Author Topic: Square-to-Round is Missing Seam/Connector Allowance at Rectangular Corner  (Read 326 times)

0 Members and 1 Guest are viewing this topic.

Offline jaysomlamTopic starter

  • Full Member
  • ***
  • Posts: 240
  • Country: us
  • Gender: Male
We are having a problem with setting up the seam and connector allowance for our square-to-rounds.  We expect the area where the seam meets the rectangle connector (TDF connector) to have some material available.  Then when the two halves of the duct body are spot-welded together, there will be material to be spot-welded at the rectangle connector allowance.  Unfortunately, when we look at the duct body on the screen, we find that the material is missing.

Attached please find two pictures showing what I have expected to see and what we actually see in CAMduct.

Please let me know the proper settings to fix this problem.  Thanks a lot for your help in advance.

Jaysom

Offline cadbob

  • Premier Member
  • *****
  • Posts: 2621
  • Country: us
  • Gender: Male
    • Cannistraro
It is tough to run a Square to round through the TDF Roll Formers, quicker just to make DuctMate or if the shop has Angle Mate Machine to make your own Ductmate style Flanges
Live like you golf. Don't forget to follow through

Offline cadbob

  • Premier Member
  • *****
  • Posts: 2621
  • Country: us
  • Gender: Male
    • Cannistraro
To add to post, if you really, really wanted TDF, you could go to OPTIONS and change CrossBreak to (4) which I highly would not recommend if you want to stay friends with the shop guys! :)
Live like you golf. Don't forget to follow through

Offline TruDuctInputter

  • Active Member
  • **
  • Posts: 36
  • Country: us
  • Gender: Male
A few thoughts:
How are you going to form the TDF connector when the square to round is 2 piece? You can't put it through the wheels when it's 2 piece because it'll run over itself. If you want to run TDF on square to rounds, i think that it needs to be 4 piece. (That's what I've found and is how we do it at our shop)

If you want that meat to be added on a 4 piece square to round, it requires the following: 1. Item option "v notch regular extension" needs to be set to "yes." 2. Your seam needs to have the the "vee depth male" set to "full allowance." 3. Your connector needs to have a notch set up for it that doesn't have the "notch out" box selected.

Offline TonyD

  • Full Member
  • ***
  • Posts: 106
  • Country: us
  • Gender: Male
Hopefully this works out for you. This is recommended for a 4-part sqr2rnd with straight only. Using these options with any other layout creates development issues.
Tony De Lara
Project Engineer
Omniduct

Offline jaysomlamTopic starter

  • Full Member
  • ***
  • Posts: 240
  • Country: us
  • Gender: Male
Thanks for the replies that I have received.

Based on the suggestions that I have received so far, I can put the "meat" back using the following settings in the Options page of the item properties of square-to-round:
1.  V-Notch Rectangular Extension: Yes (it was No)
2.  Seam Cut Back: 0.5 (it was None)

Unfortunately, I am missing all the notches (see the attached picture).

I have two questions and I hope someone can answer:
A.  What is "Seam Cut Back"?
B.  How can I put the notch back?

As of how our shop fabricate square-to-rounds that have TDF connector, I don't work in the shop; therefore, I don't know the exact details.  Based the what the shop manager told me, they need to use a roller machine to bend the metal to form TDF for square-to-rounds (instead of using a TDF machine that would have been faster).  This is still well worth the effort because the TDF connection is strong, and is easy to install in the field.

Jaysom

Offline TonyD

  • Full Member
  • ***
  • Posts: 106
  • Country: us
  • Gender: Male
The options layout I showed originally is only applicable with a 4-part sqr2rnd with "straight" on the rectangular side. If I apply these options to a sqr2rnd without straight and in 2-part construction (girth split = 2) I will get the same development you are showing. Unfortunately, this is the only possible combination of settings in camduct that will give the desired seam extension when utilizing straight on a sqr2rnd.

I have previously made mention of this on the Autodesk Fabrication Idea message board and to our service vendor but has not warranted being implemented so far. It may get recognized as a needed correction if more users were to vote on my post or bring up the topic.
Tony De Lara
Project Engineer
Omniduct

Offline jaysomlamTopic starter

  • Full Member
  • ***
  • Posts: 240
  • Country: us
  • Gender: Male
So far, I can get the missing material _and_ the notch back in the area where the seam meets the rectangular connector by setting these options:

In Options Specific to Square-to-Round:
1.  V-Notch Rectangular Extension: Yes (it was No)  <-- This brings back the missing material
2.  Seam Cut Back: 0.5 (it was None)  <-- This seems to be related to bringing back the missing material (not sure)

In Options for all fittings (Pattern Options --> Notches):
-   Notch for Connector Split: None (it was "Notch Out") <-- This brings back the missing notch
This option is for all fittings.  I am hesitate to recommend changing this option because I don't know exactly what this option is supposed to do for all the other fittings.  So far, I don't see any negative effect on other fittings after this change though.

But the result is still not exactly what we want because the notch is not a V-notch.  It is more like a straight notch.  This may or may not be what the shop can accept.  We will see...

Jaysom

Offline JAA

  • Full Member
  • ***
  • Posts: 135
  • Country: us
  • Gender: Male
It is interesting to see how other shops/regions want fittings set up for fab. Back when I ran our shop, if a downloaded sq to rnd slipped thru edit with a full dimension connector allowance-it went to the shear and got a ductmate or outside tap etc. added after it was formed. Definitely not going thru our roll forms.
Unless it was a 4 piece and exposed and specifically requested........ ;D
Intel Core i7-4771 CPU @ 3.50GHz, 32GB RAM
Nvidia QUADRO M4000 8GB
Building Design Suite Premium 2020, CADmep & CAMduct 2020