Work clamp

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So I spent some time tonight getting tooled up for the morning. I needed a clamp to hold down some castings for a drill operation. I have an old fixture but I hated it. I almost sacrificed a Bessy clamp.  But instead decided to make one purpose built.I've never made a clamp before so I started by turning a ball on the end of a piece of 3/4" all-thread. I then drilled a piece aluminum bar. I was worried the bottom of the hole wasn't rounded and I almost ran a ball end-mill down the hole to round it... but the ball ran plenty well on the angled drill nose bottom so I left it. I then machined a groove for a snap ring... but after looking around for the correct snap ring I decided to widen the groove and use an o-ring keeper. The o-ring worked well because I greased the ball and it keeps in the grease. Fortuitous. After I welded up the arm I decided it needed a little bend to get it where I wanted and clear the quill. I originally thought I'd weld a T handle on the all-thread but I was afraid it wouldn't clear the quill so I welded a nut on instead.  Hand tight is all that's needed anyway.  I also made the aluminum pads to support the casting without damaging the machined underside.So before your tempted to cut up a clamp... maybe you should make one.  Attached Images
Reply:Very nice! I will suggest one change. The plate steel, arm, welded to pipe post. If expanded, gusset style, as to be welded to post and base, would prevent distortion that will develop in current configuration after repeated use.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:That is a nice fixture you built, you must have a lot of those to drill. When I make a shoe for the balled end, I groove it and go to my supply of springs and find one a little bigger in diameter and cut out one coil and it works perfectly. Nice job as always.
Reply:Originally Posted by waginVery nice! I will suggest one change. The plate steel, arm, welded to pipe post. If expanded, gusset style, as to be welded to post and base, would prevent distortion that will develop in current configuration after repeated use.
Reply:Nice setup! When it comes to mill work fixture, fixture, fixture and then fixture some more! and then progress starts to happen.LarryMiller XMT 304 CC/CVSyncrowave 180 SDLincoln PowerMig 255XTTermalDynamics 52Lincoln 305GComlpete machine shop to back it up
Reply:Very nice work
Reply:I've used a piece of coil spring to replace the ring on the end of a impact before. It's worked fairly well (part of my problem is some cheap sockets are loose on it).  I like the o-ring idea myself and will have to keep that in mind.   BTW McMaster Carr sells replacement swivel pads for clamps. I've used them and they're pretty good.  Oh yeah. Nice work as always.Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm
Reply:Nice job. I'm lazy, I keep a bunch of HF c clamps and vice grips to cut and weld for one offs.PeterEquipment:2  old paws2  eyes (that don't look so good)1  bad back
Reply:Originally Posted by castweldNice job. I'm lazy, I keep a bunch of HF c clamps and vice grips to cut and weld for one offs.
Reply:One word of warning on the replacement pads. Don't put them on till you put the screw through the nut. They don't come off nearly as well as they go on. I made a bunch of replacement screws for some good brand C-clamps a local welder had. The original where brass and standard 3/4" V thread had worn out. I used grade B70 threaded rod turned the balls on the ends and welded a nut on the top to make the replacments. I made a extra because he was sure he had another frame somewhere. My helper decided to help me and put the pad on the extra. I've still got it but I'm not sure how I'm ever going to get it off without damaging it. Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm
Reply:A little heat With a small rose bud on the pad might help it pop off easier. If these clamps are for a welder, then they will eventually have tons of heat on them anyway, so a little now wouldnt hurt.
Reply:Job well done! I hate being bi-polar it's awsomeMy Heroes Have Always Been Cowboys
Reply:question for you forhire, are those tops for a mini-centrifuge?Classic 300D LN-25Plain Jane O/A
Reply:how did you turn that ball end on the all thread?  you have a ball cutter/turner?
Reply:Originally Posted by Lincolnguyquestion for you forhire, are those tops for a mini-centrifuge?
Reply:Thanks, been looking for a centirfuge to clean WMO and thought they looked familiar.Classic 300D LN-25Plain Jane O/A
Reply:I'm back drilling holes today. The large nut with the hose on the clamp just isn't cutting it as a handle!  It makes my hand sore.  So I escaped to the office (where it's nice and cool ) and designed a new handle. Nothing fancy... but just what I was dreaming of during the last few dozen parts. Whipped it out on the cnc in about 5 seconds... and welded it on. Broke the edges with the die grinder. It will get complete test tomorrow.  Attached Images
Reply:DOH!!Wish I had seen this earlier last week. I had to sacrifice a bar clamp (not a high dollar bessy tho) for almost the same type of set up. Looks good man.  I am gonna file that away in the grey matter cabinet for later use.One question tho, how did you get that radial groove in the plate? I am gonna guess you cut it into a plate on a lathe then cut the plate in half ?If you cant fix it with a hammer, it must be an electrical problem."Boy, everyone starts with a full bag of luck and an empty bag of experience. The trick is to fill the bag of experience before the bag of luck is empty."-Grandad circa 1990ish
Reply:Originally Posted by larpheadWish I had seen this earlier last week. I had to sacrifice a bar clamp (not a high dollar bessy tho) for almost the same type of set up.
Reply:The twist clamp, especially with the new handle is great, but I'm in the middle of production... and it is too slow. Tonight I built a toggle clamp to replace the twist clamp. I got the idea after seeing some wood ones online. Not fully understanding the mechanism I kept the geometry similar to the wood ones. The next ones I build will be scaled up slightly but overall this design worked. Here's the URL:http://www.cnczone.com/forums/diy-cn...holddowns.htmlI started by modelling the part in cad and cutting all the parts on the plasma table. I ended up making it higher and deeper than I really needed... but I just copied the existing clamp height... knowing it worked. I did have to get creative and bend the arm a bit in the press.I didn't model the stop block... I just didn't understand the function until after it was assembled. It keeps the cam from passing over center. Duh! I found a piece tapped rod with a set screw in the bolt bin.Worked perfect and it's adjustable.I'm sure I could have bought a toggle clamp but I needed it today... so I built one. Works great. I learned a lot about clamping mechanisms... well worth the few hours spent. Attached Images
Reply:After using the toggle clamp for a few parts... it became obvious it needs a good handle. I had the handle from an old Makita drill. Works perfect and keeps your hands clear of the spindle.  Attached Images
Reply:You know enco sells those toggle clamps and they're cheap....Is that a glacern chuck?My name's not Jim....
Reply:Originally Posted by BoostinjdmYou know enco sells those toggle clamps and they're cheap....Is that a glacern chuck?
Reply:Grizzly was my second guess.  I haven't bought anything from glacern, but I have eyeballed their integrated R8 chucks a few times.  I've just been buying cheapy keyless chucks off ebay for the lathe tail stock.  I do need to get a good one for the mill as a backup.  I'm still using the bison or whatever it is that I repaired a while back.  It still locks up tight and spins true.My name's not Jim....
Reply:Forhire I really enjoyed watching the evolution of the perfect clamp for the job.  I imagine you fitting piece after piece into the current version and noticing stuff that you didn't like (sore hand, time taken) and thinking about a solution for the next few pieces then you reach a point where the current version has paid for itself, you have mulled over the solution, and it just has to be made.Thanks for taking pictures along the way and posting.Miller Syncrowave 180SDLincoln WeldPak 100 with gasHandheld Milwaukee BandsawO/A Cutting TorchGreat ideas showing good imagination!  But how many of these centrifuge covers are you making, anyways?- MondoMember, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:Originally Posted by BHereForhire I really enjoyed watching the evolution of the perfect clamp for the job.  I imagine you fitting piece after piece into the current version and noticing stuff that you didn't like (sore hand, time taken) and thinking about a solution for the next few pieces then you reach a point where the current version has paid for itself, you have mulled over the solution, and it just has to be made.Thanks for taking pictures along the way and posting.
Reply:"Necessity is the Mother of Invention..."
Reply:Boatbuoy, your care package arrived. Thank you! I've been playing with them. Very neat. Now I need to figure out the best way to mount the clamp. Anyone have any suggestions? Soon we'll have push button speed.  Attached Images
Reply:Those look pretty neat.  Pneumatic?  Do the things that look like fingers in the top right swing up and out of the way and down to clamp?
Reply:If you find you need a toggle clamp quickly, see what you have for woodworking stores nearby as they typically carry them.  A really good hardware store will probably have them too.  Destaco-style clamps are pretty common in a number of sizes.Nice work.  I can see how you might want to go pneumatic with that for the long run. All you would need would be an air cylinder with a foot pad on it pushing directly down since you said the original thumb screw version only required finger tight.  Shouldn't take but a tiny cylinder for that.  Perhaps a foot switch for it too.-DaveXMT304 with: 22A Feeder, or HF251 Hi Freq DC TIG air cooled
Reply:mounting can be done with those empty holes in the head.make a bracket to fit that gap. you'll be surprised at how much force is generated byy those small clamps. i believe its more than a ton.miller thunderbolt 250vlincoln square wave tig 175 prolincoln idealarc mig sp250everlast tig 210EXTeverlast power plasma 50chicago electric (hf) 130 tig/90 arcchicago electric 90 amp flux wire3 sets oxy/acet
Reply:This is a great thread!  Many ideas.  Thanks.Jerry30+ yrs Army Infantry & Field Artillery, 25 yrs agoMiller 350LX Tig Runner TA 210, spool gunLincoln 250/250 IdealArcESAB PCM 500i PlasmaKazoo 30"  vert BSKazoo 9x16 horiz BSClausing 12x24 lathe20T Air Press
Reply:I have a Siegmund fixturing table and all the pads are held on with a similar setup as you wrote.   An O-ring.  It is nice because I can change out pads for pipe or flat.   Just pop one off and put another on.
Reply:nice clamps, you probably already know they need some air restrictors to slow down their movement. you will love them
Reply:nice job as usual f.h. it's amazing how a simple clamping idea morphs into something more complicated than the paying job. great post.i.u.o.e. # 15queens, ny and sunny fla
Reply:Originally Posted by snowbirdnice clamps, you probably already know they need some air restrictors to slow down their movement. you will love them
Reply:Originally Posted by storemanThis is a great thread!  Many ideas.  Thanks.