KlausDK
18th September 2007, 06:46 PM
Hi,
I have an problem with makeing a MSA on a special go/no-go gage.
The gage is used test if camber of flat substrates are below a specified value.
Camber is defined as the thickness of the substrate + 0.2% of the length of the substrate. if the substrate is 6,4" long and thickness is 0.635, the gap for the camber gage is 0.33 mm + 0.635 mm = 0.995 mm.
The gage is two flat and parralle plates that can be moved so they will have specified gap between each other, the plate are placed at 45° so the substrates has to fall under their own weight through the gap of the two plates.
I have to perform a MSA on this gage, my first problem is when I look at the attribute test in the MSA from AIAG that they easily find a "true" reference, I am not able to find the "true" reference value. As it is only the gage that is able to measure the "total" thickness (thickness + camber). The gage is a go/no-go system, but I can make selection with 0.01 mm difference in gap distance.
I have found 14 substrate which I have selected to be in 3 groupes that pass at 0,850-0,855 0,855-0.860 and 0.860-0.865. The I have marked and tried each of this substrates 20 times and registred the number of passes with a gap setting of 0.860 I have one substrates that do not pass and 11 that pass between 2 and 19 times, and 3 that passes 20 times.
I don't know the "true" value of each and is not able to establish this value by other measureing methods.
I can change the gap, and I can run trials several times with different operators.
Are there any body that has a good suggestion how to proceed.
I have an problem with makeing a MSA on a special go/no-go gage.
The gage is used test if camber of flat substrates are below a specified value.
Camber is defined as the thickness of the substrate + 0.2% of the length of the substrate. if the substrate is 6,4" long and thickness is 0.635, the gap for the camber gage is 0.33 mm + 0.635 mm = 0.995 mm.
The gage is two flat and parralle plates that can be moved so they will have specified gap between each other, the plate are placed at 45° so the substrates has to fall under their own weight through the gap of the two plates.
I have to perform a MSA on this gage, my first problem is when I look at the attribute test in the MSA from AIAG that they easily find a "true" reference, I am not able to find the "true" reference value. As it is only the gage that is able to measure the "total" thickness (thickness + camber). The gage is a go/no-go system, but I can make selection with 0.01 mm difference in gap distance.
I have found 14 substrate which I have selected to be in 3 groupes that pass at 0,850-0,855 0,855-0.860 and 0.860-0.865. The I have marked and tried each of this substrates 20 times and registred the number of passes with a gap setting of 0.860 I have one substrates that do not pass and 11 that pass between 2 and 19 times, and 3 that passes 20 times.
I don't know the "true" value of each and is not able to establish this value by other measureing methods.
I can change the gap, and I can run trials several times with different operators.
Are there any body that has a good suggestion how to proceed.
