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Old 05-01-2015, 11:16 PM   #41
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Its 24mm. Do you think there is enough room inside the QCTP for this to be bored out ? I don't suppose you can take a picture of the bottom of your QCTP so I could see what it looks like ? Or take it apart to see what room might be inside for a 24mm hole ? That would be a great help if you can ?

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Old 05-02-2015, 12:10 PM   #42
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Its 24mm. Do you think there is enough room inside the QCTP for this to be bored out ? I don't suppose you can take a picture of the bottom of your QCTP so I could see what it looks like ? Or take it apart to see what room might be inside for a 24mm hole ? That would be a great help if you can ?

Cheers.
I think you could get away with it. Here is the base and it has a 25mm or so threaded hole.



This screws in from a slotted top on the top side


I think you could shorten the treaded post but I did not dissassemnle anything to check. I have had it apart before and it is tricky to put back together but it is doable.


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Old 05-02-2015, 05:52 PM   #43
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Timoxx4 - Found a picture (attachment) of my AXA type 100 which shows what is inside. Basically there is a central tube that holds the QCTP together. The bore in mine is 14mm but the larger BXA type 200 has a bore of 16mm. The tube isn't that thick so I doubt if you could machine it out to 24mm. If you want to take yours apart the end of the tube is a left hand thread.

I had a similar problem on my Warco WM250 (UK) and ended up machining the boss. You can see details on my site - Fitting a QCTP

Good luck
John
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Old 05-02-2015, 09:51 PM   #44
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Timoxx4 - Found a picture (attachment) of my AXA type 100 which shows what is inside. Basically there is a central tube that holds the QCTP together. The bore in mine is 14mm but the larger BXA type 200 has a bore of 16mm. The tube isn't that thick so I doubt if you could machine it out to 24mm. If you want to take yours apart the end of the tube is a left hand thread.

I had a similar problem on my Warco WM250 (UK) and ended up machining the boss. You can see details on my site - Fitting a QCTP

Good luck
John
That is actually quite different to the mechanism in mine. With mine turning the slotted head withdrew the centre shaft from a thread at the bottom So the column is a single part.
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Old 05-03-2015, 12:13 AM   #45
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Thanks for the pictures. That helps a lot.

Hmm looks like I might have to cut my boss down I think. If I bored out the bottom hole on the QCTP it would pretty much wipe out that entire threaded portion on the bottom.

Only problem now is I need a tool post in the lathe to machine down the boss but cant because the piece with the boss on it will be in the lathe chuck

Also if I machine the boss down to 16mm to fit inside the QCTP it would be very thin in the walls as the hole in the boss where the original bolt sticks out of is 14mm. So the cast boss would only have 1mm thick walls left ?

I am not real sure what to do now? I didn't want to remove the boss completely as I think it would add a lot of support to the tool post. And I would also like the option of being able to go back to the original tool post if need bee.

Any ideas ?
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Old 05-03-2015, 08:33 AM   #46
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That is actually quite different to the mechanism in mine. With mine turning the slotted head withdrew the centre shaft from a thread at the bottom So the column is a single part.
It should be the same I think. The two pieces might just have been stuck together when they came out but the slotted head piece should turn inside the scroll piece so must be 2 pieces or it wouldent work.
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Old 05-03-2015, 08:57 AM   #47
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Timoxx4 said - "Only problem now is I need a tool post in the lathe to machine down the boss but cant because the piece with the boss on it will be in the lathe chuck "

Yes that's exactly the problem I had and I ended up making a new tool post that fitted directly to the cross-slide. I also ended up with a very thin boss 14mm dia with an M12 thread down the middle but more by luck than judgement the cast iron didn't crack. You are right about the slotted head piece it goes down the centre of the actuating mechanism which rotates around it, as you say it wouldn't work if it was all one bit. The thread or ramp that makes it work is a three start left hand acme thread that pushes the wedges down to clamp the tool holders.

The boss on your lathe doesn't look as high as mine was perhaps you could make a really thick washer about 60mm dia to fit over the boss and fit the QCTP on top of that if the vertical height allows the tool to come down to centre height!

John
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Old 05-03-2015, 08:34 PM   #48
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I think timoxx4 was right and I was wrong. Mine is the same.

The other alternative is to look at the reccommended tool post for this lathe.
http://www.machineryhouse.com.au/L295

It is a very good bit of gear and I think from memory it already has a recess cut into the base. Shame about the price!

I think if you made a spacer so the tool post sat above the boss it would be too high for most tooling.

I've got 1 or 2 16mm tools and they just fit in at centre height, mostly I use 12mm.
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Old 05-03-2015, 11:36 PM   #49
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Wow, yeah $500+ is a bit out of my range for a tool post. Looks like it would fit straight on though. Tool holders are a bit pricy also for it.

Yeah I try to use all 12mm tooling with my lathe also. It would be interesting to see if they might sell just the cross slide part for this machine and I could have one to machine all I like and not worry about ?
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Old 05-04-2015, 11:25 PM   #50
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They will sell parts as a mate bought a spindle so he could build a CNC lathe.

The otber alternative would be to make your own crossslide. I've thought about that a couple of times. I'd probably use Cast Iron which you can get from George Weston. They cut to size.


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