Welding Tips and Tricks

Here are a couple of welding tables.

This one I welded from scratch. The vice goes in the stand in my previous projects thread.



This one was a base to an oven at my previous employer in Ga. I added the top, wheels and riser legs. Even with the drillpress this table is great for sitdown work on small parts. You will also notice a ground wire wrapped up on this table (you can see the wire passing thru the bottom tube) and on the one in the background. I did this before I extended the ground on my HTP 221 welder.....it also works to ground my plasma cutter!



I tend to go against the norm on some things...........case in point this bottle holder for my argon. None of my TIG machines (3 in all) are on carts. Two have 25 ft. torch hoses (with ground extensions) and one has a 12 ft. hose. You will notice I have a spliiter valve on this bottle and quick connects. I also have a 50 ft. hose and a quick connect on my Lincoln MIG welder for running a spoolgun !

I can't build my tables and fixtures that nice...

I'd never let myself use them.

Rah, what size bottle is that? 80 cf? I have an oportunity to get a 55 cf for 75 bucks. The 80's are $220 filled. I probably won't do alot of mig welding.

CraigLam wrote:Rah, what size bottle is that? 80 cf? I have an oportunity to get a 55 cf for 75 bucks. The 80's are $220 filled. I probably won't do alot of mig welding.

Yep.............that is an 80............straight Argon cost me $47 to fill........bottle and all is around the price you have above !!!

I was looking to purchase a larger Argon cylinder last week in Calgary for my new Everlast Power Pro 205. I went to Praxair and Weldco to compare prices.

Praxair would not sell me anything larger than a 40 cu.ft. cylinder and was more interested in leasing to me a larger cylinder. I already own one of these small cylinders for my Lincoln Invertec V100-S scratch start Tig machine.

Weldco wanted $375 for the 'M size' cylinder filled and $120 to refill it each time. I asked about the larger cylinders and they are not for sale but they will lease them at $75/yr plus $200 for the refills. I checked my receipt for the last 'M size' cylinder of Argon/CO2 that I purchase a few years ago for my Millermatic 210 Mig machine and it was $350 filled.

Argon is getting expensive in my neighborhood. If anyone knows of a more economical Argon source in my neighborhood, I'm all ears. At this point, I'm seriously considering the $75/yr lease option as I don't have to refill as often and the refills are less expensive. For the moment, I'll just use the small 40 cu.ft. cylinder until it is empty. They want $80 to refill the 40 cu.ft cylinder. Hardly seems fair...

BTW - Is it possible for me to refill my 40 cu.ft. cylinder from a larger leased cylinder? The Argon is not volatile but the pressures are pretty high. I'm thinking that a very small orifice between the lines of the two cylinders would allow it to fill the smaller cylinder at a controlled rate. Is this dangerous or am I on the right track?

In the meantime, I'm going to experiment some more with my new MultiPlaz welder/cutter that doesn't use any of the expensive stuff.

You said, "BTW - Is it possible for me to refill my 40 cu.ft. cylinder from a larger leased cylinder? The Argon is not volatile but the pressures are pretty high. I'm thinking that a very small orifice between the lines of the two cylinders would allow it to fill the smaller cylinder at a controlled rate. Is this dangerous or am I on the right track?"

Yes, it is. I sometimes do this with helium, since we actaully waste some where I work. You do not need a restricting orifice for non-flammable/non-oxidizing gasses. All you need are two bottle fittings, and a properly rated flex hose between them.

Steve

Steve, you had me confused at first, when you said 'Yes it is' as I initially thought that you were implying that it is too dangerous. The idea of the small orifice in the line is to slow down the transfer rate, so that there are no thermal effects as the gas changes cylinders.
i.e. Like when a fire extinguisher gets ice cold when you suddenly discharge it.

BTW - I got the idea of the orifice in the line, because that is how the differential cylinder pressure tester works for my aircraft engine. They use two gauges, one on either side of the orifice. The design is made that you supply a regulated 80psi to the line side and the acceptable leakage on the aircraft cylinder side should not exceed a certain percentage in psi. Ideally, 80 psi on both sides of the orifice is considered perfect. I often wondered why they settled on 80psi for this test and until you have tried to hold a propeller from turning at 80psi, you won't understand. It takes a considerable effort to hold the prop from flipping around and killing you. The trailing edge of the propeller is also very sharp, so you have to use leather gloves when handling it. The prop has to be held in position at Top Dead Center for each of the cylinders that you are testing.

I also have a USB Borescope/Endoscope for inspecting inside the cylinder via the spark plug hole.
This was a $25 purchase thru http://www.tomtop.com It works good and connects to my laptop.
Also, great for checking for dental cavities.
http://www.tomtop.com/usb-endoscope-wat ... pe-5m.html

I'll have to check on that borescope. I've been looking for one to inspect vacuum-jacket piping with. Thanks for the link!

There's no harm in using the restricting orifice, other than slowing the process somewhat. We transfer high-pressure He from full to empty bottles frequently (to purge freshly re-certified bottles back to He), and simply use the valve on the full bottle as a "throttle".

Steve

Hey, WerkSpace,

Thanks again for the link on the borescope. I forwarded it to my boss last night. To my surprise, the first thing he said this AM was that he'd ordered one.

This should be very usefull where I work.

Steve S.