Re: [Emc-users] Micro-switch repeatability

On 2/22/2016 9:15 AM, andy pugh wrote: > On 17 February 2016 at 17:14, Dave Cole wrote: >> Prox switches are just the opposite. Most are even waterproof. >> Prox switches are becoming very cheap. Someplace is trying to sell me >> some for about $10 each with a cable.

Re: [Emc-users] Micro-switch repeatability

On 17 February 2016 at 17:14, Dave Cole wrote: > Prox switches are just the opposite. Most are even waterproof. > Prox switches are becoming very cheap. Someplace is trying to sell me > some for about $10 each with a cable. > I've used Prox switches on very expensive

Re: [Emc-users] Micro-switch repeatability

I understand your situation. In light of what you said you might want to go with Prox switches and forget about mechanical microswitches. My reason is this: Small cheap mechanical microswitches are very easy to break and hard to mount, protect and adjust. Prox switches are just the opposite.

Re: [Emc-users] Micro-switch repeatability

tson [mailto:albertson.ch...@gmail.com] > > Sent: February-16-16 6:34 PM > > To: Enhanced Machine Controller (EMC) > > Subject: Re: [Emc-users] Micro-switch repeatability > > > > > > Look at how inkjet printers work. They need to trip a home switch so > that &

Re: [Emc-users] Micro-switch repeatability

On 02/17/2016 04:28 PM, Dave Cole wrote: > The other approach to take is to forget about home switches and do a > touch off on the work or the stops by using a probe. Yes, you are right. That would be a good solution. I may just want to clarify... The whole discussion is not about the correct

Re: [Emc-users] Micro-switch repeatability

The other approach to take is to forget about home switches and do a touch off on the work or the stops by using a probe. Mount the probe in in the spindle and touch off on the stops or the workpiece to obtain a zero position. There are some relatively inexpensive probes for sale. Most homing

Re: [Emc-users] Micro-switch repeatability

On 02/17/2016 04:28 AM, Gregg Eshelman wrote: >> I'm now considering to take an old CD player and move the >> laser-assembly onto several micro-switches at different speeds. The >> laser-assembly is sub-micrometer accurate (CD track-separation runs at >> 1.5...1.6 um) and generally uses a simple

Re: [Emc-users] Micro-switch repeatability

On 2/16/2016 9:40 PM, John Dammeyer wrote: > I believe they only use the home switch to figure out where the end of the > printer is. Once established for page of printing it's not used to > reference until perhaps the next page and probably not even then. From then > on the positioning is based

Re: [Emc-users] Micro-switch repeatability

a slow homing operation on every line. John Dammeyer > -Original Message- > From: Chris Albertson [mailto:albertson.ch...@gmail.com] > Sent: February-16-16 6:34 PM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] Micro-switch repeatability > >

Re: [Emc-users] Micro-switch repeatability

On 2/16/2016 6:47 AM, Bertho Stultiens wrote: > The micro-switches look like they can manage at almost no cost. But then > my curiosity got in my way on how far you actually can go with the > cheapo method. I'm now considering to take an old CD player and move the > laser-assembly onto several

Re: [Emc-users] Micro-switch repeatability

Look at how inkjet printers work. They need to trip a home switch so that each line of sprayed ink lines on to better then 1/1000th of an inch. They use a low cost optical device. There is a slot cut in a plastic block. One one side is a LED on the other a light detector. The look at each

Re: [Emc-users] Micro-switch repeatability

agreed a near home switch and a home switch fanuc called the near hone a 'decel switch' tomp On 02/16/2016 10:42 PM, Kurt M. Sanger wrote: > When we were building high resolution printers we would use an optical > switch looking at a rotary flag in series with a linear switch to define > home.

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 06:46 AM, Bertho Stultiens wrote: > The only alternative is to use a level-based micro-switch. That, > however, will probably make it less accurate. Especially when you move > over it side-ways. The angle of attack is too small with respect to > the travel distance. I use

[Emc-users] Micro-switch repeatability

On 16 February 2016 at 14:46, Bertho Stultiens wrote: > On 02/16/2016 01:38 PM, Nicklas Karlsson wrote: > It seems that the micro-switches are well suited for the purpose, but > I > guess some hard (unbiased) data has yet to be gathered (outside of a > mill). > >>>

Re: [Emc-users] Micro-switch repeatability

When we were building high resolution printers we would use an optical switch looking at a rotary flag in series with a linear switch to define home. We repeated well within ten thousandths of an inch. Kurt Sanger --

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 03:15 PM, TJoseph Powderly wrote: >> I heard rumors here a while ago about micro meter accuracy switch >> but I guess it might be a little bit expensive. > my-com switches, 1um guaranteed. every good german wedm uses them > and high end japanese > my-com > yes expensive paeng maak!

Re: [Emc-users] Micro-switch repeatability

my-com switches, 1um guaranteed. every good german wedm uses them and high end japanese my-com yes expensive paeng maak! but damn accurate tomp On 02/16/2016 02:53 PM, Nicklas Karlsson wrote: > I heard rumors here a while ago about micro meter accuracy switch but I guess > it might be a

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 02:01 PM, Lester Caine wrote: >> Indeed, unless you can crush them. There must be a run-into-the-wall >> protection, as mentioned earlier, to prevent killing your switch. > > The problem on the Taig is while one hits the end stop one end, you come > out of the nut the other ;) But

Re: [Emc-users] Micro-switch repeatability

On 16/02/16 12:26, Bertho Stultiens wrote: >> The alternatives seem to have the same problems of repeatability. Using >> > a hall sensor or optical one will give the same problems. Micro-switches >> > are at least inherently mechanically constrained. > Indeed, unless you can crush them. There must

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 01:38 PM, Nicklas Karlsson wrote: It seems that the micro-switches are well suited for the purpose, but I guess some hard (unbiased) data has yet to be gathered (outside of a mill). >>> The alternatives seem to have the same problems of repeatability. Using >>> a hall

Re: [Emc-users] Micro-switch repeatability

> On 02/16/2016 12:42 PM, Lester Caine wrote: > > On 16/02/16 10:21, Bertho Stultiens wrote: > >> It seems that the micro-switches are well suited for the purpose, but I > >> guess some hard (unbiased) data has yet to be gathered (outside of a mill). > > > > The alternatives seem to have the same

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 12:42 PM, Lester Caine wrote: > On 16/02/16 10:21, Bertho Stultiens wrote: >> It seems that the micro-switches are well suited for the purpose, but I >> guess some hard (unbiased) data has yet to be gathered (outside of a mill). > > The alternatives seem to have the same problems of

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 12:39 PM, Dave Caroline wrote: > I originally searched for a switch with data and a local distributor > had some movement specs of the plunger, I got some but unfortunately > that distributor no longer lists the item. but it is a Patterson V4 > type microswitch, the .tw website of

Re: [Emc-users] Micro-switch repeatability

On 16/02/16 10:21, Bertho Stultiens wrote: > It seems that the micro-switches are well suited for the purpose, but I > guess some hard (unbiased) data has yet to be gathered (outside of a mill). The alternatives seem to have the same problems of repeatability. Using a hall sensor or optical one

Re: [Emc-users] Micro-switch repeatability

I originally searched for a switch with data and a local distributor had some movement specs of the plunger, I got some but unfortunately that distributor no longer lists the item. but it is a Patterson V4 type microswitch, the .tw website of theirs is not easy to read though. One day I might fit

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 07:53 AM, Nicklas Karlsson wrote: > I heard rumors here a while ago about micro meter accuracy switch but > I guess it might be a little bit expensive. Well, yes. The "real" switches which are /specified/ with repeatability values of about 0.005mm are in the order of $200...$300 per

Re: [Emc-users] Micro-switch repeatability

On 2/15/2016 11:53 PM, Nicklas Karlsson wrote: > I heard rumors here a while ago about micro meter accuracy switch but I guess > it might be a little bit expensive. What about the Hall effect or optical sensors that are options with generic electronics parts kits for 3D printers? BTW, Mattel

Re: [Emc-users] Micro-switch repeatability

I heard rumors here a while ago about micro meter accuracy switch but I guess it might be a little bit expensive. On Tue, 16 Feb 2016 07:41:41 +0200 Roland Jollivet wrote: > As others will advise, a slotted disc directly on the stepper is your best > option. It's the

[Emc-users] Micro-switch repeatability

As others will advise, a slotted disc directly on the stepper is your best option. It's the finest resolution you'll achieve for a low cost. Here

Re: [Emc-users] Micro-switch repeatability

On Monday 15 February 2016 21:35:29 TJoseph Powderly wrote: > Gene > an improved home routine would add a solenoid and piping to clean the > switches Ohmygawd. ROTFL. TomP, you kill me with your logic. Of course that would work, but this toy lathe, no matter how much lipstick you put on it, is

Re: [Emc-users] Micro-switch repeatability

most commercial cncs have encoder home morks ( Z phase) and they have what users often miss-call a 'home' switch its really a 'close to home, slow down you fool' switch so the velocities during the home 'stretch' ( between 'nearhome' and home) are always controlled the distance between those

Re: [Emc-users] Micro-switch repeatability

Gene an improved home routine would add a solenoid and piping to clean the switches no more "wheres the dang non-osha gun gone today?" tomp On 02/16/2016 10:11 AM, Gene Heskett wrote: I paint brush or air hose the swarf from in front of it before I command a home,

Re: [Emc-users] Micro-switch repeatability

On Monday 15 February 2016 19:37:43 Bertho Stultiens wrote: > On 02/16/2016 01:16 AM, Len Shelton wrote: > > We in fact see about 2-3 tenths of a thou repeatibility with a slow > > approach on cheap chinese snap switches. > > Just like what others seem to report. > > Is that on direct activation

Re: [Emc-users] Micro-switch repeatability

On Monday 15 February 2016 19:11:10 Jack Coats wrote: > I saw some prox sensors ebay (china trash) that folks on 3D printers > are using for automatic bed leveling compensation. They are about > $2.50/ea delivered, others are $10 if you want a better quality. > > Their repeatability is good,

Re: [Emc-users] Micro-switch repeatability

On Monday 15 February 2016 19:08:34 Bertho Stultiens wrote: > On 02/16/2016 12:57 AM, Gene Heskett wrote: > > I am using some micro-mini roller lever junk I got for 6 bucks a bag > > of 10 from ebay. Repeatability according to my dials is well within > > .001" even with crap switches. Its a

Re: [Emc-users] Micro-switch repeatability

Bertho; I did some tests, plotted the results, etc, at: http://cnc-for-model-engineers.blogspot.ca/2015/06/home-switch-repeatability.html I think my major issue was the mounting for my dial indicator, and if you do read the article, I did some tests with my new mill, and results are the same or

Re: [Emc-users] Micro-switch repeatability

I saw some prox sensors ebay (china trash) that folks on 3D printers are using for automatic bed leveling compensation. They are about $2.50/ea delivered, others are $10 if you want a better quality. Their repeatability is good, If using switches, please check the brand. Microswitch and

Re: [Emc-users] Micro-switch repeatability

I also remember someone, could have been at reprap.org or cncrouterparts.com, doing repeatability tests, and getting similar surprisingly consistent results with cheap switches. On Mon, Feb 15, 2016 at 5:04 PM, Len Shelton wrote: > We don't use levers, we activate the

Re: [Emc-users] Micro-switch repeatability

We don't use levers, we activate the plungers directly. The key is to design the switch mount such that a physical stop would prevent wrecking the plastic switch on a rapid jogs ooops. >Len On 2/15/2016 6:37 PM, Bertho Stultiens wrote: > On 02/16/2016 01:16 AM, Len Shelton wrote: >> We in

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 01:16 AM, Len Shelton wrote: > We in fact see about 2-3 tenths of a thou repeatibility with a slow > approach on cheap chinese snap switches. Just like what others seem to report. Is that on direct activation or using an positional offset on a lever? Using a lever seems like

Re: [Emc-users] Micro-switch repeatability

We in fact see about 2-3 tenths of a thou repeatibility with a slow approach on cheap chinese snap switches. >Len On 2/15/2016 6:08 PM, Bertho Stultiens wrote: > On 02/16/2016 12:57 AM, Gene Heskett wrote: >> I am using some micro-mini roller lever junk I got for 6 bucks a bag of >> 10 from

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 12:57 AM, Gene Heskett wrote: > I am using some micro-mini roller lever junk I got for 6 bucks a bag of > 10 from ebay. Repeatability according to my dials is well within .001" > even with crap switches. Its a "dry' circuit, so as long as the > contacts are clean, there's very

Re: [Emc-users] Micro-switch repeatability

On 02/16/2016 12:53 AM, Dave Cole wrote: >> Has anyone numbers on the repeatability of "normal" >> micro-switches? >> >> Micro-switches are (relatively) cheap and mostly not too shabby, >> but I have a not seen any hard data on repeatability (other than >> datasheets saying that they are made for

Re: [Emc-users] Micro-switch repeatability

On Monday 15 February 2016 18:44:00 Bertho Stultiens wrote: > Hi, > > I'm looking for an on-the-cheap way to do reasonable homing. Usual > switches for the purpose cost a lot. The machine only has a > repeatability of 0.02mm, so it may just be a waste to use too accurate > (expensive) switches. >

Re: [Emc-users] Micro-switch repeatability

If you have a marker pulse on an encoder you can use a cheap home switch and back off to the marker pulse. Dave On 2/15/2016 6:44 PM, Bertho Stultiens wrote: > Hi, > > I'm looking for an on-the-cheap way to do reasonable homing. Usual > switches for the purpose cost a lot. The machine only has

[Emc-users] Micro-switch repeatability

Hi, I'm looking for an on-the-cheap way to do reasonable homing. Usual switches for the purpose cost a lot. The machine only has a repeatability of 0.02mm, so it may just be a waste to use too accurate (expensive) switches. Has anyone numbers on the repeatability of "normal" micro-switches?