T-slot Bolts For Milling Machine
The specifications for my mill call for 1/2' T-slots, and the vise that came with it uses T-bolts. I have a couple of stainless steel T-nuts that seem to be for 0.562' slots, and they are 0.63' H x 0.88' W with a 0.34' H slot section. I milled one of them down to fit, and it is now 0.570' H x 0.656' W with a 0.29' slot section:I have a couple of step clamps and some clamping bolts with 1/2'-13 threads that fit these T-nuts. But I would like to get a set of clamps for the mill, and I found one that should work, which uses 3/8'-16 threads and is designed for a 7/16' T-slot. The T-nuts are 0.50' H x 0.688' W with a 0.219' slot section. Since the width of the T in my table is about 0.656' W, I would need to mill about 0.015' off each edge, and they should work.
Here is the set I'm thinking about, for around $55 with shipping:But for $65 I can get a set for 1/2'-13 bolts designed for a 5/8' slot and I could mill the T-nuts to fit as I did with the ones I have.And for $68 I can get a set for 1/2' slots, with 3/8'-16 bolts, and the T-nuts are 0.88'W x 0.50'H with 0.28' slot section. So I would need to mill off 0.112' from each edge.Another company seems to have this same set for $52 including shipping:And they have the 5/8' slot set for $55:I don't know if the 1/2' bolts and possibly larger clamps will offer much improved holding strength, especially if the T-nuts are milled so close to the threads that they are exposed on the edges, but I could also possibly get a T-slot cutter and open up the slots to fit the larger clamps. However, I'm not really feeling too good about doing that, even though it seems that the slots are non-standard.Another consideration is if I would get a larger milling machine it would have larger slots, like the Grizzly G3103 with 0.56' slots.
But I haven't seen clamping kits for 9/16' slots, at least not from these sources.Well, there is this one, but it's almost $90 with shipping:Any suggestions? Three thoughts:seems like a lot of extra work, having to mill a bunch of 'T' nuts.any chance the slots are metric? And if you end up having to mill them all anyway, why not just make your own from scratch?thought these types of things were hardened (not saying they could not be milled but.)9/16' could be one of those dealies where most mfg make them but 'rare' enough that they don't sell them as sets (found the same thing with table slot size of Atlas horizontal.and found out later one or two makers do make them as sets, sort of, not the complete sets you often see but two 'add on sets' together.on sale the bits and pieces can be cheaper than full sets). Yes, do not mod the table T slots.Does Metric stuff fit?
It might be 14MM slots designed for slot nuts intended for 12MM studs. The slot width is the controlling dimension. Most likely they are proportioned for Metric T nuts. The 1/2' figure probably came from some genius marketer thinking 1/2' is pretty close to 12MM and if promoted as such will probably sell more machines in inch-based US.I looked but may have missed it: what is the actual measured width of your machine's T-slots?Do you have an aversion to using Metric T-slot hardware? 3/8' T slot equipment provides plenty of hold down force for most work and the T nuts will work without modification.You are going to find most T nuts are hardened. No biggie but you will have to draw them back to machinability, accomplish the mod, then re-harden (should be a simple heat to red, quench, and draw to 500 degrees in a toaster oven. Even if you machine the case away in places, your mods should have little efect on the wearing qualities of the tapped threads and the part of the step that abutts the underside of the T slot.
T Slot Bolts For Drill Press
Shoot for 1/64' to 1/32' clearance. Any more would allow chips to jam slot-nut movement and less invites sticky movement.Over the coming years, you will probably make a dozen or so oddball T-slot nuts for different jobs Now is a good time to make a few 6' pieces of blank slot-nut stock to keep on hand. Later, as needed, you can cut them to length, drill and tap.Last edited by Forrest Addy; at 12:17 PM. I had a similar problem with my Griz mill that advertised 1/2' slots. This really refers to the stud size in the clamping kit.
The Tee nuts and table slots are really a fair amount larger than this - 1/8' to 1/4' larger. I bought a 1/2' clamp set and the Tee nuts did not fit.Places like Enco have Tee nuts in a variety of sizes and I just measured the slots and bought a size that fits. I got extras for future needs.For your table I would defenitely not use the 1/2' stud size. 3/8' is common and, from your photo, is probably the size intended for your table. That would allow about 1/16' of meat on each side of the stud.
Milling Machine T Slot Covers
These cheapo clamping sets I bought (one E-Bay and one from Enco) seemed like a real bargain and indeed I have bragged about mine in the past but not so much anymore! While the clamps and studs/nuts may be ok the step blocks have been a problem, it seems the teeth have an annoying habit of crumbling! This was solved by replacing them with the 'Gibraltar' brand from Enco along with a few other 'Gibraltar' components such as nuts and T-nuts, the difference in quality and strength is noteworthy to say the least! I have since decided that spending the extra money for the better set at the outset would have been a much better decision, certainly the cheapo sets work but believe it or not the 'better' sets are indeed MUCH better and well worth the extra cost. My T-slots appear to be close to the 12mm metric dimensions, except the base is about 16.5 mm rather than 19 mm:The true metric clamping kits are almost $200 from Enco, and that's out of my comfort zone.
I haven't really even needed such clamps so far, although I may in the future and I want to have what I need on hand. They have an import set for $60 (free shipping):Another consideration I just thought of, is that my 6' rotary table also has T-slots. I just measured them, and the slots are 0.398' wide, with 0.78' wide base having 0.350' height, for a total depth of 0.756'. I will probably need clamps for that more urgently than the milling table. Need for speed most wanted mods jtag.
So that is a standard 3/8' slot, and the Gibralter from Enco is about $162:An import set from an eBay supplier is about $50 with shipping:So maybe I can use the two T-nuts I have that I can modify to fit the milling machine table using 1/2' bolts and the 1/2' step blocks I have, which may meet most of my needs, and perhaps I can make some T-nuts with 5/16' threads so that I can use the clamping kit designed for 3/8' slots. This will give me more versatility, although the 5/16' bolts will not be as strong as the 3/8', or the 1/2'.Another idea I had is the possibility of using T-nuts for the jaw slots of a lathe chuck. I don't know if they are standard size, and it may be better to use the faceplate instead, but is this a viable option?Thanks.