Custom Bicycle Frame

Changing object orientation with the Merge command.

If you have multiple objects you're going to merge and they have different orientations,
you can choose which one you will keep by the darker selection color in the object browser.

It also means that the resulting object will take the name of that object.

Changing the object orientation of the frame to the angle of the seat post
is what I want now and it's also the same orientation as the head tube.

Further testing shows it does work, I have so many files for this thing I'm getting a little squirrely.

orientswap.gif
 
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Once you have done the merge and have you're seat post edges aligned
in order to get ready for the Bridge Tool, there's one more thing to do.

Fill in between the stays.

Stay Patch.jpg
 
To test this joint add a Subdivision Modifier level 3.

Make sure you get rid of any creases left over from the Boolean operation.
If it's still not smooth everywhere try Optimize, maybe some points are not welded.

Joint SubDiv.jpg


I replaced the jas file with one properly reoriented.
 

Attachments

  • Seat Tube reo jas.zip
    20.5 KB · Views: 169
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Here's the reoriented jas file, bridged and ready for the next stage.
 

Attachments

  • TrackFrame a jas.zip
    21.3 KB · Views: 171
After doing the five way tube joint this is a piece of cake.
I made all cuts by eye in the two objects, and removed polygons and stray points.

Headjoin01.jpg
 
Then you can Merge the two objects, Bridge them and add a few more edges.

Headjoin02.jpg
 

Attachments

  • TrackFrame c jas.zip
    21.7 KB · Views: 175
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For the downtube, fill the bottom of the headtube first,
then select polygons where the connection will be.

Then use Cover to create new geometry and pull straight out just past the edge, scale flat, cover again
and pull out some more. Then rotate from the top corner into position over the Bottom Bracket.

This is what we're going for:

DowntubeJoin.jpg
 
For the downtube, fill the bottom of the headtube first,
then select polygons where the connection will be.

Then use Cover to create new geometry and pull straight out just past the edge, scale flat, cover again
and pull out some more. Then rotate from the top corner into position over the Bottom Bracket.

This is what we're going for:

{img}
Now that's both an elegant and pretty structure, which is what the very best of real world products possess. Very nice!
 
The downtube should now be 2.0 wide all the way and tapered in the other direction.
To straighten it out make two ring cuts close together at the top and drag one down
along a corner using the Transform Tool set to normal.

straightdowntube.gif
 
The down tube connection to the BB and Chain Stays is next.

StraightDownTube.jpg
 

Attachments

  • TrackFrame e jas.zip
    23.8 KB · Views: 169
Edit: Make the Bottom Bracket 6 sided instead of 8 and make it editable.

Flip the normals of the bottom bracket.

Make a flange on it's edge and Merge it with the frame.

Then weld it into place and sculpt the frame around it.

BBSculpt.jpg
 

Attachments

  • TrackFrame g jas.zip
    27 KB · Views: 168
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I used the Fill Tool to fill in the end that will become the chainstays.

Then Scalpel down the middle of the filled area, select that one edge and Inner Extrude.

I will animate this as it is perfect for this situation but for now here's the result.

ChainstaySplit.jpg
 

Attachments

  • TrackFrame h jas.zip
    27.1 KB · Views: 173
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