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browne92
03-24-2014, 10:03 AM
I plan on building one, assuming I don't get rich enough to buy what I want first (not likely).

My understanding of the QCTP system is to have one post and many holders. I would also think that once a holder got loaded with a left hand tool, it would pretty much stay with a left hand tool, same for the right. Is there any reason that my under-coffeyed brain can't fathom that I couldn't save myself a milling and two drilling/tapping operations (and the associated broken taps) by making holders either left or right handed?

Also, am I correct in thinking that the vertical hole close to the post houses some sort of height adjusting set screw?

http://img.photobucket.com/albums/v55/EPAIII/Milling16aRnR.jpg

Thanks.

Bill

burdickjp
03-24-2014, 10:54 AM
They look rather symmetrical. You may be able to flip them over as well, and not need handed holders at all.

dalee100
03-24-2014, 11:04 AM
Hi

The holders are actually not handed. That is determined by the tool. It just appears that way from the way the tool post is sitting in the photo.

Rotate the post 90 and it will be apparent.

Dalee

vpt
03-24-2014, 11:11 AM
Yes normally once you set up a toll in the holder it stays there. However you will probably never have enough holders to do that with every tool so there will always be that one holder that you still change tools out on. At least that is how it is for me. I have the most used tools set up in most of my holders but then have a couple of holders I use and change out the tool in all the time. Because there will always be that certain grind you need for an operation.

I need to make more holders. lol

jlevie
03-24-2014, 11:48 AM
In an ideal world you'd have a holder for every tool. In the real world, even in commercial settings, the number of holders is limited and tool changes will occur. It is nice to have enough holders, preset set with tooling, for the most commonly used tools. That might be no more than right and left hand turning, chamfer, cutoff, threading, and boring bar tools. Then it is nice to have one more holder for odd, seldom used tools.

But it isn't a big deal to change the tool in a holder, just takes a few minutes.

Jaakko Fagerlund
03-24-2014, 01:11 PM
In an ideal world you'd have a holder for every tool. In the real world, even in commercial settings, the number of holders is limited and tool changes will occur. It is nice to have enough holders, preset set with tooling, for the most commonly used tools. That might be no more than right and left hand turning, chamfer, cutoff, threading, and boring bar tools. Then it is nice to have one more holder for odd, seldom used tools.
But it isn't a big deal to change the tool in a holder, just takes a few minutes.
Yup, a sound from a tool & die shop here. We do have enough holders for all the tools and then some, but the problem is that there is not enough tools. Having a situation so that you would not need to move a tool in its holder or change something else would require plenty of the same tools, as for example I might be boring something that is 10 mm deep and I want a heavy cut, so the tool hangout is minimal and the next thing I know I'm boring something 200 mm deep with the same tool, so I have to reorganise things. But yeah, a matter of minutes work.

I've been thinking of doing that sort of tool holder at work for one lathe, would be handy and the ease of doing extra holders would be nice. Though I would make the whole thing case hardened and ground, so it would be durable in daily use.

Paul Alciatore
03-24-2014, 02:37 PM
I plan on building one, assuming I don't get rich enough to buy what I want first (not likely).

My understanding of the QCTP system is to have one post and many holders. I would also think that once a holder got loaded with a left hand tool, it would pretty much stay with a left hand tool, same for the right. Is there any reason that my under-coffeyed brain can't fathom that I couldn't save myself a milling and two drilling/tapping operations (and the associated broken taps) by making holders either left or right handed?

Also, am I correct in thinking that the vertical hole close to the post houses some sort of height adjusting set screw?

http://img.photobucket.com/albums/v55/EPAIII/Milling16aRnR.jpg

Thanks.

Bill

Bill,

There is no reason why you can not make holders with just one tool slot. As for broken taps, you could use an easy cutting steel, perhaps a leaded one. I use a small tap alignment block to start the taps and I have not broken a single tap since I made it. I think starting a tap crooked is one of the biggest causes of broken taps.

On the height adjustment, yes that hole does contain a SHCS for height adjustment. Instead of using the standard locking nut, which can disturb the adjustment you are trying to lock, I used some fishing line in the hole before inserting the screw. It locks the screw, much like the nylon inserts, but you can easily adjust it at any time. This has proven to be very reliable in use. Only drawback that I can see is you have to replace the fishing line if you remove the screw for any reason. But fishing line is dirt cheap and I keep a couple of rolls in the shop at all times as it is handy for other things.

Although, thanks to my use of the adjustable clamp screw, the tool holders can be changed without any tools, I did include a multi-tool for setup use in the article. It has three tips, two Allen and one socket. It is all you need to install tools in the holders and adjust them for use. It also has the socket for installing the post.

I was a after a way to make an acceptable QC holder in my shop, using the fastest and simplest methods possible. At the time I had not made any dovetails so I wanted to avoid that. (I have since found them to be fairly easy, but that is another story.) And I wanted the best accuracy when tools were interchanged. I liked the round post design for ease of construction and rigidity, but after some research I rejected the more common idea of using some kind of key. I felt that the keyways on a round post would have too much slop and lead to variations of the tool's tip on successive mountings. This could be partially offset by technique, but I felt it invited problems. So I settled on the "D" post design and it has proved to be very accurate. Overall, I have been surprised by the combination of good features of this design and feel it has more than met my original design objectives.

If you build it, please post the results for all to see.

Void
03-24-2014, 02:38 PM
Bill if you are worried about breaking what look like 1/4-20 taps then you should worry more about your tapping skills and tools and less about the number of holes. First: Buy a couple of good quality taps. Since you are tapping through holes get a gun (aka spiral point) tap. NOT spiral flute taps. NOT hardware store plug taps. Use tapping oil (TapMagic or whatever.) Drill the correct size holes (so get a couple of drills that are the correct size.) If you have a problem guiding the tap... just tap each hole immediately after drilling on the drill press. Just swap in a guide point or cup for your style of tap/tap wrench.

You should also consider making one of the other styles. Either a copy of the Aloris (and clone their tool holders) or one like Stephen Thomases design (somewhere up thread.)

-DU-

Paul Alciatore
03-24-2014, 02:40 PM
One more thing. It is not obvious in the photos, but the holders are not completely symmetrical. One of the flats for the clamp is about 0.010" lower then the other to allow for good clamping action.

JoeLee
03-24-2014, 03:00 PM
I would like to see the tool post and how you are going to lock the holders down.

JL.......................

Void
03-24-2014, 03:38 PM
JL,

Previous thread with more pics and discussion is here: http://bbs.homeshopmachinist.net/threads/58524-QCTP-More-rigid-design

-DU-

browne92
03-24-2014, 05:05 PM
If you build it, please post the results for all to see.

Thanks Paul. I will.

The "tap" remark was actually sort of joke. Guess I should have used a smiley. :p

JoeLee
03-24-2014, 06:52 PM
JL,

Previous thread with more pics and discussion is here: http://bbs.homeshopmachinist.net/threads/58524-QCTP-More-rigid-design

-DU-OK, that's better, I thought I was missing something.

JL...............

Paul Alciatore
03-24-2014, 11:17 PM
May as well add the tool porn here too.

http://img.photobucket.com/albums/v55/EPAIII/QConSBLathe.jpg (http://smg.photobucket.com/user/EPAIII/media/QConSBLathe.jpg.html)

This shows that it can be used close to the tailstock center.
http://img.photobucket.com/albums/v55/EPAIII/BytailStock.jpg (http://smg.photobucket.com/user/EPAIII/media/BytailStock.jpg.html)

You can see the height adjust screw protruding out the bottom of a holder here:
http://img.photobucket.com/albums/v55/EPAIII/Disassembled.jpg (http://smg.photobucket.com/user/EPAIII/media/Disassembled.jpg.html)

http://img.photobucket.com/albums/v55/EPAIII/Milling16aRnR.jpg (http://smg.photobucket.com/user/EPAIII/media/Milling16aRnR.jpg.html)


I would like to see the tool post and how you are going to lock the holders down.

JL.......................