First time homemade laser - a few questions

Hi everyone,

I want to start by saying that this is my first post, I only discovered this website this past week and it is amazing. First, a little background: I'm a student at Clemson University and am currently a senior in Mechanical Engineering. One of my classes requires a working prototype of a manufacturing process. My group decided to model laser engraving, upon further research we realized we were in over our heads with our 200$ budget.

On to the point. We used this website to do research and it has been extremely helpful but we were unable to find any direct information to our current problem. We recently ordered a 1 Watt TO18 445 nm laser diode and a TO18 glass lens focusable housing case with a built in heatsink. Our problem is that we do not know how to focus the laser correctly so that it will etch and/or cut material. While the housing case has the word focusable in it's name, we doubt that it will focus to the extent we are hoping to achieve. Looking at this website it seems that most people here expand the beam with one lens and then focus it with another lens immediately after that. This seems like a great idea but we were unable to find detailed instructions on how to do this.

I realize that my knowledge of lasers is lacking (just starting looking into them and doing research about a month ago) so any tips, pointers, or general advice would be greatly appreciated. If someone else has already asked for advice on a project like this then I apologize for reposting but was unable to find it. Feel free to ask for more specifics about our project and I will provide everything I can.

kmlee said:

Hi everyone,

I want to start by saying that this is my first post, I only discovered this website this past week and it is amazing. First, a little background: I'm a student at Clemson University and am currently a senior in Mechanical Engineering. One of my classes requires a working prototype of a manufacturing process. My group decided to model laser engraving, upon further research we realized we were in over our heads with our 200$ budget.

On to the point. We used this website to do research and it has been extremely helpful but we were unable to find any direct information to our current problem. We recently ordered a 1 Watt TO18 445 nm laser diode and a TO18 glass lens focusable housing case with a built in heatsink. Our problem is that we do not know how to focus the laser correctly so that it will etch and/or cut material. While the housing case has the word focusable in it's name, we doubt that it will focus to the extent we are hoping to achieve. Looking at this website it seems that most people here expand the beam with one lens and then focus it with another lens immediately after that. This seems like a great idea but we were unable to find detailed instructions on how to do this.

I realize that my knowledge of lasers is lacking (just starting looking into them and doing research about a month ago) so any tips, pointers, or general advice would be greatly appreciated. If someone else has already asked for advice on a project like this then I apologize for reposting but was unable to find it. Feel free to ask for more specifics about our project and I will provide everything I can.

Click to expand...

Welcome to the forum! Thats pretty cool that ya'll used this forum to do research there are many extremely intelligent people here who hopefully can see your quick need and therefore provide you with everything you will need to get a handle on the project.

All I know about optics is this: keep focusing the beam until it reaches its smallest point, and at that point, there should be some interesting things happening, smoke, etching, melting, fire, who knows really lol (I guess it depends what your aiming it at). Just make sure everyone involved in the project has the proper safety glasses (I use these: [NoIR) with the ARG lens because dealing with a 445nm anywhere near +1W can cause serious eye damage, trust me!

Anyhow, don't forget to check into the "Welcome" section of the forum and tell us a little more about who you guys are.

Read all the stickies in the beginning of each thread and you'll be like most of us - here waaaaaayyy to much (It's a really good thing though) This is like an addiction for some... I know I'm sucked in and trying to learn as much as time alows.

I hope that the super ultra high powered vets of this forum come to your rescue and get your class off in the right direction. And when you finally get what you need, check back in here and give us an update, always cool to hear about progress...

Anyhow, this went to long so best of luck to you and your team and :beer:

Josh

Thanks for the quick response, we are actually looking at safety glasses right now in the library and didn't know where the best deal would be so that link is very helpful. However, due to our budget constraints 60 dollars for a pair of glasses is more than we can afford. We're working on speaking with our teachers to see if they will increase our budget to allow for higher quality safety gear. As of now we have spent 54.97$ of our current budget on the diode and casing with heat sink. Although we do realize that the laser and casing might not be exactly what we are looking for and agreed before hand to split the cost out of pocket if they don't end up working out.

I forgot to mention this in my first post but this is a semester project so the final prototype does not need to be made until late in April (the exact date is still undecided due to multiple unexpected snow days cancelling class). I also forgot to mention that safety is a huge concern for us as this prototype is going to be used to teach underclassmen about the manufacturing process itself. We're trying to make the creation of our prototype as professional as possible and we have already created a QFD chart (quality function deployment) to brainstorm different ideas of how the laser engraver will specifically work, and our current idea is to fully enclose the process and have it visible via an installed camera with a live feed to a computer. This will hopefully eliminate the chance of the laser reflecting and causing damage to anyone viewing the process. But I'm getting a little off topic. Our biggest concern towards safety is what materials are suitable/not suitable for engraving/cutting. For example, I know that materials with chlorine (like PVC) should not be cut because it releases toxic gas that is bad for both the machine and anyone in the room.

I will definitely keep you guys updated as we move forward with pictures (once parts begin to come in) and everything that we're doing.

kmlee said:

Thanks for the quick response, we are actually looking at safety glasses right now in the library and didn't know where the best deal would be so that link is very helpful.

Click to expand...

Keep in mind that the best deal may not necessarily be the best protection, and when it comes to protecting our eyes, well, you really only get one chance so do it right and get good protection the 1st time around - besides that, only the people directly involved with the build should be using them...