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View Full Version : Woodworking project gone part metal...



Brendan Plavis
05-24-2010, 8:14 PM
Okay, as some of you may have read a previous thread of mine, I am looking to build a work bench. But since I want it to stand up to the grueling punishments that I may subject it to, I have come to the conclusion that metal, with a wooden swap top and shelf, would be the best bet. Because, I am kind of a messy worker, and like surfaces that I can easily wipe up(I would use a sheet metal swap top for finish work.)

But my problem is, that I unfortunately dont have a welding torch to do the job. I thought about bolts, but, it wouldnt work for the way I am thinking of designing it... not to mention I would end up cutting them out, and thus collapsing the thing by the end of the second day... since I always manage to run into those kinds of things...

So, although, this is a wood working comunity, I was hoping a few of you would have welding experience, and could point me in the correct direction...

So my question is: Should I rent a welder, which would probably cost me about $45 per day, less the materials(shielding gas/flux wire, et cetera), or should I buy a cheapo Harbour freight one, for perhaps $109(can only do flux)-$180(can do gas+flux). I figure the project will take a few days, at the very least, and, the harbor freight ones come with a shield(I would get another one, since its only a hand held one... I would have singed retinas by the end of the day....) a brush, wire, et cetera.

I am starting up my job again, and just for this weekend, I rekkon that I will profit atleast $75, possibly more(not sure how long boss will keep me on, because it really isnt 100% beach season yet...) So, I am not too concerned about it costing a little money... but still, I want cheap....

So to break it down:

Rent(using online statistic): $45 per day
Buy HF: $109-$180 to own

Now bear in mind, I am not the one day gets all done kind of guy... I usually like to take my time... since rush=injury....

-Thanks
Brendan

Joe Wiliams
05-24-2010, 8:26 PM
Have you looked at Craigslist for used benches? They come up frequently in my area at least.

Bill LaPointe
05-24-2010, 8:38 PM
If you don't have welding experience you will probably not do a very good job. The solid core door that was recommended in your previous post is still your best bet.

Brendan Plavis
05-24-2010, 8:43 PM
If you don't have welding experience you will probably not do a very good job. The solid core door that was recommended in your previous post is still your best bet.

I am a quick learner(when I was one or so I walked into a door.... I learned quick not to do that again...) and MIG/Flux is considered the easiest to do, considering that it is point and shoot... unlike TIG or Stick where you have to hold a seperate rod....

Solid Door Core works for a swap top... but unfortuntely they arent metal... so they are still difficult to clean...

John Coloccia
05-24-2010, 8:56 PM
Maybe if you explained a bit what exactly you had in mind it might be easier. The odds of you properly welding something the first time out, with no experience or instruction, are pretty low. With Mig especially, you can make a beautiful looking weld that has the structural integrity of dry leaves.

Welding would be my absolute last choice for a piece of steel I'm hoping to keep dead flat, by the way. It's difficult to describe just how much steal will move when you weld it. There's quite an art form to straightening out a chromoly airplane fuselage after you've completed all your welds.

Brendan Plavis
05-24-2010, 9:08 PM
Attached is a rough drawing of what is intended. Sorry, its a quick draw up, not at all detailed. Not shown is that a piece of sheet metal would cover probably pieces from a bed frame(if I can find one *crosses fingers*) The symbol that occurs alot, thats a circle with 2 lines through it, for those not firmiliar, is a welded seam. Faint lines are there, but since I drew them afterwards, it made them faint...grr..

Charlie Gummer
05-24-2010, 9:19 PM
With Mig especially, you can make a beautiful looking weld that has the structural integrity of dry leaves.

Welding would be my absolute last choice for a piece of steel I'm hoping to keep dead flat, by the way.

John hit the nail on the head...twice.

I design large-scale marine deck equipment; most of the time I'm designing in structural steel weldments. We have some of the best fabricators around in our shop with decades of combined experience. The one constant response you get from a fabricator, in my experience, is not whether the metal will move or not (once heated) but how MUCH it will move. It doesn't matter if it's 1/4" plate or 5" thick forgings; heat + metal = movement. Thinner material moves around A LOT. The key to mitigating this movement is to very securely brace the structure and then stress relieve the weldment with the bracing in place.

Now I understand the scale of what you're talking about doing is significantly smaller; you'll still have the same issues (only on a smaller scale).

In my opinion your best option is to design around using fasteners (screws, bolts, rivets, whatever). Design based around commonly available materials and fasteners (McMaster Carr is your friend being in a remote-ish area). Not only will this be a more easily assembled bench but you leave yourself the flexibility to change the design in the future. You're already talking about having multiple tops that you can swap around; IMHO you're doing yourself a disservice by trying to weld the structure.

As always: YMMV.

Brendan Plavis
05-24-2010, 9:42 PM
John hit the nail on the head...twice.

I design large-scale marine deck equipment; most of the time I'm designing in structural steel weldments. We have some of the best fabricators around in our shop with decades of combined experience. The one constant response you get from a fabricator, in my experience, is not whether the metal will move or not (once heated) but how MUCH it will move. It doesn't matter if it's 1/4" plate or 5" thick forgings; heat + metal = movement. Thinner material moves around A LOT. The key to mitigating this movement is to very securely brace the structure and then stress relieve the weldment with the bracing in place.

Now I understand the scale of what you're talking about doing is significantly smaller; you'll still have the same issues (only on a smaller scale).

In my opinion your best option is to design around using fasteners (screws, bolts, rivets, whatever). Design based around commonly available materials and fasteners (McMaster Carr is your friend being in a remote-ish area). Not only will this be a more easily assembled bench but you leave yourself the flexibility to change the design in the future. You're already talking about having multiple tops that you can swap around; IMHO you're doing yourself a disservice by trying to weld the structure.

As always: YMMV.

For the way that I am designing it, I dont think fasteners will work, IMHO. I tend to over engineer things, in a way, that if I tried to fasten it, there would be more screws sticking out than modern art...

So, that is why I am going to weld it... I understand movement, and plan 100% to brace it where needed.

So, back to the original question: Rent or buy?

Paul Atkins
05-24-2010, 10:20 PM
Your brain is getting in the way of success. You ask for information and then throw it away. You want a table to work on, not a table to 'work' on. I have a 10 dollar solid core cherry veneer door workbench that I can throw up a piece of salvaged lab bench top for brazing /welding or I can throw up a piece of 1/8" steel for some other project. Once and a great while it might be cleaned off and there is a nice flat wood bench. 4 x 4 legs and I could put my Model A on it. It needs drawers, but that's another story. Someday there might be a real workbench in here, but there is too much 'work' to do for now.

Jeff Monson
05-24-2010, 10:35 PM
rent or buy, definately rent, I weld very quite often with a miller wire feed, I cant imagine trying to do a good job with a cheapo wire feed. You'll definately want to get some scraps and practice, 1st making some beads and then attaching 2 pieces together. I'd suggest breaking the 2 pieces apart so you can get an idea of the penetration it takes to properly weld steel. Its alot of fun to learn to weld...just make sure to learn proper feed rate and heat setting to obtain maximum penetration. As stated earlier, you can make a great looking weld and have no strength. Good luck.

Joe Wiliams
05-24-2010, 11:27 PM
So to break it down:

Rent(using online statistic): $45 per day
Buy HF: $109-$180 to own

Now bear in mind, I am not the one day gets all done kind of guy... I usually like to take my time... since rush=injury....



So, back to the original question: Rent or buy?
If you think it will take more than 2-3 days then buy.

Stephen Cherry
05-24-2010, 11:55 PM
I don't know if this is what you want to hear, and I respect that because people do many interesting things and learn about many things because they do not listen.

That said, in my tool kit, I have a tig welder and a mig welder, but when I updated my workbench recently, I used a maple top that I had, and made a base out of mortised and tenoned 4 x 4s, with 2x8 stretchers. It's strong, and stiff. My project cost was less than 40 dollars.


As for renting or buying- The answer is to definitely buy. Hobart, Miller, Lincoln, etc. are all good. Also, I would recomend a trip to the library of bookstore to read up a little about welding.

Leigh Betsch
05-25-2010, 12:04 AM
So, that is why I am going to weld it... I understand movement, and plan 100% to brace it where needed.

I wish you well but I'm afraid that your statement tells me that you don't really understand how metal warps when its welded. You can't just brace it to avoid movement you've got to clamp it, tack weld it in the right places, weld partial beads, move weld in another area to hold the first one from warping, then return the the first bead to finish it. When a weld pulls a member out of place, and it will, you've got to know where to put the heat to pull it back. Unless you know what you are doing I will guarantee the table will rock. Good clamps alone will cost more that the welder rental. Stick to wood, you can plane and sand it to shape if you need to. But if you do weld it my advise would be to rent a unit if you can, tack weld the heck out of it before you ever lay a full bead and watch for warp.
Like I said I wish you well but I would advise wood before welding unless you've go someone to help you that knows how to build welded things.

Dave MacArthur
05-25-2010, 12:49 AM
Deleted. Decided it's just not worth it.
put on Ignore List.