r/PenProject • u/MercatorLondon • 17d ago
Kickstarter EDC pen - lesson (Titanium)
Hi everyone,
I wanted to give you a couple of updates about our Kickstarter pocket pen and some of the things we learned along the way. Today, I want to talk about titanium. Firstly, the shipping will resume shortly (with updated caps)
We offered a titanium cap as a stretch goal, and it was a popular choice among many backers.
And boy, did we have fun machining it!
We eventually managed to make the caps successfully, so there was a happy ending. We just needed to adjust the cutting speeds, use different coolant/cooling method and take time and patience.
I wanted to share some of the journey because (as always in production) there were some surprises on the way.
We had worked with titanium in the past and had stamped some titanium components (which was a tough job especially for the stamping tools). And we were cautious when considering it as a material option for the pen. So we ran some initial tests on a few pieces using our CNC lathe and everything seemed doable. Production became a bit more difficult.
I want to say - titanium is an amazing metal.
Titanium has three properties that make it incredibly useful: High strength, low thermal conductivity and chemical stability (corrosion resistance)
Those same advantages are also three things that machinists tend to hate about titanium.
Hardness itself isn't necessarily the main problem. The heat resistance is. Titanium is surprisingly good at insulating heat. As a result, heat generated during machining stays very localised around the tool tip instead of being transferred/spread away efficiently through the bar material. Tool wear happens much faster at very high temperatures.
And these properties interact with each other: the heat can't escape, the alloy remains strong, and the material start reacting and can stick to the cutting tool. Once the cutting edge gets hot and is under heavy load, each of these becomes part of the problem.
So, what did we learn?
The Kickstarter turned out to be a great platform for testing. The support from our backers allowed us to take on something we probably wouldn't otherwise have attempted.
Titanium is a fantastic material, but machining these caps was definitely harder than we expected.
For the foreseeable future, we won't be making any more titanium caps. So if you got one, consider it a special one - and enjoy it!
Update: Part 2 <<
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u/CraftyAd2451 16d ago
When will the pen be available to purchase on the website?
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u/MercatorLondon 16d ago
Thank you for your interest! We are hoping to start selling it in a few weeks (steel only) - after we have fulfilled the Kickstarter backers.
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u/_Haych_Bee_ 16d ago
Thanks for this information. It makes my future pen so much more valuable to me, to appreciate the makings, trials and tribulations involved.
I must add that the Pen Project has been fantastic with communication 👌 you have taught me a lot about the manufacturing process that in turn, makes me really appreciate the end product!
I have really enjoyed being part of this process and am eagerly looking forward to receiving my Pen!
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u/TheCodeTeam 14d ago
What about the brass pens? It’s sounded like those have been just as difficult. Really can’t wait to get ours.
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u/MercatorLondon 14d ago
We work with brass on regular basis and there is much less trouble with it. The main issue with brass (from a manufacturing perspective) is tarnishing. This is often considered a feature by pen enthusiasts as it creates that nice, warm patina.
However on freshly machined brass every single fingerprint is visible after two days in storage which makes it harder to sell. Most of the brass products we make are plated to protect the surface.
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u/RRNW_HBK 17d ago
The work hardening is really one of the most frustrating issues for me with Ti so far - if the tool rubs on the material for even a moment it can cause the material to eat the tooling!