Question regarding QCTP for Porper model B lathe

T

takeitdown

Banned
I am changing out the toolpost for a QCTP with the dovetails on the sides. The height from the top of the t nut channel to center is 2.125" , that channel is 1" high off the carriage bed surface. I am looking at AXA sizes and the dovetail height is 2.25" on the dovetail mount. I was told these would work, but I think it's too short. Most of the listings for these refeence swing sizes and lathe model types, but the Porper design is different and there is no crossslide that raises the QCTP holder.

I think I need BXA size which is 2.75" to the top of the side dovetail. The tool holders fit along side this are 1.75" high, the bottom of the tool channel where the 3/8" bit would be is 0.5625 off the bottom, The bit is 3/8" high (0.375" more), for a total height off the bottom of the tool holder attachment of 0.9375. Take that off 2.75" and you get a tool center height of 1.812" with the tool holder flush with the top of the tool post center dovetail. The porper center is 2.125" from the top of the T channel so I would just raise up the tool holder attachment 0.313" and I'm dead on.

Sorry for the long explaination above. Someone please check my math and let me know. The AXA toolpost dovetail height is 2.25" and that would give a 1.3125" tool center height with 3/8 bits with the tool holder attachement flush. I would need to go up 0.8125 to reach the 2.125 center height I need and that leaves only 0.9375 of the tool holder attachment on the dovetail.

Thank you for your time and expertise. Below is what I am looking to purchase. Best part it has the 1' boring bar holder I need for a gun drill in the set, not spending another $40 on another piece.

http://www.ebay.com/itm/330525619157?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
 
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I bought the same Shars but the AXA, made a 1.000" riser out of 2" 6061 T6 that I mounted under it.
Everything lined up with enough adjustment to use 3/8" or 1/2" tooling.

Paul
<@>

Edit:

Sorry that was a 1" riser !

My bad!
 
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Tool post answer

Ryan, you are right again. The BXA size listed on ebay didn't have the correct t slot dimensions. In the BXA they are alot bigger, 0.63 high, 2. 25 wide. The height of the "stem" of the T is another 0.354 and the width of the stem is 1.625" so it's not even close for the Porper T channel.

I will builld up the base under the tool by 0.25" and it will work fine.

Thanks again Ryan.
 
Paul (mindseye)

Would you be so kind as to post a photo of your tool post extension. From all the measurements I see an AXA toolpost needs to be raised to 3.125 or 3.25, to be used on a Porper. If not you cant "hang" the tool holder below the top of the dovetail, it would be above it. That defeats the purpose of having a QCTP with set height adjustments for different tools.
 
This is what I use. It was made by A2Z CNC.

qc tool post 1.JPG
 
Thanks Ryan

Thats 2" round stock? About 1.5" high?

Did you replace the center post bolt with a longer one? So it can be lossened and moved? Im buying a similiar QCTP AXA size 2.25" high dovetails. If I raise it an inch I shoulsbe good. The bilt will be too short then, I presume

Thanks to all.
 
Brian,
Ryan's is cleaner but here's my setup with the Shars.

Shars AXA QCTP with 1.000" riser brass insert 5" bolt and Porper T slot nut.


Mounted ready to run.


With 3/8" tool on center, more than enough adjustment to center the tool in the Dovetail.


I know everything needs to be cleaned,
was in the middle of something and stopped to take some quick pic's..

Get it you'll love it, makes life much easier. Adapting is no problem.


Paul
<@>
 
takeitdown said:
Thats 2" round stock? About 1.5" high?

Did you replace the center post bolt with a longer one? So it can be lossened and moved? Im buying a similiar QCTP AXA size 2.25" high dovetails. If I raise it an inch I shoulsbe good. The bilt will be too short then, I presume

Thanks to all.
Click to expand...

Yes, yes, yes, and yes.
 
JoneseyCues said:
Thats smaller not bigger! If you have to make a spacer for an AXA why would you think a post that's 60% as big as an AXA is an option? Wow!
Click to expand...

Well in reading through the posts, the OP was considering a BXA tool holder and then opted for the AXA (which will require a spacer). There are also pics of the A2Z tool holder which is a nice option, which is also a piston design rather than a wedge like the AXA or BXA (which will require a spacer) .

In doing research for my own Porper I'm gonna go for the OXA (which will require a spacer and is also a wedge design (which most QCTP users prefer).

In taking all these things into consideration, I thought I would be nice and share my findings in case other readers may want a QCTP a little smaller in size to the AXA but with a wedge design as I know a lot of readers also "browse" this section looking for ideas for their own equipment.

I wasn't aware me doing this would make you act like a douche. Maybe next time I'll PM my post to you for approval before I post it, on second thought, no I won't I'll just post it in hopes it helps somebody make a more educated choice on a purcgase and in the mean time you can eff off :wink:
 
You're going the wrong direction! Do whatever you'd like to do, the OXA would be the last option, as if every AXA and BXA on the planet were somehow outside of your grasp. While adding a spacer may be an acceptable option for some its not as good of an option as no spacer. If the BXA is the size that doesn't require a spacer, then guess which one should be used..... I'll give ya a hint, its not the OXA or the AXA. Don't listen to a machinist though, it sounds like you have it all figured out. Interesting rationale! This one is too small, I won't buy the bigger one that tooling is readily available for, I'll buy the smaller making the problem even worse.... Like I said, WOW is all that can be said to that bassacwarkds deduction... And, you're not helping anyone by posting ignorant remarks, you're only proving your own ignorance!

I've got a car on a trailer that I need to haul 300 miles. I have a one ton pick-up that will pull the trailer no sweat, it has a trailer brake controller in it, plenty of power, its ready to go. BUT, I also have a corvette sitting next to the truck, it definitely has enough power to pull the trailer, but there's obviously no hitch, no brake controller, I guess I'm going to spend the whole day tomorrow having a hitch and trailer brake controller put on the Vette. Not because I don't want to take the truck, just because I want to make my life more difficult and create problems for myself that I didn't have before.. Seems logical to me!

People like you are the main problem with forums! Anyone can get on and spew their ignorance without prejudice, when all you're doing is screwing yourself so you can feel entitled to your own opinion. An opinion is only an opinion if it makes sense. If its illogical and senseless, then it ceases to be an opinion and becomes nothing more than a bad idea... Welcome to your BAD IDEA
 
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I'm taking it in the direction you intended it to go.

Like I said my post was an option for those seeking one. And if you were so smart you would have recognized that. And THAT is what these forums are for, as well as people trying to help each other, which is what I did.

I would venture to say you probably think using the A2Z QCTP is an illogical idea as well, each lathe requires a different size riser based on the application. Maybe the makers of the A2Z QCTP should have called you and sought out your advice because the body of their tool post is the same dimension whether they use it for a 7x10, 9x20, taig , or sherline lathe. Those people probably aren't machinists and they probably pull loaded car trailers with vette's!! I only hope those that have read this post don't go back and buy something different because what was working for years now is a bad idea and may not be as effective, at least in your opinion.

Being a machinist may help you deduct your reasoning and that's fine. However I think using tool post like an A2Z or OXA on a lathe that is designed for light duty, will be just fine,however I'm not a machinist.

I came prepared to have a battle of wits however it's obvious you came unarmed. In the mean time I'm gonna go back to living in my fantasy world where I think using an OXA toolpost on my Porper will be just fine. While you go back to coming up with analogies that don't pertain to things pertinent in the conversation.
 
kunin35 said:
I'm taking it in the direction you intended it to go.

Like I said my post was an option for those seeking one. And if you were so smart you would have recognized that. And THAT is what these forums are for, as well as people trying to help each other, which is what I did.

I would venture to say you probably think using the A2Z QCTP is an illogical idea as well, each lathe requires a different size riser based on the application. Maybe the makers of the A2Z QCTP should have called you and sought out your advice because the body of their tool post is the same dimension whether they use it for a 7x10, 9x20, taig , or sherline lathe. Those people probably aren't machinists and they probably pull loaded car trailers with vette's!! I only hope those that have read this post don't go back and buy something different because what was working for years now is a bad idea and may not be as effective, at least in your opinion.

Being a machinist may help you deduct your reasoning and that's fine. However I think using tool post like an A2Z or OXA on a lathe that is designed for light duty, will be just fine,however I'm not a machinist.

I came prepared to have a battle of wits however it's obvious you came unarmed. In the mean time I'm gonna go back to living in my fantasy world where I think using an OXA toolpost on my Porper will be just fine. While you go back to coming up with analogies that don't pertain to things pertinent in the conversation.
Click to expand...

You're not actually that much of a moron are you? It has to be an act.. That's the most ridiculous, nonsensical pile of drivel I've read in quite some time. Apparently you're unable to process an analogy. Where did I say using an AXA, OXA or an A2Z is illogical? I said using anything smaller than a BXA is not as good of an option as using the BXA, simple really. WHY IS THAT? Because it's high enough to use without a spacer. Tool posts aren't designed to be used with spacers under them. Will they work like that? Possibly, but from a machining and a correct tool for the job standpoint it makes more sense to use the tool post that is the right height. PERIOD, that's not open for discussion or interpretation. Small lathes require smaller tool posts.. The difference in physical size of an AXA and a BXA is marginal, it won't affect the performance or operation of the Porper whatsoever. If a BXA is the correct height, then an AXA may be acceptable to some if they think a spacer is the best option, but to go smaller, 60% of the size of an AXA is NOT, 100% should not be an option if you want to do things the right way. You either don't care to use proper tools or you just want to argue about semantics. You are wrong, plain and simple, anything smaller than an AXA is too small for that machine. Sure, someone could jury rig a smaller one up to work, or maybe they modified the tool post mount to be higher, but in stock form it needs a taller tool post than an OXA.

You don't seem to understand that newbies come on these threads. If someone like you with little or no machine knowledge comes in here and reads your post and buys an OXA for their Porper, they're going to be in for a rude awakening because of your limited capacity and poor suggestion. I circumvented that from happening.

Go ahead and write more ignorant rants that aren't based in fact. Just know that I'm done talking to you, I've had my fill of idiocy for today! And thanks for the laugh! You, matching wits with me, yet you couldn't understand how a simple analogy applies... Hahaha. #BozoTheCuemaker
 
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Actually I can process an analogy. Yours was just dumb.

I also know that the discussion is about a QCTP that is for a lathe of a specific design, not something you can purchase from an enco catalog or such. So my option as I suggested does apply. If a newbie comes on and is looking for an opinion to a lathe that is specific to what he or she is doing, they will search or ask. If they also see that others are using a A2Z QCTP, they'll need a spacer. If they buy a A2Z QCTP for a 9x20, they need a spacer!!!! If a person buys anything aftermarket for their Porper lathe, It may have to be modified to work!!!!

It was also stated that using a BXA or AXA would require a spacer, why????? because like I said prior. Your dealing with a lathe of a specific design!!!

What I did was offer ANY readers an option, why because there are SEVERAL different choices that can be used for a QCTP on a Porper, all of which will probably require some kind of modification.

Your mom should've done the world a favor and swallowed you because all you offer the world is closed minded ignorance.
 
At ease men

The BXA would even be a smidge too small at 2.75" center height. Rhe T nut for BXA is much bigger in every dinension than the Porper nut. The AXA nut needs to be cut just a little off width and is 0.06" too thick. A 1" riser gets you to 3.25" tool height...the pirper is 3.125" centerheight. Go with AXA size.
 
My center height from the mounting bracket is 2 1/16th. The spacer for my A2Z QCTP is 1 1/4". Here is a good reference chart to show the minimum center height for each QCTP.

http://littlemachineshop.com/info/qctp.php

On a side note, I have seen various tool posts mounted to the Model Bs over the years and I'd have to say that as long as you can get it to mount and achieve the correct center height, there shouldn't be a problem. I was worried about using the spacer because I thought (as did Joe Porper) it would flex when under a load but the guys at A2Z tested it and showed me all the data to ease my mind. I have been using it for years without any issues for my application.

I understand where Jonesey is coming from, especially with his machining background. You want the 'correct' tool for your machine and application.
 
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