Page 2 of 2 FirstFirst 12
Results 11 to 19 of 19

Thread: UK based laser builder/GURU advice

  1. #11
    Join Date
    Feb 2009
    Location
    East Coast of Southern Virginia
    Posts
    536

    Default

    Once you decide which unit to get. Contact the manufacturer and get technical drawings for the module, diode driver, and power supply. These drawings will show you how big each part is. It will also show you the location of the laser beam output so you can see if they line up with your scanners or if you need to redirect it. The RGB modules usually come with a suitable AC to DC power supply. You can then determine if and how it will fit in with your projector. If the supplied power supply does not seem to fit you can look for a different one that is smaller or a different shape (we can try to assist with this).

  2. #12
    Join Date
    Nov 2019
    Location
    Bedford, U.K.
    Posts
    18

    Default

    Thank you, I’ll get something ordered up

  3. #13
    Join Date
    Jan 2006
    Location
    Charleston, SC
    Posts
    2,147,489,446

    Default

    If you purchase one of the RGB modules from GoldenstarLaser.com, it will come with a dedicated AC to DC power supply.

    You'll need to remove the 3 existing lasers from the case, along with their associated drivers and the power supply that feeds them. (Pretty sure that's the large black plastic PSU in the picture you posted.) You'll also need to remove the two dichro mounts. Then you need to mount the new laser head in the case. I'd suggest you mount the module with the beam pointed towards the front of the case, and then install a bounce mirror on a kinematic mount to reflect the beam 90 degrees to the left so it can enter the scanner block. This will allow you to use the adjustments on the kinematic mount to "steer" the beam so it lands squarely on the middle of the first scanner mirror.

    In a perfect world, you would want to ensure that the beam height exiting the new module (measured vertically from the baseplate) is the same as the height of the middle of the first mirror in the scanner block. True, the kinematic mount will allow you to correct for quite a bit of height miss-alignment, but this means that the beam will enter the scanners on an angle (either up or down, compared to the baseplate), and this will create a slight geometric distortion in the scanned image. A few mm one way or the other is fine, but if you are way off, you might want to consider installing shims under either the laser module or the scanner block to bring everything closer to the same horizontal plane.

    Then you'll need to install the driver and power supply for the laser module. Just need to find space somewhere in the case; I think you'll have plenty of room. The new laser module will have inputs on the driver for the red, green, and blue color modulation signals. When you remove the old lasers, you'll disconnect those modulation signal wires from each driver. Then just re-connect them to the appropriate inputs on the driver for the new all-in-one RGB laser module.

    You'll also have to supply AC power to the input of the new power supply for the RGB module. The DC output of the new laser power supply connects to the driver module for the all-in-one unit. All of the necessary connections are marked, so connecting the wiring is fairly simple. It's likely that you won't even need to solder anything, as the inputs should all use screw-terminal connections.

    To purchase the kinematic mount, you can grab one off Ebay (this would be my choice), or you can buy one at retail from Edmunds, Thor Labs, or similar. Something like an MM1 is what you want. (Basically it's a mount designed to fit a 1 inch square optic.)

    Technically, you only need a 2-axis mount, but they do make 3-axis mounts as well. (The third adjustment moves the entire mirror forward or backward slightly.) These 3-axis mounts are more important when you're combining multiple beams using dichros, but having that third adjustment would also be useful for your build. If you can get one without paying double, I'd go for it. (Just be sure you have room in the case for a 3-axis mount, as that third adjustment screw often sticks out quite far compared to a standard MM1's dimensions.)

    You'll also need a small bounce mirror; this needs to be a FIRST SURFACE mirror. You want one with at least 96% reflectance (or better). It doesn't need to be very big; 15 mm is probably enough, although 1 inch mirrors (20 and 25 mm) are more common. Either round or square form factor is fine. I suggest you avoid any mirrors that are larger than about 35-40 mm though, since a big mirror will just take up extra space, plus it will be more difficult to mount.

    Regarding the mounting of all the components to the baseplate: Once you figure out where everything will be positioned, you'll need to drill new holes in the baseplate. Then you have two options: 1) you can drill the holes slightly smaller than necessary and then use a tap to cut threads in the holes so everything screws directly to the baseplate, or, 2) you can drill the holes slightly larger than necessary and then through-bolt everything using nylon insert lock-nuts on the underside of the baseplate.

    Option # 1 makes for a very clean looking build, but you need to be careful when tapping the holes. (Taps are very brittle and can easily snap if you are careless.) Option # 2 is quicker and doesn't require you to purchase a set of taps, but having the nuts on the underside of the baseplate means you have to pull the entire baseplate out anytime you want to make changes. (Can't access the nuts on the underside without pulling the baseplate.)

    Adam

  4. #14
    Join Date
    Nov 2019
    Location
    Bedford, U.K.
    Posts
    18

    Default

    Right, well given the response you’ve spent so much time writing, it sounds like I’d better give it a go then!

    I have FB3 waiting for pick up Saturday, so that’s one box ticked, and all ready have a tap and die set so that’s another.

    I’ll get a laser unit ordered up along with a bounce mirror and kinematic mount shortly then see how it all looks like it’s going to fit and start working through it

    Thanks very much to you all for all the input and help so far, watch this space!

  5. #15
    Join Date
    Nov 2019
    Location
    Bedford, U.K.
    Posts
    18

    Default

    Quick interim laser chums - picked up FB3 yesterday and had a quick play last night. All I can say is WOW, i should have invested in it ages ago, it’s going to be a huge improvement already over what I was using previously

    Now to improve the laser itself!

    Enjoy your weekends everyone

  6. #16
    Join Date
    Nov 2019
    Location
    Bedford, U.K.
    Posts
    18

    Default

    Hi all

    im just about to pull the trigger on a new RGB module. The Goldenstar 3w one as linked earlier in the thread is going to cost near on the same as this Techhood 5w one.

    Goldenstar 3w

    http://goldenstarlaser.com/index.php...product_id=398


    Techhood 5w

    https://www.ebay.co.uk/itm/RGB-5000m...-127632-2357-0

    Could anyone give any opinions between the two please in terms of quality/longevity etc before I press the button and order?

    Cheers
    Si

  7. #17
    Join Date
    Jan 2006
    Location
    Charleston, SC
    Posts
    2,147,489,446

    Default

    Quote Originally Posted by stepawayfromthemachine View Post
    im just about to pull the trigger on a new RGB module. The Goldenstar 3w one as linked earlier in the thread is going to cost near on the same as this Techhood 5w one.
    Goldenstar 3w http://goldenstarlaser.com/index.php...product_id=398

    Techhood 5w https://www.ebay.co.uk/itm/RGB-5000m...-127632-2357-0

    Could anyone give any opinions between the two please in terms of quality/longevity etc before I press the button and order?
    The divergence on the Goldenstar module is <1 mrad, but the Ebay listing for the Techhood module lists the divergence as <3 mrad, which is pretty terrible, to be honest.

    Another warning sign is the fact that the Techhood unit says "TTL Modulation, Analog Modulation Optional." This sounds like they are being intentionally vague; does the module listed in the auction support analog modulation or not? (Because pairing it with a cheap driver that only supported TTL modulation would be one way for them to save on cost, just as skimping on collimating optics for the laser diodes would also save on cost - at the expense of a lousy beam profile.)

    Bottom line: I would stick with the proven Goldenstar module. Several people here have ordered them and used them, and they are pleased with their performance. It's a known quantity.

    I haven't heard anything about the Techhood unit, but just based on the specs in the listing (and the absurdly low price), I already have serious doubts regarding the quality of the unit.

    That's my opinion anyway; if you think you need 5 watts, just get the 5 watt module from Goldenstar. (Or split the difference and go with the 4 watt module, as it is only $80 more than the 3 watt unit.)

    Adam

  8. #18
    Join Date
    Nov 2019
    Location
    Bedford, U.K.
    Posts
    18

    Default

    That’s good enough for me thanks Adam 👍🏻👍🏻👍🏻

  9. #19
    Join Date
    Nov 2019
    Location
    Bedford, U.K.
    Posts
    18

    Default

    Hi all - just wanted to book end this thread.

    My order from Goldenstar turned up with no fuss from China as promised. I’ll be completely honest and say I just wasn’t happy carrying out the work myself, so got in touch with Rob at RK Photonics who was local to me in MK who has done a great job on installing the new unit.

    I did a trial run last night without any haze and I’m absolutely chuffed with the results, so thanks to all here for your guidance and help, and thanks to Rob for his skills

    Here’s what it looks like inside now, little bit empty, but a lot more powerful!
    Attached Thumbnails Attached Thumbnails E576589E-ACFE-467C-831C-204D9AF2BAAD.jpeg  


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •