Thread: Cheap Tool Length Sensor Options
-
13-02-2023 #11
For what it's worth here are some pics of one I made years back for my Novamill.
Basically laminated from a MS block with an inset magnet, then layers of 12mm epoxy fibreglass (could be e.g. Corian). There is a machined cavity inside which contains a stainless steel slug at the botton (insulated from the base), then a strong spring, then a 12mm square carbide insert as a hard anvil. Most of the layers are glued with epoxy but the top is bolted on to allow assembly. The slug has a hole drilled from the side for a 4mm banana plug to connect to the probe input. It fits to the table with the magnet, and the top face of the anvil is measured at 38.84mm above the table surface which is input as the setting plate thickness. As the Novamill table is small I generally just place this for setting the tool then take it away, with a bigger table it could be left in one place. The spring has a few mm free travel to reduce the consequences of a tool crash. Of course it depends on the tool being grounded. Total cost negligible as made from the scrap box.
On my lathe I have a rather different system to do an equivalent job which is to find the end of the stock in the chuck and zero the z axis. That's another story, it still relies on electrical contact between tool and work but senses that magnetically.Last edited by JohnHaine; 13-02-2023 at 06:46 PM.
-
18-02-2023 #12
Thanks John, nice solution for a real engineer. As a woodworker I need to buy or assemble from purchasable parts.
Coincidentally I noticed from another reply you are based in Cambridge UK, like me.
-
18-02-2023 #13
FWIW, My probing routine requires me to touch the plate to the tool to initiate the process. I touch it against the tool and then it pauses for a few seconds, then the machine proceeds to move downwards. This, hopefully checks that there is a working connection.
-
18-02-2023 #14
I'd always recommend testing the probe prior to any automated probing routines.
If you're manually changing a tool, then you're already at it, so for all the time it takes to trigger the probe/touch the plate against the tool, it ensures things are working, and eliminates the risk of a broken wire, or more likely, you've forgotten to plug it inAvoiding the rubbish customer service from AluminiumWarehouse since July '13.
-
20-02-2023 #15
If you fit a "loop back" connection within the probe plug, you can detect if the probe is(n't) plugged in and inhibit probing moves. Requires an additional input but equally it reduces the risk of a crash. Some probes also have a secondary (overtravel) switch that you can wire into the e-stop circuit in case the probe connection doesn't work.
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
Tool height sensor.
By Ollie78 in forum General DiscussionReplies: 10Last Post: 27-06-2019, 09:32 PM -
WinNc Sinumerik 810D/840D can't accept tool length compensation
By Maxiscnc in forum Siemens (Sinumerik)Replies: 5Last Post: 25-02-2019, 01:45 PM -
How to use the tool height probe sensor?
By jhonansaro in forum Laser Machines & BuildingReplies: 4Last Post: 04-05-2018, 09:21 AM -
Relationship between Guide rail length and ballscrew length
By CharlieRam in forum Rails, Guideways & BearingsReplies: 6Last Post: 11-07-2014, 11:37 PM -
Z AXIS, big tex blue screen and auto tool sensor Problems
By Tomnewry in forum Artsoft Mach (3 & 4)Replies: 11Last Post: 01-01-2014, 09:01 PM
Bookmarks