Originally posted by cjd
I've actually recently retrograded to hand-building... and here are the tips that I always find myself using:
1. Use at least one vertex per 90 degrees of turning, if not more. Bezier curves are not good at making turns wider than this, and this also makes the "chop method" possible, as that method will only hurt segments that are too long. Also, the included NL track smoother is really good at ironing out the bumps in individual vertexes, but it often completely screws up the shaping of coasters with sparsely-placed vertexes.
2. For shaping elements, try starting with longer segments, ones that will just generally define the shape of the element that you want. Then split it up into smaller vertexes from there, and refine the shaping that way. This generally makes smoothing a lot easier than if you were to go vertex by vertex, which can result in some shaping that you really didn't want, and more difficult smoothing later. Then the only issue left after that is how to smooth out the original vertex... and the AHG or chop methods are very good at this.
3. Make sure that the vertex handles never cross over the track. If you want smooth track, all of the vertex handles should be outside tangents to the curvature. The one exception would be if you are going for authentic Arrow and CCI transitions, in which case having the vertexes directly on top of the track produces the traditional jolt going into them.
4. In general, you should make the length of the vertex handles proportionate to the length of the segment that they define. If there is a long segment before the vertex, use a long handle. If it's short, use a shorter handle. This is the general rule for getting the right flow.
5. Vertexes that are equal distances apart from each-other make smoothing a lot easier. The included NL track smoother can either be your best friend if you use proportional vertexes, or completely mess the coaster up if they are too variable.
6. This is what I call the "chop method." Basically what you do is isolate a bumpy vertex by cutting the segments immediately before and after that vertex in half. Then delete the original vertex. This will re-shape the track that it was on. Then re-split the resulting long segment, and delete the two vertexes that were created by splitting the segments in the first place. Run this resultant new vertex, and the two vertexes immediately before and after it, through the track smoother, and the result is usually a much smoother vertex. (Once again, this only works when vertexes are relatively close together to start with.)
7. Use AHG with a 0-value heartline, all black, and a low vertex #. What this will do is take your element and re-shape it with equidistant vertexes, but not so many that you can't still work it by hand. Sometimes this solves smoothing problems all by itself.
8. Experiment with vertex handles, and look at how various changes in their length/placement relative to the adjacent track impacts the flow of the vertex. Take mental notes, so that the next time you see a troublesome bump, you can observe the nature of that bump's flow and know what kind of vertex-shaping errors traditionally cause a bump to behave like that.
9. Look at the shaping of real coasters, and how they flow. The more you know how real elements are shaped, the easier it will be to make properly-shaped elements in NL. Don't guess. Do some research.
10. Try downloading a few hand-built coasters that are already smooth, and take a look at how they did it. I recommend some of the old coasters on this site, from Hansixx, GFA, and the like, in the days before Elementary and AHG, and see how they are shaped. This was a huge help for me when I was getting started.
11. Try making the shaping of your elements either close to circular, or continually tightening-widening. If a turn has flat spots or pointy spots, it will result in g-spikes and what we call "pumping."
12. Practice, practice, practice. There is no better method.
I've actually recently retrograded to hand-building... and here are the tips that I always find myself using:
1. Use at least one vertex per 90 degrees of turning, if not more. Bezier curves are not good at making turns wider than this, and this also makes the "chop method" possible, as that method will only hurt segments that are too long. Also, the included NL track smoother is really good at ironing out the bumps in individual vertexes, but it often completely screws up the shaping of coasters with sparsely-placed vertexes.
2. For shaping elements, try starting with longer segments, ones that will just generally define the shape of the element that you want. Then split it up into smaller vertexes from there, and refine the shaping that way. This generally makes smoothing a lot easier than if you were to go vertex by vertex, which can result in some shaping that you really didn't want, and more difficult smoothing later. Then the only issue left after that is how to smooth out the original vertex... and the AHG or chop methods are very good at this.
3. Make sure that the vertex handles never cross over the track. If you want smooth track, all of the vertex handles should be outside tangents to the curvature. The one exception would be if you are going for authentic Arrow and CCI transitions, in which case having the vertexes directly on top of the track produces the traditional jolt going into them.
4. In general, you should make the length of the vertex handles proportionate to the length of the segment that they define. If there is a long segment before the vertex, use a long handle. If it's short, use a shorter handle. This is the general rule for getting the right flow.
5. Vertexes that are equal distances apart from each-other make smoothing a lot easier. The included NL track smoother can either be your best friend if you use proportional vertexes, or completely mess the coaster up if they are too variable.
6. This is what I call the "chop method." Basically what you do is isolate a bumpy vertex by cutting the segments immediately before and after that vertex in half. Then delete the original vertex. This will re-shape the track that it was on. Then re-split the resulting long segment, and delete the two vertexes that were created by splitting the segments in the first place. Run this resultant new vertex, and the two vertexes immediately before and after it, through the track smoother, and the result is usually a much smoother vertex. (Once again, this only works when vertexes are relatively close together to start with.)
7. Use AHG with a 0-value heartline, all black, and a low vertex #. What this will do is take your element and re-shape it with equidistant vertexes, but not so many that you can't still work it by hand. Sometimes this solves smoothing problems all by itself.
8. Experiment with vertex handles, and look at how various changes in their length/placement relative to the adjacent track impacts the flow of the vertex. Take mental notes, so that the next time you see a troublesome bump, you can observe the nature of that bump's flow and know what kind of vertex-shaping errors traditionally cause a bump to behave like that.
9. Look at the shaping of real coasters, and how they flow. The more you know how real elements are shaped, the easier it will be to make properly-shaped elements in NL. Don't guess. Do some research.
10. Try downloading a few hand-built coasters that are already smooth, and take a look at how they did it. I recommend some of the old coasters on this site, from Hansixx, GFA, and the like, in the days before Elementary and AHG, and see how they are shaped. This was a huge help for me when I was getting started.
11. Try making the shaping of your elements either close to circular, or continually tightening-widening. If a turn has flat spots or pointy spots, it will result in g-spikes and what we call "pumping."
12. Practice, practice, practice. There is no better method.
Thank you so much CJD! This is the best advice I've gotten so far! I appreciate this so much!!