Author Topic: Sensitive Tapping Machine  (Read 2265 times)

Offline cfellows

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Sensitive Tapping Machine
« on: April 28, 2018, 06:14:52 AM »
I hate tapping.  Found this video of a sensitive tapping machine.

https://youtu.be/9yXLG8xwfF4

Doesn't look like it would be too hard to make a downsized version of this.
So many projects, so little time...

Offline Noitoen

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Re: Sensitive Tapping Machine
« Reply #1 on: April 28, 2018, 09:23:37 AM »

Offline ShopShoe

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Re: Sensitive Tapping Machine
« Reply #2 on: April 28, 2018, 01:30:26 PM »
Hi Chuck,

Glad to see you again!

As soon as I saw the linked video, I was reminded of the transmission from an old riding mower I had. It used cones for a drive system, too. I think Brian Rupnow posted a 3-D model of the parts sometime in the past.

Does anyone else think that might work?

Regards, and keep building.

ShopShoe

Offline Jasonb

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Re: Sensitive Tapping Machine
« Reply #3 on: April 28, 2018, 07:57:31 PM »
Westbury used a similar transmission on his model road roller, ideal for quick direction changes when going back and forth.

Offline Mcgyver

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Re: Sensitive Tapping Machine
« Reply #4 on: April 28, 2018, 08:02:52 PM »
If you are interested in them, there was an article on Hamiltons in the Jan/Feb issue of Home Shop Machinist.  It was a particularly good issue.  (one of mine made the cover  ;D ;D ;D  )

Offline cfellows

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Re: Sensitive Tapping Machine
« Reply #5 on: April 30, 2018, 01:10:54 AM »
Thanks, guys.  I stopped my subscription to HSM a couple of years ago, so I don't have access to the Jan-Feb issue.  There's a copy for sale on Ebay but the guy wants $14.00 + shipping.

I've come up with a drawing with an alternative design.  The disks are 1.75" diameter and the drive roller is 1/2" diameter with a rubber o-ring fitted.   This tapping machine would be used for taps ranging in size from 1-73 up to maybe 8-32.

 
So many projects, so little time...

Offline Noitoen

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Re: Sensitive Tapping Machine
« Reply #6 on: April 30, 2018, 10:49:10 AM »
Instead of an o-ring, you could use a small caster rubber wheel or use a metal wheel and 2 rubber discs like the ones used to back the sanding discs on small angle grinders.
« Last Edit: April 30, 2018, 10:53:36 AM by Noitoen »

Offline ddmckee54

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Re: Sensitive Tapping Machine
« Reply #7 on: May 08, 2018, 06:49:59 PM »
You plan on clamping that O-ring down somehow?  I would think you'd get an awful lot of slippage if you didn't, plus you don't have a lot of drive area with an O-ring.  Maybe a short length of rubber tubing on some type expanding mandrel?  I've got sanding drums where the drive mandrel isn't much more than a threaded rod with a nut and washer on the end of it.

I know slippage would be a good thing with an itty-bitty tap, but an 8-32 tap in a stubborn material might require more torque than your O-ring could provide.

My $0.02 worth,
Don

Offline Doc

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Re: Sensitive Tapping Machine
« Reply #8 on: May 09, 2018, 02:50:25 AM »
Chuck I think this will be my next little equipment build as soon as I finish my small carbide grinders. I probably will try and use the same motor as I am using in the carbide grinders. I like the concept you are looking at. I'll throw something together in CAD and see what we can come up with. Thanks for posting the video link appreciated!  :ThumbsUp:

Offline Doc

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Re: Sensitive Tapping Machine
« Reply #9 on: May 09, 2018, 03:02:46 AM »
Thanks, guys.  I stopped my subscription to HSM a couple of years ago, so I don't have access to the Jan-Feb issue.  There's a copy for sale on Ebay but the guy wants $14.00 + shipping.

I've come up with a drawing with an alternative design.  The disks are 1.75" diameter and the drive roller is 1/2" diameter with a rubber o-ring fitted.   This tapping machine would be used for taps ranging in size from 1-73 up to maybe 8-32.


By using a  smaller drive wheel on the disk you could make the torque out put variable by moving it inwards for less and out wards for more. Of coarse the rpm would also vary. Just a thought. Right now you would have over 2 to 1 depending where its tracking.

 

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