Wednesday, October 10, 2012

The Eagle Has Landed

One of the major items I have needed for the shop is a good sturdy welding table. I have been getting by with the small forming table I built a while back but it has some problems as a welding table. Now that really high quality laser and oxy fuel cutting are relatively inexpensive I figured I would just built exactly what I wanted once and for all. I have been kicking several designs around since I had to draw up the forming table for Nowell steel. to cut for me anyway.

Here are some of the table configurations I looked at. The forming table is the layout in the lower left corner. Above that is what I almost had cut. It has a series of slots cut so that a Bessey clamp can be passed through for clamping out in the middle of the table. The slots are arranged so that there is full clamp coverage over the entire table. Good thing I had the little forming table cut first. Since it was all we had, it became the shop welding table while we waited to get the larger table. It turns out that those cutouts are a pain when you are doing small fabrication jobs. All your tools fall through the holes and frustrate you when what you want is a little flat area to work. After realizing the cutouts would frustrate me much more often than I needed them for clamping I redesigned the table. Eliminating all but one in the center of the table where it is difficult to get any serious clamp pressure normally made a good compromise.
 A neat video of Nowell cutting some thick plate with changing torch elevations. This shows you what is possible with plain old oxy fuel cutting. They don't make lasers yet that can do this kind of cutting, yet.

Table layout after removing all but one slot. This gives plenty of flat unholy area to work but leaves the door open for clamping out in the center. I thought I would use round pipe legs on this table with cheap steel pre-drilled flanges from McMaster so I wouldn't have to cut any thick plate. Material handling is my only problem with a sweet table like this. My truck wont handle it, its too heavy for my crane once its in the shop. What I really need BEFORE I order a cut plate is a forklift. Note to self. Keep eyes peeled for forklift at reasonable price.

My buddy at the scrap place hooked me up with a really nice chunk of steel plate for a welding table. It was thicker than I was planning on but the deal could not be ignored. The only problem was I had to move it. As is where is means just that. There was some timing issues that almost collapsed the deal partway through. And good thing the new Hyster is running. And just in the nick of time I might add. I really wasn't looking forward to moving the steel plate for the welding table by any ancient back breaking methods.

Phase one was to get the plate out of the hands of the scrapper. To calibrate the readers the plate alone weighs 2000 lbs. This is a wee bit of a logistics problem since all I have for a truck is a small easily crushed Toyota. I could rent a truck I suppose, so I checked into that. For a truck that can haul the plate and match up with my dock to make unloading easy was the better part of two hundred dollars for a one day minimum. If my forklift wasn't ready and I had to rent one it would be another three hundred bucks for the forklift rental and pickup/delivery. It was now looking grim if I couldn't get the planets to align. I hated to have to pass on the plate just because I couldn't move it in a timely fashion.

It struck me after looking at the plate. I thought to myself, "gee it sure has a thick mill scale on it. It would be great to wheelabrade, it or better yet Blanchard grind it flat." I wonder how much it would be to grind a plate that size to some easy grinding tolerances? The answer is, less than a truck and forklift rental including pickup and delivery. For a fab table this size I only need flat to .005 or .010. What is more important is nice and smooth. I asked for grind to clean, flat to .005 with a 32rms finish. 32 rms is a semi fine machine finish you might find on a lathe turned part with a smooth to the touch finish. Not too hard or expensive to produce by grinding and smooth enough that things slide easily on the table.

Jim at Advanced grinding worked his magic and a short time later I had a flat smooth table on the way.
Delivery day at the shop.This is almost cheating with the forklift. It took longer for the truck driver to unhook his straps than it took to unload the plate. Advanced wrapped it very nicely. It had paper and plastic stretch wrap covering the nice freshly ground surface. I have used other grinders over the years and your lucky if you get two by fours under the plate when it comes back.
With the forklift holding the plate I bolted the legs on. The harder part will be moving the plate inside. I don't want to run the forklift indoors until I get it converted to propane. The exhaust out of this thing is like the good old days before any smog control equipment. Just like being at the antique car races at Laguna Seca, the smell of victory.
Out come the machinery dollies for the move into the shop. These are homemade of course using plain ball bearings as wheels. Using a three point setup like the one above keeps an equal load on each dollie. Nothing like scooting along and having the load tip one way and have twenty five percent of your dollies roll out. The dock concrete has some artist swarf on it and I needed a little help from the croc footed neighbor to roll over some crunchies until I got it inside on the smooth warehouse surface.
You can steer the dollies with a short length of tubing. Its even easier when you have feet like this on the bottom that rotate with the dollie. The wood acts like friction material and keeps everything in place.
It isn't hard to push on the smooth concrete like the picture might lead you to think. I wanted to keep my eyes on the dollies to make sure nothing misbehaved. I would have preferred to use the pallet jack for the whole thing but I didn't have any spanners long enough to clamp between the legs in the long direction.
The one and a half inch thick forming table is looking kind of small now.
In position and ready for some work. Notice the foot pads. They are oversize from the legs so its easy to clamp a welding ground to them. You can also put bars across the pads so the table can be easily moved with a standard hydraulic pallet jack.

End.

5 comments:

  1. Hey Tom, I was wondering how you bolted the legs to the table. Also how did you cut the slot out of the center and I was wondering if it distorted the table in any way. Awesome job! Thanks.

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  2. Hi Ray,

    I never ended up cutting the slot in the table. After using the forming table a bit I changed my mind and just went for the smooth niceness of a solid surface. What you see above is how it sits now.

    All the best,

    Tom

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  3. Replies
    1. Hi George,

      About .31 cents a pound for the table and grinding. Less than bottled water and dogfood by the pound.

      Thanks for the comment.

      ---Tom

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