Monday, December 14, 2009

Gianttech Plasma Cutter

As mentioned in the previous post, I have bought a plasma cutter a short while ago from the good folks at Since I only have 110 service in the garage, I had to opt for the Cut40D model (which is confusingly called the Slice40D on the face of the unit). This model features auto-switching between 110 and 220. It comes with a 220 plug on the end, but it is easy enough to switch it for a 110 style plug. I opted for the 110 20 AMP style plug.

All in all, it is a very good study unit. It slices through sheet metal like it isn't even there and so far does fine up to at least 1/4" mild steel. I haven't yet tried it out on thicker stock, but I'm not sure if it could go to a full 1/2" or not. Most of my projects are with 1/8" angle iron stock and it blasts through that with no problem. Like welding, you need to watch the safety precautions and it takes some practise to make steady cuts - especially straight lines.

The Gianttech folks I bought the unit off of were very helpful, however shipping up here to Canada took quite a while, but as a hobbyist I wasn't in a huge hurry. I also bought the package of extra consumables available for the unit since I read that these can be used up quickly. I have had to change the tip once, but I think that is because I fried it when I was learning how to use the unit. Now that I have more practise, I am not noticing much deterioration of the tip or other consumables.

I also had to upgrade my air compressor to an 8 gallon 2+ HP unit. I ended up buy this unit from Boss Tools. It is a very sturdy compressor that seems to deliver loads of pressure! While the Cut40D comes with a combination air regulator and filter, on the advice of my welding teacher, I also added in an extra filter (this item). Apparently, the drier and cleaner the air, the better the cutting and the longer the consumables will last.

Here is a quick video of the cutter in action (note that I keep calling it the "Slice40D" since that is what the face of the unit says):

I only had a couple of small issues with the unit. Like many Chinese tools, the manual was laughably short. My Lincoln Electric MIG welder came with an encyclopedia compared to the Gianttech cutter! However, what was there was adequate to get started.

Another issue was that I initially got a lot of air leakage from the hoses connecting the regulator/filter unit to the cutter. First, I replaced the hose clamps and that mostly fixed it, then I replaced the 1/4" NPT-hose barb fitting off of the regulator and that fixed it. Again, pretty small stuff, and I suppose typical of the small "fit and finish" items you find on Chinese tools (my lathe & milling machine also needed minor tweaks). For the money, I am frankly amazed with how well it works. If I were running a full welding shop, I would probably opt for a heavy duty Miller machine or something, but for a "weekend warrior" hobbyist like me it works great!

Plasma Cutting Table

Plasma Cutting Table

Maintaining my blistering pace of a posting every month or so, here is another project write-up along the metal working lines. I recently bought a Gianttech plasma cutter from the good people at (which I will post about shortly). It became obvious pretty quickly that just cutting things on the edge of the welding table wouldn't work very well - and risked damaging my beautiful 3/16 steel top for the welding table. So, the answer was to build a simple plasma cutting table.

At it's most basic, a plasma cutting table is just a set of steel slats turned on their end that conduct electricity to the workpiece, but won't interfere with the cutting action because of their thin profile. I decided that the most reasonable design was to go for 1 1/5" slats of 1/8" thick mild steel. I also figured that the grating part of the table would take a lot of abuse from cutting so it would be good to make it so it could be easily turned over and eventually replaced. The basic idea then was to build the grate as one unit, then have it be able to be set onto the base frame to make the completed table. The base frame is made from good ol' 1 1/2" x 1/8" angle iron. The table surface area is 2' x 2'.

The first parts that I made (which I didn't take pictures of) were two angle iron squares. One makes up the top frame and the other is the cross brace for the legs.

Here is the construction process for the grate - I just used corner clamps to keep adding in more and more slats. They are positioned just slightly over 1 1/2" apart so they space out evenly:

When it was done - and with a bit of grinding and fitting - the grate fit perfectly into the top frame:

Here are the grate, squares and legs waiting for assembly:

...and here is the completed unit:

Ah, the astute observer will notice, why isn't the grate nestled neatly in the top frame the way it was designed? Because i managed to weld it together upside down! Arrgghh! Another lesson that WELDING IS PERMANENT! Double check everything before reaching for the welding gun. However, I was able to weld some extra angle iron onto the top frame to hold the grate. So, it ends up being an inch or so higher than I might have liked, but otherwise is very usable and the top is still easily replaceable:

It's all stores up nice and compact and when I need to work, I can just swing the welder and cutter out on their trolley.