shape intersection with complex object fails

[tve]

I have a complex object and am trying to cut out a section so I can print just that to test the fit, but the intersection fails. Here is a screen shot that shows the object 3 times:

• the colorful version to the left shows the individual parts that are fused
• the light grey version to the right is the fused final object
• in the center is the final object in light green and a box I want to intersect with in light blue

But when I perform the intersection I get:

Somehow this cylinder piece is the intersection between the box and one of the cylinders that make up the complex object. Everything else is missing...

Model source: https://studio.replicad.xyz/workbench?code=UEsDBAoAAAAIABiL9lbruTHXfwUAAIQPAAAHAAAAY29kZS5qc41XW2%252FbNhR%252B96848F6kVJYdF8HWAh2WS7s9bGjQpkvaog%252BMRFlaaFKlqDhGkB%252B0v7FftsObRMl2tiCGeTnX73yHpOdz%252BFRvKp6ftXm%252BBfLAKKxFyxUUQgJh7bri7RrWpFEJ%252FHk8mc%252FhXNRbWa1KBf%252F8vVwsXyZwVQrZKMrhXnB4W2V3lE8m8yNYMXFLGEhasyojORzNcfUIflHbmua0gEfQI1FAta6FVNHUS05jeBqoTTLBGwUS3nTLfq3IFK4uJ%252FRB2wC7iNZJy9QlkWTd4PbjBABDX5OKmxxxqr8uKvIajl8lbvo75ThdLGCurfrVa8LYa3iZWBMl4bnRtwOj8mOgYZcvRRMsa71aNJWqEB%252FCBF%252F5IKz0KV8x%252Bhp%252BOjGSRM9ACWgYwTpYEWjrDZF5Y4NoGKX3RqYULO%252FLRB%252BUbBv0gmJWxsZ30sdnl21O1p8qsWKcNg1gJTa4AUQiA3L4BLUURWUCba%252BrXJUandRqbfRca0S3QimxxmE81LigtdF4aeRLaiijFZoqp82u%252FJWOA%252BXTPWE5MROex0BJyleqpLxCPHGXUTVXsjLwoQgOXT1d5ZpM0o3GjInsTmM2hEvvGj6cJH76vij6eERRNBTpJjHXjHJF5eRpMilanpmyZlhWeiol2UYkRmZLqlqJ1U7XpI4ogzc%252FA2WpkYpipPfEE9ZRFTpLmqRRHRvOWjabrkTmo607er5l2K5URnXqKIzFXSZgp5hynKIigBSKKBq9WiTwFT%252F6%252FxsOZ8duHKc6K2YwBGyLz%252BimaoyqkoQj%252BRT9MnQSGw2yBcERxpvPUCND6aSL01G1i1RgWyORogCbr8aBb0WnkLmUbNz%252FkWXXdy7PLlO%252FZbppmDR%252Bm7x3kp7dmKyRk0zTk21t09Hc91vsfByEJNmPicuyaWtd5Pkd3W7INsjvjDT0TDxEQT6%252BhKOKekfpOJJoFihbDZ1vnHjnd1zc%252BrH1%252BrEuqaR9BkfYzSfOshHKJdmcVzJju0LNHVVZ%252BZ5f6vyiOJX0XrB7Gn09ThaJRnZo5VKwrWn0kaEElov%252Fa%252BygJTiC3lbWqshKfqCZMu3fSwYoxmkPnSbEEN5nY%252FId82wJjNTAKLwI%252BYpB%252F0FUmWaiGXIVN2R68fbX5YfTi1gT7lvsXHWOPncaeLMcbPCBc8d7S3tTFyMPjfBtV4uKqwaZ3newvR3MyY1tXKf2EMc8lhhknfaXx0jD3A5Www6f09BH629i%252F5Hmj%252BE5sjkw%252FWI5rl6wOV%252B%252BcIp4YOtOj0fRdY76rutuxyTMeeDTwWxvlsg3oGabP3cO2cTsj5MOvaRDpSNQSCFfuh4pe%252BbsUmAWVqc%252FEnREHaZa11x3Nn%252B8BHV8CADHu0%252Bm70hG31ms47RyVJ%252FefJnqgyMtcCeyThJ4bHn1vcVnCd6R9KmHtDd5sOmwHPb2PRpWcTaq4qCG4wa0US0Hjq9E3fkdH1MBIgNwRwKHj%252Bt97mc%252Bk0EYGIMNJmWiUNeVKiOHisbQ0AU5aF8dWBjddQgtvoTF7V%252BIVn%252Bv41vr2ctSR564dvVIJto3nhBD%252B4pqtlP7gsDMspLiI6eoFD7UkC32hViNnoguIVT9iJpI4p1GWS4G%252FWEONAuI5vhiUF2zsq8CsxP9iQcOT03qCIB%252FEoWkdQENBZCu%252BObSKUZBxN2LaicdXaRducBKYNuA6V5s9oXyCE1JamS%252FluqyuYnw1wFe%252BZyscWuKe8iRTDAhcfZDUVD8m8JTMjKBVQxtzIZGcDewIlButceIJcFhM3Y%252FMHTL2j1mbL0Om7H7gZmVpJTvseMPnGdMeZHA2pYyJjbTsTWk1GE7uBniw6r7PXn5UvdabiFQrVtZs2d0kSY76rgWWMAfuZTtB9aResfA6YAj5pUZQvoNf0T8C1BLAQIUAAoAAAAIABiL9lbruTHXfwUAAIQPAAAHAAAAAAAAAAAAAAAAAAAAAABjb2RlLmpzUEsFBgAAAAABAAEANQAAAKQFAAAAAA%253D%253D

To see the result of the intersection select only the "testSect" object in the viewer.

[sgenoud]

There was two problems with your code! The main one is that you used makeCompound when you should have used some fusing. makeCompound keeps the different parts separated - but you want to fuse them into one. When you do an intersect on a compounded shape it gets confused.

There is also an issue with your knob - when you revolve your shape it creates some weird self intersections. It works with the sphere for instance.

Here is the code with my modifications.