I was milling a Zr framework bridge on Friday and about 10 minutes into milling I get an alert that the spindle has crashed (error 102E). The bridge was placed relatively close to the material holder and had to be angled in order to fit into the 14mm puck.
I walked over to see the 2mm burr had made contact and started to cut into the clamp when the mill shut down. I called CAP before doing anything to make sure the spindle was OK to use, but all I really got was "I've never seen that error before". Tried remilling with the burr that was in there but I quickly realized that was toast. Too bad it was a pretty new diamond coated burr.
Started a new job with a new puck and new burr, placed the bridge as far as I could from the clamp and it milled fine.
Since we've only been milling for about 6 months, I figured I would ask everyone if this is something that happens from time to time? Doesn't SUM3d do a collision check before starting the mill job? Any advice to avoid anything like this in the future?
Thanks in advance for all of your advice!
Hi Erykd1,
I'm from the USA office for CIMsystem - the developers of the SUM3D Dental CAM.
Collisions are not a typical occurrence. Just to prevent any miscommunication - a collision is not a cut and dry issue related to the CAM software. Furthermore, SUM3D uses the clamp during the collision protection service and we do also use safe working areas as long as it has been enabled by the re-seller in the clamp file. I can verify with CAP but I do believe they are using this protection boundary in their current clamp files. Regardless of the CAM you're using, there's quite a few things that could cause collisions. Just to name a few:
- Loose chuck = Grip on tool is not adequate which can lead to the tool slipping and the machine can subsequently lose position due to the taper on the tool shanking out on part / material.
- Calibration of machine being out.
- Lack of adequate air pressure. This can lead to excess material buildup in the cavity during the roughing stage which can cause the tool to slip and just as in the first scenario cause unexpected collisions.
- Using a non-collared disc yet selecting a collared stock in the CAM - This can cause a collision during the roughing stage since the material is offset different for collared versus non-collared material.
There are many more scenarios to mention that could cause the behavior but when you have any incident regarding the mill, my advice is to do the following before anything else:
- Take pictures - before removing the tool, take pictures of how it's being held in the spindle, take pictures of the milled part, take pictures of any obvious areas on the material / clamp where collisions may have occurred. This is invaluable information when troubleshooting that will allow your reseller to re-trace the steps leading up to the incident.
- Do not change anything in your original .CAM File - This includes recalculating, moving parts / support pins, etc. This is because we want to preserve all of the original data that was generated in the initial CAM File so this can be passed on to your re-seller and if needed, on to CIMsystem (Software Developer)
- If you have to make a change due to production needs, first make a copy of the original file, open it using the open file dialogue and work with the copy. In doing this, you've preserved all of the original conditions of how you nested / calculated the original file and also the original toolpaths that were generated.
- Check your simulation - When an issue occurs, generally you will be able to see this in the simulation. If not, the likelihood that the CAM was the culprit of a blatant collision is very low. This is not always the case as mentioned above, the simulation shows the instructions that were sent to the machine but does not take other factors into account:
- Physical Tools - If you place different physical tools in the machine for instance, the extension could be shorter however the CAM has no way of knowing this so a collision could occur.
- If Air Pressure is not adequate you can have tool slippage or tool breakage that would otherwise not be seen in the simulation.
- And the list goes on.
The main take-away from this post is that there are so many different factors that can lead to a collision, so it's best to know all of the factors before drawing conclusions. Regarding your particular issue, if you'd like to troubleshoot - you can contact me directly here:
[email protected] You can also message me your contact information if you'd like and I can give you a call Monday morning to discuss further.
We open a ticket for you and can go through the proper troubleshooting steps to help determine as closely as possible what actually happened and how it can be prevented in the future. It's important that we have the original un-modified .CAM File so we can examine the toolpaths generated as a first step. If you have the original .PRN File that the collision occurred with, that would be helpful as well.
Best Regards,
Mike Webb