Forum Sponsorsss


Forums General Track and Trestles
  • Topic: New Trestle Going In..., Totally Unique!

    Back To Topics
    (0 rates)
    • March 14, 2019 7:54 PM EDT
      • Santa Ana, CA
         
      • Posts
        1,598
      • Thanks
        1
      • Thanked
        126

      New Trestle Going In..., Totally Unique!

      My trestle is now over 15 years young (this is the second), and this year it gets replaced.

       

      I've gotten older/lazier and rather than buy, load, cut, glue, and nail wood for over a dozen and a half bents, probably cutting myself several time in the process, it is now far easier to let the computer do the work.

       

      I've been wanting to just cut the bents out of 3/8" acrylic sheet on the laser cutter, but 3/8" acrylic is costly (i.e., $70 a sheet for a 2' x 3' piece in minimum lots of 5 sheets). The only way that I could do this, and justify it economically, would be to let the laser cut the sheets into individual sticks, and deal with these as I would sticks of wood.  The advantage is that the laser would cut all the bents to the proper lengths with the right angles at the tops and bottoms and the holes for easy assembly.  A step in the right direction, but still a lot of work.

       

      Then last week I saw that Airwolf 3D, maker of 3D printers, was selling off sheets of 3/8" smoked acrylic sheets in 3' x 2'..., at just $20/sheet!  They were using this to make one of their discontinued models.  They even agreed to throw in an extra sheet if I bought 10!  So, at $770's worth of acrylic for just $200 (~$18.25/sheet), I can afford to let the laser do the work and chuck the excess material rather than deal with so many individual sticks.  I can get 3 and maybe 4 bents per sheet, so, as little as $5 a bent!

       

      And, rather than glueing these things together, I've devised a method that attaches the crossbraces using 2MM x 35MM stainless screws and nuts and the shape will secure the horizontal runners.  Will probably be the only smoked acrylic trestle in existance!  BTW, it will take about an hour and a half per bent just in laser time.

       

      This shows my test pattern as well as a set of the four crossbraces.

       

       

      This post was edited by Todd Brody at March 15, 2019 3:56 AM EDT
    • March 14, 2019 8:27 PM EDT
      • Defending the State of Exile! ,
         
      • Posts
        13,342
      • Thanks
        1,527
      • Thanked
        1,011

      Todd Brody said:

       

      Then last week I saw that Airwolf 3D, maker of 3D printers, was selling off sheets of 3/8" smoked acrylic sheets in 3' x 2'..., at just $20/sheet! 

       

       

       

       

      String Fellow Hawk is dead man !

    • March 14, 2019 9:18 PM EDT
      • Shut Up Rooster
         
      • Posts
        8,339
      • Thanks
        151
      • Thanked
        653

      there's a guy who laser or water cuts ABS for bridges and then ships all the stuff flat. Seems to work for him.

       

      So, if you get a great price on acrylic, there you go.

       

      Greg

      ____________________________________

      Be sure­ to visit ­my site, l­ots of tec­hnical tip­s and modi­fications,­ and you c­an search ­for topics­ and key w­ords.


      ­Click HERE for Greg­'s web sit­e
      PLEASE NOT­E: Please do NOT use private messaging, i­f you have­ a questio­n, feel fr­ee to emai­l me priva­tely, u­se regular­ email onl­y: greg@el­massian.co­m

    • March 14, 2019 10:15 PM EDT
      • West Glocester, Rhode Island
         
      • Posts
        370
      • Thanks
        52
      • Thanked
        88

      Todd, Will you also use the laser to engrave a wood grain pattern?

      ____________________________________

      Thingiverse Icon Instagram Icon

    • March 14, 2019 10:49 PM EDT
      • Santa Ana, CA
         
      • Posts
        1,598
      • Thanks
        1
      • Thanked
        126

      Dan Gilchrist said:

      Todd, Will you also use the laser to engrave a wood grain pattern?

      No.  It would only be on one side of the pattern without much added work to cut the second side, and it would much lengthen the time on the laser.  You couldn't even do the other two sides at all.

       

      The outter edges (that you can't do at all) are cut in "steps" and will appear as a ripple pattern.  I can only book 1-1/2 hrs on the laser at a time, and that's about what it takes to cut a bent and the 8 braces.

       

      I did do the wood pattern when I did the gallows/dunk tank for the build challange a few years back.

    • March 14, 2019 11:06 PM EDT
      • West Glocester, Rhode Island
         
      • Posts
        370
      • Thanks
        52
      • Thanked
        88

      Todd Brody said:
      Dan Gilchrist said:

      Todd, Will you also use the laser to engrave a wood grain pattern?

      No.  It would only be on one side of the pattern without much added work to cut the second side, and it would much lengthen the time on the laser.  You couldn't even do the other two sides at all.

      Gotcha.  My experiences with acrylic are that it's prone to chipping so I wondered how you would add wood grain safely.  Will you drag a razor saw?

      ____________________________________

      Thingiverse Icon Instagram Icon

    • March 15, 2019 1:46 AM EDT
      • Santa Ana, CA
         
      • Posts
        1,598
      • Thanks
        1
      • Thanked
        126

      Actually, I'll probably leave them in the clear smoked and just spray them with clear UV paint to prolong their life a bit.  This adds to the uniqueness.

       

      Alternatively, I put acrylic parts in the sand blast cabinet and media blast it.  This frosts it and gives it tooth for painting.  I may do this and spray paint them in a brown or use shades of brown acrylic paint to get a wood simulation as in the pic where you see Babs sitting on the door to the dunk tank.  (When space is tight, our structures multi-task.)  I did this to the doors for the new temple that replaces the delapidated wooden church this season.  This also shows the "wood" effect I lasered into the decking as well as planking lasered in.

       

       

       

       

      This is a step for the new temple going in.  This is two pieces of clear acrylic glued together then blasted and ready to receive paint.

       

      This post was edited by Todd Brody at March 15, 2019 2:02 AM EDT
    • March 21, 2019 8:29 PM EDT
      • Santa Ana, CA
         
      • Posts
        1,598
      • Thanks
        1
      • Thanked
        126

      I cut the first acrylic bent and two more sets of the cross pieces today.  Each bent takes about 32 minutes to cut.   This is much quicker than I anticipated.  A set of four crossbraces takes about 9 minutes and there are two sets per bent.  These will be held together with M2x35mm SS screws and nuts.  This is smoked in color.

      This post was edited by Todd Brody at March 22, 2019 6:37 AM EDT
Forums General Track and Trestles

    Icon Legend

  • Topic has replies
    Hot topic
    Topic unread
    Topic doesn't have any replies
    Closed topic
    BBCode  is enabled
    HTML  is enabled

Add Reputation

Do you want to add reputation for this user by this post?

or cancel

Ads by Google