Lightweight log dolly, welded with 120volt MIG

   / Lightweight log dolly, welded with 120volt MIG #1  

Sodo

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Cascade Mtns of WA state
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Kubota B-series & Mini Excavator
I'm showing this as an example of a simple project that can be done well within the capacity of a 120v MIG. The welder was a Miller 135, which is rated to weld steel up to 3/16" thickness. You will see that some 3/8" steel was also welded on this project (with the 120v machine). This project was done 4 years ago and nothing broke, even though it was hastily constructed.

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I had to remove a bunch of small 6" or less trees that were obstructing the view. And for forest-fire safety, called "fuels reduction". The trees were tall and skinny, and bunched close together, on a steep hillside. My plan was to drag them up the hill with a 4WD ATV, and away to a pile. Very quickly, I found that the ATV could only pull one log at a time up the steep hill dragging on the ground. To speed up this job (pull multiple trees) they needed to be on wheels.

Off to the shop to build a lightweight dolly. It's made of 1 1/2" square thinwall steel tube. Dimension is .065 wall (also known as 16ga), or 1/16th inch, this is thin, and is on the edge of too thin, it takes a bif of technique to not burn holes with the 120v machine. To weld this with stick (and 3/32" rod) would require a fairly high level of skill, but a MIG can do .065 nicely with a lower level of skill. I was concerned that the thin-wall material was too lightweight for the job, but carrying it up and down the steep hillside, lightweight increase the amount of work that the people can do. Luckily it survived without ever breaking.

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The clevis hitch is 3/8" steel, welded with the 120v machine. While the 3/8" is clearly beyond the welder's capacity, I had no trouble with it due to the bracing plates on the side. I could have preheated it before welding but chose to brace it which was much faster and more efficient than the preheat process. By a later change of design (using the tongs) this 3/8" clevis is no longer used and could be cut off.

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Here's a 1/4" bolt for scale.

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One weld I thought might be at its limit was the one between the "V". I kept thinking I should have braced it with a vertical on each side (in compression, down to the frame), but had no problem. I actually left it un-braced, kind of like a "fuse" to tell me the strength necessary. But this thing was so far overloaded, so many times constructed as shown that I stopped worrying.

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There was one iteration on this project. We had hired help for this job, and to keep everyone productive I had to reduce the deadhead time. I found that I wanted to haul the dolly back to the hillside with the Log arch (the blue device), so I cut the frame corners at 45 degrees, and added a way that the log arch "tongs" could attach quickly to the log dolly for the return (empty) trip.

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   / Lightweight log dolly, welded with 120volt MIG
  • Thread Starter
#2  
I'm no expert, I just get a lot of use of my 120v MIG, and have used them for 20 years. I will just post some pics I've done with my Miller 135 and try to explain the projects, in hopes that folks are inspired to start projects and post them too. I also have a Miller Multi-Matic 200 which can weld at 220v, but currently have no (valid) 220v supply.

I have no experience whatsoever with a department store MIG - my experience with them is zero. I tried flux core wire once with a quality unit (Hobart 140), briefly, did not attempt to refine the technique, so that's all I know about flux core. I use 75/25 Argon/CO2 mix gas.

One strange thing I find curious is the number of members who will post to say that a 120v MIG is useless. They are adamant about it, but most of them will admit that they don't have a 120v MIG, never used one, or their only experience was a failed experience. They often have a 220v MIG or a stick welder and zero interest in a 120v MIG. Yet are fully willing to offer up "advice" and "experience".

Its strange, but it takes all kinds doesn't it? Anyway here's hoping they will refrain from posting their null-wisdom and leave this thread for those who have 120v MIGs.
 
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   / Lightweight log dolly, welded with 120volt MIG #3  
Yeah, there's a lot of negative opinion voiced here about the usefulness of 120V wire feed welders and thick material. I'm no expert. I just bought a Hobart 140 wire feed -- my Father's Day gift to myself and having fun getting up close and personal with that little box.

I don't see any problem welding 1/4" steel with flux wire in that 140. Use multiple passes. It's all in the preparation anyway (grind off the mill scale, bevel the edges properly, get the gap set up properly between the pieces). This is true whether it's flux core, MIG, stick, TIG. You just have to take the time to prep the job and then learn how to lay down multiple passes properly.
 
   / Lightweight log dolly, welded with 120volt MIG #4  
Nice job on the cart. If the tongue adapter (piece of stock between the hitch and the main frame) wants to kink on you, I weld caps on both ends of light gauge material like that which does a great job of preventing that. On your "V" I think your strength is in the fact that by using square tubing, you have the vertical members sitting in line with each other and in tension. With 30k or so tensile strength in mild steel, it works, as you found out.
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On the negative comments about low power MIGS, probably like a lot of things. We usually like what we have/have perfected and what's ours, and don't mind telling others (indirectly) why we did what we did. I had a little 120v 75 Farmhand from TSC that used flux wire; no accommodations for gas. Since I was going to be welding thicker material I figured the .035 diameter would be the wire of choice.

After I upgraded to the HF 151 with gas and solid wire, I still didn't get the results I wanted again with .035 but solid, while still in the learning stage. I changed to .030 and my welds improved significantly.

So, in retrospect, I probably should go back to the Farmhand with .030 flux wire and see how that works. May work just fine for me when I don't want to get the 151 out.

Mark
 
   / Lightweight log dolly, welded with 120volt MIG
  • Thread Starter
#5  
Nice job on the cart. If the tongue adapter (piece of stock between the hitch and the main frame) wants to kink on you, I weld caps on both ends of light gauge material like that which does a great job of preventing that.

That open 'piece of stock" between hitch and main frame was added to quickly use the log arch' "tongs" to grip the dolly (to speed transport back & load more logs). I understand what you mean about bracing against "parallelogram-ing" but there's no force on an empty dolly. Also with that new method the tongue is no longer used. It could be cut off but haven't been inspired to do so.

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   / Lightweight log dolly, welded with 120volt MIG #6  
Sodo
I see from some of your posts that you are experienced with 120v mig welding. I have never welded (I have burnt up metal a few times with a stick welder and muddled through a repair or 2) but I have a couple small projects that I need to accomplish. The skids/runners on my grader blade are wearing out and replacing them is getting expensive. The skids are about 1/4 in thick by 2 in wide and about 6 ft long. I want to use pieces of the old skids to weld onto wearing portions of the new skids to slow down the erosion so it doesn't get to the metal on the unit itself (this is not a project that could kill people on the highway if it fails). I bought a Hobart 140 120v wire feed and would like to accomplish this. I did not want to put 2000 dollars into a bigger unit. Thought I could start on this unit and if I ever feel qualified for larger projects I could step up my game with a bigger welder. I see a lot of TBN chatter that a 120v machine is not worth having. You have success with yours. Will this unit do this project for me? Can you give me any tips (grinding a bevel down the edges etc.) or direct me to any instructional videos or PDF's. It seems that 1/4 in is at the larger end of its capabilities.
My other projects so far are just adding metal to rotary cutter decks that have gotten holes in them.
Thanks
 
   / Lightweight log dolly, welded with 120volt MIG
  • Thread Starter
#7  
1/4 x 2" x 72" long sounds like a "heavy project" for 120v. Thats about the full extent of my ability to help, which I'm sorry if it looks like a standard internet "you can't do that" answer but may be able to offer more if a pic of the project can be posted.

I'm more comfortable considering 3/16" as a larger 120v project, with smaller 1/4 brackets here and there, like a couple inches of welding at 1/4". As I mentioned before, my Kubota LA 402 FEL and bucket is almost all 3/16 with 1/4" brackets, which would be a HUGE project for a beginner. The cutting edge is 5" long and might be similar to your "project" though, and would take some thought. Six-foot long & 1/4" sounds almost tailor-made for testing the hairy edge of 120v feasibility.

Or tailor-made for testing the hairy edge of your internet advisors. ;)

Can you somehow flip the grader blade over, (or unbolt it) and simply 'run beads' to build up the wear-edge? That may solve your immediate problem for a couple years while you build experience on the Hobart.
 
   / Lightweight log dolly, welded with 120volt MIG #8  
I have a Clarke 130 mig...I use flux core since I don't want to have to buy a gas tank and fool with that ...So far I've fixed my son's rake, a project for my granddaughter and my Bush hog and all the welds seem strong...Not Pretty...I'm just starting but they are strong and have held up...It works for me...:thumbsup: I paid $100 for it and it's like new...I think a welder would have charged me more than $100 to repair my Bush Hog alone...?
 
   / Lightweight log dolly, welded with 120volt MIG #9  
I was planning on tacking a couple inches at a time every foot or so along the edge. Don't plan on running a bead down the whole edge. It just has to hold it together as it wears down. Is that too much? Maybe I am not describing what I am trying to do well. I want to turn the grader blade upside down take hunks of the old skid and tack it on the bottom of the newer skid where it is thin.
Sorry, I don't seem to be able to attach a parts blowup of my grader scraper to show you what I mean. I can pick out the file to attach but it wont upload. Maybe I can figure it out later. Thanks for your help.
 
   / Lightweight log dolly, welded with 120volt MIG #10  
two 230amp 220 V AC welders , one 80 amp 120v mig , A/O unit with cutting tips up to 3" ....

AC for anything heavier than 1/8" , mig for lighter stuff / tacking ... A/O for hot wrench and cutting

all have their places / duties and work well when used appropriately.... dabbling in the spark arc since 1976 and still learning....

BTW ... neat project :thumbsup:
 
 
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