Reverse Engineering with OS

billy2

How do you design a cover for something you have no prints, drawings or models?
I don't normally post stuff like this but the results were much better than I expected I thought others might benefit from this simple technique.

The secret sauce was to use OS to triangulate these holes and find their locations accurately. I was really surprised at how accurate the hole locations match.

original note



Simple Technique
So, I wanted to design a new counter shaft cover but I have no idea where these holes are located:


Working with the old cover, I placed drill bits in the existing holes and zero'd out my $9 harbor freight calibers:


Because I zero'd the calipers out on a drill bit diameter, the number shown is the center line distance between the holes:


You have to measure each hole relative to each other:




Now for the OS stuff
I made a sketch and created holes with the dimensions I measured:


Then I added the new cover shape:


This is the new waterjet part setting on top of the old cover with the bolts running through both. Now the hole clearance for the bolt is really tight, yet everything fits. I was figuring on opening up the holes in the the new plate to 7mm to allow for mis-alignment of the holes, but no need for that!


Bolts fitting through new plate and old cover:


Anyway, $9 worth of CMM tools and I'm done:




Round II Stylized
Ok so I'm not done, I'm cutting more waterjet parts tomorrow and came up with these stylized changes.
-added bolt boss accents
-c'bored bolt heads
-added sub-cover

brucebartlett

Good Stuff. How did you get your file out as there is no dxf export yet.

I'd like a quick dxf export, into a tab, possibly even linked for geo changes and a direct email to supplier for this kind of work.

Bruce

Ben_

That is awesome @bill‌...
@babart77‌  there is no DXF export yet that I am aware of. I export a parasolid and import into SW and then DXF. However word on the street is that the drawing package is almost there and soon we can do the DXF thingy....

billy2

I showed my waterjet guy how to use a step file but he prefers DXF (old school). So like Ben says, import it & export it. You have to remember to convert units to inches before exporting a DXF. I personally wish the world would stop using DXF because converting between inches & mm is painful for a large cutting project and every part's units has to be toggled. With step, the units are contained in the format, with DXF a unit could either be inches or mm's. I'm not a fan of DXF/DWG because it's unit-less.

Maybe I'll take a stance and send him step files and improve the world one supplier at a time.

lougallo

@ben we are striving to have drawings by launch but I think getting dxf out of sketches might harness an export option. We are still figuring thugs out but we understand the importance to get profiles and layouts in dxf for water jet, laser, router operations. Good stuff @bill

kevin_quigley

Lou, no drawings, no launch. It is that simple (I know its not your decision but those that do are watching).

lougallo

@KevinQuigley I am not sure if the message is getting lost here but Drawings WILL be in the product.  We understand the importance of drawings and we will get the bits out to everyone to test as soon as it is to our standards. Hang tight until then.

kevin_quigley

I know drawings are coming, but I was refering to the product launch feature set. I honestly believe that launching Onshape without a workable drawings feature set would be a mistake. My opinion for sure, and I know a lot less about the market than most here.

lougallo

@KevinQuigley Yes the first impression when we open business officially will be important and our feature set will include all the important pillars, one of which is Drawings.  Personally I wish we were in an age when drawings were a thing of the past but the reality is there are too many parts of the business aspect of engineering that rely on prints.

pete_yodis

LouGallo said:

@KevinQuigley Yes the first impression when we open business officially will be important and our feature set will include all the important pillars, one of which is Drawings.  Personally I wish we were in an age when drawings were a thing of the past but the reality is there are too many parts of the business aspect of engineering that rely on prints.

@LouGallo Does this mean you guys are considering support for documenting the models based on ASME Y14.41... Model based definition, model based design, etc...?  That would be fantastic.  I share the angst about 2D drawings -  a necessary evil but not nearly as efficient as it could be.

joe_dunne

KevinQuigley said:

I know drawings are coming, but I was refering to the product launch feature set. I honestly believe that launching Onshape without a workable drawings feature set would be a mistake. My opinion for sure, and I know a lot less about the market than most here.

We share your opinion

Joe