We had 2 lots of 26 parts each. All 26 of the lot using 6061-T651 came back in tolerance. 6 pieces of the 7075-T651 lot came back in tolerance but 20 were out by .0004 to .0006 in. This led me to believe that the vendor had stripped this portion of the lot and recoated it leaving the parts...
We had 2 lot of parts sent out to be Black Anodized per MIL-A-8625, Type II, Class 2 with a thickness of .0002 to .0004 in. One lot was our tpical material for the part 6061-T651, the other lot the material was swithced to 7075-T651. We allow for 1/2 of the build-up per surface and the parts...
magic612
We are really trying to avoid hand taping, it is more expensive than scraping. Our gear teeth are well inside the part and are not an issue.
We did use a laser marking machine to remove the powder coat on external surfaces. It worked pretty well but the bores were not so easy to...
magic612,
Thanks for the advice on different masking materials, I'll look into it.
They are round parts of gearheads which are exposed to the shop environment when mounted in the machine. Therefore the outer portion of the unit must be powder coated but the interface surfaces and seal bores...
Thanks for your input.
We are masking round machined parts which need external surfaces powder coated, some with cross drilled tapped holes that need to be masked as well. We have plugs for the tapped holes and are stacking the parts between masks to maximize the number of parts in a lot.
I...
We are currently having problems with masking Electrostatic Powder Coated parts.
Hand masking with teflon tape is too expensive.
We made plastic masks of a material recommended by the Coater but they melted in the 400 deg F bake.
Then we made Stainless Steel masks but where the coating...
We are currently having problems with masking Electrostatic Powder Coated parts.
Hand masking with teflon tape is too expensive.
We made plastic masks of a material recommended by the Coater but they melted in the 400 deg F bake.
Then we made Stainless Steel masks but where the coating...
Kenvlach
Thank you for your response.
We currently do the following process to the material.
1. MATERIAL: 440C ANNEALED SST PER AMS 5630
2. ROUGH MACHINE
3. STRESS RELIEVE FOR 4 HOURS ±10 MIN AT 1100°±10°F
4. FINISH MACHINE
The furnace is a circulating air type.
We do not need the material...
I have currently run into a problem with passivation of 440C. We have a customer who requires this material and passivation per QQ-P-35,Type II. In the spec there are warnings about possible etching when passivating 440C. We had one lot of parts processed without a problem. The next lot came...
optech,
The ID of the part before gear cutting is the top of the tooth after gear cutting. Also note that our gear teeth are very small, ie. .015" high on a 2" pitch circle. The ID is inspected before gear cutting.
I do not understand how you would specify datum targets on a round...
Diamondjim,
Bear with me I am but a lowly designer with but a high school diploma and a 1 year certificate in CAD. However I have had some limited experience with machining and inspection. My concerns are mainly for what is the proper tolerance, what is can be inspected and what can be...
Victor,
Thank you for your response. An essential part of my problem is the establishment of datums, I do not necessraily agree with what has been done historically in the company. I under stand design datums and manufacturing datums and being in a small company I have to work with closely...
My company manufactures predominantly hollow round parts. I am fairly new to the field and have been seeing inconsistencies in historical drawings when it comes to geometric dimensioning and tolerancing. The only answers I seem to get in house is to copy what was done on previous drawings. As...
