Hairminator

Hair'll be back!

Ever since Ally went through chemo, her hair has been a bit thin. One of the deals I found was a Hair Restoring device from Costco for $380.00. It didn't seem like there was a lot to it, but many similar models sell for $1000 with 80 lasers instead of just 40. I did some web surfing to see if there was any more "info" about it, and there certainly is a lot of talk. There are lots of comments regarding how well it works and also how it does nothing. There are even a few "studies" on it's effectiveness, and what I deduced is that maybe it works or maybe it doesn't. But probably not likely enough to throw $400 at it to find out. It doesn't really look like there is that much to it and I found a YouTube video where a guy made it a DIY project: Laser Hat. His website HowToLou has lots of other fun projects worth checking out too.

I found out I could get 120 of the lasers for about $32 on ebay. Just the entertainment value is worth that much even if it does nothing. Here are a few links about this:

• Randomized Controlled Trial

• Healthline

• Kiierr

• Theradome (Costco was selling this)

Getting Started

The first decision is 5v or 3v lasers. 5v works easy with an external supply, but 3v would would work well with 18650 batteries.

• 5v lasers require 20ma per device, so 100 diodes would need a 2A 5v supply. They could be connected directly. I could use a USB battery to drive it. This seems like the easier option.

• 3v lasers require 40ma per device or 4A. the 18650 battery are 3.7v and probably around 3000mah (even though the batteries say 9800 mah). I probably shouldn't pull more than 3A, so I could do 100 lasers at 2x 2A which would last 1.5 hours. I would need to drop the voltage down to .7 volts, but I could have it processor-controlled and use a pwm and put in safety features.

The HowToLou version just pushed the lasers into some foam and glued it into a hat, then twisted the wires together. A fancier way would be to 3d print a helmet or make pcb holders and solder the lasers on. The overheating problem would be better with the pcb. But I think I will do an improved version of the foam using 1/4" think foam sheets and molding into the shape of a helmet.

The next decision is how many lasers and what voltage. 5v seems the easiest. Also, they are so cheap, so I got 120 of them.

Safety: I should add a momentary switch that clicks on when the hat is on your head.

12/30: I checked the order tracking and it looks like the lasers should be here soon, maybe today. Time to start thinking about it more. I ordered some glasses to filter the red light. It looks like I should be able to control the lasers with a few mosfets and a processor.

Helmet

There are lots of youtube videos on making a foam helmet. Here's what I did:

Adding lasers

The next step is to insert the lasers into the helmet. I cut about 110 holes in the helmet. Before inserting the lasers I ground off the end of the lasers to remove the lens. This makes a large laser spot and hopefully makes the lasers a little less dangerous if you accidentally look at it. Connect all blue wires to each other and then all the red wires. I decided to replace the existing wires with new wires to make it look neater and also allow me to eventually turn on rows individually.

Wiring and Testing

I bought 5 volt lasers, so I just had to connect ground to the blue wires and 5 volts to the red wires. The lasers need about 2 amps of current. I initially connected a 5v 2.6A power supply to the helmet. The 5 volts from the supply connects to a micro lever switch that connects to the red wires. I cut a hole in the helmet to hold the micro switch with the lever inside so that the helmet must be on your head before it will turn on.

Later I replaced the power supply with a LiPo battery and two DC-DC converter boards. The battery holds 800mah which is just enough for a 25 minute Hairminator session.