Slotting 3/16" Steel

admin

Hi Folks,It's been a ling time since I've been around. Just do not get a chance to "play" in my garage/shop enough, so just don't stop by as much as I used too...Anyway, I'm wondering about the best way to cut slots in 3/16" steel angle.I am making a base for a motor and would like to add slotted holes to the angle frame to allow me to adjust the belt tension. I am thinking about 5/16" x 1" to 1.5" long slots.Unfortunatey, I do not have a milling machine, but I do have...drill press (and some pretty good metal bits)metal saws and filescutting torch (quite an ameture)mig welderI was thinking of using my drill press to drill either end of the slots and then using a metal cutting blade in a jig saw to cut out the center. I know this is probably EXTREMELY ameture, but it's what I have. Like I say, I do not know that i have the skill to use the torch for this...Any thoughts? Thanks.Weekend MigBackyard MechanicWelder: DECASTAR 150E, Wire Feed w/ Gas Potential (not currently using gas)
Reply:Remove as much material as possible with a drill bit, Then use a saw and file to clean it up.
Reply:Well, that would work.  And with what you have, probably your only option, unless you are very skilled at that cutting torch.  Do you have an angle grinder?  You could drill your end holes, then use a cutting wheel on the grinder to make the cuts.  It would be like using the jig saw, only faster.  How thick is the angle?  A really good way would be to put a burring bit (probably not what it's called) in your drill press, and using a sliding vise..
Reply:What tapweld said X2 ORIf you get yourself a little practice with the OA torch - it would be easy to drill the ends of the slots, then use the torch to cut out the middle (assuming you have hte right tips for metal thicknesses you're using). I've done similar work just with a torch, but it takes some practice.Didn't see an angle grinder  in your list, but that could be used to cut out the straight legs too.GL!MikeWhoops - JC was typing at the same time!Miller Dynasty 200DXHypertherm PowerMax 45Victor OAIR CompressorLots of blacksmithing tools and other fun toys meant to creatively disfigure, reshape, manipulate and join metal.
Reply:You can Hogg-out as much as you can with the drill pres. DON’T DO IT FREE HAND, SETUP A FENCE AND USE CLAMPS TO HOLD THE WORK TO THE PRESS TABLE. Then cleanup with a hand disk grinder, again clamp the work to a bench.
Reply:Yeah, I failed to mention the grinder, I do have one. Not sure why I forgot, 'cause I use it alot. I typically use larger (7") wheels, but I suppose I could go with a smaller one. Originally Posted by JC'sWelding...A really good way would be to put a burring bit (probably not what it's called) in your drill press, and using a sliding vise..
Reply:I'd use a jig saw with a metal blade. A grinder with a zip cut, even a 4 1/2" one will cut quite a length slot, a lot longer than 1 1/2" due to the diameter of the wheel.As for amateur, not in the least. I work in a welding shop and have access to torches, grinders, plasma and I'd still use a jig saw for a one of project like yours. If I've got a bunch I'll farm it out to the machine shop....Mike
Reply:Mrmikey is right on the money.  Drill two holes and connect with jigsaw.  Then use file to clean it up if you have to.  jigsaw won't harden the edge  or possibly warp material like the torch.
Reply:A drill press isn't made to withstand side forces.  I wouldn't suggest using a drill press to slot. Also, endmills don't stay in drill chuck very well. You stand a better chance of getting it right the first time by using a file or saw method.  I assuming you are only talking about a couple of slotted holes.
Reply:I would draw a straight line where you want the slot. then drill small holes on the line, evenly spaced, then drill out holes to the correct width of the slot, then clean it up with a die grinder, file, etc.Bob.Miller Dynasty 200 DXMillermatic 211Hypertherm PM 600In Tool acquisition Mode
Reply:Do it with the torch. Your working with small pieces of angle so you won't waste much. If your not that good then you won't ever be that good if you don't try it on small pieces. Just clamp a piece of small angle, flat or square stock to the angle and drag the torch along it. You need to do these types of jobs so you will be good enough with a torch.
Reply:Here's how I do slots.....fire up the PlasmaCam machine....turn on the compressor, activate the Hypertherm Powermax45....heres a picture of a radiused slot for a part on a recent project...1/4" steel. Took about 1.5 minutes to draw using the PlasmaCam software....and about 30 seconds to cut.Jim Colt Attached Images
Reply:Originally Posted by mrmikeyI'd use a jig saw with a metal blade. A grinder with a zip cut, even a 4 1/2" one will cut quite a length slot, a lot longer than 1 1/2" due to the diameter of the wheel.As for amateur, not in the least. I work in a welding shop and have access to torches, grinders, plasma and I'd still use a jig saw for a one of project like yours. If I've got a bunch I'll farm it out to the machine shop....Mike
Reply:Originally Posted by sn0border88A jig saw in 3/16 plate is a stretch, and im assuming he has to do a few of these.
Reply:Nobody likes a cheater Jim.
Reply:That's some sweet plazma work Jim - unfortunately, I think my project is a bit to small to warrant a new tool in the shop...shucks Actually, I might take your suggestion (Bob) and give the torch a try. I definitely want to learn how to do this better, and this is a small enough project that I can't do too much damage (famous last words). Besides, these do not need to be precision slots - I just need some adjustment room to slide the motor base and then bolt 'er tight.Thanks for all the help guys - I'll let you know what route I take.Weekend MigBackyard MechanicWelder: DECASTAR 150E, Wire Feed w/ Gas Potential (not currently using gas)
Reply:Then im sure that in your wisdom...
Reply:what mtncxrawler said..get some scrpa and practice. use someething as a guide to rest the side of the tip on .that way you get better and get yer job done.
Reply:If I have to do slots that can't be done on the PlasmaCam machine....usually I drill two end holes and use a hand plasma and a straightedge to guide it. If you use a small nozzle (like Hypertherm's Fine Cut) and turn the power down....so you can cut slow....you can get a nice edge with accurate dimensions. Usually just a little cleanup is required with a carbide rotary cutter on a die brinder and a file.Jim Colt
Reply:Originally Posted by jimcoltHere's how I do slots.....fire up the PlasmaCam machine....turn on the compressor, activate the Hypertherm Powermax45....heres a picture of a radiused slot for a part on a recent project...1/4" steel. Took about 1.5 minutes to draw using the PlasmaCam software....and about 30 seconds to cut.Jim Colt
Reply:Wow the plasmacam table sure is the way to do it if you have access to a plasma table. Here in my farm shop I use my drill press to drill the end hole the use my Hypertherm PowerMax 45 and a slot guide to finish the job.Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:Ditto specter! I'd do the same, but the OP only had OA in his quiver...Jim C - That's no fair!Weekend MIG - Go the two holes (or not) and OA route. If it was real thin stuff I'd suggest other wise, but 3/16" is a good thk! This is a great little project to get the torch skills.MikeMiller Dynasty 200DXHypertherm PowerMax 45Victor OAIR CompressorLots of blacksmithing tools and other fun toys meant to creatively disfigure, reshape, manipulate and join metal.
Reply:I know......bringing the plasmacam machine to this thread is like bringing a machine gun to a knife fight. If I was to use oxyfuel to cut a slot in 3/16" steel it would be rather ugly.Jim
Reply:Originally Posted by BobDo it with the torch. Your working with small pieces of angle so you won't waste much. If your not that good then you won't ever be that good if you don't try it on small pieces. Just clamp a piece of small angle, flat or square stock to the angle and drag the torch along it. You need to do these types of jobs so you will be good enough with a torch.
Reply:Originally Posted by farmersammThe best advice so farGet your feet wet.Most importantly, wear a full face shield in addition to your cutting glasses.  When first piercing the metal, slag sometimes can blow in your face.  The chances are greatly reduced if you tilt the tip at an angle away from you when you first hit the O2.Maybe someone here on the forum lives near you and can give you a hand with a plasma torch?It's not what you can buy, it's what you can build.
Reply:An OA torch will do this perfect with a cutting guide. Be sure to use a 3/0 tip, have the hoses where they will slide along with out any hang ups and make sure the torch is perpendicular left and right but slightly angled into the cut, and move as fast as the torch will cut. With the advent of the plasma, torch skills are fast fading. You can cut very intricate designs with a torch if you get good.Most of these are cut out of 12 Ga. and the rest out of 1/8". And no, I don't have a plasma machine. Attached Images
Reply:You can see there are pears on the cactus and there is slots in the horns on the oryx and the sable.
Reply:I QUIT!!!!!!!!!!I get a decent drop cut and I'm jumpin' up and down, runnin' in circles, and just generally acting like an idiotWOW!!!!!!!!"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Wow - thanks for all the discussion. I think I'll give the torch a try - what's the worst that can happen...Weekend MigBackyard MechanicWelder: DECASTAR 150E, Wire Feed w/ Gas Potential (not currently using gas)
Reply:What a bunch of knuckleheads, the solution has been growling, staring at us all the while.Take 3 rods of the correct thickness and cut them to the overall length required. The middle rod, cut so the slot starts and stops at the right location. Tack weld, and finish weld, a light grinding to clean things up. Done. No drilling, blowing holes, sawing, chewing. And you call yourselves welders. Shame.  This site is all about WELDING, no?
Reply:Originally Posted by transitWhat a bunch of knuckleheads, the solution has been growling, staring at us all the while.Take 3 rods of the correct thickness and cut them to the overall length required. The middle rod, cut so the slot starts and stops at the right location. Tack weld, and finish weld, a light grinding to clean things up. Done. No drilling, blowing holes, sawing, chewing. And you call yourselves welders. Shame.  This site is all about WELDING, no?
Reply:Yeah.....I must really be a knucklehead......I don't understand Transits theory on cutting slots either. I guess I just have to stick with cutting them with my cnc plasma!Jim
Reply:Sorry, i'm up to my hips in a power falure, we're running on UPS and back power. l'll make a picture later.
Reply:Ok, the lights are on again.Five steps should do it. And I made the picture in color too. Attached ImagesVisio-Slot.pdf (15.2 KB, 56 views)Last edited by transit; 06-30-2009 at 04:07 PM.
Reply:The original poster was looking for a way to cut slots in 3/16" angle iron.....for a belt adjustment for mounting an electric motor. I'm not exactly sure how your method fits into that requirement.Jim
Reply:Originally Posted by jimcoltThe original poster was looking for a way to cut slots in 3/16" angle iron.....for a belt adjustment for mounting an electric motor. I'm not exactly sure how your method fits into that requirement.Jim
Reply:We haven’t come up with any way with the tools that you have on hand to cut the slot. Now if you need the arm to be an angle then take one more step. Make the bar as described and weld a fourth bar in place to form an angle. I don’t see any need to rip stock to form the bars. You should be able to find stock in the widths you need.  Three pieces of ¼-inch stock side by side is ¾ inches wide. 5/16 x3 = 15/16 or 1-1/16 inches wide and so on.
Reply:I understand what Transit is doing, good idea. But you could do it with a torch much faster if your any good at all, and he should develope his torch skills. I don't even own a plasma but the few times I've cut with one people ooh and ahh about how good I am with it. I'm not good, I'm steady, prepare myself for the direction of travel to be able to cut at the correct speed, and concentrate. You can cut just as bad with a plasma as you can with a torch. Even though I don't have a plasma, I want a plasma. There is too many times they will just do it better than a torch.
Reply:I needed to cut a bunch of slots one time. I had a buddy of mine with a mill make up a couple of templates for me. Basically I just figured the offset for the torch and had him machine the templates 2X wider and longer than the offset.I'd drill a start hole (not required but it made it easier to start than blowing the holes thru), then clamped the template in place or tacked it. Then just start the cut and let the edge of the tip ride the template like you would a straight edge. Grind off the spots and move to the next and so on.With a bit of practice you can make some very nice repeatable cuts. I've also used the same basic trick to notch for beams and angle, using a thin chunk of scrap as the template (you will need to fill the kerf) or use the scrap to make the template and the fit will be tight (sometimes too tight if you don't do a bit of clean up on the template). Attached Images
Reply:I was rereading the original post and the bracket is a one of a kind effort. I can understand using a jig for multiple units. If weeks OA skill is not up to the task he’ll get lots of practice, the same goes for building up the arm from smaller stock using Mig. Just depends where you want to put the effort.
Reply:Originally Posted by Weekend Mig. . . I am thinking about 5/16" x 1" to 1.5" long slots. . .
Reply:Here is a re-creation of a motor tensioner I once built.  This is a crude drawing, but, the rod is a threaded rod that has one end welded to the upper frame, goes through a hole in the bottom frame, and then has a washer and a nut.  The bottom motor mount frame gets welded to the chassis, and the top is free.  The other end opposite of the threaded rod is hinged.  As you tighten the nut, it brings the top down and tightens the belt.  You just have to have clearance for the rod, or reverse which end of the rod is welded to.  Weld it to the bottom frame and have it going through a hole in the top frame.  Same principle.  Worked for me. Attached ImagesLast edited by JC'sWelding; 07-01-2009 at 03:52 AM.It's not what you can buy, it's what you can build.
Reply:Lots of good suggestions here, but let's back up and take another look: Originally Posted by Weekend Mig. . .I am making a base for a motor and would like to add slotted holes to the angle frame to allow me to adjust the belt tension. I am thinking about 5/16" x 1" to 1.5" long slots.Unfortunately, I do not have a milling machine, but I do have...drill press (and some pretty good metal bits)metal saws and filescutting torch (quite an ameture)mig welder. . .
Reply:it isn't rocket science.  use a cutting torch and dress it up with a burr bit if you need to.
Reply:Thanks for all the great discussion, but it's all done, and here's the update...After all the disscussion, and deciding to go the torch route, I found out last night I was low on oxygen. So, I went back to my original idea of the jig saw. Unfortunately, you'll see from the photos, my jig saw is an oldy/cheapy single speed. But by taking it easy I was actually able to cut all 4 slots without burning even one blade (I had extras just in case). Cuts are not the neatest, but a little filing cleaned them up.Besides the angle grinder, I also failed to mention I have a steel cutting chop saw as well - which I used to cut the angle from the stock. I also substituted light motor oil for cutting oil when drilling. Seemed to help things go smooth and not get too hot.So, although some of the techniques and result are not "machine-shop quality", the result was what I wanted... Attached ImagesLast edited by Weekend Mig; 07-01-2009 at 08:33 PM.Weekend MigBackyard MechanicWelder: DECASTAR 150E, Wire Feed w/ Gas Potential (not currently using gas)
Reply:More progress photos... Attached ImagesWeekend MigBackyard MechanicWelder: DECASTAR 150E, Wire Feed w/ Gas Potential (not currently using gas)
Reply:And the finish...Thanks again for all your suggestions. Attached ImagesWeekend MigBackyard MechanicWelder: DECASTAR 150E, Wire Feed w/ Gas Potential (not currently using gas)
Reply:Those look great!It's not what you can buy, it's what you can build.
Reply:Well done!Miller Dynasty 200DXHypertherm PowerMax 45Victor OAIR CompressorLots of blacksmithing tools and other fun toys meant to creatively disfigure, reshape, manipulate and join metal.