Welding Tips and Tricks

I started building a table back in October and I figured I would post a few pics and incorporate some lessons learned. I have been welding at the self taught, amateur level for a long time, but this is my first serious project. Feel free to let me know if you have any "tips or tricks" for me to use in the future. I am using a gantry from Precision Plasma and using his blueprints as well. The electronics are from CandCNC. Many of my modifications have been plagiarized from other builds found on the interweb, but some are actually my own. Feel free to make fun of all the crap in my garage.
I ordered and received most of my tubing and flats from McKnight Steel in Warminster, PA. I laid out the frame and built it upside down to make it easier to keep the top flat and square. This worked out well but I made one mistake here that should have been avoided. After tacking it up, the far right corner was out of plane by a smidge and I ground out the tacks to re fit. In the process I removed enough material that when I finished welding it up, the tube contracted and the long bars are out of parallel by 1/8" over 12'. This should not affect the performance, but it annoys me. Lesson learned; avoid distortion by good fit up and controlling heat.
I put the feet facing inside to increase the angular clearance between the feet and the casters for instance when rolling up or down a ramp. I also increased the distance between the top and bottom tubes to allow for material storage, and provide appropriate clearance for the 6.5" casters. 23.5" vertical tubes allowed for 4" total foot length. The casters are double locking from Service Caster; they are pricey but the double locking feature has come in handy.

If you take your time you can hand tap a 1/2" hole in 1/2" plate 15 degrees off, even when the hole was drilled perpendicular. Lesson learned; be careful when starting threads and make sure to use an appropriately tapered tap.
After painting the bottom I flipped it over (with the help of some friends and the wife) and started working on it right side up. Before installing the gantry rails I noticed that the middle vertical tube had expanded and caused a slight bow in the top tubes. I spent about an hour grinding the top tubes flat using an 8' straight edge. At this point i decided to get serious about learning to control distortion and that's how I found this forum. After a lot of grinding drilling and tapping I have the rails on parallel and level in both axes. Lesson learned (again); avoid distortion.
I had a 66" X 126" water pan bent up by Hoover Steel in Schwenksville, PA. It took a while to find a shop with the capability to bend that size, but it came out nice. I welded up the corners and primed it and the surface it will sit on. I built a computer/monitor stand based on the example form M FAB on the Precision Plasma site. I also installed racks for sheet material using 1" tube and 3" end posts. I just tacked in the end posts to avoid distortion.
I added a 2 x 3 rectangle tube frame around the water pan and drilled 1" holes in it for Hudson Bearing 5/8" drop in transfer bearings. I primed it with Sherwin Williams Pro Industrial Kem Bond, a direct to metal primer.
I built an enclosure for the CandCNC controller under the 0,0 corner with a sloped top to drain any splashing fluid, and some holes for cabling.
I added a shelf in the back for the Hypertherm Powermax 65. CandCNC recommend keeping the power supply and the controller separated by 5-10 feet, so the PM 65 is in back and the controller is in front. I then painted it up in Sherwin Williams Pro Industrial High Performance Epoxy. If this seems like a Sherwin Williams ad, it is. My brother works for them and got me a discount so I figured, I'd give them a plug. It is expensive stuff but I was able to get the whole thing primed and painted with one gallon of each.

I have some doors and panels to paint, but other than that it is just a matter of installing the gantry and controls. I'll try to continue this topic as I wrap it up.

Thanks in advance for any suggestions or advice

Mike

Very nice looking table.
Look forward to following your progress.

That's a serious table. Very involved fab project. I'm in to see your progress. I totally missed this thread when it was new....

that is really similar to a 4 X 10 I built as a layout and jigging table a couple of years ago but since I wanted to be able to sit at it like a desk to do drawings I only ran braces on 3 sides leaving the front open. I also let the top hang over the frame by about 3.5 inches to allow room for using clamps which has come in handy. like you I built upside down in an effort to keep the top as flat as possible. Ironically I just moved it out of the shop last week, it is still handy though, I layed out a set of stairs on it this morning.

good job !!

VERY NICE,, Mike, keep the updates coming.

Thanks all, for the words of encouragement. I have gotten a lot of benefit from forums like this along the way and I hope this topic might help someone else down the road.

I have fit up some doors and panels for the sides, installed the gantry, ran some of the cabling and connected the PC to start testing motion.

I disassembled the torch from the cable, ran the cable through the track, and put it all back together. Then I realized I needed to route the cable through the frame. So I drilled some holes and trimmed the cable rack rail. These 1" holes in 11 gauge would have been much easier to drill on a press vertically, rather than by hand horizontally. Then I took the torch apart AGAIN and re routed it properly. Lesson learned; A few extra minutes of planning can save time down the road. I guess if I made no mistakes in my planning, I wouldn't have anything to fix. Another lesson learned; when planing holes for routing cable, consider going up a 1/4". I used 1" holes and I wish I had gone with 1 1/4". I also used 1 1/2" tubing for the workstation and fitting all the USB, power and cat 5 through that was tricky as well. I wish I would have gone with 2" for the workstation, but I had the 1 1/2" on hand.

Very nice!!

Finished mostly, needs some touch up and a little tuning but seems to run really well.

Very Nice job.

That's Badass

Thanks! it was a great project, I hope I can make some money with it.