Troubleshooting CAD files

As you work with CAD files for your engineering drawings, you may come across artefacts that just don't look "quite right". There can be various factors contributing to the odd preview in RedEye and this article highlights a few common themes that you can follow the traces to troubleshoot at the first pass.

Refresh Artefact Preview

If you think the artefact preview is not showing the true representation of the drawing, the first thing you can do is use the "Refresh Preview" tool in artefact page. This tool will trigger RedEye's CAD tool to re-render the preview. So if you have any Xrefs, plot styles, fonts and etc added after the preview was created, doing so will bring all of the added entities into the preview.

Make sure that you refresh the browser/tab to view the refreshed preview.

Refresh DWG layout

CAD files, more likely or not, contain more than one layouts in the file (think model space and paper space). Refresh DWG Layout will run the RedEye CAD tool against the drawing and present to users all of the valid layouts within the files. User then can select the appropriate layout and paper settings they want the preview to render. This is a good tool to use if the drawing's plot setting's set up incorrectly.

Plot setting

A good rule of thumb is RedEye preview should match with the output PDF file when being plotted from CAD software NOT how drawings look like in CAD software.

Does the drawing have the correct paper size selected?

Does the drawing have the right plot area set up?

Check plot options, orientation, plotstyle

Elements outside of the title block

When your title block is squished to a corner, big or small, this is usually caused by Plot Area being set to "extent" but drafters have left elements in the layout outside of the title block. As a result, AutoCAD/CAD tool will zoom all the way out to include all elements in the "extent" as the preview. Unused elements outside of the title block should be deleted

Latest active layout

RedEye default renders the "Latest active layout" that is the layout last viewed before the CAD file is saved. Common issue of this is if drafters last touched the model space before they save the CAD file, RedEye will render the Model space as the preview instead of the paper space as intended. 
This can be fixed by opening the CAD file and save it when user's active in the paper space. Or utilise the Refresh DWG Layout tool in point 2 to get RedEye CAD tool to render the correct space.

Plot style (missing)

First check the "report" section of the artefact to see if there are any plot styles missing. It's important to note that drawings can still be missing plot styles if not reported (report being resolved and so on). If the drawing is missing Plot Style, the thickness and colour of the elements in the drawing may appear to be off (too thick, too thin or wrong colour)

Xref (missing)

Same as above, first check the "report" section of the artefact. to see if there are any Xrefs missing. Characteristics of missing Xref is that drawing previews will have element missing (see small or large area of the drawing being blank). Missing elements sometimes are replaced by file paths of the Xref files.

Frozen/disabled layers

Echoing the above
A good rule of thumb is RedEye preview should match with the output PDF file when being plotted from CAD software NOT how drawings look like in CAD software.
Frozen or disabled layers are visible in AutoCAD when drafters are drafting drawings. They do not appear in the plotted PDF due to the mentioned settings hence do not appear in the RedEye preview.

OLE Objects

Unlike Xrefs, OLE Object is a technique to embed objects into drawings. The format of OLE can vary from images to Microsoft Office elements to PDFs. Not all OLE embedding technique is supported in RedEye. Please contact your Customer Success team to obtain a guide on OLE Best Practice.

Measurement units

Run a "UNITS" command in AutoCAD and check that the units set for your drawing are correct. This is important because plot styles, units and plot setting go hand in hand. 0.15mm line weight in a drawing that's 200m in width would be nearly invisible. Misaligned settings can create drawings that are Km^2 in size which would cause RedEye to timeout.

Run an Audit command

AutoCAD's built in "AUDIT" command checks the file's integrity and offers the option to auto fix the errors for users. Drawings with critical errors sometimes fails to upload to RedEye.

Run a Purge command

AutoCAD's built in "PURGE" command allows users to delete unused blocks in the drawing. Too many redundant blocks in the drawing can cause the file size to bloat up and cause upload issues.