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So to all Millrite owners. I can not find a clamping kit that gives exact dimensions of the T nut. I''m told the Bridgeport labeled kits will work. I have checked and NO they do not fit. I have a base of 1.190" top slot of .680" and the holding area below slot is .400" overall height is 1.050" Bridgeport T nuts with 1/2" stud bolts have a base of 1.250" mine are 1.190" exact. Can someone tell me what kit to order. Making T-nuts does not excite me plus I still need the step blocks and studs.
Seems if the rest of the dimensions are ok, it would be pretty fast and easy to setup to mill the t-nuts narrower. With all the drilling and tapping, making them is a bit of a pain, but just modifying them, should go pretty well.
As long as the blocks are not hardened. I found out the hard way about angle blocks when I tried to modify. Also my reason for posting about 123 blocks. Most adds about this stuff is vague regarding dimensions and hardness.
My thoughts exactly. Mcmaster Carr has individual Tnuts that are pretty close. I think I'll grind the bottom width by only .040" on each side the rest will hold nice. Anyone want some unusable Tnuts for a Bridgeport when I buy the set made for BP LOL.
The t-nuts with my clamping kit either weren't very hard, or I may have used carbide. Either way, I did modify a few to fit my rotab which has narrower slots than the mill table. Send the extra t-nuts my way! That's one thing that you always have too many of until you don't.
I bought a Te-Co set from Enco many years ago that works perfectly with my Millrite without modification. The nuts are: 1" base, .62" step width and the overall height is .625". The bolts are 1/2". You don't need or want T-nuts to fit very close in the slots, that just makes them hard to move/position with a few chips in there.
I make my own t-nuts for all my machines and fixtures, including my Millrite table. I make them out of mild steel to fit the slots to a snug fit, and after they are made to size I carefully round all edges and corners and check all flats, removing all burs and sharp corners. My Millrite came very slightly used, and the t-slots of the table are part of the de-facto precision of the machine, along with the table top. I find it really annoying when dings and burs in the t-slots and table top slow down building setups. I have found hardened t-nuts with factory sharp corners and burrs to be highly annoying and damaging to the t-slots.
Making t-nuts is quite easy. Machine a length of stock to the required width and height, cut the two notches that make them T-nuts to size, drill, tap, and chamfer the holes, remove from the table and debur all of the corners along the length of the stock, and only then cut them into individual t-nuts. Finally, debur the ends of the t-nuts and inspect and clean up any other roughness and burrs. T-nuts that properly fit their slots are much faster and easier to use. While you are at it, make a t-slot cleaner that truly fits the t-slots of the machine, and use it regularly to keep the slots clean. You will be amazed at how much faster and easier setups become with the proper fits.
Also use a punch or chisel to deform the threads at the bottom of the T-nut so that a bolt cannot screw through it and bear on the bottom of the slot. This eliminates the risk of jacking the nut and breaking out the slot.
Like anything in our shops your going to get what your willing to pay for. I do know the Te-Co clamping kits are hardened to where I wouldn't want to try milling them. Unfortunately it seems the price goes way up for anything larger or smaller than the standard BP table slot size. But as already mentioned a belt grinder should work if there's not too much to remove. I haven't checked for sure Te-Co offers anything that's a direct fit for your mill, but there web site does list dimensions. https://catalog.te-co.com/category/clamping-kits Fwiw I ordered an off shore clamping kit to fit the 12 mm slots in my lathes cross slide from LMS. Let's just say they at least look like a clamping kit and for the amount of use they'll get are probably good enough. But every thread had to be chased to remove the burrs, and if they ever saw any heat treat it was while rolling past an oven on a cart. Compared to my Te-Co's? Well there isn't any. It was cheaper than I could have bought the bar stock to make my own set. But had I known before buying just how soft they were I still would have made my own unhardened set.