Need Help!- How tight should a QTCP lock?

[TroyO]

I just got my first lathe, a HF 8x12 (8x14) but without ever having used one before, I had a couple of questions.

First... I got the A2Z CNC QCTP from LittleMachineShop, and have been having problems with it.

How tight should the post hold the tool holders? I can easily swing the locking bar past the locked position and through to the other side of the cam action.... is that right? It just doesn't feel like a solid lock at all. I was expecting it to take a "firm tug". (IE... not monkeying it but more than I'd like to do using my pinky.)

I just ran my first couple of cuts and was parting off an aluminium tube and the cutoff tool actually slipped down past the height adjustment nut. It just doesn't seem right. There's over a 1/16 play between the dovetail on the holder and the tool post when it's locked. I'll shoot an email to A2Z as well (They happen to even be in my hood) but I'd imagine they are out for the weekend and I want to play NOW... LOL.

Next inane question, ... the compund is a bit tight to turn and it feels like the screw shaft may be off center. I took it apart, lubed everything and even lapped the gib and it made no difference. I'm thinking that the part of the screw that rides in the hole on the compound (Kind of like the shaft that would go in a bushing.) is out of true just a touch. It's tight at the same place in each rotation. Does that sound like a resonable diagnosis? If I get that part (and check it for true) it should be better?

<--- That guy is just there because I like him.

[Al_The_Man]

Originally Posted by TroyO How tight should the post hold the tool holders? I can easily swing the locking bar past the locked position and through to the other side of the cam action.... is that right? It just doesn't feel like a solid lock at all. I was expecting it to take a "firm tug". (IE... not monkeying it but more than I'd like to do using my pinky.)

That does not sound right, you should be able to turn the locking bar up against a dead stop.
Is this a piston or wedge type?
Al.

[TroyO]

I believe it's the piston tyoe... a cam inside the block pushes plugs out against the bit holder.

I can get it to work a little better by shimming a piece of thick card stock between the piston and the bit holder, but that's obviously not the right thing to do, LOL.

[Al_The_Man]

Sounds like one fell through the QC cracks!
Al.

[TroyO]

Thanks... I figured it wasn't supposed to be that way. I'm new to metal machining and such but have made a lot of "stuff" from various materials. The QCTP just didn't seem up to the task.

I just didn't want to jump the gun and go for a replacement to find out I was just inexperienced and that was how it was supposed to be.

[fretsman]

You're not jumping the gun at all.

That should lock up tight for you as I have one as well and I'd snap the handle off before it turned a full rotation -

Dave

[TroyO]

I'm fortunate enough to live in the area of A2Z, and stopped by to have them take a look.

They replaced the body and the pistons for me, no problem. He explained that there was a problem with some they didn't catch. The anodizer they used had to re-do some and the stripping process had left some slightly undersized.

They have a piston kit that resolves the issue, and in my case since I had trouble with the cutoff tool holder sliding down past the depth stop they replaced that as well.

They took care of it right away, and even took the time to check every tool holder I brought for fit and made sure they all worked properly.

All in all, -1 for having a problem in the first place but +5 for resolving it without a hassle and even going the step beyond to double check everything else.

Thanks all for validating my concerns and steering me in the right direction!

[digitalmdj]

I have a A2Z also and the tool holders are a sloppy fit. This should not happen for the price they charge for the tool post.

[DonF]

If you look back through the posts of people who used a A2Z tool post on the 8x12 there is alot of complaints. Flex in particular. Lots of good reviews of the lathemaster one http://www.lathemaster.com/QUICK%20C...POST%20SET.htm Me I'm still using the stock toolpost with homemade shims just because its not that slow once you have a set of shims made up and the stock tool post is strong! It also has the locator spring/ divet that holds it in place, something you loose when you go to a QCTP.

[digitalmdj]

It is way over priced for what you get.

[DonF]

I called A2z about a year ago, they are very up front about thier QCTP. The owner said with 1/2" tooling the tool post will flex more than the tool. So that was that. I read here that the A2Z was great for a 7" and under lathe probably so...

[digitalmdj]

If they would just machine it properly half their problems will go away. But bottom line seems to be the whole issue here making money.