Author Topic: Machining an arbor blank  (Read 1361 times)

Offline redhouseluv

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Re: Machining an arbor blank
« Reply #15 on: January 28, 2025, 02:41:17 PM »
That's great advice Wilf, thanks, I would have never thought of that

The lathe is a Warco 290 and I just measured the diameter across the opening and looking online the nearest morse taper is an MT5 as mentioned by Jason above

The lathe was secondhand and came with a lot of stuff, but no headstock centre and looking at the instructions they don't make sense as an MT3 clearly won't fit!
Best regards

Sanjay

Offline crueby

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Re: Machining an arbor blank
« Reply #16 on: January 28, 2025, 02:50:22 PM »
One trick that is good for spindles with a thread on the end/outside, for removing arbors/tools that have an external flange: before putting the arbor on, thread on a nut onto the spindle. To remove the arbor, loosen the drawbar and turn the nut to pop the morse taper loose. Saves tapping on the drawbar and spindle/bearings. May not apply in this case, but a handy trick.
Here is a couple pictures of what I mean. First a picture of my mill spindle, threaded on the outside and morse taper on the inside:

If I use a morse taper arbor alone, removing it would require tapping on the end of the drawbar or prying between the arbor and the spindle, neither of which I like:

and here with a large thin nut threaded on the spindle before installing the arbor (I used an off the shelf nut, turned thinner on the lathe)

A tommy bar in the spindle side hole and a wrench on the nut, with the drawbar loosened, will gently remove the arbor with no impacts.

Offline uuu

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Re: Machining an arbor blank
« Reply #17 on: January 28, 2025, 03:05:33 PM »
Aha!  MT5 is bigger than I've encountered (my current lathe is MT4).  And alas adapters are more expensive than I had previously listed.

If you have a friend with an MT2-equipped lathe and can beg some machining time, that would be the most straightforward way to go.

Wilf 

Offline Charles Lamont

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Re: Machining an arbor blank
« Reply #18 on: January 28, 2025, 03:58:49 PM »
There will come a time when you need to machine something between centres, so a reducing sleeve, 5 to 2 MT or 5 to 3 and 3 to 2 to give more options would not be a bad investment anyway.

Offline john mills

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Re: Machining an arbor blank
« Reply #19 on: January 28, 2025, 08:08:12 PM »
If you want a centre in the lathe chuck then turn a stepped parallel piece of steel  the step to stop it moving back in the chuck and turn the centre
60 deg point then you know it is running true

Offline redhouseluv

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Re: Machining an arbor blank
« Reply #20 on: January 28, 2025, 08:22:31 PM »
I made some investment in some reducing sleeves and and actual MT5 centre as I can see me using them in future as Charles has pointed out. I should now be able to machine the arbor blank and turn between centres more successfully. The last time I tried was on the Stuart Sun crankshaft and it jumped out of the lathe and was nearly ruined
Best regards

Sanjay

Offline redhouseluv

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Re: Machining an arbor blank
« Reply #21 on: January 29, 2025, 09:16:46 PM »
This adaptor made life simpler - straight shank which goes in the chuck with an internal 2MT. I used Charles' method to angle the cross slide using the original arbor and then cut the angle on the blank, it worked a treat. I have a nice 'new to me' drill chuck to use after a year of sitting on the shelf!
Best regards

Sanjay

Offline Dave Otto

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Re: Machining an arbor blank
« Reply #22 on: January 29, 2025, 09:28:31 PM »
Nice! You made short work of that.

Dave

Offline Roger B

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Re: Machining an arbor blank
« Reply #23 on: January 31, 2025, 08:04:07 AM »
Good work, that's a nice little Rohm chuck  :)  :ThumbsUp:
Best regards

Roger

 

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