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    • May 25, 2017 8:23 PM EDT
    • I so agree David!

      By comparison, their competitor (Johnson) not only took my order immediately, they notified me within an hour that they had cut and shipped it. And they apologized that it would have to ship all the way from Minnesota -- which is perfectly fine! 



    • May 25, 2017 6:25 PM EDT
    • Cliff Jennings said:

      [EDIT] The Gemini people said they only talk to distributors, and sent me to one. But the distributor said they only deal with retailers, and sent me to one. But the retailer's phone number was no longer in service. Where I grew up, they call that a hint. 

      So it was like they were saying; "Go away boy, you bother me". In today's market, where so many companies are chasing what few dollars are available out there, that attitude surprises me more and more. 


    • May 25, 2017 4:47 PM EDT
    • I updated the cutting pattern based on stock size and a better randomizing of shingle widths. I was going to put it here, but now I see the image updated automatically where I posted it a few emails ago. Atta boy Bob!!




    • May 25, 2017 2:49 PM EDT
    • Thanks Steve! And thanks to you & John for the alcohol tips, those are always welcome. ;) Seriously, I intend to jump on that with the shingles, which are coming next.


      I've been corresponding with Dennis (thanks Chris), and he had the great tip of using colored plastic for the shingles. He's had some out for 5 years, and still holding their color. So I'm looking into doing the same, though in a forresty-green color. Might take a couple weeks to get, but the more I think about it, the better that sounds. Painted white styrene is probably not the best for a roof.



      This company has something similar,


      Either way, I'd like to pre-grain the green plastic (it's acrylic, very weldable), pre-treat with ink and alcohol, and then laser. After that, we'll see.


      Thanks guys for all the help, and thanks Dennis for steering me in a better direction.



      [EDIT] The Gemini people said they only talk to distributors, and sent me to one. But the distributor said they only deal with retailers, and sent me to one. But the retailer's phone number was no longer in service. Where I grew up, they call that a hint. 


      So I decided to go with Johnson Plastics, who permits on-line orders, which I just did. I think their prices are good, and shipping fair. I called them before ordering with a couple of questions. They confirmed that this particular material is PVC-free and intended for laser-cutting; that it is acrylic and bondable; and that the color is all the way through (not just on the surface, and not like a two-layer thing with white as a second layer).  


      Hopefully I'll be cutting the shingles a week from now.  


    • May 24, 2017 7:27 PM EDT
    • John Caughey said:

      Try rubbing alcohol to get the ink to 'lay down'. It is a wetting agent and should pull the ink into the crevasses.

      Try to keep the details contained on each board, it will help fool the eye.

      Maybe you could engrave some detail deeper on each than the sanding to do the above...


      Looks great, but I really think you should try to get serious with your hobby!


      Your concerned net bro,


      Cliff, I came to this thread very late.  Dunno how I missed it.  Great work!


      I agree with John, regarding the use of isopropyl alcohol.   I use 10% solution of India Ink in isopropyl alcohol.   Slowly build it up to taste.  It won't look like much, at first, but you will have absolute control over the process.

    • May 24, 2017 4:49 PM EDT
    • Here's the pattern for the shingles.



      Each shingle strip is 3/4" wide, mirrored over, and copied. The shingles will have a nominal 3/8" exposure, though with slight variances in angle and height. There are minuscule gaps between shingles, but it may take some experimenting before they become distinct enough.The strip lengths are over-long, to randomly park them over the next lower row. If anyone wants this pattern (in dwg, dxf, pdf or jpg), feel free to PM me. 


      This is to be laser cut from the same .04 styrene as the exterior sheathing.  I plan on "pre-graining" the sheet similar to the sheathing, by using a coarse-grit belt on a sander, and maybe taking a wire brush (in a drill) to it like Dennis & I were discussing a while back. 




      [edit, 5/25: pattern updated]

    • May 24, 2017 7:40 AM EDT
    • Thanks guys, all good thoughts. 


      I heard back from SciGrip (same company as Weld-On), and they recommended #4052. It has 3 times the working time as the #16, is slightly more viscous, and is formulated for both styrene & acrylic (and other plastics). So I'll give that a test. 



    • May 23, 2017 11:05 PM EDT
    • Cliff the #4 numbering system doesn't really apply to your application ... Don't try and finesse the glue for outdoor use .

      Check out the contact adhesives (which opens up another can of worms)

    • May 23, 2017 9:11 PM EDT
    • Maybe not, but it sticks.  Crafters Goop and those types of adhesives will also peel.

    • May 23, 2017 7:16 PM EDT
    • Thanks Todd, I'll have to check that out. But if it peels away, it's not chemically welding. 

    • May 23, 2017 6:16 PM EDT
    • I use Loctite GO2Glue for acrylic.


      The working time is ~1/2 hour and you can wipe away excess without "marring" the acrylic.  It is a flexible bond much like a thin coat of Crafters Goop, and you can "peal" away excess.



    • May 23, 2017 5:52 PM EDT
    • About the glue. I've been using Sci Grip #4 (water-thin) and #16 (thick). Thin is for smaller detail parts, thick for where gap filling is important. The problem is with large areas of styrene to acrylic. Here's some comments I passed on to Sci Grip, hoping they give some recommendations. 


      I'm cementing large amounts of .04 stryene sheet to 3/16 acrylic sheet. I've been testing with #4 and #16.
      #4 is good around the edges, but it's tough to brush onto the main area to be adhered. 
      #16 is better for brushing on, and helps where I need filling.
      However, the #16 tends to set very quickly, almost like the styrene is soaking it up. I need a little longer working time, because the pieces can be as big as 2' square. 
      Also, the styrene tended to melt a little and buckle, producing undulations on the exposed surface.
      So, we'll see what they say. 
      [edit] The reason this is an issue is because it was difficult to brush the #16 onto the entire back surfaces of the styrene without it beginning to kick. This is spite of a 4-5 minute working time (for acrylic); I had only 1 minute max. So I had to re-brush over areas where it looked dried. It was almost like the styrene was soaking it up; and in fact, it is almost foamed in some areas (looking from the rear, through the clear acrylic). This resulted in a lot of buckling. So. I need a different formulation that will be kinder to the styrene, yet still weld it to the acrylic.
      Yeah, I could have done more research on the Sci-Grip site, but I'm lazy, and so I'm letting them make the call. Also, the cans can be expensive, so I'd like advice before committing to ordering.

    • May 23, 2017 4:43 PM EDT
    • Thanks for the tip Chris, will do.

    • May 23, 2017 4:41 PM EDT
    • You should chat with Dennis, he has some special stuff he lasers his shingle strips out of that he says works really good.



    • May 23, 2017 4:39 PM EDT
    • I sure hope to, Chris. I'm almost done with this trim business, and need to start making patterns for the shingle strips. 

    • May 23, 2017 4:33 PM EDT
    • Are you going to laser your shingles Cliffy?



    • May 23, 2017 4:26 PM EDT
    • Yeah Forrest, the white sure looked way out of place!  :)


      Glad you like the skylights Sean, haha! Stupid me though, I should have only masked the back of the window, and sprayed all the underside black. Otherwise I'll have nice glowing shingles when I put a light in! Same with the main building, too much bleed around the window & door frames. So I'll need to mask just the window insides and spray all the interior black. 




    • May 23, 2017 1:43 PM EDT
    • Sean McGillicuddy said:

      Love the skylights!

      Yep, that almond will turn out to be a good choice over stark white.

    • May 23, 2017 9:59 AM EDT
    • Love the skylights!

    • May 21, 2017 3:59 PM EDT
    • Thanks Jerry, thanks Travis!


      Today I had fun installing some detail bits. But first came the realization that the later door widening didn't get conveyed to the sheathing people. I tell ya, you just can't find good help anymore.



      But that was solved and the door and windows got glued in fairly rapidly. Next came the corners, where I had to scrape away some paint. I had best success for that with a swivel debur tool.



      Since the building is fairly weathered, I painted the "white" trim with 'almond' spray paint.  Here's how the thing looks at this point.



      The other side, showing the stack assembly.



      I was going to install the roof braces, but found that the carpenters totally hosed up the left side... sheesh... so some 3d printing is now taking place, the results of which will have a brief spritzing with some almond Krylon.


      Thanks for viewing!