I need Help I need to get a decent CNC machine don't have to much to spend

[theceo]

I am in the US

[JAZZCNC]

Here is a sign I cut the letters for on my Chinese 50W laser. The sharp corners would have taken an absolute age to get right on an industrial router never mind a 3040 with a shitty DC spindle.

So what cutting length do these 50W lasers have because that looks like long sign or is it optical illusion.? Most cheap lasers I've seen have only been 500 or 700mm max and that looks longer or is it Joined.?

[Doddy]

Just to throw a curve-ball here.

Komatias - how do you find cutting wood affects the optics? (I'm thinking resinous smoke deposits on the mirrors) - Not necessarily a game-changer, but I'm thinking that it needs to be considered here. I would agree if you can cut with a laser this must be a good, viable solution, but I have avoided particle/laminate boards up to now with my 40W chinese (not that acrylic is particularly clean).

I'm surprised that 50W will cut 1/4" - but will take your advice on this. Perhaps I need to grow a pair and get some ply in mine - I've plenty of 1/4" knocking about and a project that needs an enclosure (ironically, to contain a laser - but only 1W 450nm... though that nearly set fire to my shed). Maybe a couple of passes will get through.

[theceo]

Ok Komtias I looked at one of these machines looked small is that big enough to make a 11inch tall and 10inch wide letter plus what type of power does it use.

[komatias]

The total sign was 1.4m long. I split the letters and nested them on multiple 600x250mm sheets. The designer I did this for, then tacked and glued all the letters together.

Wood makes a lot of smoke but that is why you will need to buy a good extractor fan.

Most lasers nowdays come with air assist. This is basically a nozzle that allows air to come out where the focused laser beam exits. It also ensures that you dont start a fire while cutting. You really only clean the final concentrating lens once a month.

[komatias]

Just to throw a curve-ball here.

Komatias - how do you find cutting wood affects the optics? (I'm thinking resinous smoke deposits on the mirrors) - Not necessarily a game-changer, but I'm thinking that it needs to be considered here. I would agree if you can cut with a laser this must be a good, viable solution, but I have avoided particle/laminate boards up to now with my 40W chinese (not that acrylic is particularly clean).

I'm surprised that 50W will cut 1/4" - but will take your advice on this. Perhaps I need to grow a pair and get some ply in mine - I've plenty of 1/4" knocking about and a project that needs an enclosure (ironically, to contain a laser - but only 1W 450nm... though that nearly set fire to my shed). Maybe a couple of passes will get through.

Doddy,

40W will cut through 3mm ply in one pass but 6mm in two or three depending. You need to have a look at getting an air nozzle on you machine if it is the chinese 40W one.

[komatias]

Ok Komtias I looked at one of these machines looked small is that big enough to make a 11inch tall and 10inch wide letter plus what type of power does it use.

Although not 80W this one is one that I would definitely consider buying it has 700x500 cutting area (27"x19"). Again at the price you will need to ensure you are up to the task of maintaining it.

http://www.ebay.com/itm/1-Value-USB-...AAAOSwHnFV2tp4

I see that the 80W are roughly twice as expensive and considering you can get most of the work done with 60W, I do not think you need any more than that.

[Doddy]

Doddy,

40W will cut through 3mm ply in one pass but 6mm in two or three depending. You need to have a look at getting an air nozzle on you machine if it is the chinese 40W one.

Yup, mine came with an air-assist nozzle - and a handful of coiled rigid air pipe. That quickly got replaced with an energy-chain to contain a flexible (ok, aquarium) 4mm silicone air tube, as well as a 2-core ribbon to supply the two laser line-generators that a 3d-printer bracket held to provide x-hairs (don't think to use a x-hair lens/laser assy, as you can't guarantee the focus/alignment, you really do need two single line generators, one on each axis).

My real problem with chinese lasers is the absolutely crap software. I need to adapt the machine to be driven from g-code, but I've struggled to justify the cost.

[theceo]

i hear you on the laser but it just seems like to me that a drill bit would cut wood cleaner and better than a laser maybe not metal but definitely wood,

[dodgygeeza]

absolutely not, a laser will cut it faster and a lot cleaner than a router.