Welding cart/torch stand for my oxy-propane rig

[JHCC]

As documented elsewhere, I recently made the decision to add an oxy-propane torch to my little shop. This naturally creates a need for some way to store the rig and move it around the shop. I had the idea to combine a cart for the tanks with a torch stand such as the ones described HERE and HERE, and this is how far I've gotten.

The base is a dolly I picked up at the industrial surplus place. There's a large ring upon which I can put a 20 lb or 30 lb propane tank. The central post is attached to two rings that can hold one or two tanks up to 125 lbs each, although I am planning to start with a single 80 lb. 

The tall post has a gas saver on top, screwed down to a plate on top.

I haven't yet decided what to do with for the treadle, but I've got some ideas floating around my head waiting to coalesce. Two things that I am going to do are to shorten the tall post and add some kind of locking foot mechanism to keep it from rolling around while in use. Regarding the former, I overestimated the proper length needed to put the torch at a good working height. As for the latter, I'm thinking that something outside the lines of the base will give me greater stability than a single point in the middle. The tall post will also have a hook in the front for hanging the coiled hose and probably a short strut to connect it to the top pair of rings for additional strength.

More to come....

 

 

[Frosty]

It's looking pretty good John. Have you figured out a way to lock it in place? I was thinking of a flip down fork thingy the wheels couldn't roll over but I couldn't make the images in my head work. 

The torch hangs pointing the other direction, towards the pilot light. That way if the torch is lifted it gets lit so you don't get a flammable stream of unburned oxy propane shooting into your shop. 

Frosty The Lucky.

[Irondragon Forge ClayWorks]

The only suggestion I have is to hinge the top oxygen tank rings to make it easier to get the tanks out.  Even an 80 pound tank would be hard to lift it high enough to clear the ring.

[JHCC]

21 minutes ago, Frosty said:

The torch hangs pointing the other direction, towards the pilot light.

Yeah, that was just hung up quickly for photo purposes. I'll be making a hook to clamp onto the rosebud's shaft, and I think I should be able to experiment with the best mounting position.

As for the feet, I'm thinking of a pair of eccentric cams on an axle with a foot pedal. When the pedal is depressed, the cams (which are outside the frame of the base) lift the front end of the base enough that the casters lift off the ground. The cams can be flat on their bottom sides to keep them firmly in place until they're rotated back out of the way again. 

6 minutes ago, Irondragon ForgeClay Works said:

Even an 80 pound tank would be hard to lift it high enough to clear the ring.

The top of the ring is 31" above the floor. If that turns out to be too high to lift over, I'll definitely consider hinging them.

[JHCC]

On 5/9/2021 at 10:14 PM, Frosty said:

The torch hangs pointing the other direction, towards the pilot light. That way if the torch is lifted it gets lit so you don't get a flammable stream of unburned oxy propane shooting into your shop. 

Frosty, I've been looking at a number of YouTube videos of gas savers in use (Yeah, I know; don't start with me -- I'm talking about folks like John Switzer of Black Bear Forge), and it looks like the only ones that auto-light are torch stands for working hands-free. Otherwise, folks seem to pick up the torch handle, light it by putting the nozzle tip at the pilot light (or with an electric sparker), and move on. 

[Frosty]

John: You are one of the people I don't worry about following dumb ideas on Youtube, you've been around the block a few times. You ask if you're unsure. 

All I I meant to say, is with the tip of the torch aimed towards the pilot, the torch lights as soon as it's lifted and the valve opens. I admit I haven't used a gas saver in I'm thinking 50+ years but every one I used in the day hung the torch with the tip aimed towards the pilot flame.

My torch has a thumb valve and I rigged a sparker from an old trickle charger rather than buy a "real $" igniter.  I don't much like my Micky mouse sparker so use my piezoelectric sparker. 

I'm not criticizing but if I'm coming across that way I'll just watch and read.

Frosty The Lucky.

 

[JHCC]

Going back to my early sketch for the cart, putting the pilot light between the gas saver hook and the work area means that I'll be moving the torch past the pilot light anyway:

Nice, natural ergonomics.

Now, for use as a torch stand, there are still a couple of ignition options. In the links in the top post, one torch stand is simply a gas saver with a pedal to open the valve (presumably requiring manual ignition), and the other has the tip of the torch next to a pilot light for automatic ignition. There's another version I've seen in a YT video that's basically the same as the first, but the user has the gas saver's fuel valve adjusted to allow through just enough acetylene to keep a tiny pilot flame going at the tip of the torch. I don't particularly care for this option (basically because I want "off" to be OFF), so I will probably have a separate mounting bracket on the post to keep the tip of the torch next to the pilot light.

[JHCC]

Shortened the front post and added a wheel lock:

The latter is made from a length of pipe, another of rebar, and some bits of angle iron. It’s flipped up to move the cart around:

When flipped down, it lifts the front casters about 1/4” off the floor:

The casters at the other end are fixed, so they can’t move side to side. 

As you can see, this adds about 7” to the width of the front end, increasing the stability while in use:

Next step: treadle for the gas saver arm. 

[JHCC]

It occurs to me that the best term for this mechanism would be “kickstand”, since it doesn’t actually lock the wheels. 

[JHCC]

Still need to make a bracket to hold the torch on the post, but otherwise done. 

Gas saver pedal:

I need to contact the fellow who has the ferrule crimper so that I can make the short section of hose between the cylinders and the gas saver. 

[Frosty]

You aren't going to hang the torch from the valve arm as designed?

Frosty The Lucky.

[JHCC]

I will, but first I need to make a hook to keep it from slipping off. 

[Frosty]

But haven't you disabled the valve arm action with the foot pedal mechanism?

Frosty The Lucky.

[JHCC]

No, the gas saver works as normal. The pedal mechanism just lifts the arm when the pedal is stepped on; it doesn’t pull it down. 

I’m playing with ideas for something that will keep the arm pulled down while the cart is in torch stand mode. 

[Frosty]

That makes sense. 

Frosty The Lucky.

[Irondragon Forge ClayWorks]

I like your solution for the small oxy tank.

[JHCC]

2 hours ago, JHCC said:

I will, but first I need to make a hook to keep it from slipping off. 

Based on one I saw in YouTube video, here’s a quick test version in thin sheet steel:

I’m not sure if the weight of the torch pushing down is enough to overcome the resistance of the weight of the pedal pushing up. I may need to add a counterweight to the pedal to balance it better. 

[Frosty]

I can see the benefit of the pedal if you're going to have the torch clamped in another location, I used to put one in the vise at times, I identify. Maybe a weight on a hook to take the place of the torch for remote use? A storage ring could be attached under one of the gas saver mounting screws to keep it handy. 

As I remember them, the ends of the valve arm had a more pronounced hook, almost like a gate hook. Closer in shape to the sheet metal mock up you show. 

Frosty The Lucky.

[JHCC]

7 hours ago, Frosty said:

Maybe a weight on a hook to take the place of the torch for remote use? A storage ring could be attached under one of the gas saver mounting screws to keep it handy. 

I have a clever idea for this that I want to try; more to come later. 

7 hours ago, Frosty said:

As I remember them, the ends of the valve arm had a more pronounced hook, almost like a gate hook. 

I’m considering reshaping the arm (cold; no forging chrome for me!) into something with that kind of shape. Even a deeper V would be an improvement. 

[Frosty]

You shouldn't need heat to bend the arm. a V should be a real improvement. 

Frosty The Lucky.

[Glenn]

Use a vise to hold things while you bend them, slowly into the configuration you want.

[JHCC]

Small setback. I went to visit the fellow with the ferrule crimper, and we discovered — just after cutting off the short section — that the ferrules and stems were the wrong size. It seems that the information I got about size of the hose was incorrect: the actual i.d. is 3/16”, not 1/4”. Fortunately, he had a couple of the proper size stems, so I’ll be to use the long hose while waiting for the proper stems and ferrules. 

[JHCC]

Made the bracket to hold the torch. 

The nut holding the (heating or cutting) attachment rests on the upper fork, and the  two gas inlets twist to lock into the lower bracket. 

Positioning the nozzle above and slightly off-center to the pilot light:

[Frosty]

I've never seen a set up like that.

Frosty The Lucky.

[JHCC]

Just to clarify: the bracket on the side is not a replacement for hanging the torch on the valve arm as usual, but is for an additional, separate function.

Function One: Static workpiece, mobile torch. When I'm moving the torch back and forth between the stand and the work, the torch will hang on the valve arm as usual. I still want to tweak the hook or make a more robust version of the sheet metal hook, but I'll still be using the gas saver as designed.

Function Two: Static torch, mobile workpiece. When I'm using the stand as a hands-free, foot-operated torch stand -- that is, moving the work between the torch and the anvil -- the torch will rest in the brackets on the side of the post. For example, when I'm making sheet metal bowls, I can hold the blank with the tongs, heat at the torch, move to the dishing form, hammer until too cold to work, move back to the stand, and repeat, all without having to juggle tooling, put anything down, or pick it back up again. (This kind of torch setup was discussed in this thread back in 2016.)

The brackets on the post are NOT to hold the hold the torch during Function One, but to enable an easy, tool-free changeover from Function One to Function Two and back.