Bantam Tools Blog

Otherplan Public Beta 0.27: Cutting PCB Milling Time

Posted by Ezra Spier on Apr 28, 2016 9:22:15 AM
Find me on:

Screen_Shot_2016-04-28_at_8.49.15_AM.pngOtherplan 0.27 set up to mill an Arduino Pro Mini with 30º Engraving Bit and 1/32 inch Flat End Mill

This month’s Otherplan release improves one of the most important aspects of the PCB milling process: speed! Get Otherplan Public Beta 0.27 for Windows and Mac now or read on for all the details.

Download Now

We know that it’s important to have PCBs as quickly as possible, and we’ve been exploring a number of ways to increase milling throughput without sacrificing quality or precision. Otherplan 0.27 has two new features that will significantly cut PCB milling time for most users: optimized feeds and speeds as well as engraving bit isolation milling.

Optimized Feeds and Speeds for FR-1

Over the past few months, we’ve been researching the feeds and speeds Otherplan uses when milling FR-1. Feeds and speeds are important because they specify exactly how quickly the Othermill mills out PCBs. When we first created Otherplan’s defaults, we chose conservative values in an attempt to minimize the risk of tool breakage.

  Classic Feeds and Speeds Optimized Feeds and Speeds
Feed Rate 360 mm/min 1500 mm/min (4x faster)
Plunge Rate 30 mm/min 380 mm/min (12x faster)
Spindle Speed 12,000 RPM 16,400 RPM
Max. Pass Depth 0.15 mm 0.15 mm

Classic vs. Optimized Speeds and Feeds for 1/32" Flat End Mill

After a great deal of testing, we’re releasing new defaults that are substantially faster. These optimized feeds and speeds are in our FR-1 Material Guide and have been used internally and by customers for some time. We're now confident that these faster speeds and feeds are ready for everyone. To get these new feeds and speeds, just upgrade to Otherplan 0.27, or use BitBreaker Mode in Otherplan 0.14.7 to configure them yourself. You’ll need a V2 Othermill to use these new feeds and speeds.

Because these speeds and feeds are faster, it’s more important than ever to ensure that your FR-1 is securely attached to the Othermill before milling. If you need a refresher, read our support guide on how to use double-sided tape. And if you haven’t yet, we recommend picking up a roll of Nitto tape for best results.

Engraving Bit Isolation Milling

Ever since we released the Othermill, we’ve recommended using flat end mills to machine PCBs. Flat end mills are precise and effective, but they have limitations — particularly when PCBs have very small features. If you’ve ever used a 1/64" or 1/100" end mill, you’ve probably experienced long milling times because increasing the milling speeds could easily cause broken bits.

Flat End Mill Illustration Engraving Bit Illustration
Flat End Mill vs. Engraving Bit

We’re excited to share a new alternative approach to PCB milling: engraving bit isolation milling. Engraving bits are tapered milling tools. Although the diameter of these tools can be 1/100" and smaller, their tapered shape results in a tool that is significantly stronger than an end mill. This increased strength of the engraving bit means that they can mill through FR-1 at a much faster speed. The end result? Precise PCBs in record time.

In Otherplan 0.27, simply select a 30º or 80º engraving bit, and Otherplan will automatically select an appropriate trace depth and fast feeds and speeds. Because they're tapered, engraving bits can only be used to mill traces, so make sure to select an end mill when you're milling holes or outlines.

For best results, we recommend using a 30º engraving bit, now available in OMC’s online store. We tested many different bits before choosing this one, and we found it to be the best balance of precision, tool life, quality, and cost. If you have one of our 80º bits, it'll work as well.

Finally, engraving bit isolation milling does have tradeoffs, so make sure to read up on the process in our new support guide.

Other Updates

In every Otherplan release, we aim to fix bugs and make tweaks to improve your experience. This month, we’ve:

  • Fixed a bug that sometimes caused the Othermill to be stuck in the "Initializing" state after powering on with the emergency stop button engaged.
  • Fixed a bug that hid PCB pads in some .brd files.
  • Greatly improved USB communications reliability on Windows 10.
  • Updated to version 5.6 of Qt, the cross-platform user interface toolkit used by Otherplan, which contains a large number of bug fixes and improvements.

We hope that the throughput improvements in this release save you time — but we’re just getting started. As always, we’re excited to hear your feedback. Please don’t hesitate to contact us if you have any to share.

Our sales team is also standing by if you have questions about how the Othermill might accelerate your in-house prototyping. Just follow this link to request a consultation.

Topics: Circuit Boards, Software, Otherplan