I made a parting tool holder that holds the tool upside down on the back of the cross slide and run the motor backwards (with a clamp for the screw-on chuck). ?This works great. We had long discussions on the Boxford Users Group (io). ?I think the main difference is that the swarf drops out with gravity and does not get jammed in beside the cutting tool. There are many theories. ?Often I just use an ordinary QCTP and only bother to set up the reverse rotation if I am having trouble.
--
Evan
Lathe: 1955 Boxford Model A with screw cutting gearbox, power feed with several accessories, hand tools and a pillar drill press.
Try my Free Online Gear train Software:
You enter a thread pitch or TPI and it shows you a range of gear trains and gearbox setting to use and even a scale drawing of the gear train.
It also includes calculations for taper turning by the tailstock offset method, and cutting speeds.
It includes the specifications for many thread types eg metric, UNC, BSW, and BA.
Displays drill sizes for tapping threads at any percent thread depth (with full explanations).
My YouTube Channel and Playlist about using an engineers lathe: ?
Project to build a Greek Hero steam engine and measure its power output:?
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I too use a "norman" style tool post, but mine is mounted on a 1.0 inch diameter post. I works quite well and I have been using it for about?20?years now. Drawings and photos are available.? Regards, John?Mattis (retired mechanical engineer)
On Fri, Apr 25, 2025 at 10:50?AM Mark Kimball via <markkimball51= [email protected]> wrote: I made a Norman style QCTP based on Ralph Patterson's drawings.? It has a large (~1.25") mounting post.? The tool holders are pretty beefy as well.? This all provides worry-free parting off, as long as the tool is sharp and at the proper height, and the compound gibs are properly adjusted.?
?
The first commercial QCTP I got for my lathe was just too lightweight.? That thing DID cause all kinds of headaches.
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I've found parting to be much easier with a "T" shaped HSS blade, mounted with the minimum length of blade protruding out of the tool holder. It's worth the effort of modifying the tool holder to properly mount the blade.
?
Roy
?
?
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I made a Norman style QCTP based on Ralph Patterson's drawings.? It has a large (~1.25") mounting post.? The tool holders are pretty beefy as well.? This all provides worry-free parting off, as long as the tool is sharp and at the proper height, and the compound gibs are properly adjusted.?
?
The first commercial QCTP I got for my lathe was just too lightweight.? That thing DID cause all kinds of headaches.
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I part Al all the time with little problem...
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On 4/25/2025 11:13 AM, Ralph Hulslander via groups.io wrote: Once I parted aluminium successfuly, like a piece of butter, since then I
have had to use a hack saw for aluminium or steel.
On Thu, Apr 24, 2025, 10:56 PM Mike W via groups.io <mike.wilkens=
[email protected]> wrote:
Yesterday I had to part off some aluminum (6061), 24mm diameter, and
remembered that I had had endless trouble previously with this operation -
regardless of material.
So this time I took off the quick change toolpost and re-installed the
original four-way. The parting off process went smoothly with none of the
problems I'd encountered before. It did get jammed once - I was running
the motor too slowly. (I don't have a low gear anymore.) Didn't matter if
I used oil or not, or went fast or slow. It was as easy as any other
operation.
Something about how the QC extends over the compound - one of the weak
parts of these lathes - lessens the rigidity necessary to do this operation
well.
-Mike
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I have had great success with a parting-off tool that takes a push-in insert (all metals). Always do it close to the chuck and never with a fixed steady or a tailstock centre.
Rgrds
MFS?
On Fri, 25 Apr 2025 at 17:13, Ralph Hulslander via <rhulslander= [email protected]> wrote: Once I parted aluminium successfuly, like a piece of butter, since then I have had to use a hack saw for aluminium or steel.
Yesterday I had to part off some aluminum (6061), 24mm diameter, and remembered that I had had endless trouble previously with this operation - regardless of material.
?
So this time I took off the quick change toolpost and re-installed the original four-way.? The parting off process went smoothly with none of the problems I'd encountered before.? It did get jammed once - I was running the motor too slowly.? (I don't have a low gear anymore.)? Didn't matter if I used oil or not, or went fast or slow.? It was as easy as any other operation.
?
Something about how the QC extends over the compound - one of the weak parts of these lathes - lessens the rigidity necessary to do this operation well.
?
-Mike
?
|
Once I parted aluminium successfuly, like a piece of butter, since then I have had to use a hack saw for aluminium or steel.
Yesterday I had to part off some aluminum (6061), 24mm diameter, and remembered that I had had endless trouble previously with this operation - regardless of material.
?
So this time I took off the quick change toolpost and re-installed the original four-way.? The parting off process went smoothly with none of the problems I'd encountered before.? It did get jammed once - I was running the motor too slowly.? (I don't have a low gear anymore.)? Didn't matter if I used oil or not, or went fast or slow.? It was as easy as any other operation.
?
Something about how the QC extends over the compound - one of the weak parts of these lathes - lessens the rigidity necessary to do this operation well.
?
-Mike
?
|
Yesterday I had to part off some aluminum (6061), 24mm diameter, and remembered that I had had endless trouble previously with this operation - regardless of material.
?
So this time I took off the quick change toolpost and re-installed the original four-way.? The parting off process went smoothly with none of the problems I'd encountered before.? It did get jammed once - I was running the motor too slowly.? (I don't have a low gear anymore.)? Didn't matter if I used oil or not, or went fast or slow.? It was as easy as any other operation.
?
Something about how the QC extends over the compound - one of the weak parts of these lathes - lessens the rigidity necessary to do this operation well.
?
-Mike
?
|
Re: New Lead Screw Bearings And Installing A Mystery Rod
I dunno what's up with that hex rod but I did something similar to address backlash in the lead screw.? I didn't use angular contact bearings, I used thrust bearings.? I did it by machining a replacement bearing? block, which has the same outside dimensions as the OEM version.? I saw no point in using steel so it's 6061 aluminum.
?
The job was done to improve the performance of my LS hand crank mod.? My LS is 16TPI so the Z motion is a little coarse compared to the cross slide and compound feed screws @20TPI.? I also added a DRO on the Z axis so it can function as a long-throw compound.....for some things.? I still need the top slide for threading so it's not going in the scrap bin.? But for a lot of stuff I can use the plinth, which is good in terms of improved rigidity.
?
Mark
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Re: New Lead Screw Bearings And Installing A Mystery Rod
OK, that works. Yes, I Have seen this. That guy does some fabulous stuff. I have been subscribed for quite a while.
Thanks.
Sent from ProtonMail, Swiss-based encrypted email.
Sent with Proton Mail secure email.
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On Monday, April 21st, 2025 at 11:54 PM, mike allen via groups.io <animal@...> wrote: It's not you , it's me . that means that I sent a machining link to
a bunch of buds instead of the music link I thought I was sending .
try this
For some unknown reason I have been unable to post comments on youtube
now for a couple of years & I also no longer have the button to hit to
send the video to my TV .
sorry bout the link
animal
On 4/21/25 11:49 PM, Phil via groups.io wrote:
Is it just me?
I'm not seeing any kind of link. Youtube or something?
Sent from ProtonMail, Swiss-based encrypted email.
Sent with Proton Mail secure email.
On Monday, April 21st, 2025 at 11:45 PM, mike allen via groups.io animal@... wrote:
I just kinda tripped over this earlier tonite figured there may be some
vids here that some of ya folks may be interested in .
this is the one I watched , but the guy/gal has lots of good vids
|
Re: New Lead Screw Bearings And Installing A Mystery Rod
It's not you , it's me . that means that I sent a machining link to
a bunch of buds instead of the music link I thought I was sending .
try this
For some unknown reason I have been unable to post comments on youtube
now for a couple of years & I also no longer have the button to hit to
send the video to my TV .
sorry bout the link
animal
toggle quoted message
Show quoted text
On 4/21/25 11:49 PM, Phil via groups.io wrote: Is it just me?
I'm not seeing any kind of link. Youtube or something?
Sent from ProtonMail, Swiss-based encrypted email.
Sent with Proton Mail secure email.
On Monday, April 21st, 2025 at 11:45 PM, mike allen via groups.io <animal@...> wrote:
I just kinda tripped over this earlier tonite figured there may be some
vids here that some of ya folks may be interested in .
this is the one I watched , but the guy/gal has lots of good vids
|
Re: New Lead Screw Bearings And Installing A Mystery Rod
Is it just me?
I'm not seeing any kind of link. Youtube or something?
Sent from ProtonMail, Swiss-based encrypted email.
Sent with Proton Mail secure email.
toggle quoted message
Show quoted text
On Monday, April 21st, 2025 at 11:45 PM, mike allen via groups.io <animal@...> wrote: I just kinda tripped over this earlier tonite figured there may be some
vids here that some of ya folks may be interested in .
this is the one I watched , but the guy/gal has lots of good vids
|
New Lead Screw Bearings And Installing A Mystery Rod
I just kinda tripped over this earlier tonite? figured there may be some
vids here that some of ya folks may be interested in .
this is the one I watched , but the guy/gal has lots of good vids
|
The basic problem is the design of the carriage!? The vertical play is adjusted with clamp & jack screws vaguely locating the clamp strips on the underside of the bed; that's common on larger lathes, doesn't scale down well for 7x? lathes. The fix is to replace the screw adjustment system with shims & have the clamp screws tight. It can get a little tedious if the underside of the bed is uneven, requiring some work with? curved files, "rifflers."
?
Roy
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I made something similar for one particular application and find I use it quite a bit for general turning.
?
Mark
?
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I have made 2 new and longer pressboards under the saddle in both x directions.?
They have also contact on outside to saddle.
2 of the 3 fasten screws on the front are now available from upper side for better control of the press.
Back side is no problem.
My lead screw is now manual operated.
(Much better than the big Hand wheel in front)
Johannes
Mexico
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That could be related to play in the saddle gibs.
Has somebody made a lead screw to be installed in the middle of the bed ?
I have looked into Youtube, but not found what I wanted.
The problem is twisting of the saddle when I return the clock wheel cutter.
( 144 teeth on an 88 mm diameter plate gives not much room for error)
The leadscrew shall be manual twisted.
Johannes
Mexico
|
That could be related to play in the saddle gibs.
Has somebody made a lead screw to be installed in the middle of the bed ?
I have looked into Youtube, but not found what I wanted.
The problem is twisting of the saddle when I return the clock wheel cutter.
( 144 teeth on an 88 mm diameter plate gives not much room for error)
The leadscrew shall be manual twisted.
Johannes
Mexico
|
Has somebody made a lead screw to be installed in the middle of the bed ?
I have looked into Youtube, but not found what I wanted.
The problem is twisting of the saddle when I return the clock wheel cutter.
( 144 teeth on an 88 mm diameter plate gives not much room for error)
The leadscrew shall be manual twisted.
Johannes
Mexico
|
Drilling a 486 CPU is like drilling glass, the 486 is probably harder.? Same technique would be needed, diamond drill, water, patience etc. ? Here’s an old page for making a keychain from a 486, basically solder a wire to the back.? ? https://web.archive.org/web/20010410093643/http://www2.apex.net/users/timwhita/keychain.html ? Not sure why they took a Dremel to the pins, you can unsolder those.? Note that the metal plate on the back of the chip is soldered on, unsolder that and fill it with resin so you can see the actual CPU. ? Tony ? ? ?
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From: [email protected] <[email protected]> On Behalf Of Jacques Savard via groups.io
Sent: Sunday, 23 March 2025 5:28 am
To: [email protected]
Subject: [7x12MiniLathe] dril a scp 486? Résultats de traductionRésultat de traductionI have some cpu 486 or pentium vintage version But impossible to drill a ho;e in the material Normal drill for Metll Nothing
Drill Diamand for glass or stained glass Nothing Do you have an idea please
Jack 47 71
it is exposy proly but very hard stouf
Any Advise Please
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It also reduces the heat generated in the tooth and washes away the swarf from the operation.? Ultrasonic drills also use a mist spray for these same reasons (but they don’t utilize diamonds bonded on the “bit”. ? Jerry F. ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Roy via groups.io
Sent: Sunday, March 23, 2025 4:33 PM
To: [email protected]
Subject: Re: [7x12MiniLathe] dril a scp 486? Diamond abrasive bits are actually diamond powder mechanically attached, not chemically bonded, to the bit body with nickel plating. When your dentist uses them, notice there's always a cooling water mist involved to protect the integrity of the bit.
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Evan
John Mattis
Johannes