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Home > Shop Tips > Adding a Quick Change Tool Post (QCTP) to a Grizzly G0602 10×22 Lathe

Adding a Quick Change Tool Post (QCTP) to a Grizzly G0602 10×22 Lathe

My first modification after buying my G0602 was to add a Quick Change Tool Post. QCTP’s have many advantages, including quick and easy tool changes, consistant tool height setting, and safety (sharp tools sticking out in 4 directions from a standard 4-way tool post can be a painful way to learn a lesson!).

Anyway, adding a QCTP to the G0602 is very simple, as long as you  access to a milling machine to mill the plate that fits in the t-slot. Here’s a video of the process.

If you don’t have a milling machine you could figure out a way to hold the plate in your 4-way tool post and use an end mill held in the chuck (or better yet held in an end mill holder that fits the taper of your lathe spindle). But you’re best bet is to use a mill to modify the plate to fit your t-slot.

One final thing, your QCTP probably came with a plate to modify as mine did. But my plate was a bit short, so I fabricated my own out of a piece of scrap. Doing so requires you to also have a proper tap handy. That tap size may vary depending on who made your QCTP, but just keep that in mind if you decide to make your own plate rather than modify the one the tool post comes with. I purchased my tap for about $12 from a local supplier (no shipping). You could probably get one for about the same price from an online supplier + shipping. If it’s a size you think you’ll use a lot moving forward, go ahead and purchase a high-quality tap. But if not, go with a cheap tap. I haven’t used my tap since adding the QCTP over two years ago, so the cheapest tap they made was perfect!

As an alternative to buying a tap, you could also single point the internal threads on the plate, but that’s a whole ‘nother ball of wax, and somewhat outside of the scope of a beginner-level modification. But if someone does single point their plate, please post a comment with pictures &/or video of your modification.

 

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About Tyler

Tyler is a hobby machinist and 3D printing aficionado. He teaches computer programming and web development at Highline near Seattle. Tyler founded Projects In Metal in 2008 because he was frustrated by the lack of free plans available for hobby machinists.

23 comments

  1. Gratz on the new QCTP!

    I don’t use the old set screws. They just scar up the slot. I think they were for making sure that your 4-way didn’t move around, but they seemed pretty useless (and even damaging) to me, so I didn’t tap my new QCTP plate for them.

  2. Tyler,

    Thanks for the info on the set screws.

    My cross slide has a pin which has a 45 degree end on it, but the bottom of my QCTP (from CDCO) has a corresponding hole on the wrong side, so I just removed the pin and the spring that was underneath it. Should I be worried about this?

    Since I had been taking CNC courses lately, it had been awhile since I had been in the manual machining class.  My 3/8″ HSS lathe tool that I had ground in the first couple of days had been with me over several manual machining classes, but it went missing (stolen by the night class !) one day near the end of the term.  The instructor only had 5/8″ HSS tool blanks, so I went to town on grinding a lathe tool.  Holy cow, but a 5/8″ HSS tool is a LOT bigger than the 3/8″ HSS tools I was used to.  There had to be at least 6 times the amount of metal that needed to be ground away.  The resulting lathe tool was too large to get on center on the BXA QCTP on the school lathes, so I ground the bottom down to 1/2″ on the Blanchard grinder.

    Fast forward to last week when I finished up my QCTP and was ready to cut the first chips on my G0602.  I inserted the 5/8″ lathe tool, but it ended up being around 1/16″ too high to get on center.  I was faced with two choices: 1) grind a new tool bit from the 3/8″ HSS tool blanks that I now have, or 2) mill down the bottom of the QCTP holder with my G0704 mill.  Actually there was a third choice.Embarassed  I decided to cut my first chips with that massive 5/8″ tool bit knowing that it wasn’t on center, and that the finish wouldn’t be the greatest, and that it would not be healthy for the tool bit.

    I started out with 0.010″ cut on the cross slide and it didn’t slow the machine down one bit.  I graduated up to 0.025″, and then 0.040″.  Ditto on the machine not sweating over the cut.  On to 0.050″. No problemo.  Just to be a masochist, I then let the lathe do 0.080″.  The chips started coming out straw colored, and I knew that I should stop abusing the lathe and HSS tool bit.  Then is when I got quite a shock – I measured the difference in diameters just cut and I came up with 0.160″!!?!.  It turns out that the G0602 cross slide is calibrated for actual cross slide travel instead of the more common (at least on the school lathes) practice of the cross slide being calibrated for diameter.  My little toy lathe just cut 0.160″ diameter?!?  What a little beast the G0602 is!  Now I grant that I didn’t cut 0.160″ for more than a 1/2″ to 3/4″, and it boogered up the tip of my lathe tool a little, but still I am very, very impressed.

    So to solve my problem of not having a proper lathe tool bit, I then decided to go with option 2 and cut the bottom of one of the QCTP holders on my G0704 mill.  To my surprise, the CDCO QCTP holder was exceedingly hard and I ended up ruining one of my 5/8″ HSS endmill trying to mill the bottom.  Perhaps carbide tooling would cut the QCTP holder, but I don’t yet have any carbide in my tool arsenal.

    So I ended up finally going with option 1 and grinding up a new 3/8″ HSS tool bit from scratch like I should have done in the beginning.  The surface finish on the cut ended up being much nicer, but still nothing to write home about.  The 1″ diameter steel rod I was cutting is one I had bought from a scrap yard, so I really don’t know what mild steel alloy I was faced with.  Later I had to make a bushing spacer for my HF 4×6 bandsaw, and the surface finish on the rigid steel conduit that I used for raw stock had a much nicer finish.

    I love my QCTP!!

    Titaniumboy

  3. I had the same pin and spring. I can’t remember exactly what it was for, but I think my 4-way had notched in the bottom of it at about 15 degree intervals. So the pin probably served as some sort of (useless?) stop. I removed the pin and spring and have not missed it.

    1/2″ is about the largest tooling you can use with the G0602 because anything larger (as you’ve noticed) will be too tall to get on centerline.

    About the straw-colored chips. If the lathe wasn’t laboring there’s nothing wrong with your chips changing color. If the lathe can handle it than feel free. For me thicker chips seem to pull the heat away with them (rather than the heat staying in the part) and they seem to break more readily so that I don’t get long stringy chips. So my chips are often discolored.

    I think the most I’ve cut so far was about .050 (so .100 dia) in cast iron. With the diamond tool holder it was easy to do. But I think with a traditional HSS tool I wouldn’t have attempted it.

    I usually don’t try to take too aggressive of a cut, however, because I’m typically not in a hurry.

    Oh, and your tool holders are hardened so yea, they’ll be very difficult to mill unless you were to anneal them. Buying smaller HSS blanks is a better idea. :)