First Project - Work Tables

[USFASME]

Hi All,

We are a student organization, the American Society of Mechanical Engineers, at the University of South Florida. We will be receiving a Miller 140 MIG this week. Our first projects will be to construct two work tables, one a large conference like welding/general use table, and the other a cutting and tool station.

The plans can be found attached. The conference table PDF is too large, so one is PDF, and both are in the .zip file.

Our general questions are, what is everyones overall thoughts on the designs? Also, the top is 3/8" thick, and the legs are 1/8" wall 2x2 square tubing. What are good settings for the welder to weld this differential thickness joint? Shield gas will be 75/25, and I think the wire is .035".

According to our analysis, the projects can support significant loading, limitations are included in the drawings.

This will be our first welding project, so any advice is greatly appreciated. We have not started this project yet, so there is still time to make design changes.

Thank you,
ASME @ USF

[Chibrew]

I'll let some more senior members chime in, but I like the overall plans. You might want to look at the Miller workstation table for some ideas. A few others here have used concepts in it in there tables. They have a nice x pattern cut out in the worktop which makes it easy to clamp materials to the worktop. Good luck. There are a lot of smart guys here who can provide some good guidance.

Cheers,
Chibrew

[USFASME]

Thanks for such a quick response. The larger general use/welding table has an X pattern cut into it. For some reason the forum says the PDF is too large to upload on its own, so that one is included in the .zip file.

Thanks again, looking forward to hearing from others.

[email protected]

[MMW]

Build & weld the table frames first, then when that is done place the tops on & stitch weld them only. Maybe 1" of weld every 12". If you weld it to much the top plate will pull downward on the perimeter.

[MMW]

When ordering the top plates specify that you want it flat & don't be afraid to reject them if they come in warped. I would also make the tops 1/2" thick. What is the 1" flat bar that runs around the tubes for? If it is for hanging grinders & stuff I would drop it down 2" more so the opening is bigger.

[USFASME]

Great, we never would have thought of that.

Does anyone have the template, or specs, for the X cuts? I think are slot is a bit too narrow, and I think there is a larger hole at the end of the X to get the clamps in?

Thanks for such quick replies.

[email protected]

[MMW]

On the conference table the swivel caster can't rotate all the way around as it will hit the jack bolt. Once it is done don't be afraid to put holes in as you need them in the future.

[USFASME]

When ordering the top plates specify that you want it flat & don't be afraid to reject them if they come in warped. I would also make the tops 1/2" thick. What is the 1" flat bar that runs around the tubes for? If it is for hanging grinders & stuff I would drop it down 2" more so the opening is bigger.

It absolutely is for hanging things - thanks for the insider info, I already adjusted the models.

Also, wouldn't have thought plate so thick could come warped....we'll definitely check that out.

We'd LOVE to make it 1/2, and we're trying to get the supplier to give us a break as we're a student group, but 1/2 is a lot more expensive than 3/8.

Anyone know any suppliers in the Tampa Bay area willing to work with a student group? We race in a national electric car competition - great advertising potential.

[USFASME]

On the conference table the swivel caster can't rotate all the way around as it will hit the jack bolt. Once it is done don't be afraid to put holes in as you need them in the future.

Good point. I was just thinking you needed enough for left/right, but if you change direction it has to switch. I guess I can make those bottom plates larger on that side and move them over some.

[USFASME]

Does anyone have any idea on the settings? I see that the welder allows you to select metal thickness, but as one side is 1/8 and the other is 3/8 (or 1/2 if we could afford it...) which do I select? Also, is that a weld you would put a 45 degree bevel in for better penetration, or just butt them up against each other?

[email protected]

[cncmachinist]

wow always good to start with a plan but full autocad drawing got to hand it to ya pretty good design could be tweaked a bit but rock solid design


you could 45 the corners for weld penetration but if in the future you want to remove the plate or change the design (trust me i did after a year and i welded all the way around) stitch welds are more than enough but you might want to add a cross brace under the sheets around the x cut in the table you might get sag in the sheet if you make your table big enough ( both tables i made did this but the were much bigger with 1/2 plate and had to flat the second one collapsed under my granite surface plate )

[USFASME]

wow always good to start with a plan but full autocad drawing got to hand it to ya pretty good design could be tweaked a bit but rock solid design

Haha, we're engineering students, I can show you a file full of analysis on different loading configurations as well...

Being as this is the first time we've done this we wanted to get it right.

I think we will just leave everything butted up against each other, and definitely use the stitch method for the top. I'll look into the X pattern, but I believe the deflection with a 1000 lb point load dead center the deflection was something like 0.0073 inches. I'm sure we could run some angle bracket under it to sure it up though.

We're on a really shoe-string budget here, but everyone keeps saying go for the 1/2". We might have to save up.

[email protected]

[cncmachinist]

same when i built my set of benches the one under my surface plate was designed in pro/e for testing the weight too bad the company that certified my granite put there plate over the section were the weight was defined much heavier than expected


good to see you did a load test for it i work with 1000lb and heavier tool and die plates on our table so if it deflects it will leave a bow in the table thats not a big deflection enough that it shouldnt matter

[jbyrd]

Great, we never would have thought of that.

Does anyone have the template, or specs, for the X cuts? I think are slot is a bit too narrow, and I think there is a larger hole at the end of the X to get the clamps in?

Thanks for such quick replies.

[email protected]

I am utilizing the X-clamp for the welding table I am building. The shank for the x-clamp is 5/8 of an inch. You will need at least 1/32 for clearance to ease sliding. The portion that rides under the table is 1-1/8 of an inch. Again clearance is necessary for ease of installation. I can post a pic of the clamp if that helps.

Jay

[NoogaD]

The welding table I built for my garage shop is very similar. I like the 6" lip all the way around the top. It gives you plenty of room for clamping and blowing holes for vises, bench grinder, etc. The only thing different that I added was a shelf on the bottom. Space is a premium for me, so if it is for you consider adding one at some point for tool box storage, consumables, etc. I also added one of those long multi-plug power strips so I can leave more than one grinder plugged in. I used a 3/8" top. I'm sure those guys using 1/2" are welding some serious iron, but if you guys are doing school projects and personal stuff to learn some basics, I'd guess 3/8" would work for your purposes as well. Keep in mind if you ever want to move it, 4' x 8' sheet of 3/8" weighs about 600 lbs. I made some removable casters and jack up the table and bolt them on to move the table for cleaning, space, etc.