Tmoose
Mechanical
- Apr 12, 2003
- 5,628
We just received three 8000 lb cast steel hubs from a supplier.
Each hub has a 28" long machined Ø760mm/Ø29.92" bearing bore.
Our incoming inspection determined the bores' sizes and roundness are acceptable using large inside micrometers ( "stick mikes" ).
As the hubs were being moved by crane to the assembly area, folks noticed that, when the hubs were back lit by the shop lights, the bore machined surfaces looked mighty suspicious.
What looked like Small divots were visible. There were even some entire areas with a rippled uneven appearance.
It became pretty obvious that the bores had received a great deal of hand finishing after machining to make a uniform looking surface.
We are trying to come up with a DIY method of quantifying the surface defects to a useful degree.
The shop has determined that spraying a paint "guide coat" and then gentle block sanding to reveal high and low spots is out of the question.
Any kool ideas ?
thanks,
Dan T
Each hub has a 28" long machined Ø760mm/Ø29.92" bearing bore.
Our incoming inspection determined the bores' sizes and roundness are acceptable using large inside micrometers ( "stick mikes" ).
As the hubs were being moved by crane to the assembly area, folks noticed that, when the hubs were back lit by the shop lights, the bore machined surfaces looked mighty suspicious.
What looked like Small divots were visible. There were even some entire areas with a rippled uneven appearance.
It became pretty obvious that the bores had received a great deal of hand finishing after machining to make a uniform looking surface.
We are trying to come up with a DIY method of quantifying the surface defects to a useful degree.
The shop has determined that spraying a paint "guide coat" and then gentle block sanding to reveal high and low spots is out of the question.
Any kool ideas ?
thanks,
Dan T