Cutting out pieces

Discussion in 'Tips, Tutorials & Tools' started by CharlieB, Apr 13, 2006.

  1. CharlieB

    CharlieB Member

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    I know this has been covered before, but I can't remember where I read it: when cutting out pieces, do you either cut to the line, to the inside of the line, or split the line?

    I tried gluing some body panels together after rolling them and since I cut to the line, there were several gaps that I couldn't get to lay flat.

    Thanks for the nelp...CharlieB
  2. CharlieB

    CharlieB Member

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    I know this has been covered before, but I can't remember where I read it: when cutting out pieces, do you either cut to the line, to the inside of the line, or split the line?

    I tried gluing some body panels together after rolling them and since I cut to the line, there were several gaps that I couldn't get to lay flat.

    Thanks for the nelp...CharlieB
  3. Jim Nunn

    Jim Nunn Member

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    CharlieB

    Yes. . . .

    Each designer has a preference but most of the time I cut to the center of the line. This is not a hard fast rule on a lot of the newer commercial models you may find that you will need to cut to the inside of the line.
    You also have to consider the complete assembly. As an example lets say you are making a cylinder 3/8 inch (10mm) in diameter and the cylinder has two internal bulkheads. Most older models have cut lines around .5 mm wide. The difference in the circumference on these bulkheads between cutting on the inside verses the outside of the line is 3.14 mm almost 1/8 inch. On the new computer designed kits the cut lines are a little less then .25 mm (.008 in) this still works out to a difference in circumference of 1.25 mm a little less then a 1/16 of an inch.

    I would suggest that if you making a fuselage that you test build a section starting by cutting on the center of the line and dry fit the parts. If the skin shows a gap then trim the parts to the inside of the line.

    I use Illustrator to make detail parts and I have noticed that the out line is centered on the edge of the part. So cutting to the center makes sense.

    Jim Nunn
  4. Jim Nunn

    Jim Nunn Member

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    CharlieB

    Yes. . . .

    Each designer has a preference but most of the time I cut to the center of the line. This is not a hard fast rule on a lot of the newer commercial models you may find that you will need to cut to the inside of the line.
    You also have to consider the complete assembly. As an example lets say you are making a cylinder 3/8 inch (10mm) in diameter and the cylinder has two internal bulkheads. Most older models have cut lines around .5 mm wide. The difference in the circumference on these bulkheads between cutting on the inside verses the outside of the line is 3.14 mm almost 1/8 inch. On the new computer designed kits the cut lines are a little less then .25 mm (.008 in) this still works out to a difference in circumference of 1.25 mm a little less then a 1/16 of an inch.

    I would suggest that if you making a fuselage that you test build a section starting by cutting on the center of the line and dry fit the parts. If the skin shows a gap then trim the parts to the inside of the line.

    I use Illustrator to make detail parts and I have noticed that the out line is centered on the edge of the part. So cutting to the center makes sense.

    Jim Nunn
  5. CharlieB

    CharlieB Member

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    Jim:

    Thanks for the advice. I'll give it a try tonight.

    CharlieB
  6. CharlieB

    CharlieB Member

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    Jim:

    Thanks for the advice. I'll give it a try tonight.

    CharlieB
  7. Bengt F

    Bengt F Active Member

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    Cutting Edge technology

    Hi CharlieB,

    I always cut as close to the line as possible. I then examine the cut part closely - if I see any trace of the line (and it if it will show after a dry fitting), I ususally scrape the remains of the line down very gently with the edge of a scalpel. When I do this, I hold the part up so that it will give way a bit to the scraping, and I scrape in a motion from the part outwards. This technique applies only if the part is white or near-white, otherwise you would scrape off the colour. I have found that this works especially well with heavy matte photo paper stock with a kind of chalk-white surface. With glossy paper or dark coloured areas, I wouldn´t recommend it, though. A light touching up with the proper water colour or marker pen on the cut edge is what I prefer to make it as invisible as possible.

    If the contour lines are broad - as is sometimes the case with models from FG - you could end up with smaller fitting problems. But so far I´ve been able to correct them by adding a little material before doing the final end cut.

    This is an easy way of removing unwanted lines or dotted fold lines from the finished model, if executed with care.

    Good luck!
    Bengt:grin:
  8. Bengt F

    Bengt F Active Member

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    Cutting Edge technology

    Hi CharlieB,

    I always cut as close to the line as possible. I then examine the cut part closely - if I see any trace of the line (and it if it will show after a dry fitting), I ususally scrape the remains of the line down very gently with the edge of a scalpel. When I do this, I hold the part up so that it will give way a bit to the scraping, and I scrape in a motion from the part outwards. This technique applies only if the part is white or near-white, otherwise you would scrape off the colour. I have found that this works especially well with heavy matte photo paper stock with a kind of chalk-white surface. With glossy paper or dark coloured areas, I wouldn´t recommend it, though. A light touching up with the proper water colour or marker pen on the cut edge is what I prefer to make it as invisible as possible.

    If the contour lines are broad - as is sometimes the case with models from FG - you could end up with smaller fitting problems. But so far I´ve been able to correct them by adding a little material before doing the final end cut.

    This is an easy way of removing unwanted lines or dotted fold lines from the finished model, if executed with care.

    Good luck!
    Bengt:grin:
  9. CharlieB

    CharlieB Member

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    Bengt:

    Thanks!

    CharlieB
  10. CharlieB

    CharlieB Member

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    Bengt:

    Thanks!

    CharlieB