Question: "Scoring" ABS sheet/ adding a V-groove?

Discussion in 'General Modeling' started by OdiWan72, Aug 26, 2015.

  1. OdiWan72

    OdiWan72 Master Member RPF PREMIUM MEMBER

    Trophy Points:
    3,376
    Hey all

    I hope, that you model experts could give me some advice...

    I am currently building a Hoth scanner from scratch. To create the box, I cut the basic shapes out of 2,5mm ABS sheet and score the "folding-lines" with an Xacto blade, adding kind of a "V"-shaped groove to the backside. Once I removed enough material (without cutting THROUGH), I fold the box.

    Problem:
    by doing this manually, I don´t get consitent results. Sometimes I score too deep and cut through the ABS sheet, sometimes I score not deep enough (resulting in the folds not being crisp), sometimes the folds crack. :eek:hwell

    Is there a chance to cut the basic shapes of the box and its internal structures/ armor plating PLUS adding some kind of V-grooves to where I want to fold the box???
    Lasercutting does not seem to be an option, maybe a CNC router!?

    Many thanks in advance, Markus
     
  2. Laspector

    Laspector Sr Member

    Trophy Points:
    2,415
    Perhaps you could get a matte cutter? The kind where the blade slides? Might give you more consistency.
     
  3. OdiWan72

    OdiWan72 Master Member RPF PREMIUM MEMBER

    Trophy Points:
    3,376

    Already thought about this, but would it allow me to score the ABS (adding a V-phase) instead of just cleanly cutting? Can I adjust the depth of the blade?
    Having the ABS sheet milled seems to be my only option....pricey!!! :(

    Markus
     
  4. rbeach84

    rbeach84 Sr Member

    Trophy Points:
    1,406
    How big are the pieces you are working? I'd almost be inclined to make an 'angle sanding jig' and use that to smooth the 'rough' cut edges, then glue the assembly. If scoring, then you can make a depth gauge from styrene sheet (actually, block that is clear would be best so you can see what you're doing.) Basically, you need a block of the necessary thickness with a vertical slot cut in it for the scriber blade to pass through, up to the 'hilt'. Make it so the blade is restrained to the correct angles & depth. Start your score line without the block, then follow up with the gauge installed.

    That should give consistent depths. I also recommend using an actually engraving tool that is shaped to remove a kerf of material instead of 'plowing a furrow' in the ABS like a knife blade will tend to do. Your gauge may need a 'pocket' cut into the bottom in line with the blade to allow the kerf somewhere to go as your scoring the piece.

    Hope this helps.
    Regards, Robert
     
  5. division 6

    division 6 Master Member

    Trophy Points:
    3,045
    Instead of scoring the plastic and weakening it why not just heat it and pull it over a form for the shape.
    You can make the buck out of a piece of wood.
     
  6. crackerjazz

    crackerjazz Sr Member

    Trophy Points:
    1,525
    I think I can picture what you're doing. You're trying to bevel the edges 45 degrees so you can fold them at 90. Why not cut separate pieces first then bevel them with a tool similar to Rafa's here and glue them together afterwards. I used a similar tool and was very happy with it as you can create any angle.
    http://www.therpf.com/showthread.php?t=134914&page=8&highlight=rafa+tool

    Or -- why not just cut separate pieces the normal way and glue them together without bevelling? With a little putty the seams should be invisible.
     
  7. JiminSTLouis

    JiminSTLouis Sr Member

    Trophy Points:
    1,355
    You need a modeler's scribe which removes material vs. just pushing it aside like a blade will do. It's easy to see how much you are removing with each swipe. A couple of practice pieces and you should know how many swipes it takes to get to the depth you want.

    image.jpg
     
  8. OdiWan72

    OdiWan72 Master Member RPF PREMIUM MEMBER

    Trophy Points:
    3,376
    Re: Question: "Scoring" ABS sheet/ adding a V-groove?

    Thanks for the advice.
    The pieces I am working with are DIN A3 max. Setting up a sanding jig would be too much of an effort for just the one project...anyway nice idea!

    - - - Updated - - -

    Working with 3mm ABS and want clean/ pretty "sharp" edges/ folds, so forming it over a buck is out of question I am afraid :(

    Markus

    - - - Updated - - -

    Since i don´t want to paint the scanner box, I don´t want to use separate pieces glued together....wouldn´t give me the needed results
     
  9. OdiWan72

    OdiWan72 Master Member RPF PREMIUM MEMBER

    Trophy Points:
    3,376
    THAT´s what I need, if I want to do it manually.
    Problem...I couldn´t find this anywhere here in germany!?

    Markus
     
  10. RKS

    RKS Active Member

    Trophy Points:
    341
    If you stick (glue or screw) a piece of a stanley- or exacto-blade or a scalper perpendicular to a block of plastic, you'll have the same scriber but with the added advantage that the hight is now preset at the your desired level, and you can run the block along a guide such as a ruler.

    I did that in the past and it worked well for me.If you want to make it more professional and longer lasting, you can use a piece of brass for your guide block and make the blade adjustable.

    RKS.
     
  11. OdiWan72

    OdiWan72 Master Member RPF PREMIUM MEMBER

    Trophy Points:
    3,376
    Got a pic?

    Markus
     
  12. RKS

    RKS Active Member

    Trophy Points:
    341
    I don't have that thing anymore but if a drawing works for you, I'll make one and mail it to you this weekend.

    In the mean time, this is a very elaborate and fully adjustable version of the same idea:
    http://www.amazon.com/Wheeled-Groover-Grooving-Slotting-Flooring/dp/B00X61BWRA

    Mine is just a blade used with the cutting direction perpendicular to the original cutting direction.
     
    Last edited: Aug 27, 2015
  13. rbeach84

    rbeach84 Sr Member

    Trophy Points:
    1,406
    RKS is suggesting a block with a side-mounted blade, which is clamped in place with a screw (or bolt) & perhaps a washer. You'd probably also want an offset pin (dowel) to brace the blade against the torque of the scoring so it doesn't shift while in use. Not hard to make since you can use a wood block, a wood screw and a nail (for the pin). Good idea, RKS!

    BTW, Tamiya makes a scribing tool that works well. Do you have access to Tamiya paints & supplies?

    Regards, Robert
     
  14. JiminSTLouis

    JiminSTLouis Sr Member

    Trophy Points:
    1,355
  15. James1214

    James1214 New Member

    Trophy Points:
    17
    Re: Question: "Scoring" ABS sheet/ adding a V-groove?

    Depending on how daring you are you can v-groove on a table saw, using a straight toothed blade, set the blade to 45 degrees. This will cut a 90 degree v in the material. With thin materials it is important to attach it to a backer I like 1/2 inch plywood and attach it using double-sided masking tape. I use imperial measurements so I'm not 100% sure but 3mm is like 1/8 of an inch. I've made v-grooved boxes out of 1/8 inch acrylic using this method with good results.
     

Share This Page