Welcome to Our Community

Some features disabled for guests. Register Today.

+Laser

Discussion in 'Laser Cutters' started by BNMaker, May 3, 2018.

  1. BNMaker

    BNMaker Well-Known
    Builder

    Joined:
    Jul 13, 2017
    Messages:
    23
    Likes Received:
    6
    BNMaker published a new build:

    Read more about this build...
     
  2. BNMaker

    BNMaker Well-Known
    Builder

    Joined:
    Jul 13, 2017
    Messages:
    23
    Likes Received:
    6
    As I was looking round my play room I realised I had about 35M of various sizes of v-slot extrusion, another 20m of 2020 extrusion, a bunch of NEMA 17s and 23s, dozens and dozens of micro controllers, stepper drivers, odds and sods of fixings, screws, plates, switches, etc. and needed to make something.\

    I have been laser cutting for a while now, courtesy of my mate's laser bureau, but often I would hold off on a job because it was too small to send for commercial cutting.

    I make things from paper, card, foam board, corflute, balsa, thin ply, thin MDF, etc. and can be found of an evening with an Xacto knife in my hand. So,. what better than a small laser diode to cut stuff with?

    I looked at the ACRO and thought it was just the job - even if it was going to end up being bigger than my Ox.

    I make model planes, and using big sheets of A2 and A1 foamboard means you can make bigger, stronger wings and fuselage, without compromising structure. I also make pop-up cards, pop-up architecture, 3d 'shadow box' articles and foam-board architecture for modellers, so being able to cut a whole A2 sheet in one go was going to be a big bonus.

    As I was trolling the googles, I saw a cheap pressed-steel 3D printer for under $200 that used a 'cross' style of gantry that only used one motor for the X-axis.

    So, I set to to work out how I could make such a beast in an affordable way to carry a laser diode.

    After a few mock-ups of mdf and gaffer tape to get the weight sorted out, I was sure I could reliably and rigidly mount a laser diode on a cantilevered axis without bounce or jitter.

    So, that's what I've done.

    [​IMG]
     
  3. BNMaker

    BNMaker Well-Known
    Builder

    Joined:
    Jul 13, 2017
    Messages:
    23
    Likes Received:
    6
    What I didn’t have any of, and what I’ve been substituting ‘regular’ extrusion for is v-slot 2020.

    I ordered 5 600mm lengths and it arrived today, along with a bunch of mini-v gantry sets.

    So, tomorrow is ‘build a mock-up’ day, where I’m going to put together a working prototype using a cheap grbl shield ($5!!) and some spare Pololu drivers, a Due copy running G2Core (further development of TinyG) and all the final mechanicals, but without the diode, which is stuck in the post somewhere between Singapore and Borneo.
     
  4. BNMaker

    BNMaker Well-Known
    Builder

    Joined:
    Jul 13, 2017
    Messages:
    23
    Likes Received:
    6
    DE173B18-EDFC-40CB-8F52-3F9071C194F9.jpeg A40A268D-39AE-46DA-B769-96244C952EA2.jpeg Today did the first test build, just to decide on which extrusion to use, what final size to make it, checking up on the balance for the cantilever, etc.

    I tried 4020 and 8020, but 6020 is fine - gives enough of a spread to counteract most of the lever action from the cantilever. I will double up some sections of the y-axis acrylic plates to ensure it can take the weight. I was surprised how stable it was, just with a single stabiliser bar, but then the weight of 1500mm of 6020 v-rail is way more that the whole rest of the assembly. If I had access to a laser or waterjet that could cut 3mm alloy plate, I would make them from that, but TIB (this is Borneo) and there’s bugger-all in the way of precision engineering here. I can’t use the 150W CO2 laser as it’s strictly used for signage - acrylic, vinyl, poly, timber and I don’t think they would like me leaving aluminium residue all over the place. :(

    I’m conscious that the mass of the Y-axis includes both of the motors and the entire X-axis, so will have a look at what other steppers I have. I will be ‘double belting’ the 3mm GT2 and it is genuine Gates belt, not a Chinese knock-off. I bought a whole roll a few years ago. Comparing it to the bit of belt I got with my last 3D printer, it’s way more flexible, wider, better ‘teeth’ and the base layer is heavier. The Chinese belt feels very plasticky and slippery. I’ve used double-belting before and found it is far better and pretty much eliminated the bounce and chatter you can get from a heavy gantry starting and stopping.

    So tomorrow I will finalise the drawings and get the rest of the bits together (can’t find my spacers or eccentric nuts - may have to order more, which is a pita - 3-4 week ‘express’ shipping to here from anywhere, or $50 for seven day shipping, so no. And Ramadan started today, so everything is slower and less efficient than normal for the next lunar month...).

    Even with the weight of the Y-axis extrusion, it’s going to be a light machine and should be easy to stand against a wall when not in use.

    I’m trying to work out a minimalist way of setting up limit switches. In theory I should be able to get away with two, but right now trying to work out how to trigger a single switch at both ends of the limit of travel is going to hav3 to take second place to dinner prep.
     
    Mark Carew likes this.
  5. Mark Carew

    Mark Carew OpenBuilds Team
    Staff Member Moderator Resident Builder Project Maker Builder

    Joined:
    Jun 28, 2013
    Messages:
    2,036
    Likes Received:
    1,289
    following! - Doing great @BNMaker keep up the good work :thumbsup:
     
    BNMaker likes this.
  6. BNMaker

    BNMaker Well-Known
    Builder

    Joined:
    Jul 13, 2017
    Messages:
    23
    Likes Received:
    6

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice