How does one build a custom laser pointer?

[paul1598419]

I found some axial lead 10 amp silicon rectifiers on eBay, 50 for ~$5.00. That was sometime ago, but they are likely still available. These are larger than what you would normally see in consumer electronics power supplies. These work fine for current up to 4 amps. If you use them for higher currents they tend to get hot as they are not actually performing as a rectifier, but have a CC through them.