At SolidWorks World 2008 (SWW8) we saw confirmation of a rumor. SolidWorks 2009 would have the capability to add slot holes to parts. This is a long sought after function that some would say has been missing along. As demonstrated, the slot hole was not a special feature. It was a sketch tool! Some may not initially like this, preferring slot holes to be their own discrete type of feature. Others may prefer creating slots with a special sketch tool.
The SWW8 demonstration showed the presenter starting a sketch, picking the slot tool. This allowed him to draw just a construction line with two LMB clicks. The slot form automatically formed as though it was a capped offset from the initial construction line. One more click set the sketch entities for the slot. It appeared to be easy and painless. I presume dimensioning of the slot within the sketch would be similar to current methods for similar sets of entities in the current version of SolidWorks.
The advantage to the slot function as a sketch tool is that user can actually create either an extrude or cut-extrude with the same tool. So, not only are slot holes supported, but so is their opposite and positive counterpart. As long as SolidWorks allows the user to dimension the slot hole on the drawing with the Hold Callout function, I do not have any major issues with this. A mild criticism is that this method is a kin to how holes were made in the earliest SolidWorks versions, long before Hole Wizard, and presumably even before those “legacy holes”. Perhaps this is just the first volley in a long series of improvements as we work our way to a Slot Wizard? Maybe not.
However, some users might be expecting slot holes to be a feature of their own. I cannot fully imagine how SolidWorks might accomplish this. Maybe special one-off sketches are required, with sizes regulated with a Property Manager, similar to Hole Wizard holes. Thinking of this, I can imagine that it would be nice to have some feature level control over slots so that they can be automatically sized when associated with a particular fastener within an assembly.
As far as dimensioning for slot holes on drawings, I did participate in early questionnaires regarding how this should be done. I dutifully pulled my advice from ASME Y14.5M-1994, with special attention to Fig 1-35(b). I also stated that I preferred centermarks to be at the center of slot by default (again referencing Fig 1-35(b)). This will allow the quickest and simplest scheme to specify a slot hole. This brings to mind a question. If Hole Callout does callout slot holes this way, what will it do for extruded shapes that use a slot sketch? There is no standard for this in ASME as far as I can tell, other than just directly dimensioning the feature.
There is one major point of concern. How does this function translate into model assemblies? Does SolidWorks 2009 quickly identify the slot hole center when smartmating a fastener at that location? Right now, I always groan when I have to mate a screw to a slot because so much has to be done directly by me. Update: something as simple as a temporary axis at the center of slot hole will be enough to address this issue, I believe.
One minor question of mine is how would slot sketch entities be handled within a sketch? I think it would be best if they are recognized collectively as a slot, but can also be “exploded” into individual entities when other shapes based on the initial slot are desired.
I am looking forward to regularly using the new Slot functionality. It promises to be a great timesaver that is well overdue.
