I think the problem with proxies is that any chips in the probe path is going to affect this distance, quite lilely flood coolant situations.
The mechanical switches on CNC machines however, have a slope on the switch and are really difficult to press in with your finger. This makes sure that any junk gets wiped off during the homing process. As can be seen in this image, they often have two or three switches built in; https://za.pinterest.com/pin/531424824774161839/ This allows you to use actuating flags of different lengths to implement; - axis home position - overtravel limit - Estop limit Roland On Thu, 4 Nov 2021 at 10:20, Chris Albertson <albertson.ch...@gmail.com> wrote: > I bought some of the proximity detectors for my 3D printer to measure the > bed. I tested them on my mill by moving them untillthey tripped, backing > off and doing it again to see how repeatable they are. Even the cheap > no-=brand unit where as good as my ability to measure them. Set up a test > using a dial indicator. > > The absolute trip point was some random distance, all you care about is how > repeatable they are. > > The one I liked is mounted in M12x1 threads. I bought am M12x1 tap to make > a mounting block > > The usual connector is called an "Aviation Plug". they come in different > diameters and with different amounts of pins. The smaller size is enough > for signals and the larger ones can handle motor current. They come in > different quality levels too. The cheap Chinese ones are "good enough" but > the American ones are precision made and have rubber gaskets. Prices are > about $3.50 for the cheap ones (on eBay or Amazon) and about $35 for the > best quality ones (at Mc Master Carr and the like). > > The cheap plugs are made of something like chromed zinc and look cheap but > work surprisingly well. The best one are made of machined an > green-primmered aluminum and have the quality you'd expect for an $80 per > mating par part. They are also sold with engineering-grade plastic > housing > > On Wed, Nov 3, 2021 at 10:01 PM Ralph Stirling < > ralph.stirl...@wallawalla.edu> wrote: > > > I have finally started stripping out the control cabinet on my cnc mill > in > > preparation for my retrofit. The brushed servos and mechanical limit and > > home switches were wired up with crimped "bullet" quick connect pins. > I'm > > replacing the servos with brushless servos, and am considering replacing > > the mechanical switches with inductive prox sensors (pnp, nc type). All > > the old wires are sticky with coolant and metal chips. > > > > So, I am interested to hear what other lcnc retrofitters have found works > > well for modest priced coolant proof connectors (3 or 4 pin), and > opinions > > on cheap Chinese prox sensors (since the name brand ones are so > expensive, > > even on ebay). An example is: > > > https://www.ebay.com/itm/US-5Pcs-NC-PNP-LJ18A3-8-Z-AY-Inductive-Proximity-Sensor-Switch-DC6V-36V-/143861840692 > > > > Photos (rather unorganized) of the retrofit are at: > > https://photos.app.goo.gl/yBSRVf3QAVUK39PC7 > > > > Thanks, > > -- Ralph > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > -- > > Chris Albertson > Redondo Beach, California > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
