Theres Must be Some Type of Bolt or Nut to do This

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I have 4 dock bumpers to mount some how. They have been welded on several times before and keep falling off so I cant just weld them. They need to move a little when the trucks hit them. they really need to be bolted on but my problem is a guy before me welded a quarter inch thick plate to the dock because the concrete block wont hold them. Im trying not to have to cut the plate off and either weld studs or nuts to them. I need some kind of bolt than can slip behind the plate and hold. Attached ImagesHobart 140Victor O/P (really want a Smith)
Reply:Do you have a photo? I can't really tell what's going on based on the drawing.Can you drill into the plate the diameter of a nut and weld the nut in the hole?Last edited by forhire; 01-05-2013 at 08:50 PM.
Reply:T nuts or T bolts come to mind. The problem would be installing them. I could see making a larger hole above so you could slip the large portion of the nut into the hole and behind the plate, then a vertical slot down to hold the nut securely.  On a mill this would be easy. In the field with only a torch or plasma and no access to the back to remove any dross I can see this being a lot more difficult. A mag drill to drill out a larger entrance hole and maybe a smaller hole at the bottom, and then a slitting wheel to cut the sides of the vertical slot.Toggle bolts might be an option. drill the steel, then use a punch to bust the block so the toggle can grab the plate. One other option would be epoxy. Hilti makes a screen sleeve designed to hold in hollow block. You drill the hole, insert the screen sleeve, then fill with epoxy and insert the stud. The steel/block combo will make drilling the holes a PITA. Drill too deep and hit the block, and you'll toast your bits. Catch the edge of the steel with the carbide masonry bit and you'll either go for a ride, or ruin that bit... I'd oversize the holes in the steel myself if I had to go this route.Drill and tap comes to mind as well..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I thought about cutting a slot and putting in a bolt i just couldn't think of the type of bolt to use thanks DSW. I also forgot to mention it needs to be 3/4 in dimater and i cant find toggle bolts that big anywhere and i don't think a quarter inch of thread could hold just the dead weight if the thing much less a 80,000 pound truck so drill and tap is out.Hobart 140Victor O/P (really want a Smith)
Reply:Awsome work wth the architceral drawing, all we needed to help was a few stick figures  I hate being bi-polar it's awsomeMy Heroes Have Always Been Cowboys
Reply:I am like Forhire not really understanding the drawing. Can you weld small plates with threaded holes onto the exixting plate. 1 inch plate say 4" x 4" with holes drilled and threaded before welding them on. Just a thought.
Reply:Key hole slots?Thermal Arc 210 FabricatorHypertherm PM 45and lots of other tools the wife doesn't know about
Reply:Originally Posted by weldermikeAwsome work wth the architceral drawing, all we needed to help was a few stick figures
Reply:3/4" bolts will certainly complicate things. How much of a gap is there between the steel and the block? I'm betting even if you can find 3/4" T bolts you aren't going to have the room to use them. You might just have to make your own, by welding a plate to a standard bolt head.Honestly I don't see you needing bolts that large. If this is what I think you are doing, the bolts simply hold the bumpers in place. The stress is all in compression not shear or tension, so the bolts are sort of non load bearing even if the truck weighs 80K. If that was the case. I'd see the 1/4" plate failing way sooner..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by rockcrusherr430I do allot of CNC machining so i know my way around cad/cam software i just couldn't figure out how to get the picture on here.
Reply:Originally Posted by DSW3/4" bolts will certainly complicate things. How much of a gap is there between the steel and the block? I'm betting even if you can find 3/4" T bolts you aren't going to have the room to use them. You might just have to make your own, by welding a plate to a standard bolt head.Honestly I don't see you needing bolts that large. If this is what I think you are doing, the bolts simply hold the bumpers in place. The stress is all in compression not shear or tension, so the bolts are sort of non load bearing even if the truck weighs 80K. If that was the case. I'd see the 1/4" plate failing way sooner.
Reply:Originally Posted by Rkott4Key hole slots?
Reply:Could you not weld nuts to the outside of the steel pâté and counter bore the back of the rubber bumpers. Then use 3/4" bolts of the right length?
Reply:rockcrusher340I have installed 100's of: dock boards, dual docks, edge of deaths, and countless bumpers - roughly split between new construction, and replacement.Replacing bumpers can be especially difficult, primarily because of original design and construction flaws.Reoccurring bumper failure is usually due: to inadequate corner steel, mud-hook size, length, and placement; and nonexistent facial anchor steel.  In the Material Handling field, architects are infamous, and held in distain, for their lack of attention to loading-dock dimensions and structural details. The original installer can only attach to what the builder has provided.If the architects specifications are lacking, the typical installer is:going to get it done, get the check, and get gone.  It is one thing to repair something of original integrity.   It's quite anotherto repair something the was designed to fail, but this is the condition you are facing. Every situation is unique, and can be reparated: please post hi-def pics, from all angles, and I'll will help if I can.Opus
Reply:You are overthinking this. Weld studs to the plate. put the dock bumpers over the studs, put on a rubber biscuit, then a washer, then locktight the nut on.
Reply:ditto on the weld studsVantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:These guys are fastener experts. Look here and see how others have done a similar project.http://www.us.hilti.com/holus/Lincoln SA200's... at least 15 - 20. They come and go. Growing partial to the "Short Hoods" in my old age. Last count on Short Hoods was 13 in possession.
Reply:Get a couple of used automobile coil springs at the recycle yard.  Cut 'em so you have only about 2 full turns then weld one end to the plate on the building and the other end to the back of the bumper plate with an 8x8 wood block bolted to it.  Do this in pairs on each side.  When the truck hits the bumper the springs absorb the shock.  Leave 'em full length and when the truck hits the bumper it gets rebounded back across the lot with a snap!  The dumb-@$$ driver won't hit it so hard the next time!  i didnt say any of this.   someone else hacked my computer.
Reply:When I was 15 years old I worked for a guy that took care of a chain of Supermarkets during my summers, we capped a concrete dock corner with a 10' 12"x 12" angle iron bent at the local steel house. I took welding in school so he thought I was some kind of master welder and from that point I started doing all the welding, man was I nervous. In any event I welded the rubber bumpers on ,they had metal angles at both ends, welded them vertical up with a Lincoln Weldanpower 130 AC machine. I am 50 now and they are still in place today , take my sons by there now and then to laugh at them.  why do the trucks tear them off, are they hitting them sideways or something?"Si Vis Pacem Para Bellum"Lincoln Idealarc 250 AC/DCMillermatic 251   Syncrowave 300   30A spoolgunLincoln MP210Hypertherm 45(2) LN 25(2) Lincoln Weldanpower 225 CV(4) SA200   1 short hood    SA250    SAM 400