# Initial tool position a crash? **URL:** \ **Category:** CAM\ **Created:** [January 14, 2026, 2:01am UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902 "2026-01-14T02:01:36Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![meddesign](https://forum.grid.space/letter_avatar_proxy/v4/letter/m/d6d6ee/32.png) [@meddesign](https://forum.grid.space/u/meddesign)\ **Post date:** [January 14, 2026, 2:01am UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/1 "2026-01-14T02:01:37Z")
I am trying to machine the top portion of this fitting…the stock is oversize and my thought was to have the z top and origin at the oversize dimension rather than using numerous level operations to get the stock to the right size. Animation puts the initial position of the tool at -2.7mm which is the top of the fitting not the top of the stock. This shows in the first line of the .nc gcode before it retracts to start cutting at the stock top. using the Kiri:Moto Dev tool [workspace\_BOTT\_LUG (2).kmz](https://forum.grid.space/uploads/short-url/HjhspqD2yPtlVjqh4rqXROCXEM.kmz) (556.8 KB) ---
**Author:** ![stewart](https://forum.grid.space/user_avatar/forum.grid.space/stewart/32/21_2.png) [@stewart](https://forum.grid.space/u/stewart)\ **Post date:** [January 14, 2026, 3:02am UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/2 "2026-01-14T03:02:40Z")
you are correct. it did not occur to me to set the z top above the stock. the first move is to stock top + z clearance. so the only way to achieve this (until i fix it) is to set z clearance greater than z top. ---
**Author:** ![stewart](https://forum.grid.space/user_avatar/forum.grid.space/stewart/32/21_2.png) [@stewart](https://forum.grid.space/u/stewart)\ **Post date:** [January 14, 2026, 3:09am UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/3 "2026-01-14T03:09:04Z")
I pushed a fix to the dev server. lmk if it works for you ---
**Author:** ![meddesign](https://forum.grid.space/letter_avatar_proxy/v4/letter/m/d6d6ee/32.png) [@meddesign](https://forum.grid.space/u/meddesign)\ **Post date:** [January 14, 2026, 2:25pm UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/4 "2026-01-14T14:25:30Z")
[workspace\_BOTT\_LUG (4).kmz](https://forum.grid.space/uploads/short-url/pREZW45KfMUGMbqviUUFWmUFLph.kmz) (507.5 KB) no joy….changed step down to speed up but still first step below top of stock. (dev server. lmk???) ---
**Author:** ![meddesign](https://forum.grid.space/letter_avatar_proxy/v4/letter/m/d6d6ee/32.png) [@meddesign](https://forum.grid.space/u/meddesign)\ **Post date:** [January 14, 2026, 2:26pm UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/5 "2026-01-14T14:26:40Z")
> [@stewart](#): > > s to set z clearance greater than z top. s to set z clearance greater than z top. [workspace\_BOTT\_LUG (3).kmz](https://forum.grid.space/uploads/short-url/ziD8TvPMEZ9PuApT1aZGXUhjS05.kmz) (518.0 KB) second move a crash ---
**Author:** ![stewart](https://forum.grid.space/user_avatar/forum.grid.space/stewart/32/21_2.png) [@stewart](https://forum.grid.space/u/stewart)\ **Post date:** [January 14, 2026, 2:56pm UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/6 "2026-01-14T14:56:43Z")
I found the issue. when `z top` is set _above_ the top of stock, the resulting gcode is offset by the distance between the two. the preview does not reflect this, so it is in error. working on a solution. thanks for the workspaces. ---
**Author:** ![stewart](https://forum.grid.space/user_avatar/forum.grid.space/stewart/32/21_2.png) [@stewart](https://forum.grid.space/u/stewart)\ **Post date:** [January 14, 2026, 3:34pm UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/7 "2026-01-14T15:34:56Z")
a few bugs (some visual) fixed and pushed to the [dev server](https://dev.grid.space/kiri). this workspace uses a negative level value to clear the top. I need to fully audio origins which are above the stock. this has odd consequences. [workspace\_BOTT\_LUG\_level.kmz](https://forum.grid.space/uploads/short-url/iudxwtTMAioWFJ2JuamH15TOeVy.kmz) (795.4 KB) ---
**Author:** ![stewart](https://forum.grid.space/user_avatar/forum.grid.space/stewart/32/21_2.png) [@stewart](https://forum.grid.space/u/stewart)\ **Post date:** [January 14, 2026, 3:50pm UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/8 "2026-01-14T15:50:50Z")
imo, the right way to do this is to increase the stock Z offset and use Z anchor bottom. this projects the stock (cuttable area) above the part. this is what Kiri expects. in your previous attempts you’re trying to use the origin and Z top to trick Kiri into treating the air above the part as a millable area. but this is not how Kiri is designed. routing and collision detection are all about traveling through the stock and/or through the part. attached is a workspace that alters the stock and the object position in the stock rather than messing with origin and z top. [workspace\_BOTT\_LUG\_corrected.kmz](https://forum.grid.space/uploads/short-url/8ZPNfBZSqXkiwlg4xrqcJji2fnm.kmz) (1.3 MB) ---
**Author:** ![meddesign](https://forum.grid.space/letter_avatar_proxy/v4/letter/m/d6d6ee/32.png) [@meddesign](https://forum.grid.space/u/meddesign)\ **Post date:** [January 14, 2026, 4:24pm UTC](https://forum.grid.space/t/initial-tool-position-a-crash/2902/9 "2026-01-14T16:24:46Z")
now I know what z anchor means…works.