Building a small portable cut table that comes apart for storage.
Specifications: Sounds like a while before might see- in the meantime building a burn table, well a small platform to cut on. This will be very cheap, simple quick & dirty to start. Eventually though... Id like to build a nice work table for welding on, open grate section to capture/contain bulk of metal cutting. For cutting with the plasma cutter, and gas torch. I'm seeing also incorporating vise allowing to cut over grate when using sawzall etc. And allowance for setting the chop saw on it...
Primarily started out just planning a simple surface to cut on with new plasma, quickly grew into to what I would like build. No limit to versatility and features that could be combined...whoa.... Basic would be a can or drum with a grate on top. Table frame with funnel under grate for collection next. I haven't got a plan though because of the options and what I could do. So I am forcing my self to start with a small square frame with slats. That will allow cutting. Then Ill think about adding simple legs and something for collection. Also allow time to scrounging material or get to metal supply yard. For frame I was going to use 1 1/2"angle, slats I was going to use 3/16 x 1 1/2" flat bar which would be removable. As I am buying materials, all that went out the window because of cost. Rebar is dirt cheap, as this at best is temporary, just not spending a lot. Going to hardware store to pick up angle for frame saw some bent angle with holes. Its pretty light stuff but cheap. However the holes are Ø7/16" spaced 1" apart, would allow fitting 3/8' rebar-instant frame, pre spaced. So picked up 20' 3/8" rebar. 6' of the 1 1/4" perforated bent angle. Nuff of the intro.
Lay out small cut table top Then laying out to cut realized material bit on the short side. So laid out by maximizing material cut lengths, mostly rebar to get size of table.
Spacing for width, I can get enough rebar to fill 14 holes cutting into 17" lengths and have a reasonable size table.
Made my head hurt. Will let me make a 16" square opening. Plenty to cut angle, it for the present will leave 2 unfilled holes. Overall table will be 18 1/2 sq. The rebar will simply insert thru frame holes. Fixing in place, not sure. I 'think' I'm going to tack on small length of round bar to ends of rebar, they will poke thru holes in frame. I could tack weld, simpler. Could drill and use pins..which would be nice more easily removable.Then I could move center bars when using chop saw so not unnecessarily building up slag on bars? TBD But I have lengths to start cutting. Cut the rebar into 17" length, and angle pieces to length. Couple of unresolved problems. before I can weld the frame. The grate will be 1/4" below edge of angle. Probably just cut up some 6-8" pieces of 1/4" round bar, bend into shallow arcs and throw on table. Might also extend life of rebar. But I'm still up in the air on the ends of table. Reversing the 2 sides angles with horizontal leg on top as shown would give more support for long material, be easier to add legs if I do. But make the corners kinda funny? Because of material length I'm committed to the 2 long and 2 short lengths so cant miter. In case you didn't guess I'm planning this as I write, wingin it. Have no idea how I'm making a catch basin or legs. Frame cut & welded. Decided to stay with original plan.
Makes the frame a little stronger as it boxes the corners. Be easier to lay long material-lends itself to more leg options. Cut the rebar and inserted. This would be a lot easier using real angle and flat bar...so far I've got $7 dollars invested though.
Eyeballing the capturing of rebar. I'm welding a piece of flat bar to sides, center spanning underneath rebar. Mostly thinking the rebar might sag once hot. Also realized, possibly later, flat bar slats, thin, might be used, notching ends to fit thru angle holes.
For now I'm just trying to get some ideas for easy containment of the rebar. I 'think' I'm just going to weld piece of 3/16" rod, across one end, to outer rebar rods, actually make a long 'U', plug weld onto angle as a stop. On the other side, make the rod removable so I can slide rebar pieces out as wanted.Something simple, just waiting for it to gel Ground out the frame.
Started looking at legs. I want this to be easily disassembled for storage/setup. Plan sort of is simple tube with nuts welded inside that will attach to frame. Though square tube so its captured inside of frame. To it weld legs with cross brace. Cross brace should end up at height to support shelf that catch bucket will set on. And budget went out the window/ Being in a hurry went to local hardware. I appreciate the convenience so when I just need small piece of metal I pay the extra. Otherwise any real quantity quickly pays for the 30mile trip to metal supply.
Material for legs: The 3/4" legs will be welded to the 1" tubes after top tubes are fit inside top frame. Fitting the top tube into frame. (16" between top angle legs minus 2 nuts=15 5/16")
Cut 1x1 to length, weld in square nuts, they are offset to match hole in frame. Places tube against inside corner of top angle.
Shown upside down, set in top spreaders in frame, run bolts thru top angle with nut on back side and thread into top spreader. Ill face off ends of top tube later. Rotating inside nuts until bolt threads thru and into top spreader without binding-hmm bit of fun, tack weld nuts in place. Remove to spreader then weld nuts to frame. These hold the bolts for mounting legs so they don't need to be completely removed and also spaces top spreader from inside frame corner welds.
Next assemble legs. In my infinite wisdom I decided that broaching the legs and inserting the mid spreader would be a bit stronger than simple butt welding. Second set of legs, shown, I drilled small holes in corners to help with 'broaching;. 3/4" stroke with square file wasn't fun
Fortunately material is thin.
Just had to see...loosely sat the top spreader on top of legs, sat table on top. By golly this might work...Nice, originally legs were to be welded to outside of top spreader/mount tube. Liking the appearance decided to put underneath. (this would bite me big time later when I went to add the chute, because I simply forgot WHY the legs were to be on outside).
Welded the spreaders to legs. Then looking at the square nut inside the 3/4" tube for the levelers, not a lot of weld...square nuts are only 3/16" thick.
So changed to hex nuts for a bit more penetration and contact and one more thread.
Last one. Little bit of grinding, and sand it out.
Oh I have a plasma coming- I could cut a pattern into the flat bar. Could just add some opposing diagonals, pivot on one leg and bolts to other, simpler, self storing. Anyway to be done. The bottom shelf, originally it was going to just drop in but Ill make it so it captures the leg spreader bars, notched around the legs for resistance. Between it and the side plates should suffice. This making it so it breaks down and still solid a head scratcher...details Unless using dictates fixing-the rebar I'm leaving loose so I can add remove as many as needed for given project. Leg stabilizers Ahh...been round & round trying to come up with stabilizer. I ended up using flat bar X'ed. Because of 36" piece I want to use, 10" height is most I can get. Hopefully enough angle/spread to stabilize between leg sets. If X welded at center would offer a bit more resistance. Not sure where it came from but looking at how to easily attach stumbled on some old strap hinges. Thinking hinge X to one side would mean 2 less bolts, but more importantly it will be self storing-. Then tabbing the opposite side, though mostly to utilize material. The X at 10" height, 16 1/4" between leg sets, need (2) 19+" from a 36" piece. of material. Tabbing makes it work, plus with offset of hinge X will be centered in legs. Screen capture of rough cad drawing working out numbers
Well that's the plan. Because the table legs moves, making this up as I go, to actually make the "X" brace I ended up tapeing paper to work bench, drawing full size picture of 2 legs- 16 1/4" apart, and 2 lines 10" apart between. Cut and fit all the pieces one at time. lay on drawing then on to next piece. Not so fun- a lot of pieces, many back forth between patterning, chop saw, weld table, table itself, but we got it. Took forever, this simple fold up table is a royal pain. Can not tell you how much I wanted to just weld it out and be done. But I don't have room for another stand. Once done will be nice, enjoy the fabbing and puzzle solving but this thing is silly.
First thing I did was peen the hinges to get rid of slop Laying hinges on newspaper pattern with the hinges 10" apart started laying out angles to cut flat bar pieces. Started with the long X leg, cut on the chop saw. Round and grind then lay on pattern. Cut the 2 tabs out, placed on pattern. Then cut the other leg of X, it will be 2 short pieces and the X will be welded together. With all the pieces cut, now to figure how to weld. Decided to start with the long X leg and weld to a hinge, too many loose pieces.
Hard to see but tacked flat bar to hinge, weld to barrel. I cut off excess with sawzall then fully welded bar to hinge. Lay back on pattern. Welded short section of X leg to the other hinge. Tricky part aligning so hinges don't bind but more drilling holes to match tabs. I ended up clamping hinges to legs. Use magnet to hold tab, once lined up I used a small clamp to hold the tab to end of X leg. Took to drill press and drilled hole, broached the hole and drove in carriage bolt. Secured with a nut. Then check against table. Hey it still fit. The other tab will be last but I need to weld the short X pieces to the long X.
Marked everything while clamped to legs, then removed, laid the pieces on the weld table and welded the X to together.
Simply nice. Leaned against the table, rock solid. In fact so much I'm not doing the other side as I planned. It would be way easier to do remaining side because I can work directly on table now instead of setting up and jigging 15 times. Now I know it works, have a clue probably take a half an hour to recreate, so maybe later. Table does want to slightly twist to the back side but once bottom shelf on, which will capture the cross brace on legs it will stop twist between the legs sets. Alternatives thinking about it, could just do tabs instead of the hinges. Hinges seemed like a good idea due to welding the X and storage but if the X isn't welded together the individual bars can just hang when broken down. The whole point is this table will easily fold up for storage. Dang it! I just looked, I have another pair of old hinges...hmm-. As I likely will use chop saw on this if I follow thru on the collector chute stronger is better. Could have done in the time spent thinking about it.... For now just clean up the welds, ground & round it all. Wire wheel it all again as its starting to rust. want to get some paint on it.
Painted! Had some old colonial red I haven't been able to get rid of. I hate red- Perfect. Did get the center spreader welded under rebar before painting. Scrap 1/2" tube turned at 45°, yup it got painted, it only stink for a little while.
But painted. After I add back brace, probably a holder for plasma torch head and burn some metal, down the road repaint will see a color change. Though picture shows a bright red (flash) its a fairly deep dark red, not bad. At any rate interesting project.
To do: to be continued-actually using the plasma..This table will likely be on ongoing project, adding stuff to it, clips & holders etc once I start using machine.
Since all the stuff was out-bugging me that I stopped short-so finished the back brace. Bit of clean up, obviously didn't get the paint as cleaned off as I thought. Hinges welded on fine as I wiped with acetone, but the tabs I just scraped paint, weld splattered pretty bad. They are welded but not pretty, course nor is most of it-anything else I would have ground out and rewelded- Oh well, clean it up, match drill the tabs. Surprisingly did get rid of most of the twist. Will no longer fold completely flat, Xs hit opposite bottom tabs, should have raised the added X an inch-just didn't see till it was welded out.
Building the hopper Can be seen here at Brake build page do-doo do doo do dah...intermission music- 2 days later back on the plasma table....
Cut 4 strips 18" lg x 2 1/2". Intent is to bend one side full length to match angle of chute/hopper sides to be riveted to it, with a 1" flat to mount to table, last 1/2" bent to 90° just to stiffen.
Quite a bit of trimming, match drilling. However had to back track. When I drew out the leg assembly to get numbers I decided to move legs under the cross bar instead of to face as planned, look better and a bit stronger...
Its coming along-when I get a minute I work on it-but I have couple of months before cutter arrives so no rush. Did decide to nix the shelf for collection container-pretty sure just a can that hangs.... Need to cut disks and weld half loops to them for the feet. Shelf for the cutter, then again I'm also thinking just flat bar bent at ends, spanning over leg spreaders to support the cutter. Definitely adding short piece of flat bar with nuts welded at end and riveted to top flange, use thumbs screw for holding chute instead of the small c-clamps.
Just a picture in the sun.
And the whole reason this ended up a bit more effort than really needed for a simple table. Ability to fold up for storage.
And where it will live. It takes couple of minuets to set up.
Few days later-pause The chute just seems it might be really too shallow- I can only hope it lasts a while. If I had used 12" instead of 10", 'think' might be more survivable with greater angle of sides. At any rate it was assumed/planned and considered a consumable like cut bars, replacing chute when if needed. Next one though will be deeper-so I need to figure that allowance in for catch tray.
Unless.. and the reason I stopped while adding the flat bars to attach chute....in the back of my head it would be easy to fold up a say 4" C channel, place between chute an top, to drop the chute further away from molten metal...now that I'm pausing, It might be worthwhile doing before adding the flat bar attachment. Did realize when I made bent flanges for chute I could have made taller to accomplish same thing, hindsight. Need to ponder. Found out the cutter is delayed another 2 weeks out- adding the drop may allow longer chute life.... And apart it comes
More I looked at it the more I didn't like how close the chute was to top. Overall its 8" deep. Ended up drilling out the rivets, separating the mount flange from chute. Decided be easier to make a piece to space between and reuse top flange instead of making another mounting flange. Cut 4 pieces 4" wide, 1" bent flange to rivet to chute, 3" up to attach to rebent the top flange lip (that was riveted to chute) to 90°. Easier said than done..
Stuck on the collection tray. I WANT to add a shelf underneath for tray, I also want to add a shelf under that for cutter to set on, though that might not be a good idea due to dust. But the tray- nice would be something like a tin can that can easily be replaced. Id like it to hold water. Coffee can not big enough OD, needs to be a large OD but on 4" deep-. Still waiting on cutter to arrive, -------------------------------- A big part of this build was a proof of concept, large part investing least amount of money. The other is I'm trying to design/build something for something I've never used. Lastly its just something that I can immediately use to start cutting on and wont take any floor space. Could be this whole top & chute fails, either rebar burns out too quick or slag sticks, thin 12ga sheet chute instantly burns thru or waste doesn't flow...don't know. But I'll find out. Unless materials I used work, but bottom line temporary. The folding stand/ leg assembly though does work, so will be re useable. More later-If I add...
Made some washered thumb bolts. Well tacked on washers and added small piece of flat bar to existing bolts for 'tool less' use. Welding thumb tab across 2 flats still allows access to 2 pair of flats if wrenching needed. They only need to be finger tight for function but just in case. Update: Plasma cutter finally arrived, cut out the disks for the feet. Plug welded some half links.
Table works pretty nice. Found I only use 3 or 4 rebar rods. Temporality I've been setting a small plastic trash can with a couple inches of water on what ever to get it to hopper bottom. Works ok-need to find a metal can and make the shelf which likely will be just some bent 1/4" round bar that sets on leg cross bar. Also need to make a small expanded metal screen for when cutting small parts off larger material. That and something to hang/park torch head...details. The original idea of mounting a second shelf below to hold cutter isn't happening. I did not know how much dust the plasma generates-want the machine as far away as practical. Thats my table Back to Our shops tool mods section
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