[Newbie] Dose QCTP holder length matter?

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axa88

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I have a BXA sized QCTP and the set come with I suppose is the standard length 250-200 and 250-201. I'm going to buy a dozen or so additional holders, but I finding them in a shorter length for the BXA post. Roughly 3 inches as opposed to standard 4 or so, I forget the specific. All the other dimensions are the same.

So my question is does the length of the holder have any burden on use?

The only things I can think of is:

1 longer sort of additional support for tool stick out? Or does shorter have better rigidity?

2 longer additional support for long tool bit clamping? Or this end of the tool doesn't really matter?

3 longer the ability to hold another tool on the other end. Or is this hardly an advantage cuz #2 or it gets in the way. Can't be centered perfectly on both sides?

4 none of really this matters, get whatever

Please advise to help me select new holders thanks.
 
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I vote # 4 . Sometimes you feel like a nut , sometimes you don't . OK , bad joke . Sometimes the extra length is needed to support a weaker tool .
 
mmcmdl said:
I vote # 4 . Sometimes you feel like a nut , sometimes you don't . OK , bad joke . Sometimes the extra length is needed to support a weaker tool .
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So actually your voting #1 longer and 4..:drunk:
 
So mounting indexable tools on both sides of the holder not very popular?
 
axa88 said:
So mounting indexable tools on both sides of the holder not very popular?
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Most Aloris tool posts hold tools on the left side or the back of the tool posts. You would have to rotate the tool post to do left hand turning.
 
Illinoyance said:
Most Aloris tool posts hold tools on the left side or the back of the tool posts. You would have to rotate the tool post to do left hand turning.
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Well if I have a left hand tool, I wouldn't put it on a holder having a right hand tool as well. But why not rotate the post a bit and do some facing with the same holder on the back mount, or use the back mount with a chamfer/debur tool.

Sorry for the stupid questions but they are genuine
 
mmcmdl said:
You can . Turning and facing tool . You can also use one tool for both if the grind or insert is right though .
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Let's be real here, I can't grind my tools well let alone at the exact same height :(
 
If you can't or won't grind HSS tools I suggest buying LH and RH tool holders that take CCMT or CCGX inserts. They have the proper end ans side relief for turning or facing without re-orienting the toolpost. Some favor style D inserts. They work for turning or facing as well. Style C inserts are an 80* diamond. Style D inserts are a 55* diamond.

As an aside, in the 50s we were not allowed to run the lathe until we had ground our own tools.

Re: post #5. With most Aloris holders the side and back tool positions are not used simultaneously. Aloris does make an indexable tool post that can mount 4 tool holders. That toolpost requires different tool holders than the standard toolpost.

Re: post #9. Aloris style tool holders are adjustabe for height. There is no need grind tool bits to the same height of cuttting edge. That assumes each individual tool has its dedicated holder. I know of hobby machinists have 24 or more holders. I think 5 or 6 is plenty.
 
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