New Laser Project

[dgchessman2]

I've been using a friends Chinese laser for a bit over a year now in Tacoma, WA. I'm sure his is somewhere between 40-60w. Primarily it's been used for etching glasses and making small coins for the Ren Fairs and Pirate Fairs.

Having seen the limitations of the machine, talked to other local craftsmen, and seen the price of getting a whole new batch of coins made for my bar... I've decided instead to simply make my own machine via fundraiser on IndieGoGo. I've also already quietly gathered some other funding sources to make sure that I'm not leaning too heavily on crowdsourcing. One way or another, the fundraiser goes live in about a week, and come Jan 1 it'll be time to get parts in the mail and start assembling.... a big freakin' laser.

Having worked, programmed, and repaired sheet metal manufacturing turrets before, I'm confident this is a project I can tackle.

Having never specifically worked with lasers before, I'm ready and happy to admit that I still need to do a lot of research and learning to do.

I am looking for feedback on a few things:

a) Is there are true, generic list for parts required? I've seen many designs offered. I've looked through them, but I'm looking more for a section-by-section breakdown, regardless of design.

b) What are the cost comparisons between one type of movement and another? I saw the X,Y Movements posted on the Lightobject.com website, and liked what I saw in the larger movements... though I was sad to see the largest movements sold out. How do those prices on the packaged kits compare to ordering the parts and assembling it myself? Time I've got.

c) Can I use more than one laser on the same movement? It seems like a smaller more economical laser would do me for almost everything I need. But some tasks just need a Big Freakin' Laser (TM), and I'd like to have one around without any mechanical adjustments required. I've seen the beam-combining for laser pointers, etc. What about 2 different lasers? I'd only need to run one at a time.

d) I've seen people describe moving the final lens on the laser to focus and adjust for the thickness of materials... and I've seen people move the entire lower table surfaces to compensate. I had no plans for materials over 1" thick except for glass etching. But I assumed I could attach the rollers for rotating the glasses on a lower plane than the normal 'bottom' and still maintain the 1"-ish distance. Am I missing something?

e) I've seen people say these lasers can cut metal, specifically stainless steel and aluminium. Honestly, that is more than I can hope for.... but I certainly can't discount the idea! Does anyone have a clear, concise table of what laser wattages (roughly?) hand handle what types of metal? And I assume all of those numbers are with a O2 assist rather than just an air blast?

f) Is this the place to ask more questions as they come up? I'm sure they will....

Thank you ahead of time,
Kaz

[dgchessman2]

....not a peep? O_o

Wow.

[Ihrke052]

Hi Kaz,

I am very much new to the laser world but I am in the process of building my own laser and would be happy to try to answer some of these questions the best I can (and based on my build)

A) there isn't necessarily a list of parts I can give to you but there are definitely must have items. You will need the laser tube, a series of mirrors and focus lens, a water pump (and hosing), a PSU, a table/frame with a belt or rack/pinion to run the mirrors, motors for the table and the controlling components for the table (stepper drivers/dsp controller). You will also need some odds and ends to connect everything and get it installed (wire/nuts/bolts/etc..)

Everything on This list can be found in some form on this site and at a very affordable rate. With my build however I converted a plasma table (rack and pinion) to laser by building mounts around the stepper motors to hold the mirrors. I also have an older laser which requires external gas to be pumped through the tube and the gas gets spendy. I'm pretty sure the "sealed tubes" sold here do not require anything except water ( for cooling) and electricity though,which will save quite a bit of money in the long haul.

Other than that list of necessities you should have some safety items, exhaust fans, possibly an air assist (simple aquarium pump), a laser pointer and mount for aiming, and so on. I started with the basics, got everything going and am working now on fine tuning my build. The biggest advice I would give to you though is to know the size you will mostly work with, and build toward that. I bought a 4'x4' table which is a great option to have but a pain to align completely and I find myself doing much smaller jobs..

B) the stepper motors I bought were the mid range ones from lightobject and they do very well on my table (again a 4x4 so fairly large). Looking back I maybe should have sprung for a little larger ones just to be safe (if i ever decide to convert to a cnc plasma or router) but these have been fine so far. Laser machines don't typically carry much weight (the mirrors/mounts are fairly light) so mid range is a good bet.

C) I don't know that any mirror exists that would let through say a 40w beam but reflect an 80w but if you really want to go this route I'm sure you could build your table to have 2 lasers but you would have to manually remove a mirror when you change them out. Again aligning mirrors can be a headache so I would try to avoid that if possible.

I would personally just get a larger tube. If they are taken care of they should last a very long time and if it's getting used a lot and reaches the end of its life, clearly things are going well for you also the any dsp controllers have power settings and you would just adjust that down for smaller jobs that require less power.

D) my focus lens is adjustable and the entire piece can be moved about 3" up or down which is nice for diff thicknesses but unfortunately I have no experience with a moving floor or rotary device so I cannot comment on those, sorry.

E) I havnt tried cutting metal but I wouldn't get your hopes too high. I've seen mixed threads about metal but I wouldn't hope for much more than etching into it. Metal should in theory just heat up from a laser and not actually cut but again I havnt gotten that far. I would be very pleased if I find it does though

F) this site has been a great resource for me and helped quite a bit. Sometimes answers may take a little while but Marco (runs the site) does a lot of traveling and also likes to test things personally on his end before answering, to give very accurate results. I had a very tough time when I started my build and became fairly overwhelmed but that's part of the building process. In the end I learned a lot more than I would have by simply buying a unit but it took much longer than I had hoped (and still not done!)

This info is all from my experience in the last couple months so I appologize if I didn't answer anything completely or if any of this info is a little off but I'll do my best to answer any others you have!

Heath