DAMMERR.COM

03/13/2026

Inventory

01/30/2026

I don't know if you know my buddy Bruce Hildenbrand, climber, former professional cyclist and journalist writing for Outside, Cycling and Climbing. He called me last night from Stanford Hospital. On Wednesday afternoon he was riding his bike near his home while testing my cycling gradient meter and got hit by a dump truck! Broken wrist, broken clavicle, cracked vertebrae and a badly broken femur. He's had some nasty bike crashes over the years, he got hit by a car in France about 10 years ago and had to charter an AirMed flight to get to better surgeons in California.

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01/15/2026

This is totally unrelated to hammers, but here's a nerdy rabbit hole I've gone down...

I love to ride my bike, and I also love playing with data. My Garmin bike computer displays gradient, but it's frustratingly inaccurate. The problem? It relies on GPS (slow, only accurate to maybe 10 meters) and a barometric altimeter (imprecise and unstable).

So I thought: why not measure the tilt of the bicycle frame directly?
I spent a significant part of my career doing instrumentation and measurement, so I started experimenting with tilt meters. A simple bubble level won't work—any acceleration when you speed up or brake throws it off completely.

First, I tried a tiny Bluetooth tilt meter taped to my top tube (WIT Motion WT9011DCL—under $20 from China). Super accurate and stable, but I couldn't keep my phone awake on long rides to watch the data in real time.

So I built my own standalone display and logger with a touchscreen, using a Waveshare ESP32-S3 development board (about $30). Here's the thing: I don't write code. The only programming class I ever took was 50 years ago using punch cards. But with AI help, I wrote and compiled 1,000 lines of code to make this work.

The device measures slope using gyroscopes with corrections from accelerometers. The gyros measure rotation rate, which you integrate over time—but integration amplifies errors. That's where Kalman filtering comes in, a probability-based method for correcting telemetry that's completely new to me and absolutely fascinating.

I've got it working and logging data to a micro SD card. There's still snow and black ice everywhere, so no road test yet, but bench testing looks great.

The hardware cost: $30-50. The software, based on my invested time: roughly a million dollars. Software always costs more than hardware.

01/08/2026

"Give a small boy a hammer and everything he meets has to be pounded."

Hammers with stainless steel tube on the handles. A mix of hickory and black locust handles. A few thin picks, some thicker.

12/07/2025

8/4 black locust slabs for handles.

09/30/2025

Nothing about hammers in this post. Avoiding tourists can be pretty easy, go in the off season, get away from your car and maybe seek the overlooked near to major attractions. Yosemite valley is spectacular and a unique place on the planet with the most worthy rock climbs on the planet but I don't really like going there. I'd rather visit the less travelled parts of the Sierra Nevada where things may be a bit less spectacular but there are a tiny fraction of the people and you will be more likely to encounter adventure. Also, if you get away from your car, you will be away from 90% of the people. If you step off the trail, you will lose 90% of the people who got out of their cars. Climb an easy route on a lesser known peak near a known one and you won't see anybody.

08/22/2025

Shannon Joslin is the Yosemite ranger who was recently fired for helping to hang a giant pride flag off El Capitan. Shannon has authored climbing guidebooks which you can buy here:
https://www.yosemitevalleybouldering.com/
https://www.goldenstatebouldering.com/

As a PhD biologist, Shannon worked with what they referred to as the "Big Wall Bat Program." Sadly this has nothing to do with Warren Harding.

Shannon contacted me over a year ago looking for a big wall hammer for the Big Wall Bat program saying that they would pay for a hammer using their own personal funds. I sent a hammer gratis and received an email saying "I got the hammer. It is beautiful and we are lucky to have it for our program! Thank you so much."

Although we haven't met face to face, Shannon seems real nice and is certainly a real climber.

https://www.nationalgeographic.com/animals/article/to-save-yosemites-bats-scientists-need-help-finding-them

A deadly fungus has killed millions of bats across North America over the past decade. To protect the bats in the park, biologists first need to document the many places they roost.

08/03/2025

This is what the nickel electroplating on the handle steel tube looks like, not as garish as chrome and should hold up better than the cold bluing I used on previous hammers. The handle was submerged in boiled linseed oil inside a vacuum chamber so the wood is deep impregnated with the oil which will polymerize with time.

04/27/2025

I've been blackening the steel reinforcing tube on the handles with black iron oxide simply by cleaning it and applying a solution. It isn't a very durable finish and I'm thinking of trying to make some hammers with electroplated steel tubes. I'm trying to figure out what would look best.

copper
brass
bronze
nickel
cadmium
black nickel
Silver
Gold

Some are easier than others, some processes are more toxic and some are cheaper.

It is possible to plate the heads too but cleaning them after heat treating would likely take a lot of effort. I think I would be a little bit embarrassed to make a gold plated hammer.

Any thoughts?

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04/13/2025

Grandson DAMMERRing

04/12/2025

In the last post I reported the trouble I had with the epoxy for some plastic/fiberglass handles. I removed the heads from the three hammers that had bad epoxy and mounted them on some 14 1/2" wood handles. They look better and are better. I also tried something new with the wood handles. Before mounting the steel tube and head, I submerged the wood in boiled linseed oil inside a vacuum chamber. I applied vacuum for a few minutes during which the air coming out of the wood created a lot of foam and made a mess of my vacuum pump. When the vacuum was released, the wood sucked up a lot of linseed oil which will eventually polymerize and should help with moisture resistance.

03/22/2025

I made five hammers with the magnets and a regular pick. I mounted them on plastic handles with fiberglass cores. They are 16-14 inches (42 cm) long. It's a bummer because there are two problems.

For three of them, I tried a different epoxy that turned out to be somewhat brittle. I abused the hammer in the photos by whacking a big rock as hard as I could and using it to pry on my big bench vice. Some cracks appeared near the top, but the handle is still tight. The handle can't fall off since it is pinned to the head, but I'm pretty disappointed and will have to decide if I want to try to get the heads off and mount different handles or let them go as is.

While whacking away, I found that the plastic handles sting your hand a lot. I put a glove on, but it was still uncomfortable to hit hard. I compared it to a hammer with a wood handle and the wood handle was fine. This isn't a problem for the hammer's intended use on beaks, but drilling with it would be uncomfortable.

I've always disliked mounting fiberglass handles because the epoxy is such a pain and a mess, but also it's a struggle to get them on straight and square. I think I will give up on plastic handles.

Addendum: I drilled some 3/8" holes with this hammer and there was no problem with the comfort of the handle and the head seems stable.