# Parts coming in under sized **URL:** \ **Category:** General Chat\ **Created:** [May 23, 2026, 9:06pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178 "2026-05-23T21:06:48Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Bstanga](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/bstanga/32/791_2.png) [@Bstanga](https://forum.avidcnc.com/u/Bstanga)\ **Post date:** [May 23, 2026, 9:06pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/1 "2026-05-23T21:06:48Z")
So I am working on some trigger group parts, If I 3d print the stl it comes out perfect. When I import into aspire it shows the correct radius ( this is a rotary job) however over the last day or 2 these parts come in about 20 thou too small. I have increased the model by 20 thou but still under on the finish toolpath. the roughing looks to be correct. On the roughing I have it set 0.0 allowance same as finish. However the finish always seems to remove material where it should be at the correct dia. ![Screenshot 2026-05-23 155258](https://canada1.discourse-cdn.com/flex027/uploads/avidcnc/original/2X/f/f54e2b316f625800aaf15d0d50d862e73c307809.jpeg) ---
**Author:** ![Bstanga](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/bstanga/32/791_2.png) [@Bstanga](https://forum.avidcnc.com/u/Bstanga)\ **Post date:** [May 23, 2026, 9:12pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/2 "2026-05-23T21:12:18Z")
Maybe I should try this in f360, but I may have to pay to use the rotary functions. I have the free version, but haven’t used it in years. Can anyone confirm if I have to pay to subscribe for rotary. ---
**Author:** ![PaulC](https://avatars.discourse-cdn.com/v4/letter/p/e9a140/32.png) [@PaulC](https://forum.avidcnc.com/u/PaulC)\ **Post date:** [May 23, 2026, 11:33pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/3 "2026-05-23T23:33:23Z")
Yes you have to pay for rotary, first tier gets you atc and limited rotary, second tier gets better rotary. You can get a free trial to see what you need. Some people go the token route instead of the yearly subscription. I use Desk Proto 8.0 for my rotary, or at least I did when I was using mach 3. I have not gotten the rotary up and running on my new EX system so I have no experience with the Desk Proto post processor for the EX. As for your trouble with under sized parts I would start by looking at the minimum Z on the two passes. After that I would make sure that both of them are centered on the rotary axis X or Y equals 0. Then I would make sure that my tool wasn’t slipping, or if you are changing tools between passes that you got the tool length right. ---
**Author:** ![jjneeb](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/jjneeb/32/244_2.png) [@jjneeb](https://forum.avidcnc.com/u/jjneeb)\ **Post date:** [May 24, 2026, 10:57pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/4 "2026-05-24T22:57:05Z")
I don’t have any ideas for you, but I am looking forward to seeing how these parts come out. Are you cutting them in steel? ---
**Author:** ![PaulC](https://avatars.discourse-cdn.com/v4/letter/p/e9a140/32.png) [@PaulC](https://forum.avidcnc.com/u/PaulC)\ **Post date:** [May 24, 2026, 11:11pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/5 "2026-05-24T23:11:39Z")
If you run the roughing pass twice (no finish pass), does the tool touch the material? ---
**Author:** ![Bstanga](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/bstanga/32/791_2.png) [@Bstanga](https://forum.avidcnc.com/u/Bstanga)\ **Post date:** [May 25, 2026, 1:53am UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/6 "2026-05-25T01:53:02Z")
I do have deskproto, never used it. ---
**Author:** ![Bstanga](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/bstanga/32/791_2.png) [@Bstanga](https://forum.avidcnc.com/u/Bstanga)\ **Post date:** [May 25, 2026, 1:59am UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/7 "2026-05-25T01:59:00Z")
Brass, I paid $80 for 3 ft , can you upload a video to the forum here, I’ll show you what the part does. ---
**Author:** ![jjneeb](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/jjneeb/32/244_2.png) [@jjneeb](https://forum.avidcnc.com/u/jjneeb)\ **Post date:** [May 25, 2026, 3:18am UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/8 "2026-05-25T03:18:38Z")
> [@Bstanga](#): > > can you upload a video to the forum here, I think you can just paste in a video file. If not, you can definitely paste in a youtube link. ---
**Author:** ![greg.obj](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/greg.obj/32/2807_2.png) [@greg.obj](https://forum.avidcnc.com/u/greg.obj)\ **Post date:** [May 25, 2026, 3:42am UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/9 "2026-05-25T03:42:38Z")
.02" is definitely within the realm of how much the frame can expand/contract due to temperature - have you tried recalibrating your rotary WCS then running the job? ---
**Author:** ![Bstanga](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/bstanga/32/791_2.png) [@Bstanga](https://forum.avidcnc.com/u/Bstanga)\ **Post date:** [May 25, 2026, 7:06pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/10 "2026-05-25T19:06:07Z")
No but that is a good idea it’s been a while since I recalibrated the rotary ---
**Author:** ![Bstanga](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/bstanga/32/791_2.png) [@Bstanga](https://forum.avidcnc.com/u/Bstanga)\ **Post date:** [May 25, 2026, 7:07pm UTC](https://forum.avidcnc.com/t/parts-coming-in-under-sized/6178/11 "2026-05-25T19:07:00Z")
That would be a really good test to do as well I’ll try that