

Steve

http://i163.photobucket.com/albums/t311/lleskam/DSCF0661.jpg

Lee Roberts

14-09-2008, 06:49 PM

and Roberts your Fathers brother!!

Well i say, BRAVO! that looks nice steve.

How did you "lock" the bearing units in place? also any chance of some close up pics of that unit.

Steve-m

14-09-2008, 07:11 PM

Hi Lee

Well, od of bearings 26mm milled holes to 25.90 ish, warmed housing and dropped them in and cooled quick. the table saw dose come in handy sometimes as a big cold lump of cast iron, there not going any where in a hurry, I can knock them out if I ever kill them, and sweat new ones in, I miss judged the lead screw nut a bit it needed a bit of help from a plastic mallet!!

will get some pics tomorrow when I go to the play pen

Steve

Lee Roberts

14-09-2008, 11:01 PM

Dont worrie about the pics mate i can see the pic above ok now, i'v just sent you x2 PM to read :).

Steve-m

18-09-2008, 07:18 PM

HI

had a day off so played all daythis is where I got to,

http://i163.photobucket.com/albums/t311/lleskam/DSCF0677.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0678.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0685.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0687.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0688.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0689.jpg

Todays deliberate mistake!!

http://i163.photobucket.com/albums/t311/lleskam/DSCF0682.jpg

and what a cock up it was

Steve

Lee Roberts

18-09-2008, 08:08 PM

and what a cock up it was

Steve

What you going to do just swap it for a (button-head) screw?

If you need any let me know via PM ill sort you out what you need, i'v got most lenths/sizes, stainless, zinc, black.

If you give me the size's also, how much "head" room have you got?

Steve-m

18-09-2008, 08:22 PM

What you going to do just swap it for a button-head screw

Hi Lee

If you look at the second to last pic you will see I solved it by milling counterbores into the rack, I was going to put button heads in it but decided to counter bore instead

Steve

Lee Roberts

18-09-2008, 09:54 PM

AMEN! to the Counterbores, i got that one you showed me on the bay cant waiti to try it out!

Steve-m

19-09-2008, 06:20 PM

Had some more spare time today so I hacked a torch mount out of a chunk of solid Aluminium, It made me realise that I will have to make a 300mm dropper plate, any how heres the pics

http://i163.photobucket.com/albums/t311/lleskam/DSCF0691.jpg

and just to show the torch fits I tried that in as well

http://i163.photobucket.com/albums/t311/lleskam/DSCF0690.jpg

Lee Roberts

19-09-2008, 08:03 PM

Steve-m

19-09-2008, 08:48 PM

Hi steve, looking good mate !

Yea all the machines i'v looked at have got a plate that your talking about for the spindle mount to then fix to. Looks nice tho mate nice one, i managed to get a some more done on my rockcliff tonight will post up the bits later.

Them flanged bronze (?) drive nuts you have used, where did you get them from? also did you say they are just droped in once the ali block has been heated up ?

Hi Lee

Im starting to get real fed up with tapping holes though, that seems to take for ever by hand, I could use the drill but I dont like doing that.

not quite.... I bought the wrong nut from Merchant Dice, I machined it down to 20mm od and cut the top hat part off so it was just a round bit about 25mm long with a thread down the middle, then I bored the ali block on the miller to fit........nearly

have got a piece of ally on its way from ebay 100mm wide, 10mm thick and 300mm long, £10 not bad.

need 2 more steppers but they will have to wait a week or so, "ER" is starting to moan

Send me a link to your rockcliff please,

Steve

Steve-m

23-09-2008, 05:52 PM

Hi All

decision made!! There is no going back now "Z" finished apart from a small second floating "Z" to get hight, I have drilled and tapped botom of "Dropper" plate to take a tool holder so I can use table as a router as well by sliding second "Z" up and bolting tool holder on.

http://i163.photobucket.com/albums/t311/lleskam/DSCF0698.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0699.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0700.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0701.jpg

Steve

Steve-m

01-10-2008, 08:06 PM

Just a quick update, finished floating "Z" ready for THC, Luckily Jim Cullins from soundlogicus.com will still ship one to England along with a breakout board from Rob Cambell will make a good combination, I hope.

http://i163.photobucket.com/albums/t311/lleskam/DSCF0714.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0716.jpg

Lee Roberts

02-10-2008, 07:27 AM

Looking good mate !

Robin Hewitt

02-10-2008, 10:05 AM

Steve-m

02-10-2008, 10:27 AM

A floating z axis, so you're going to use the 3 ball arrangement to set the torch height. It does sound heaps easier than faffing about measuring the volts. This could be up and running PDQ.

Looking good. We'll need a movie when you get it cutting :D

Hi Robin

actualy no Im not going down that balls route, the idea is to put a limit switch on floating "Z" and use as a ref, bring "Z" down torch will touch metal and lift floating "Z" into ref switch, and stop then lift "Z" by a known amount (switch travel + clearance of tip) and fire, this way every start will be automaticly set to differing thicknesses of material, as the distance of lift will be a constant. well thats the plan, Mach3 has this ability

Steve

Steve-m

25-10-2008, 08:28 PM

Hi all
Just a bit of a update, I have spent a few weeks collecting bits for the controller, and this is what I have, Campbell Designs excelent Break out board, a Sound Logic Power board with a 500va transformer together they give me 50v dc, and Gecko G203 Vampire drives (Im still 2 short but funds allowing I will order those this week), all in a 2U rackmount case with power and E Stop on front and all plugs on back

Steve

http://i163.photobucket.com/albums/t311/lleskam/DSCF0746.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0745.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0744.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0743.jpg

Steve-m

25-10-2008, 09:45 PM

Looks like a good plasma table :beer: Not sure how it will work out as a router with the single bearing on the Y axis...Either way some good quality work you've done so far!

Thanks for the support, its nice to know people out there are interested

Im not even sure I want wood near it I dont do wood well, you cant weld a bit back on when you make a cock up, but it dose keep you warm, providing it will fit in the wood burne, but I may just try it out, but on the whole not realy bothered, I do have room on the back or under the gantry for a second rail but only if I realy need one, Buying the first made my eyes water

Steve

Steve-m

26-10-2008, 08:25 AM

:eek: Thats some amount of money! you can probably add the same again for bearings, and the same again for a controler setup all without the cost of the frame. When you think about it these things can seriously harm your wealth! and mine is going to be just a toy! :D

Steve

Steve-m

26-10-2008, 12:48 PM

It is indeed! I have £800 of junk sat on a shelf...it's a useless 4 axis controller.....We live and learn.

That was the reason I decided to build mine myself from well known parts, my motors are 4.5a so I needed large drivers and gechos 203`s are suposed to be one of the best, the Vampire has a nice trick with microstepping and speed it morphs out of microstep, together with the power board and BOB were all designed to work together, all I had to do was find a case and transformer then spend a day wiring it all, hopefully I still have enough room be it on a second layer to get Jim Cullins THC in I did want a CandCNC one that included the Torch Head Control and BOB all in one, but they did not want to send to England something about lead content

Steve

Steve-m

26-10-2008, 02:38 PM

I actually bought mine ready assembled from a manufacturer....We do indeed live and learn :D

I nearly bought one from ebay but for som reason decided against it, propably money, to spend that sort of cash in one go would upset me too much.
can nothing be done with it to make it work for you?? resell it on ebay it must still have a value to someone

Steve

irving2008

26-10-2008, 03:43 PM

It is indeed! I have £800 of junk sat on a shelf...it's a useless 4 axis controller.....We live and learn.
whats wrong with it Kip?

irving2008

27-10-2008, 12:29 AM

It needs the power stages replacing (L6203 IC's) I have them but kind of wrote the unit off as a loss....Nice stainless case though!

Thinking of flogging it? Assuming its fixable...

Steve-m

27-10-2008, 08:09 AM

We've stolen the thread from Steve too :D

That's Ok Gents, not a problem you carry on. I haven't been watching, trying to get to grips with Mach3, In the words of Homer Simpson "Every time I learn something new something I already knew disappears" must be a age thing

Steve

Steve-m

27-10-2008, 11:42 PM

What are you wanting Mach to do Steve?
Hi Kip

I`m trying to learn it, I seem to have some problems with my setup, but I don't know what I have done, this is my first play with cnc of any kind, ever so I'm a complete novice

1/ when I REF ALL HOME it hits the first switch ( all 3 are the same switch on each axis ) reverses off and ESTOPS!

2/ unless I change the % value in soft limits to 100% I can only get 20% speed

I have copied Bobs xml for the break out board, step by step manually into mach3 plasma. I think its in homing - limits my table is 1250mm square A & X are slaved, so soft max = 1250, soft min = 0, slow zone = 25, home off = 0.00 for X,Y,A and soft max = 0.00, soft min = -140, slow zone = 12, home off = 0.00 for Z

motor = 159.154 steps per, 10000 velocity, 1250 acceleration,

If you can help You will be My hero, I have fought with this for near a month, I have asked on most of the forums, and never got a reply,

Any body else any ideas??

Thank you in anticipation,

Steve

Steve-m

29-10-2008, 08:28 PM

You could try copying then pasting the xml file into the Mach folder, then using the Mach Loader to select it.

The manual seems quite clear on how to set it up...start on page 10 (I've never used them so haven't had to figure them out) I may have to soon...If I ever get around to the router :D

Forum attachment size for a .zip is 97k so I can't attach the manual :(

Available here Mach3 setup tutorial (ftp://machsupport.com/Docs/)

Have a good nose around on the ftp site...there's lots of interesting things there!

Hi

Done all that, including watching the videos, but im still missing something, I just dont seem to be able to get soft limits to work the "X" insists in hitting the switch at full speed

Steve

Steve-m

11-11-2008, 07:50 PM

Well yesterday I stripped it down and painted it in Blue smooth Hammerite, turned the heater on it and left it to cook for a few hours, then came back this morning and put another coat on it and cooked it again then spent the rest of the day putting it back together. I managed to get the gear rack to within .04mm that works out to about 0.0015" from one end to the other and all bolt points in the middle on my DTI off the linear rail carriage.

I have finally got it moving at 10,000mm a min, soft limits are fine it stops at 1299.997mm on the DRO, the setting is 1230mm. I do still have a small problem, the "Slow Zone" dose not seem to be working, It goes from full speed to stop instantly, I will have to look into it and see what I have done wrong

Well Robin I had to make it even heavier, but I just could not leave it so I took it up to the old workshop and got it nice and warm and hit it with hammerite smooth blue

Its time to start making the base table now, Hopefully the other 2 Geckos are on there way and I still need to order 2 more motor

a short Video of it moving

http://s163.photobucket.com/albums/t311/lleskam/?action=view&current=DSCF0790.flv

http://i163.photobucket.com/albums/t311/lleskam/DSCF0781.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0780.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0781.jpg

http://i163.photobucket.com/albums/t311/lleskam/DSCF0775.jpg

Lee Roberts

11-11-2008, 08:46 PM

Very nice mate ! i wish i had the kinda space you'v got !

Steve-m

11-11-2008, 09:04 PM

Very nice mate ! i wish i had the kinda space you'v got !

Thanks Lee, not my place, the buildings and grounds belong to My Friend, I just have free run of it all, its my workshop, in return for helping him out now and again, it works both ways, for both of us,
The pics where I painted it was my old workshop, before it moved to the new building, its a bit big 5000 Sq Ft, the workshop is about 1000 Sq Ft and colder than the old one

Steve

Steve-m

07-12-2008, 07:53 PM

Hi All

Just a quick update, I have started on the table ( will get some pictures tomorrow ) for reasons beyond my control I have made it into a 6`x 4` table, I had 2 off 2Mtr gear racks for the X - A axis and had to buy the cold rolled steel for the runners in 3Mtr lengths so rather than cut a good bit off them and waste it I had another look at the cad drawings and managed to get a 2.5Mtr length table with 1950mm travel in the X-A and 1220mm in the Y from the material I had, from 2 full lengths of 7.5Mtr of 60x60x3 box I only had 2 pieces 40mm long scrap, but I do need to buy another length of something to carry the material supports and the water trough ( if I fit one)
But standing in the workshop it looks big, and I have yet to put caster on it

Steve

Steve-m

29-12-2008, 04:09 PM

Happy Chrismas and a prosperous New Year to all

just a few pictures for those interested, 4`x 4` taple turned into a 6` x 4` table for no extra cost, I did hope to get the 3"x1/2" Bright bar (coled rolled) for the "X" runners before Christmas but missed the stockholders they closed early, so still need to get them yet.but this is how it should sit, I will put jacks on the corners eventualy, when I work out how or even what I want, Any one any ideas??

The control box is now finished for 4 axis and works well I still need to get a THC from Jim Cullins at Sound Logic, and 2 more motors for "X" then I can mount gear racks, slatted bed, and "Roberts your Fathers brother!" finished play time begins..... oh and of course PAINT it blue

did try to upload more photos but after emailing them to my self 4 times to reduce size I still cant get some of them small enough, sorry.

all the best

Steve

irving2008

29-12-2008, 04:32 PM

... did try to upload more photos but after emailing them to my self 4 times to reduce size I still cant get some of them small enough, sorry.
...
Steve

Download a copy of GIMP (http://gimp-win.sourceforge.net/stable.html), this will allow you to resize/recompress pics and a whole lot more...

or download any number of of shareware jpeg image resizing/compression tools... which will allow you to select the appropriate image size & compression setting (typically 50% or better) to reduce file size

Steve-m

29-12-2008, 04:47 PM

Hi

Thanks I did have microsofts Power toys in xp but in vista the only way I found was to email them to myself, will try them cheers

Steve

Lee Roberts

30-12-2008, 07:59 AM

Looking good steve, cant wait to see it in paint.

"Roberts your Fathers brother!" uncle is that you ?, i have a Father ? :D

Ill have a look at the image upload spec's for the forums and the gallery and so on, i'm postive i have set "no limit" to image size in terms of the file size.

Lee Roberts

30-12-2008, 08:13 AM

Hi guys take a look here:

http://www.mycncuk.com/forums/showthread.php?p=2273#post2273

Steve-m

30-12-2008, 11:44 PM

"Roberts your Fathers brother!" uncle is that you ?, i have a Father ?

Ah but can you prove it, we only have your word for it Lee,

How did that pic get in there?:eek: she said she would not show it, I have said it before never trust them!!;)

Steve

Steve-m

31-12-2008, 09:55 AM

HI All

one other thing I am planning is a Bluetooth keyboard, to use as a remote pendant, there is a Keysonic with a laptop style mouse pad on Ebay for £35, unsure yet weather to take it apart and just use the "Hot keys" for Mach3 as buttons in a hand held unit, or just leave it as a keyboard,

I like the idea of a wireless pendant the only problem is I will need 2 because I will probably loose 1

there is another pendant I like around also on ebay but in the US but its not a wireless one
if any one has any views on the Bluetooth I would like to hear

Cheers

Steve

Yet again Im sorry it womt let me put up pictures as atachments (I could put pn photobucket adn link to them but I cant remember my password at moment) despite shrinking them as much as I can, it says.
PLASMAPenVer3.jpg:
The Dimension limits for this filetype are 620 x 280. We were unable to resize your file so you will need to do so manually and upload it again. Your file is currently 454 x 480.

BillTodd

31-12-2008, 04:26 PM

did try to upload more photos but after emailing them to my self 4 times to reduce size I still cant get some of them small enough, sorry.

You can download Serif PhotoPlus 6 (http://www.freeserifsoftware.com/) for free here (http://www.freeserifsoftware.com/) . It has an excellent export picture option that can resize and re-compress your images with ease, as well as all the usual photo manipulation tools. I'm using Serif PhotoPlus 11 but there are probably versions 12 and 13 (X2 and X3) available by now.

Steve-m

04-03-2009, 10:54 PM

Hi all

sorry for the delay in posting pictures, cold weather, hospital, and just plain old lazyness, preventen me from taking them before.

any how this is where Im up to, any coments or questions please go ahead I like to know im not talking to my self

progomez

05-03-2009, 02:22 AM

[FONT=Arial][SIZE=2][FONT=Times New Roman][SIZE=3]HI All

one other thing I am planning is a Bluetooth keyboard, to use as a remote pendant, t

I wouldnt use bluetooth myself as Im using 2.4ghz microsoft keyboard and mouse which sometimes prevents multiple keypresses, hence my motors stop when I jog them. Better to use wired.

Hi all

sorry for the delay in posting pictures, cold weather, hospital, and just plain old lazyness, preventen me from taking them before.

Great pictures and a solid machine. What stops the gantry lifting as I cant see bearing underneath? Is it the weight?

Ignore last comment as just realised this is the plasma section

Lee Roberts

05-03-2009, 04:44 AM

Looking good to me, cant wait to see this baby "spark" to life !

Steve-m

05-03-2009, 07:41 AM

Great pictures and a solid machine. What stops the gantry lifting as I cant see bearing underneath? Is it the weight?

HI

Thanks for the comment, good point there just not fitted yet, nor are the end stops, its still work in progress, Im still 2 motors short, I did order some but when they came I realised I had ordered the wrong ones,

Steve

Smiler

06-03-2009, 08:09 PM

Steve-m

07-03-2009, 01:07 AM

Hi Steve,

would you not have been better off mounting the rack and pinion the other way up to keep dross off it?
(or are my eyes in upside down again):p

that would aslo have stopped the gantry rising

Jeff

Yes it would have been But when I did it it got in the way of the under side (anti lift) cam followers (not fitted in pictures) but in hind sight had I mounted them the other way up I would not have needed the followers, there is still time to have a rethink yet, but put a single motor on the "X" today on the one side only and it runs sweet as a nut, it traveled the 1.9 mtr in 13 seconds fast travel no binding or high spots..........what do I do????????

Steve

Lee Roberts

17-05-2009, 05:58 AM

Hi Steve, any updates for me on this build ?

Lee Roberts

18-05-2009, 01:54 AM

Hi Steve,
Could you or anyone reading this please tell me what those green plug type things are that you have used on your machine?

I'v seena site selling "Hole Plugs" in the usa but i was after the proper name for them and also a source in the UK if anyone knows ?

Steve-m

28-05-2010, 10:01 PM

Hi all
well has it been more than a year since i touched plasma table, well now warm weather is hear and im on mend perhaps this year will see it finished, if i can remember what im doing.

Steve

Bloodaxe

06-10-2010, 02:20 PM

Hi all
well has it been more than a year since i touched plasma table, well now warm weather is hear and im on mend perhaps this year will see it finished, if i can remember what im doing.

Steve

On the mend? Hope it wasn't too serious....

All the Best, Oz.

AdCNC

14-01-2011, 03:27 PM

Web Goblin

14-01-2011, 11:11 PM

For your Initial Height Sensing (IHS) you can use a simple touch and retract system. This consists of a small linear bearing inside the torch holder bracket. The rail will be about 15mm longer than the bearing. The drive system connected to the rail and the torch holder connected to the bearing. Mount a small limit switch above the bearing. When the torch goes down to hit the plate the height motor continues to drive down until the bearing "lifts" and activates the switch. This is your bottom height sense. You can then use a simple adjustable timer to time the retract lift to get the correct height. The 20mm round type timers that adjust via the front dial are good for this.
Normal arc loss in detected by usng a hall sensor which is basically a current clamp. This is normally locked out for a small time to allow the arc to be established.
Normal arc start is as follows:
Gas flow on.
High frequency on.
Pilot arc.
Arc current flow is detected by the controller then it ramps up the current to the set value.
Arc height control is normally done via a voltage divider which measures the arc voltage. As the torch height increase from the plate the arc voltage rises and so does the output from the divider. The Arc Voltage Control (AVC) then sees the rise in voltage then signals the head drive to lower the torch towards the plate till the set voltage is reached. Same idea if the torch goes down towards the plate. The AVC normally locks the height control at a set distance before and after corners normally around 25mm. This prevents the torch movement as the drive slows down to take the corner then accelerates away from the corner.
As for piercing plate a normal lead in value is around 1.5 to 2 times the thickness of the plate so for 10mm thick the leadin would be 15 to 20mm.

Regards

Ian

coldrain

19-01-2011, 10:07 PM

Hi Steve
Fine workmanship, i'm thinking along the same lines myself, although i really need a 8 x 4 table, can you tell me where you got the electronic gubins from. Sorry the engineering bit comes easy, it's the electronics that get my knickers in a twist.

ukracer

30-10-2012, 12:07 AM