Thread cutting

This forum is for general discussion about Aspire
User avatar
Ms Wolffie
Vectric Wizard
Posts: 2695
Joined: Sat Mar 31, 2012 10:41 pm
Model of CNC Machine: Blue Elephant 1325, Shark HD Pro
Location: Tully Heads, Wet Tropics, Queensland, Australia

Thread cutting

Post by Ms Wolffie »

Do anyone know whether someone has ever done a gadget for thread cutting?
Cheers
Wolffie

Whatshammacallit
Cut3D, VCarvePro 6.5, Aspire4, PhotoVCarve, Corel Graphics Suite X6

ger21
Vectric Wizard
Posts: 1592
Joined: Sun Sep 16, 2007 2:59 pm
Model of CNC Machine: Custom DIY
Location: Lake St Clair, MI, USA
Contact:

Re: Thread cutting

Post by ger21 »

Gerry - http://www.thecncwoodworker.com

User avatar
FixitMike
Vectric Wizard
Posts: 2173
Joined: Sun Apr 17, 2011 5:21 am
Model of CNC Machine: Shark Pro Plus (retired)
Location: Burien, WA USA

Re: Thread cutting

Post by FixitMike »

I've used Paul Rowntree's Gadget. It requires a special thread cutter. Called a Single Profile Thread mill. Here's some, but I don't know about a down under source.
https://www.mscdirect.com/browse/tn/Thr ... 198214_c_S
Good judgement comes from experience.
Experience comes from bad judgement.

PaulRowntree
Vectric Wizard
Posts: 1687
Joined: Sun Oct 24, 2010 7:28 pm
Model of CNC Machine: homebuilt 4'x2' (Mach3+G540)
Location: Guelph, Ontario
Contact:

Re: Thread cutting

Post by PaulRowntree »

Were you thinking of a V-cutter on a 4th rotary axis?
Paul Rowntree
WarpDriver, StandingWave, Topo and gadgets available at PaulRowntree.weebly.com

Bobtail Farm
Vectric Craftsman
Posts: 285
Joined: Mon Dec 01, 2014 3:53 pm
Model of CNC Machine: Homemade

Re: Thread cutting

Post by Bobtail Farm »

Paul:

i do/am (thinking of a v-cutter on a rotary) for a male thread on dowel. Actually, a v-cutter without the point to match an ACME thread... to create longer threaded dowel than i can get on my machine (z-limits). and a similar profile on a side cutter when using your gadget for the female threads
Brian.

PaulRowntree
Vectric Wizard
Posts: 1687
Joined: Sun Oct 24, 2010 7:28 pm
Model of CNC Machine: homebuilt 4'x2' (Mach3+G540)
Location: Guelph, Ontario
Contact:

Re: Thread cutting

Post by PaulRowntree »

Bobtail Farm wrote:Paul:

i do/am (thinking of a v-cutter on a rotary) for a male thread on dowel. Actually, a v-cutter without the point to match an ACME thread... to create longer threaded dowel than i can get on my machine (z-limits). and a similar profile on a side cutter when using your gadget for the female threads
Brian.
There was a very nice example of this posted, the result was a beautiful bolt the size of your arm. Will see if I can find it. It should be a straightforward wrapped job (but I haven't done it). Others have made bench vises this way.
Paul Rowntree
WarpDriver, StandingWave, Topo and gadgets available at PaulRowntree.weebly.com

ger21
Vectric Wizard
Posts: 1592
Joined: Sun Sep 16, 2007 2:59 pm
Model of CNC Machine: Custom DIY
Location: Lake St Clair, MI, USA
Contact:

Re: Thread cutting

Post by ger21 »

You could hand code it in 3-4 lines.

G1 X10 A36000

will cut a 10" long 10tpi thread
Gerry - http://www.thecncwoodworker.com

Bobtail Farm
Vectric Craftsman
Posts: 285
Joined: Mon Dec 01, 2014 3:53 pm
Model of CNC Machine: Homemade

Thread cutting

Post by Bobtail Farm »

thank you all, even though I think I "hijacked" the thread.
Brian.

Tailmaker
Vectric Wizard
Posts: 698
Joined: Sun Jun 16, 2013 4:40 am
Model of CNC Machine: Home Built 4-axis Router
Location: Fort Collins, CO

Re: Thread cutting

Post by Tailmaker »

Actually, no gadget required. The spiral ramp tool path does the job. That said, the generated g-code needs a minor edit to prevent to thread cutter from getting yanked out vertically at the end of the thread and making a groove (but even that would not ruin the thread altogether). The attached g-code was edited to do just that, i.e. move the bit away from the bolt and to the center of the nut before going back up. If Vectric would allow a lead-out move for spiral ramp tool paths that would probably be solved....

BoltNut1.crv3d
(2.02 MiB) Downloaded 301 times
BoltNutG-Code.zip
(8.76 KiB) Downloaded 277 times
Threads were cut with the Magnate 796 thread cutter bit (about $18). The file has a radial clearance of 0.1mm between nut and bolt but that is still a bit tight given the fuzziness of the wood surface. Some wax lubrication helps.

The new 9.5 version helical arcs option makes it even nicer but even before with many small linear movements it would work.
Attachments
DSC01384.JPG
DSC01387.JPG
DSC01390.JPG

Tailmaker
Vectric Wizard
Posts: 698
Joined: Sun Jun 16, 2013 4:40 am
Model of CNC Machine: Home Built 4-axis Router
Location: Fort Collins, CO

Re: Thread cutting

Post by Tailmaker »

Forgot to mention...conventional direction makes a right-hand thread while climb direction makes a left-hand thread.

Tailmaker
Vectric Wizard
Posts: 698
Joined: Sun Jun 16, 2013 4:40 am
Model of CNC Machine: Home Built 4-axis Router
Location: Fort Collins, CO

Re: Thread cutting

Post by Tailmaker »

Tailmaker wrote:Forgot to mention...conventional direction makes a right-hand thread while climb direction makes a left-hand thread.
That is true for the nut...For the bolt it is the opposite. climb direction makes a right hand and conventional direction a left hand thread.

John Murphy
Vectric Wizard
Posts: 678
Joined: Thu Jan 15, 2009 1:08 am
Model of CNC Machine: AXYZ 5010
Location: Maryhill Ontario Canada
Contact:

Re: Thread cutting

Post by John Murphy »

HI Guys.
I've used Paul's gadget with great results.

I used a boring bar set to do the cutting https://www.busybeetools.com/products/h ... b3334.html

John
Attachments
20180906_172047-resize.jpg

crpoj13
Vectric Apprentice
Posts: 55
Joined: Wed Sep 04, 2013 1:15 pm
Model of CNC Machine: cncrouterparts 2448

Re: Thread cutting

Post by crpoj13 »

I too have used Paul's gadget and then I took info from it and ran it on my 4 axis rotary. I have plans to make a clamp vise on my work bench utilizing a large diameter screw, just for fun. Was unable to attach my video of me spinning the nut down the thread body. That thread body is 3 inch Pitch Diameter and .3125 Thread Pitch. The nut is 1 inch thick.
4 axis threading.JPG

Bobtail Farm
Vectric Craftsman
Posts: 285
Joined: Mon Dec 01, 2014 3:53 pm
Model of CNC Machine: Homemade

Re: Thread cutting

Post by Bobtail Farm »

crpoj13:
Neat. Any clues as to what/how you "took info from [Paul Rowntree's thread gadget]" to use in running a rotary toolpath? Interested to see how it might differ from Gert's suggestion (august 22nd) "hand coding" G-code.
It also looks like you used a v-bit. I've used a v-bit with smaller diameter threads with reasonable success. However, I've had it in mind for some time to use a flat bottom bit with 29 degree (if I recall correctly) sides to cut a ACME trapezodial thread on a larger diameter rod like you've done with the v-bit to use for bench vises and all sorts of applications where i use either a small diameter wood or metal (all) threaded rod.
Thanks in advance. And appreciate the inspiration - that project has been lagging on my list.
Regards,
Brian.

crpoj13
Vectric Apprentice
Posts: 55
Joined: Wed Sep 04, 2013 1:15 pm
Model of CNC Machine: cncrouterparts 2448

Re: Thread cutting

Post by crpoj13 »

All I did was took values from the "Current Thread Description" window that populates from using the gadget. I use those min and max values for my diameters for the rotary work. Hand coding is fine as well, I just prefer to doing it via software. I am using a 90 degree V bit for the rotary work and a side 90 degree V bit for the vertical 3 axis work. I'm tossing around the idea of stabilizing the wood 1st, I am getting some movement due to humidity in my area that has caused the threads to tighten some over time.

Post Reply