Tee nut standards

[deverett]

About 9 months ago, I bought some M10 Tee nuts for my German milling machine from a well respected UK on-line supplier. They fitted perfectly, and at the price it was not worth making my own.

Fast forward to a couple of weeks ago and I ordered some more to make my latest order worthwhile. Blow me down, the new batch of M10 Tee nuts were a different size! The supplier didn't realise the size had changed when I contacted him. Fortunately, he still had a few of the original size nuts in stock and sent out replacements straight away.

Original size of Tee nuts: 18mm wide, step 6mm high, overall height 14mm
New size: 22mm wide, height of step 6mm, overall height 11m
The stem of the Tee was the same on both batches.

So the question is: Are there different standards of Tee nuts for the same stud thread? In this day and age of standardisation, I would have thought that a slot for an M10 Tee nut (or whatever thread diameter) would be the same regardless of machine manufacturer.

Dave
The Emerald Isle

 

[Maryak]

Maybe M10 v 3/8" ???

Best Regards
Bob

 

[deverett]

No Bob, both are M10 thread.

Dave
The Emerald Isle

 

[Kermit]

An indication of top notch of Hong Kong QC work?

 

[rcmadness]

I have noticed that most large supply catalogues list the actual dimensions of there T nuts and i have seen them vary from manufacture to manufacture. Makes me think there is not "standard" for them.

 

[Stan]

It appears that whoever sells the most of an item gets their standards adopted by others. On older mills the slots seemed to be whatever they decided to make them. Distributors sell T nuts in a wide variety of sizes where you have to check each dimension to match up with your slots.
I had to pay more for 6 T nuts to fit my mill than the entire import clamp set cost, that came with nuts that didn't fit.

 

[Dan Rowe]

The German T nut standard is DIN 508.
http://www.elesa-ganter.com/en/2/sp/7147/4/86/t-nuts/din-508/eg/

Dan

 

[kvom]

I have made my own in several sizes for different slots.

 

[Ned Ludd]

Hi Guys,
I have made many different tee nuts but all with the same size thread. I have many types of device that has Tee slots, mill, rotary table, angle plates, etc but I can use my one set of clamps on all of them. Only one of my toys uses the tee nuts that came with the set. I used bronze for most of my nuts but after nearly 10years there is no sign of distress or rust. Thm:
Ned

 

[cidrontmg]

I did some T-nuts (eccentric work holders, really) for my Quantum BF-16 mill, and measured the needed width from the lateral slots. Both were the same width. When finished, they wouldn´t go to the center slot. Too wide... So much for standards.

 

[deverett]

Interesting to see what others thought.

Fortunately I now have sufficient Tee nuts for my small German machine (Wabeco). But like others, I have some odd-ball size tee slots for other applications and as far as possible, I have standardised on M10 threads which means custom making nuts as required. No hardship, I realise.

Previously I copied the GHT system of work holding, but when I bought the Wabeco I had to change the Tee nut size, hence the move to M10 threads.

Dave
The Emerald Isle

 

[jct842]

One of the first projects for my micro mill was to make some more t-nuts. I picked up some key stock at the hardware store and got cutting. I also threaded them to 1/4-20 and then re-threaded the t-nuts that came with the mill to the same. I also made some clamps out of 1/2" keystock with oval slots milled in them. good practice for a new user to get used to running the mill. john

 

[Tin Falcon]

The machinery handbook has the US standards for T Nuts both for sae and metric threads on the studs.
Tin