How do YOU make a "T" nut for your QCTP?

[HMF]

You buy a new QCTP and it comes with an oversize "T" nut that you have to mill to size.

How do you do it? (Photos if possible). How do you measure the correct dimensions of the T-slots, set up the job on the milling machine or other machine that you use, and remove the excess material.

This is an important task for newbies.

Thanks,


Nelson

 

[aametalmaster]

Re: How do YOU make a

I know how i made your tee nuts with my shaper...Bob

 

[pdentrem]

I used hack saw to rough out the nut and then set it up in my milling attachment to finish the nut. The first one I used the saw method but finished by file as I did not have the milling attachment at that time.
For my new set of Phase II, I am making a new top slide for the compound and will just drill and tap a hole for the tool post bolt. I hope to finish it this week.

 

[PurpLev]

Re: How do YOU make a "T" nut for your QCTP?

I measured t slot dimensions with a caliper, cut out a rough block of steel, and using a milling machine squared and dimensioned the part to size, and milled out the T rabbets:



Sorry I don't have any in-process photos, but these were basic milling steps - squaring and dimensioning a part, and milling a step at a certain depth from a (dialed in) edge.

If you are looking for some basic milling tutorials/lessons/whatnot I highly highly recommend Darrell Holland videos on lathe work and milling:

http://smartflix.com/store/author/75/Darrell-Holland

very very well made.

 

[AR1911]

Re: How do YOU make a "T" nut for your QCTP?

Well, I didn't know enough to do it properly. All I had was a 9" lathe

First I measured the compound to determine the dimensions, and marked the areas to be removed on the supplied t-nut blank.
I chucked that blank endwise into the 4-jaw and faced it down to the correct width.
I installed the QCTP stud in the blank, then chucked it in the 3-jaw. I faced of off down to the correct thickness. Length was OK. Now I had a blank that was correct thickness, length, and width, just needed the steps milled.

I made a round t-nut in the lathe to fit my topslide. Sort of a stepped washer/nut, tapped in the center for the TP stud.
This let me temporarily mount my new QC post. I probably could have used this indefinitely, but it does not spread the load across the casting as it should.
Then mounted the blank that came with the QCTP into one of the toolholders, using it as a milling vise.
I chucked a 1/2 endmill into the 3-jaw chuck (Bad idea, collet is best).
I adjusted the height to get the cutter where it needed to be, then milled off the shoulders to the correct dimensions.

Replaced the round t-nut with the newer version.
This works OK because the tolerances are very loose.

 

[xalky]

Re: How do YOU make a "T" nut for your QCTP?

I used hack saw to rough out the nut and then set it up in my milling attachment to finish the nut. The first one I used the saw method but finished by file as I did not have the milling attachment at that time.
For my new set of Phase II, I am making a new top slide for the compound and will just drill and tap a hole for the tool post bolt. I hope to finish it this week.

I didn't have my mill when I cut mine to size. I did it in a similar fashion to you. I rough cut it close on my band saw and hand filed it. It doesn't have to a dead-on fit but I got it pretty darn close by hand with a file. It's a real simple job on a Bridgeport. Sorry, no photos either.

 

[Benji]

Re: How do YOU make a "T" nut for your QCTP?

You really do not need anything more than a lathe.
First rough cut to size. I used a horizontal band saw but a hack saw and a lot of sweat would work.



Then chuck the OVERSIZE part in your lathe with a 4-jaw and finish both sides. Make the width 0.010 undersize and center the edges on the tapped hole.



Now break the corners. Remove any buildup.
Next I screwed the blank onto the shaft it came with and chucked it up in a 3 jaw chuck. I turned a stub the width of the compound slot less 0.010.



Doing it this way insures the boss is concentric with the screw shaft and the top flat is at right angle to the Boss. Again allow 0.010 in the thickness.

Break the top corners to allow clearence from and radius in the corners of the compound tee slot.

This was for an Atlas 10" lathe and here is how it fits.

 

[ScrapMetal]

Re: How do YOU make a "T" nut for your QCTP?

I also used the method that Benji did, with the exception that I used a 4-jaw chuck without the bolt/shaft and mine was for a SB.



Trimming to width




Using a 1-2-3 block to space it in the chuck and a combination of two jaws and live center to hold it in position.



Almost finished.




Fitting it to the compound.

-Ron

 

[xalky]

Re: How do YOU make a "T" nut for your QCTP?

Thats another way to do it. You guys making stuff on your lathes that I never thought possible. :thinking:

 

[Hawkeye]

Re: How do YOU make a "T" nut for your QCTP?

Okay. I guess I have to put in a little tool gloat here. I never expected to have a mill that could do this.


Those are 6" diameter cutters on a 1 1/4" shaft. The hubs on the cutters are flush with the edges of the teeth, so the thickness of the shims equals the space between the cutters.


With the right setup, one pass completes the profile. Feel the power!