Welding Cart Modification

Welding Cart Modification

by tommy b

This article describes how I modified a Harbor Freight welding cart (p/n 40544) to better fit a Millermatic 135 MIG welder.

Figure 1 shows the cart as bought.



What I don’t like about it is:

1) It is too tall. The welder sits so high, I thought the unit would be top heavy, especially since I like to do my welding outside in the yard when I can.
2) The cart is intended for a small gas bottle. The welder interfered with the 80 cf bottle I have.
3) The chains that are meant to hold the bottle in place are ineffective. They allow the bottle to wobble excessively.
4) The top tray, where the welder sits, has an upturned lip that prevents the access door on the side of the welder from opening.
5) The bolts that came with it were metric. I replaced them with ¼"-20 x ½" long bolts, with nuts and lock washers.

What I did like about it is:

It has a good, strong, welded bottom tray with rubber tired steel wheels and rubber casters.

Figure 2 shows the part of the original cart that I used.



I made the parts I needed from 18 gauge steel sheet. I made the handle from ¾" EMT conduit. I used ¼"-20 x 2" long bolts to hold the handle to the cart. Make sure that when you install the handle, it is far enough forward so the wire feed access door misses it when opening.

Figure 3 shows the fabricated parts



Figure 4 shows bending the sheet metal parts.



Figure 5 shows cutting the hole for the bottle in the top panel. I used a saber saw with a 24 tooth blade.



I also rolled a ring from 1" wide strap to hold the bottom of the bottle. Figure 6 shows rolling the ring.



Figure 7 shows welding the mounting tabs (1" angle) to the ring.



Figure 8 shows the ring bolted into the base of the cart.



To attach the welder to the cart, I drilled out the four holes in the feet of the welder to ¼". See Figure 9.



Two of the holes can be accessed by lifting the door that is used to install the wire spool on the machine. To reach the other two holes, the side /top panel must be removed. To do this, take out the six ¼" sheet metal screws and the two outermost 5/16" screws holding the handle on the top. See Figure 10.



To locate the hole positions in the top panel of the cart, remove the welder side panel, as above, and open the wire feed access door. Set the welder in the desired position on the cart and mark the hole locations on the cart top panel. Remove the welder and drill the holes in the cart top panel.

Figure 11 shows the holes with the bolts in them.



Figure 12 shows the completed assembly.



A couple of other notes:

I slit a piece of small plastic tubing and lined the bottle hole in the top panel to keep the bottle from rattling. Figure 13 shows this.



I also used the hanger brackets from the original cart, mounted on the front of the handle to hold my leads. See figure 12.

I believe this is a much sturdier arrangement than the original HF cart. If you have any questions, PM me and I’ll try to answer them. Happy jeeping.

tommy b

 

Very nice! Is the spot welder the one HF sells? If so, does it work well? I've been thinking about getting one with some of the sheet metal work I've got coming up. Anyway, nice work and thanks for sharing! Nickmil

 

Very nice.

 

You've got some neat tools. A man should have good tools.

 

I've been to his place a couple of times, and he does have some neat tools. A very well set-up shop. Now, he just needs to finish some of his car projects! R)
















j/k Tom!

 

No, it's not the HF model. It's a 220 volt model that I borrowed from a friend. It has an adjustable time setting on it so that you just hold the trigger down and it will stop the weld by itself, rather than having to estimate when your weld is proper and then let go of the trigger. I think you get more consistent welds this way. The HF model doesn't have this feature.

tommy b

 

Awesome job man! I'd love to have all thoes tools...they're in my "someday" box. Right now I'd settle for having a good bench vise . Looks like you should have just built the whole cart yourself...much better than HF any day!

 

I know where you're coming from. I'm almost 68 years old and I'm still accumulating tools. (although it's nice to thumb through a tool catalog and say," got that, got that, don't need that, got that... etc.) When I bought the cart I thought I was going to use the whole thing. When I found out it wouldn't work for me, I thought I'd just modify it and save the trouble of searching for wheels, casters and then make a base. Just lazy, I guess. But I have found that it's much easier to modify an existing design of someone else's than come up with a totally new design of my own. FWIW, HF just had their 5" Bench vise (#5655) on sale for $40, (regularly $57). For the price, I really like it. The head rotates in a vertical plane and it is beefy. I've got two of them. Not that I like them THAT much, but my shop and my garage are over 200 ft. apart so I either get two of everything or get my exercise walking back and forth to get the tool I need. And it seems that every time I need a tool, it's in the other location . On the vise, if you wait long enough, everything at HF goes on sale sooner or later.

tommy b

 

Although this is an old thread, I am interested in the mods that tommy b made to his HF cart. Any chance that anyone copied the pics and could repost them for our benefit? Thank you