Mig Welder questions

You might contact a local metal fab place and see what they'd charge you to plasma the excess off. If you took care to mark the layout and only brought them what you needed cut, they could probably zip through that with a handheld plasm torch while you waited.

 

Good idea but I can't move the saw. I had to get a friend to transport it up from TN in his truck (now he lives 8 hrs away) and then pay a local nursery to use their fork lift to get it off the truck (weighs 700 lbs).

I think I'm going to have to suck it up and either grind for weeks or pay an ass load of cash for a plasma cutter unless there is another option not yet considered.

I think my pancake compressor is a little undersized for the plasma cutter use. It puts out roughly 3 scfm instead of 3.6 at 60 psi so its going to stop and start I think. Might be ok though since I don't think I'll be using a plasma cutter often.

I wonder if I could use it to cut ingots up or cut sprues off??

 

I'm sure you could if you bought a large enough unit. Also, if your compressor isn't up to the task (and it doesn't sound like it would be), you could pick up a large bottle of Oxygen and run the plasma cutter off that. That's how it's done in industry.

You might also think about buying or borrowing an oxy-acetylene or oxy-propane cutting rig. The cut wouldn't be as pretty as plasma but it would certainly be faster than a grinding wheel. And, they're definitely less expensive than a plasma torch. (But they don't cut stainless or aluminum.)

 

Just throwing this out there. re-make the lid out of angle iron (skeleton) and skin it with sheet metal.

Re-cycle the old lid as a grill

Oxy-acetylene would be the way to go to save $ and time to grind it up pretty.

 

I've got an oxy/acetylene setup already with a huge cutting tip. Never tried using it for cutting before though.

Well I ended up coughing up $436 shipped for this plasma cutter (Lotos 50 Amp Non-Touch Pilot Arc Inverter Plasma Cutter for Metal, Dual Voltage 110V/220V, 1/2 inch Clean Cut https://www.homedepot.com/p/Lotos-5...0V-220V-1-2-inch-Clean-Cut-LTP5000D/205448232). If my compressor isn't up for the job (which it probably won't be) home depot has several larger compressors for sale in stock in the store so I can just swing by and buy one. It looks like even the larger 1.7 hp compressor only puts out 5.1 scfm at 90 psi which will run this cutter but oddly not sand blasting continuously (needs 7 scfm).

Think I'll need to buy extra tips for the plasma cutter for this job or is that not going to be an issue? Never mind, I got 10 from ebay for cheap with a few spacers and other consumables.

It would be nice to have a mig as well. I have 2 large 20# tanks for CO2 that just need refilling and regulators up the ass, but I'd need a mixer valve and the mig machine to make it run which is minimum 900 bucks for both. Not sure if that's doable with the recent plasma cutter purchase. I might have to tig welding the hood out of necessity (good practice though!).

 

Send out the cutting work man..... I don't know what you are doing or even wtf that thing is... But if you can bring it to a local shop and tell them what you need, you will be floored by how cheap water jet or cnc plasma cutting actually is. Even more so when you provide the metal. I have a water jet shop in houston I use and they are 80bucks an hour. Best part, when I send them a job, the price is always 80bucks. Typical shop rate minimum. So that tells me it took them less than an hour to bang it out. Some times it's beneficial to save wear and tear on your own ass and just pay the man. 40ft of cutting in 3/8" steel is definitely the time to farm out the work. Your lungs, nose, eyes, ears and FINGERS will thank you from the countless HOURS of cutting you'll do with a box of cut off discs.

 

Well, scrap my idea. 400bucks is dirt cheap for a 50amp plasma torch. The chinese are the kings at the race to the bottom. If it cuts this stuff and doesn't burn up, You win! Hell, you can buy 4 of these cheapys for what a hypertherm costs. (I've always thought those guys are THIEVES, but what do I know) https://www.weldingsuppliesfromioc....MI2ePok4OT2AIVl7jACh3oVw_UEAYYASABEgITIPD_BwE

Hope you have a really good dryer... One thing I do know is plasma cutters like bone dry air. Glad to see you getting your shop together bro!

OMG... they get even cheaper! https://www.amazon.com/dp/B004VFJL1...t=&hvlocphy=9027553&hvtargid=pla-382451644259

 

Make sure you rig up a decent air-dryer inline with your new plasma rig. It has been my experience that humidity and moisture are the death of plasma cutters.

 

The cheaper version lacks the auto no strike arc feature that I got on my machine that's why it's cheaper.

I think it says it comes with an air drier in the description?

If not can I pick an air drier up from horrible freight or home depot or is it one of those items they don't sell in real life and needs to be special ordered?

Yes glad to get my shop tools together. I also bought a 4 jaw chuck for the southbend recently so I cam use the lathe now. Just need a few more tools and a rewire of the electricity to the shop and I will be set.

 

She aint coming with a dryer bud! Harbor freight has cheap inline air dryers. I have one of these. I set the regulator on it on MAX and never touch it as the threading is laughable... outside of that, it does it's job.

https://www.harborfreight.com/air-t...es/industrial-air-filter-regulator-68247.html

I See that the "P" stands for pilot arc. I saw someone said the air req's for this thing is 3.8cfm @66psi. That's not a lot of air. You may pull it off.

 

Just went to the sheet metal shop. I settled on 16 g sheet steel. The 20 g seemed to flex a bit too much for my liking. The 16g also gives me a bit more to work without melting through it. I think the 16 gauge will add about 20 lbs to the lid. In total I'm hoping the lid weighs under 60 lbs.

Also bought some other metal supplies and managed to arrange help drilling the holes for the bearings for the vice. The holes probably won't be super accurate so the bearings can be press fitted in but epoxy and a threaded holder plate should keep them in place.

 

More thinking about the 16 gauge and the lid. Back to the drawing board (aka back to you folks with questions).

My plan is to cut out the center of each facet on the roof so I have a skeleton frame, then weld some thin sheet steel over it to keep the oil spray inside and make it look pretty.

People on the rock forum said they *think* their big saws use 24-26 gauge steel for the roof. But this sounds extremely flimsy to me. I went to a sheet metal place today and felt some 22 gauge metal and it seems like it would be easy to dent and damage. Like I could bend it with just my fingers on one hand. Do you think 22 gauge metal will be too thin to make a decent lid cover?

I calculated out some final lid weights using different gauged metal:

These are the options:
16 gauge metal: 90 pound lid, which means I will have to push up with 45 pounds to lift the lid unaided.
22 gauge metal: 56 lbs total and 28 pounds of force needed to open it.
26 gauge metal: 45 lbs total and 22.5 lbs of force to open it.

Of course the thinner the gauge the more flimsy and more easily it will get dinged and damaged.

Where is the sweet spot?

 

I would go buy a stick or two of angle (size of your choice, I don't understand what this box is) and remake the lid frame. Save the 3/8 for another project. 16 vs 22 ga ... I'm not sure. I use 22ga to build windmill tail vanes and replacement sails (fins). Flat is can be a little flimsy, particularly a big sheet. But for the tails I roll it around 3/32" wire and it stiffens up considerably (also typically a couple of stiffeners). For sails, I put in the curve on slip rolls and it stiffens up considerably.

You will have the frame with the sheet presumably welded on the inside, 22ga should be pretty stiff. You may want a stiffener across the top if it seems a little bouncy. I think I would go with 22ga ... unless you are going to be dropping stuff on the top of this thing. I have some oddball 3'x5' sheets of 18 or 19ga galv and they are pretty stiff (once you bend in a corner or radius). 16ga just seems a bit excessive.

 

Zap, why can't you incorporate some counter ballast weights on the back of the lid to assist with the offset weight issue?

That, or a hydraulic arm?

 

The project is a 24" wet saw box for slabbing rocks I've got a much longer build thread over on RIPavenue.

I looked into counter weights and I'd need something like 1200 lbs with a 10 inch strut to counterbalance the 210 lb lid. That's expensive since only steel has the weight I'd need to hit 1200. I looked into gas shocks and calculated everything out but then I kept imagining the 210 lb lid guillotining me while I was inside and decided it's best to just make it lighter just incase the worst possible thing happened. 'Plan for the worst and the rest is a cake walk' or something.

I'd rather not remake the entire hood if possible since there are mud flaps along each internal wall and it fits into the base fairly precisely and has good heavy duty hinges that I have no idea where to buy.

Even if I completely redid it I'd still end up with the same exact choices that I have now since I'd still need to put an inner frame inside the sheet steel shell to stiffen it up.

So I hear 1 vote for 22 gauge. Anyone else for 22?

I'll go back tomorrow and double check the 22 again. Might be the way to go.

Or the 16g and add some low power gas springs? I already have the calculations done for where to place the springs to open the lid.

I really appreciate all the feedback. I'm definitely out of my comfort zone on this project and all your opinions and help has been invaluable. Learning a lot on this one.

 

Ok new plan. One of the rock forum guys convinced me.

So I'm going to cut the entire lid off my saw leaving only the very base of the hood which has the hinges and mud flaps (the only real important stuff). This rectangular piece will have a new 22 gauge hood welded onto the top of it. The hood will have a curve running from front to back. This will ensure the lid has some rigidity to it but will significantly cut the weight down to around 48 lbs total which means 24 lbs to open it. Very doable with 1 hand and not a death trap.

Pics and updates soon.

 

Why screw with at all??????? Autozone gas lift struts..... You'd be amazed at what those things can lift! In 1969, Jaguar actually used ONE little 12" gas strut for the entire bonnet! They didn't become standard on cars here in the states until the 1980's. A pair on that lid and you can move it with 2 fingers. https://www.walmart.com/ip/BOXI-2pc...7271&wl11=online&wl12=228268038&wl13=&veh=sem

Why I didnt think of this one before is beyond me. John clued me in when he said counter weights. I might actually get a "like" for that stellar idea!