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Leadhead
26-09-2013, 08:52 PM
Could anyone recommend a commercial budget/hobby priced tool pre-setter for a CNC mill please. Done the bay!!

GEOFFREY
27-09-2013, 09:59 AM
Most commercial pcb machines use tools pre set to a fixed length but this relies on the cutters of various diameters all having the same overall length and shaft diameter. When using tools withe different diameters and lengths I am not aware of any low priced items, but feel sure that it would be possible to make one. It would mean getting your (or someone elses') thinking cap on. G.

Leadhead
27-09-2013, 10:18 AM
Yes - I have a scheme to use a small linear bearing and a small piece of ground shaft to suit. Acting on an old Mercer clock. But as usual not getting "round tuit"
So was looking for any expedient.
I run on an ER32 collet set and have to change tools (and collets) at the tool call. So have to set height on each occasion, since there is no reliable backstop position for most of my tooling. - Unless anyone has a method to share??

Ulsterman
27-09-2013, 07:16 PM
Put two V-blocks on there side on a surface plate and height guage
After you put all the absolute values in for the tools and checked clearances tool change is easy

Take tool out and to the height guage ---zero off the tool and then replace -------use the height guage and find out new tool value as incramental
orginal value would be zero and new offsett would be minus the new value like -.01 or plus 0.5

This was the old and fast way of making sure the new tool cut to the same depth as the last one

JAZZCNC
27-09-2013, 07:39 PM
Without tool holders that locate to set register on the spindle then ER collets are not reliable due to there nature of pulling in when tightened having no set reliable register.

What control software do you use.?

Leadhead
28-09-2013, 07:44 AM
Running on Mach3.

JAZZCNC
28-09-2013, 10:56 AM
Running on Mach3.

Well then what you need is to use a touch plate connected to a spare input to measure tool offset and use Gerry's 2010 screen set with auto tool changer option.
If you haven't seen or heard of it before what you have is fixed plate on bed or machine and a Floating plate on a wire which share same input.
When setting first tool you use floating plate on material surface and touch first tool off it and Software saves this offset.
Then when you change next tool it shoots off to fixed plate touches off and makes note off the offset of new tool then deducts 1st tool offset with 2nd offset and then carrys on it's merry way. . . . . All you do is change tool and click cycle start it does the rest. . . . Simplzzz

Also the floating plate can be used as a simple tool height setter for single tool jobs. Makes setting tool height literally 20s job and very very accurate.

Also the screen set has many probe routines that are very useful and you use the floating plate for this also.

There's many benefits over Mach's standard 1024 screen one being much larger tool path screen . . . . Check it out here. The CNC Woodworker - Mach3 2010 (http://home.comcast.net/~cncwoodworker/2010.html)

If you don't want to change from standard screen set then it's still do able but will need a few macro's and buttons adding or modifying. Obviously to take this route you need to know macros and how to modify screen sets which you may not know how but get in touch if you want to go this way I'll modify it for you.