Thanks. I’m confused by your use of “walls”, 5 walls, 3-4 walls, etc. Can you elucidate? Are these square threads on the clamps? Just curious. I suspect they are harder to print than 60 degree threads. BTW, I verified that the bolt I need is 1/2-12, an odd size, but apparently used occasionally, esp in the UK and Australia I guess. -Bob Tucson AZ On Feb 7, 2023, at 03:24, Roger Whiteley via Discuss <discuss@lists.openscad.org> wrote: From: Roger Whiteley <roger.whiteley@me.com> Subject: [OpenSCAD] Re: Gear Making for a Toy Car Date: February 7, 2023 at 03:24:49 MST To: discuss@lists.openscad.org Reply-To: OpenSCAD general discussion Mailing-list <discuss@lists.openscad.org> @Bob Carlson. I print screw threads vertically - several components I make for our machines have printed screws: A clamp - all in PLA - the clamp part took a lot of (re)-designing to prevent bending [and snapping] under load. I print this screw with the following settings - this screw is 16mm in diameter with a pitch of about 4mm: 0.16mm layer height, 5 walls [2mm], Z seam random, infill 30% gyroid. The second one is a pinch clamp, again vertically printed in PLA, but its only 10mm in diameter, with a 2mm pitch, 3 walls at the same layer height and infill. Being so 'thin' it is prone to snapping at the thread root, so for the length of the screw thread I embed an empty 'cylinder', creating a void in the centre, the slicer sees this as a wall, so it gets the same processing applied - a 1.2mm walled hollow section, being cylindrical it has no stress raising corners and problem solved. Its invisible and nobody is any the wiser - I think I saw Angus on Maker's Muse You Tube channel doing something similar, so I'm not claiming originality. BTW random Z means there is no continuous seam up the thread in one place [but you knew that already :-)]. Printing gears is 'interesting', the change gears on a mini lathe are mostly injection moulded so have no directional alignment in the material, 3d printing straight gears results in much stronger gears owing to the wall alignment - but the weakest link is always supposed to be the woodruff key for a metal gear train in the event of a jam, not the teeth :-). Bevel gears are trickier, I print them on their back if they are large, or teeth down with a spacing ring to lift them off the print surface - we've had more issues with teeth shearing on bevel gears owing to the orientation - 3 to 4 walls, for a 4 inch bevel with 30 teeth we use 15% gyroid - from our experience gyroid infill works. Examples from the past: Myford lathes had 20dp machined cast iron gears with woodruff keys, but a 1974 Volvo 144 had a cam drive gear machined from tufnol + woodruff key, quiet, but it did strip eventually. HTH Roger. _______________________________________________ OpenSCAD mailing list To unsubscribe send an email to discuss-leave@lists.openscad.org

We're all metric in Oz, mate Andy On Wed, 8 Feb 2023, 6:01 am Bob Carlson, <bob@rjcarlson.com> wrote: > Thanks. I’m confused by your use of “walls”, 5 walls, 3-4 walls, etc. Can > you elucidate? > > Are these square threads on the clamps? Just curious. I suspect they are > harder to print than 60 degree threads. > > BTW, I verified that the bolt I need is 1/2-12, an odd size, but > apparently used occasionally, esp in the UK and Australia I guess. > > -Bob > Tucson AZ > > > > > On Feb 7, 2023, at 03:24, Roger Whiteley via Discuss < > discuss@lists.openscad.org> wrote: > > > *From: *Roger Whiteley <roger.whiteley@me.com> > *Subject: **[OpenSCAD] Re: Gear Making for a Toy Car* > *Date: *February 7, 2023 at 03:24:49 MST > *To: *discuss@lists.openscad.org > *Reply-To: *OpenSCAD general discussion Mailing-list < > discuss@lists.openscad.org> > > > @Bob Carlson. > > I print screw threads vertically - several components I make for our > machines have printed screws: > > A clamp - all in PLA - the clamp part took a lot of (re)-designing to > prevent bending [and snapping] under load. > > I print this screw with the following settings - this screw is 16mm in > diameter with a pitch of about 4mm: > > 0.16mm layer height, 5 walls [2mm], Z seam random, infill 30% gyroid. > > The second one is a pinch clamp, again vertically printed in PLA, but its > only 10mm in diameter, with a 2mm pitch, 3 walls at the same layer height > and infill. > > Being so 'thin' it is prone to snapping at the thread root, so for the > length of the screw thread I embed an empty 'cylinder', creating a void in > the centre, the slicer sees this as a wall, so it gets the same processing > applied - a 1.2mm walled hollow section, being cylindrical it has no stress > raising corners and problem solved. Its invisible and nobody is any the > wiser - I think I saw Angus on Maker's Muse You Tube channel doing > something similar, so I'm not claiming originality. > > BTW random Z means there is no continuous seam up the thread in one place > [but you knew that already :-)]. > > Printing gears is 'interesting', the change gears on a mini lathe are > mostly injection moulded so have no directional alignment in the material, > 3d printing straight gears results in much stronger gears owing to the wall > alignment - but the weakest link is always supposed to be the woodruff key > for a metal gear train in the event of a jam, not the teeth :-). > > Bevel gears are trickier, I print them on their back if they are large, or > teeth down with a spacing ring to lift them off the print surface - we've > had more issues with teeth shearing on bevel gears owing to the orientation > - 3 to 4 walls, for a 4 inch bevel with 30 teeth we use 15% gyroid - from > our experience gyroid infill works. > > Examples from the past: Myford lathes had 20dp machined cast iron gears > with woodruff keys, but a 1974 Volvo 144 had a cam drive gear machined from > tufnol + woodruff key, quiet, but it did strip eventually. > > HTH Roger. > > > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org > > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

And in the UK. It is just the US that use the old units. On Tue, 7 Feb 2023 at 22:41, Andy Cole <1943ajlc@gmail.com> wrote: > We're all metric in Oz, mate > Andy > > On Wed, 8 Feb 2023, 6:01 am Bob Carlson, <bob@rjcarlson.com> wrote: > >> Thanks. I’m confused by your use of “walls”, 5 walls, 3-4 walls, etc. Can >> you elucidate? >> >> Are these square threads on the clamps? Just curious. I suspect they are >> harder to print than 60 degree threads. >> >> BTW, I verified that the bolt I need is 1/2-12, an odd size, but >> apparently used occasionally, esp in the UK and Australia I guess. >> >> -Bob >> Tucson AZ >> >> >> >> >> On Feb 7, 2023, at 03:24, Roger Whiteley via Discuss < >> discuss@lists.openscad.org> wrote: >> >> >> *From: *Roger Whiteley <roger.whiteley@me.com> >> *Subject: **[OpenSCAD] Re: Gear Making for a Toy Car* >> *Date: *February 7, 2023 at 03:24:49 MST >> *To: *discuss@lists.openscad.org >> *Reply-To: *OpenSCAD general discussion Mailing-list < >> discuss@lists.openscad.org> >> >> >> @Bob Carlson. >> >> I print screw threads vertically - several components I make for our >> machines have printed screws: >> >> A clamp - all in PLA - the clamp part took a lot of (re)-designing to >> prevent bending [and snapping] under load. >> >> I print this screw with the following settings - this screw is 16mm in >> diameter with a pitch of about 4mm: >> >> 0.16mm layer height, 5 walls [2mm], Z seam random, infill 30% gyroid. >> >> The second one is a pinch clamp, again vertically printed in PLA, but its >> only 10mm in diameter, with a 2mm pitch, 3 walls at the same layer height >> and infill. >> >> Being so 'thin' it is prone to snapping at the thread root, so for the >> length of the screw thread I embed an empty 'cylinder', creating a void in >> the centre, the slicer sees this as a wall, so it gets the same processing >> applied - a 1.2mm walled hollow section, being cylindrical it has no stress >> raising corners and problem solved. Its invisible and nobody is any the >> wiser - I think I saw Angus on Maker's Muse You Tube channel doing >> something similar, so I'm not claiming originality. >> >> BTW random Z means there is no continuous seam up the thread in one place >> [but you knew that already :-)]. >> >> Printing gears is 'interesting', the change gears on a mini lathe are >> mostly injection moulded so have no directional alignment in the material, >> 3d printing straight gears results in much stronger gears owing to the wall >> alignment - but the weakest link is always supposed to be the woodruff key >> for a metal gear train in the event of a jam, not the teeth :-). >> >> Bevel gears are trickier, I print them on their back if they are large, >> or teeth down with a spacing ring to lift them off the print surface - >> we've had more issues with teeth shearing on bevel gears owing to the >> orientation - 3 to 4 walls, for a 4 inch bevel with 30 teeth we use 15% >> gyroid - from our experience gyroid infill works. >> >> Examples from the past: Myford lathes had 20dp machined cast iron gears >> with woodruff keys, but a 1974 Volvo 144 had a cam drive gear machined from >> tufnol + woodruff key, quiet, but it did strip eventually. >> >> HTH Roger. >> >> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

We (some of us) ARE comfortable with metric... On Tue, Feb 7, 2023 at 5:16 PM nop head <nop.head@gmail.com> wrote: > And in the UK. It is just the US that use the old units. > > On Tue, 7 Feb 2023 at 22:41, Andy Cole <1943ajlc@gmail.com> wrote: > >> We're all metric in Oz, mate >> Andy >> >> On Wed, 8 Feb 2023, 6:01 am Bob Carlson, <bob@rjcarlson.com> wrote: >> >>> Thanks. I’m confused by your use of “walls”, 5 walls, 3-4 walls, etc. >>> Can you elucidate? >>> >>> Are these square threads on the clamps? Just curious. I suspect they are >>> harder to print than 60 degree threads. >>> >>> BTW, I verified that the bolt I need is 1/2-12, an odd size, but >>> apparently used occasionally, esp in the UK and Australia I guess. >>> >>> -Bob >>> Tucson AZ >>> >>> >>> >>> >>> On Feb 7, 2023, at 03:24, Roger Whiteley via Discuss < >>> discuss@lists.openscad.org> wrote: >>> >>> >>> *From: *Roger Whiteley <roger.whiteley@me.com> >>> *Subject: **[OpenSCAD] Re: Gear Making for a Toy Car* >>> *Date: *February 7, 2023 at 03:24:49 MST >>> *To: *discuss@lists.openscad.org >>> *Reply-To: *OpenSCAD general discussion Mailing-list < >>> discuss@lists.openscad.org> >>> >>> >>> @Bob Carlson. >>> >>> I print screw threads vertically - several components I make for our >>> machines have printed screws: >>> >>> A clamp - all in PLA - the clamp part took a lot of (re)-designing to >>> prevent bending [and snapping] under load. >>> >>> I print this screw with the following settings - this screw is 16mm in >>> diameter with a pitch of about 4mm: >>> >>> 0.16mm layer height, 5 walls [2mm], Z seam random, infill 30% gyroid. >>> >>> The second one is a pinch clamp, again vertically printed in PLA, but >>> its only 10mm in diameter, with a 2mm pitch, 3 walls at the same layer >>> height and infill. >>> >>> Being so 'thin' it is prone to snapping at the thread root, so for the >>> length of the screw thread I embed an empty 'cylinder', creating a void in >>> the centre, the slicer sees this as a wall, so it gets the same processing >>> applied - a 1.2mm walled hollow section, being cylindrical it has no stress >>> raising corners and problem solved. Its invisible and nobody is any the >>> wiser - I think I saw Angus on Maker's Muse You Tube channel doing >>> something similar, so I'm not claiming originality. >>> >>> BTW random Z means there is no continuous seam up the thread in one >>> place [but you knew that already :-)]. >>> >>> Printing gears is 'interesting', the change gears on a mini lathe are >>> mostly injection moulded so have no directional alignment in the material, >>> 3d printing straight gears results in much stronger gears owing to the wall >>> alignment - but the weakest link is always supposed to be the woodruff key >>> for a metal gear train in the event of a jam, not the teeth :-). >>> >>> Bevel gears are trickier, I print them on their back if they are large, >>> or teeth down with a spacing ring to lift them off the print surface - >>> we've had more issues with teeth shearing on bevel gears owing to the >>> orientation - 3 to 4 walls, for a 4 inch bevel with 30 teeth we use 15% >>> gyroid - from our experience gyroid infill works. >>> >>> Examples from the past: Myford lathes had 20dp machined cast iron gears >>> with woodruff keys, but a 1974 Volvo 144 had a cam drive gear machined from >>> tufnol + woodruff key, quiet, but it did strip eventually. >>> >>> HTH Roger. >>> >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

You sure about that? Let's see...when I search for 1/2-12 screws I get this: https://britishfasteners.com/bsw-1-2-12-x-1-1-2-stainless-hex-screw-7793.html And what is BSW? *British Standard Whitworth* (*BSW*) is an imperial-unit <https://en.wikipedia.org/wiki/Imperial-unit>-based screw thread <https://en.wikipedia.org/wiki/Screw_thread> standard, devised and specified by Joseph Whitworth <https://en.wikipedia.org/wiki/Joseph_Whitworth> in 1841 and later adopted as a British Standard <https://en.wikipedia.org/wiki/British_Standard>. It was the world's first national screw thread standard, and is the basis for many other standards, such as BSF <https://en.wikipedia.org/wiki/British_Standard_Fine>, BSP <https://en.wikipedia.org/wiki/British_Standard_Pipe>, BSCon <https://en.wikipedia.org/w/index.php?title=British_Standard_Conduit&action=edit&redlink=1>, and BSCopper <https://en.wikipedia.org/w/index.php?title=British_Standard_Copper&action=edit&redlink=1>. So why are they selling it if nobody uses it? Interesting to note that BSW has a 55 deg thread pitch instead of 60 deg thread pitch, so the screws will not mate with US standard hardware even in cases where the dimensions and pitch are the same. Looks like British Standard Pipe is also based on imperial units, and looks like they are still in use and listed in ISO standard documents. On Tue, Feb 7, 2023 at 6:16 PM nop head <nop.head@gmail.com> wrote: > And in the UK. It is just the US that use the old units. > > On Tue, 7 Feb 2023 at 22:41, Andy Cole <1943ajlc@gmail.com> wrote: > >> We're all metric in Oz, mate >> Andy >> >> On Wed, 8 Feb 2023, 6:01 am Bob Carlson, <bob@rjcarlson.com> wrote: >> >>> Thanks. I’m confused by your use of “walls”, 5 walls, 3-4 walls, etc. >>> Can you elucidate? >>> >>> Are these square threads on the clamps? Just curious. I suspect they are >>> harder to print than 60 degree threads. >>> >>> BTW, I verified that the bolt I need is 1/2-12, an odd size, but >>> apparently used occasionally, esp in the UK and Australia I guess. >>> >>> -Bob >>> Tucson AZ >>> >>> >>> >>> >>> On Feb 7, 2023, at 03:24, Roger Whiteley via Discuss < >>> discuss@lists.openscad.org> wrote: >>> >>> >>> *From: *Roger Whiteley <roger.whiteley@me.com> >>> *Subject: **[OpenSCAD] Re: Gear Making for a Toy Car* >>> *Date: *February 7, 2023 at 03:24:49 MST >>> *To: *discuss@lists.openscad.org >>> *Reply-To: *OpenSCAD general discussion Mailing-list < >>> discuss@lists.openscad.org> >>> >>> >>> @Bob Carlson. >>> >>> I print screw threads vertically - several components I make for our >>> machines have printed screws: >>> >>> A clamp - all in PLA - the clamp part took a lot of (re)-designing to >>> prevent bending [and snapping] under load. >>> >>> I print this screw with the following settings - this screw is 16mm in >>> diameter with a pitch of about 4mm: >>> >>> 0.16mm layer height, 5 walls [2mm], Z seam random, infill 30% gyroid. >>> >>> The second one is a pinch clamp, again vertically printed in PLA, but >>> its only 10mm in diameter, with a 2mm pitch, 3 walls at the same layer >>> height and infill. >>> >>> Being so 'thin' it is prone to snapping at the thread root, so for the >>> length of the screw thread I embed an empty 'cylinder', creating a void in >>> the centre, the slicer sees this as a wall, so it gets the same processing >>> applied - a 1.2mm walled hollow section, being cylindrical it has no stress >>> raising corners and problem solved. Its invisible and nobody is any the >>> wiser - I think I saw Angus on Maker's Muse You Tube channel doing >>> something similar, so I'm not claiming originality. >>> >>> BTW random Z means there is no continuous seam up the thread in one >>> place [but you knew that already :-)]. >>> >>> Printing gears is 'interesting', the change gears on a mini lathe are >>> mostly injection moulded so have no directional alignment in the material, >>> 3d printing straight gears results in much stronger gears owing to the wall >>> alignment - but the weakest link is always supposed to be the woodruff key >>> for a metal gear train in the event of a jam, not the teeth :-). >>> >>> Bevel gears are trickier, I print them on their back if they are large, >>> or teeth down with a spacing ring to lift them off the print surface - >>> we've had more issues with teeth shearing on bevel gears owing to the >>> orientation - 3 to 4 walls, for a 4 inch bevel with 30 teeth we use 15% >>> gyroid - from our experience gyroid infill works. >>> >>> Examples from the past: Myford lathes had 20dp machined cast iron gears >>> with woodruff keys, but a 1974 Volvo 144 had a cam drive gear machined from >>> tufnol + woodruff key, quiet, but it did strip eventually. >>> >>> HTH Roger. >>> >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

Yes we can buy old imperial fasteners for legacy applications. For example a friend has a 200 year old house and needed to mend a door knob that used a Whitworth thread but I don't think anything new is designed with them. Plumbing pipe sizes and fasteners are still still imperial in the UK though. Probably due to the compatibility requirements. On Tue, 7 Feb 2023 at 23:44, Adrian Mariano <avm4@cornell.edu> wrote: > You sure about that? Let's see...when I search for 1/2-12 screws I get > this: > > > https://britishfasteners.com/bsw-1-2-12-x-1-1-2-stainless-hex-screw-7793.html > > And what is BSW? > > *British Standard Whitworth* (*BSW*) is an imperial-unit > <https://en.wikipedia.org/wiki/Imperial-unit>-based screw thread > <https://en.wikipedia.org/wiki/Screw_thread> standard, devised and > specified by Joseph Whitworth > <https://en.wikipedia.org/wiki/Joseph_Whitworth> in 1841 and later > adopted as a British Standard > <https://en.wikipedia.org/wiki/British_Standard>. It was the world's > first national screw thread standard, and is the basis for many other > standards, such as BSF > <https://en.wikipedia.org/wiki/British_Standard_Fine>, BSP > <https://en.wikipedia.org/wiki/British_Standard_Pipe>, BSCon > <https://en.wikipedia.org/w/index.php?title=British_Standard_Conduit&action=edit&redlink=1>, > and BSCopper > <https://en.wikipedia.org/w/index.php?title=British_Standard_Copper&action=edit&redlink=1>. > > > So why are they selling it if nobody uses it? Interesting to note that > BSW has a 55 deg thread pitch instead of 60 deg thread pitch, so the screws > will not mate with US standard hardware even in cases where the dimensions > and pitch are the same. Looks like British Standard Pipe is also based on > imperial units, and looks like they are still in use and listed in ISO > standard documents. > > > On Tue, Feb 7, 2023 at 6:16 PM nop head <nop.head@gmail.com> wrote: > >> And in the UK. It is just the US that use the old units. >> >> On Tue, 7 Feb 2023 at 22:41, Andy Cole <1943ajlc@gmail.com> wrote: >> >>> We're all metric in Oz, mate >>> Andy >>> >>> On Wed, 8 Feb 2023, 6:01 am Bob Carlson, <bob@rjcarlson.com> wrote: >>> >>>> Thanks. I’m confused by your use of “walls”, 5 walls, 3-4 walls, etc. >>>> Can you elucidate? >>>> >>>> Are these square threads on the clamps? Just curious. I suspect they >>>> are harder to print than 60 degree threads. >>>> >>>> BTW, I verified that the bolt I need is 1/2-12, an odd size, but >>>> apparently used occasionally, esp in the UK and Australia I guess. >>>> >>>> -Bob >>>> Tucson AZ >>>> >>>> >>>> >>>> >>>> On Feb 7, 2023, at 03:24, Roger Whiteley via Discuss < >>>> discuss@lists.openscad.org> wrote: >>>> >>>> >>>> *From: *Roger Whiteley <roger.whiteley@me.com> >>>> *Subject: **[OpenSCAD] Re: Gear Making for a Toy Car* >>>> *Date: *February 7, 2023 at 03:24:49 MST >>>> *To: *discuss@lists.openscad.org >>>> *Reply-To: *OpenSCAD general discussion Mailing-list < >>>> discuss@lists.openscad.org> >>>> >>>> >>>> @Bob Carlson. >>>> >>>> I print screw threads vertically - several components I make for our >>>> machines have printed screws: >>>> >>>> A clamp - all in PLA - the clamp part took a lot of (re)-designing to >>>> prevent bending [and snapping] under load. >>>> >>>> I print this screw with the following settings - this screw is 16mm in >>>> diameter with a pitch of about 4mm: >>>> >>>> 0.16mm layer height, 5 walls [2mm], Z seam random, infill 30% gyroid. >>>> >>>> The second one is a pinch clamp, again vertically printed in PLA, but >>>> its only 10mm in diameter, with a 2mm pitch, 3 walls at the same layer >>>> height and infill. >>>> >>>> Being so 'thin' it is prone to snapping at the thread root, so for the >>>> length of the screw thread I embed an empty 'cylinder', creating a void in >>>> the centre, the slicer sees this as a wall, so it gets the same processing >>>> applied - a 1.2mm walled hollow section, being cylindrical it has no stress >>>> raising corners and problem solved. Its invisible and nobody is any the >>>> wiser - I think I saw Angus on Maker's Muse You Tube channel doing >>>> something similar, so I'm not claiming originality. >>>> >>>> BTW random Z means there is no continuous seam up the thread in one >>>> place [but you knew that already :-)]. >>>> >>>> Printing gears is 'interesting', the change gears on a mini lathe are >>>> mostly injection moulded so have no directional alignment in the material, >>>> 3d printing straight gears results in much stronger gears owing to the wall >>>> alignment - but the weakest link is always supposed to be the woodruff key >>>> for a metal gear train in the event of a jam, not the teeth :-). >>>> >>>> Bevel gears are trickier, I print them on their back if they are large, >>>> or teeth down with a spacing ring to lift them off the print surface - >>>> we've had more issues with teeth shearing on bevel gears owing to the >>>> orientation - 3 to 4 walls, for a 4 inch bevel with 30 teeth we use 15% >>>> gyroid - from our experience gyroid infill works. >>>> >>>> Examples from the past: Myford lathes had 20dp machined cast iron gears >>>> with woodruff keys, but a 1974 Volvo 144 had a cam drive gear machined from >>>> tufnol + woodruff key, quiet, but it did strip eventually. >>>> >>>> HTH Roger. >>>> >>>> >>>> _______________________________________________ >>>> OpenSCAD mailing list >>>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>>> >>>> _______________________________________________ >>>> OpenSCAD mailing list >>>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

Roger. 

On Tue, Feb 07, 2023 at 06:43:27PM -0500, Adrian Mariano wrote: > You sure about that? Let's see...when I search for 1/2-12 screws I get > this: > https://britishfasteners.com/bsw-1-2-12-x-1-1-2-stainless-hex-screw-7793.html > So why are they selling it if nobody uses it? Maybe because out here we occasionally need to repair stuff made in the USA? I'm guessing that there are specialized machine-screw shops in the USA that also carry M3, M4 ... Or when you get something that uses a metric screw that needs replacing, you just toss the whole thing? Still, in GB I'd think you're more likely to find people using non-metric screws than say in Germany. Roger. -- ** R.E.Wolff@BitWizard.nl ** https://www.BitWizard.nl/ ** +31-15-2049110 ** ** Delftechpark 11 2628 XJ Delft, The Netherlands. KVK: 27239233 ** f equals m times a. When your f is steady, and your m is going down your a is going up. -- Chris Hadfield about flying up the space shuttle.

Roger. 

On Wed, Feb 08, 2023 at 09:20:05AM +0000, nop head wrote: > Plumbing pipe sizes and fasteners are still still imperial in the UK > though. Probably due to the compatibility requirements. Electrical tubes here in NL are called "19mm" to pretend they are metric, but in reality of course that 3/4 inch. Roger. -- ** R.E.Wolff@BitWizard.nl ** https://www.BitWizard.nl/ ** +31-15-2049110 ** ** Delftechpark 11 2628 XJ Delft, The Netherlands. KVK: 27239233 ** f equals m times a. When your f is steady, and your m is going down your a is going up. -- Chris Hadfield about flying up the space shuttle.

     Roger.

Or crusty old plumbers. On Wed, Feb 8, 2023, 17:25 Rogier Wolff <R.E.Wolff@bitwizard.nl> wrote: > On Tue, Feb 07, 2023 at 06:43:27PM -0500, Adrian Mariano wrote: > > You sure about that? Let's see...when I search for 1/2-12 screws I get > > this: > > > > https://britishfasteners.com/bsw-1-2-12-x-1-1-2-stainless-hex-screw-7793.html > > > So why are they selling it if nobody uses it? > > Maybe because out here we occasionally need to repair stuff made in > the USA? I'm guessing that there are specialized machine-screw shops > in the USA that also carry M3, M4 ... > > Or when you get something that uses a metric screw that needs > replacing, you just toss the whole thing? > > Still, in GB I'd think you're more likely to find people using > non-metric screws than say in Germany. > > Roger. > > -- > ** R.E.Wolff@BitWizard.nl ** https://www.BitWizard.nl/ ** +31-15-2049110 > ** > ** Delftechpark 11 2628 XJ Delft, The Netherlands. KVK: 27239233 ** > f equals m times a. When your f is steady, and your m is going down > your a is going up. -- Chris Hadfield about flying up the space shuttle. > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

 On Tue, Feb 07, 2023 at 06:43:27PM -0500, Adrian Mariano wrote:

 screws I get

 https://britishfasteners.com/bsw-1-2-12-x-1-1-2-stainless-hex-screw-7793.html

 Maybe because out here we occasionally need to repair stuff made in
 the USA? I'm guessing that there are specialized machine-screw shops
 in the USA that also carry M3, M4 ...

 Or when you get something that uses a metric screw that needs
 replacing, you just toss the whole thing?

 Still, in GB I'd think you're more likely to find people using
 non-metric screws than say in Germany.

         Roger.

 -- 
 ** R.E.Wolff@BitWizard.nl ** https://www.BitWizard.nl/
 <https://www.BitWizard.nl/> ** +31-15-2049110 **
 **    Delftechpark 11 2628 XJ  Delft, The Netherlands.  KVK:
 27239233    **
 f equals m times a. When your f is steady, and your m is going down
 your a is going up.  -- Chris Hadfield about flying up the space
 shuttle.
 _______________________________________________
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Whitworth bolts are used in applications where a tight fit and precision are required. They are typically used in applications such as machinery and mechanical engineering, as well as in historic restoration projects. The rounded profile of Whitworth bolts provides a more precise fit compared to other thread profiles, and they are also more resistant to vibration loosening. On 08/02/2023 10:19, Tim Hawkins wrote: > Or crusty old plumbers. > > On Wed, Feb 8, 2023, 17:25 Rogier Wolff <R.E.Wolff@bitwizard.nl> wrote: > > On Tue, Feb 07, 2023 at 06:43:27PM -0500, Adrian Mariano wrote: > > You sure about that?  Let's see...when I search for 1/2-12 > screws I get > > this: > > > > https://britishfasteners.com/bsw-1-2-12-x-1-1-2-stainless-hex-screw-7793.html > > > So why are they selling it if nobody uses it? > > Maybe because out here we occasionally need to repair stuff made in > the USA? I'm guessing that there are specialized machine-screw shops > in the USA that also carry M3, M4 ... > > Or when you get something that uses a metric screw that needs > replacing, you just toss the whole thing? > > Still, in GB I'd think you're more likely to find people using > non-metric screws than say in Germany. > >         Roger. > > -- > ** R.E.Wolff@BitWizard.nl ** https://www.BitWizard.nl/ > <https://www.BitWizard.nl/> ** +31-15-2049110 ** > **    Delftechpark 11 2628 XJ  Delft, The Netherlands.  KVK: > 27239233    ** > f equals m times a. When your f is steady, and your m is going down > your a is going up.  -- Chris Hadfield about flying up the space > shuttle. > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org > > > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email todiscuss-leave@lists.openscad.org