Pneumatic Pistons CAD Dimension Discrepancy

Today I got a shipment of pistons in and I noticed that the double acting pistons and the single acting pistons were of vastly different lengths.

However If you look at the CAD models provided by VEX this is not true at least in the same comparison.

http://sphotos-a.xx.fbcdn.net/hphotos-prn1/163361_10151234269680728_945028197_n.jpg

You can see in the CAD the single acting pistons is slightly shorter than the double acting, but in reality the single acting is about an inch longer. Now this really isn’t a huge deal for me but some teams do CAD their robot before building. This kind of error could actually throw off entire designs, in my case It might.

If the download for the Pnuematics kits can be updated this would be great.

Now I say take this carefully as I am using older models, but the parts should still be the same as the part numbers have not changed.

  • Andrew

Make sure you have the right part numbers in your shipment…

If you look at the size of the pistons on this page (double acting) and this page (single acting), they match in all dimensions.

I assure you my part numbers are correct, when I make a 500 dollar order of Pnuematics its not something that I tend to screw up. I’ve noticed this difference and wonder why the CAD model is off that is all, it also appears that the product page is off. I am looking through SMC CAD files now and will report back with my results directly from SMC. I just think this might be a silly oversight.

Now that I have done some research I have downloaded the models from SMC with the correct part numbers, it seems to be some kind of error on their end. The parts I am getting in reality have wildly different dimensions from the CAD (roughly 1.5 inches). Can someone from VEX comfirm I’m not crazy?

  • Andrew

OH—I meant that you should check to make sure that they *sent *you the right part… The buyer rarely goofs up, but the seller does more often than they should. :slight_smile:

This is quite weird. I’d almost be willing to bet that someone gave you the wrong part…

Its the right part number double and tripped checked all Packing lists, POs and parts themselves. There is something wrong with the CAD and its kind of fishy

  • Andrew

These files are straight from SMC showing the same issue.

  • Andrew