[Jcar]

It's a great project. Is it possible to show any pictures after cutting with your machines?

And a few more.

[Jcar]

I was looking at a water below tank but couldn't get it in to a collapsable frame. You must have around 450 lbs of water in that thing, takes some supporting. Sure is pretty though

Thanks for the comments. Actually the table weights right at 500 lbs, and has about 1200 lbs (150 gallons) of water in it. According to the FEA analysis numbers, I get about .080" of sag in the middle of the tank, at the bottom, when it is fully loaded with water. Which is more than acceptable. The entire thing is made out of 10ga (.134") thick steel.

[idaho psycho]

What a vulgar display of raw talent and ability. That is one gorgeous table
and computer set up. I have a plas table that I bought from a friend of mine. But I need to reconfigure the z axis and the controller. It is 96 x 240. Your table encourages me to work on mine, but to take the time and do it correctly as you have. Beautiful work.

[Jcar]

What a vulgar display of raw talent and ability. That is one gorgeous table
and computer set up.

Thanks for the positive comments,

Good luck on your getting your table refitted. I too found the "zone" very inspirational durring the design and construction process.

96 X 240..... Man, that's a big table. I'd love to have something that size. Talk about the ultimate boatbuilding machine. Unfotunately, it would take up 1/4 of my shop floorspace.

[idaho psycho]

Well, I have to admit that a table that size is a floor sucking monster in my shop too. I received the table from a friend of mine for $900.00. The frame rails for the machine are 24 x 7 inch I beam with .680 flange thickness. The flat iron for the top is 2.5 x .250 hrfb every 2 inches. The weight of the table is right around 5500 lbs. I think that Atlas could set the earth on it, if he needed to take a break. It has dual 3/4 inch thompson rail guides on each side to carry the gantry. I really need to get it going, or get it gone. It's too big to be sitting in a shop taking up that much floor space. Have a great day.

[KitC]

Makes a father proud

Great job, Jody.

[samakthachai]

Hi Jcar,
All are very beautiful.The edge of your job is smooth,not slaggy. I think that it may cause from the control of constant height with THC.
Jcar, I would like to request your help. Now,I have some problems with THC300 with connection.I am confused. I am not good at electronic circuit.Could you share the wiring diagram of THC300 correctly? How to connect?.Please have a look my problem from the attachment. :stickpoke


I use hypertherm 1000 for my project.
Cheers
Samak

[Jcar]

Samakthachai,

The THC definately helps with edge quality. The parts that I posted had been cleaned up a little. Either a quick swipe with a right angle grinder, or 30 minutes in the tumbler works great. Prior to clean-up, my cuts have what amounts to about a .015" burr on the under side and a few dribbles of easily removed slag, in tight corners.

As for hooking up your Powermax 1000 to the THC. Take a look at page 3-11 of the following link. https://www.hypertherm.com/library/f...)/804290r1.pdf First you'll need to make sure you have the CNC inteface cable from Hypertherm, that plugs into the back of the machine. This cable has 2 pairs of leads. The green and black leads are connected to "Torch Switch". The red and black leads are connected to "Arc Good".

Now take a look at pages 3-12 and 3-13. You'll need to get some 18 gage or larger insulated wire prefferably in 2 different colors. Run two leads of wire through the strain relief connector beside the CNC interface plug, on the back of the machine. One lead goes to J15 (+ voltage) on the main circuit board and the other lead goes to J16 (- voltage) on the main circuit board. Take the other end of the two leads and connect them to the (+) and (-) connector labeled as "Tip". Make sure you get the polarity correct.

"Torch Earth" connects to your chassis / earth ground. Remember to follow the THC300's instructions http://www.campbelldesigns.com/files...guide-rev2.pdf and keep the sensor boards serial cable shell electircally isolated from your chassis / earth ground.

If nessesary, I can post a few pictures of the connections.

Hope this helps,

[Jcar]

KitC,

Thanks, couldn't have done it without you.

[samakthachai]

Hi Jcar,
Thank for information and your advice. If it's possible,please help to post wiring diagram better than to prevent my wrong connection. :idea:


New hands
Samak

[vcooney]

Hey Jcar,
What type of tumbler do you use? And how meny parts are you able to do at one time? I'm not sure...but did you make a dinosaur?

Vince

[Leeuwinga]

Anyboy looking for a good easy to connect THC system
Based on Mach3?
Go for www.cncdirect.co.za

[thkoutsidthebox]

That looks absolutely FANTASTIC and is a real motivator to get a good finish on my next machine. Very well done. Is it powder coated, or primed and painted?

[Jcar]

What type of tumbler do you use? And how meny parts are you able to do at one time? I'm not sure...but did you make a dinosaur?

I'm not sure of the brand, but it's a .75 cubic foot torroidal bowl. As for how many parts, it really depends on the size of the parts. The bowl is about 24 inches in diameter and 8 inches deep.

Yes it was a dinosaur, I found the .dxf file on the net somewhere. It was a fun little test project.

That looks absolutely FANTASTIC and is a real motivator to get a good finish on my next machine. Very well done. Is it powder coated, or primed and painted?

Thanks, It was primed and painted with an HVLP spray gun.

[Koredova]

Excellent writeup and work on your project. Very well thought out and definitely an inspiration to future builders like myself. I see that you are using NEMA 23 270 oz-in steppers with a 4.29:1 drive ratio for all three axes and I was wondering if you could offer any insight on the choice of this size stepper and ratio as far as the torque and speed are concerned. I am in the process of designing a plasma table and thought that I would need X axis steppers that were larger than a 4.29:1 ratio at 270 oz-in but your project is making me rethink this. The steppers and ratio that you are using are obviously enough but it is hard for me to get a good idea of what speed and torque I will need to adequately move the gantry and why I should choose a certain stepper size and ratio over another. I have read other posts on this topic and some say leave some margin on the stepper size while others say don't use a bigger stepper than you need because they will run hotter than normal. Is .641" of travel for 1 stepper rev a typical number? Also, I really like your idea of making all three drives the same. Thanks again for all the useful info on your project.

[Jcar]

Koredova,

Thanks, I'm glad people are finding my machine and write-up both helpful and inspirational.

As for the motors, I find that 270's work very well with Gecko drives and a 42 volt power supply. I have the Gecko's limiting the current to each motor at 2.8 amps. The higher voltage power supply makes a huge difference in high speed torque. I've experimented with the 270's, an integrated 3 axis driver card, and a 12 volt supply. There was a very noticable decrease in high speed torque (we're talking orders of magnitude here). The Gecko's can manage up to 82 volts and 7 amps, I believe. The motors do get warm (almost too hot to touch), once they've been powered up for a while. However, I'm not getting anywhere close to the maximum operating temperature of 100 degrees C (212 degrees F). They don't sizzle when I spit on them......

I estimate that my total gantry (moving part - XYZ) weight is around 100-120 lbs. It is moved on both sides by a 270 oz motor (540 oz total). If I increase the kernel speed in Mach3, to one of the higher settings, the gantry will rapid at 850 ipm. However, at 850 ipm, you can stall it with your arm and a moderate amount of force. At 450 ipm, I really have to put my body (230 lbs) into it, in order to stall the motors. At 250 ipm and less, I physically can't get the drives to stall. I've set my max rapid speed to 450 ipm, and have experienced no step loss in any of the 3 axis'. If I had it to do over again, I wouldn't change anything. For plasma cutting it works extremely well. It may be different it I were running a 1/2" diameter router bit, 1/2" deep in a sheet of MDF board, at 500 ipm.


As for the drive ratio, I've read anywhere from 3:1 to 6:1. To tell you the truth, I just shot for the middle and got lucky. I suspect that a higher ratio would be better with a heavier gantry, at the expense of top end speed. I feel that the system has more than enough acceleration (very important for plasma work). My system will run at rates higher than 45-50 in/sec/sec. However, the higher values seem a bit "harsh" to my system.

Hope this helps,

Jcar,

[Jcar]

Gentlemen,

I've had several PM requests for drawings of my water table. I'm attaching a PDF file, which contains scans of the 3 layout sheets that I gave to my local steel supplier. I had them shear and bend the parts, while I did all of the welding. Cost for 2 sheets of 5' X 10' 10ga and labor was around $350 ($140 per sheet and $70 labor).

[Jcar]

Here's a DXF file of the slat hangers for the water table.

[totalfab06]

How could I get the original file from Thermal dynamics?

[Jcar]

Totalfab06,

Just Private Message me your email address, and I'll send you a copy.

Jody,