Techdraw drawings need repeated creation

[DaveGray65]

In the attached Freecad file, the Techdraw drawing does not reflect changes to the 3D model. Two side holes have been removed and a crossing hole has been added. Unfortunately, it is normal for Techdraw to not reflect changes to the 3D model.
The only way that I have found to update the Techdraw drawings when this happens is to laboriously delete the dimensions in each view, then the views, then the projgroup, annotations and template then the page and finally recreate the Techdraw drawing from scratch.
Is there a more convenient way of updating the Techdraw drawings to incorporate 3d model additions and deletions?
I have Freecad version 0.17 in its initial “official” release.

OS: Windows 8.1
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.13522 (Git)
Build type: Release
Branch: releases/FreeCAD-0-17
Hash: 3bb5ff4e70c0c526f2d9dd69b1004155b2f527f2
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: English/UnitedKingdom (en_GB)

[wandererfan]

In the attached Freecad file, the Techdraw drawing does not reflect changes to the 3D model.

Your ProjectionGroup and its secondary Views have no Source object. If you update the Source property (using the ellipsis on the right) for the Group and its Views and press recompute button, the Views will appear.

GroupMissingSource.png (29.05 KiB) Viewed 1002 times

ItemMissingSource.png (28.71 KiB) Viewed 1002 times

Before seeing your file, I would have said it was impossible to create this situation in the Gui.

I would appreciate it If you could provide step by step instructions on how you create drawings. If there is a way to produce a View with no Source, I will need to correct that.

[DaveGray65]

Thanks for your reply but unfortunately I can’t find a Recompute button. Do I need to download a Techdraw update?
When I click the ellipsis on the “Source” lines, I get lists that include things like views and dimensions. One or more of the items in a list can be selected but when OK is clicked, nothing appears to happen.
I’ve tried reproducing the effect with a simple part without success.
Frustratingly, if I open the file attached to my first post, the dimensioned Techdraw views have been replaced by extreemely small squares of dotted lines. The annotations remain.
To create that attachment I started with the file that is attached here, I deleted Pocket001 and its Fixing hole 2 sketch. I then deleted Pocket, mapped the fixing hole 1 sketch to its new surface, renamed it as Pivot hole, changed the diameter and recreated Pocket.

[chrisb]

Thanks for your reply but unfortunately I can’t find a Recompute button. Do I need to download a Techdraw update?

It's the general recompute:

[wandererfan]

I deleted Pocket001 and its Fixing hole 2 sketch.

In "Feed tank Cover v1.2.FCStd", Pocket001 is the Source object for your drawings. When you delete it the Views have no way of knowing what to draw. The Views will not update themselves in the absence of a Source, so your images stay on the page during the current session. Once you do a save/restore, the absence of a Source becomes a problem since there is nothing to draw and you only see the empty frames of the Views.

[DaveGray65]

With the guidance from both of you I’ve been able to fiddle around and work out how to do it.
Thank you both

[NormandC]

Hi Dave,

Instead of using the last feature in Body as source for the TechDraw views, you should select the Body itself. That way, if you delete or add features to it, the ProjGroup will always update; be aware though that some dimensions may disappear if the geometry changes too much; it is best to wait after the design is more or less finalized before adding dimensions.

[DaveGray65]

Thanks NormandC. I'll try that next time.