17-4 PH GO/NO GO gauge 4

[DrDroids]

Hopefully this question is in the right place. I was wodnering if any one could provide me with some advice on what type of steel I should use for some GO/NO GO gauges I'm having made. I currently selected 17-4 PH steel but I'm wondering if thats over kill. Thanks!

 

[mcgyvr]

You didn't provide nearly enough detailed information to go on but it could be as simple as any high quality tool steel hardened (RC 60/64) /ground/lapped (52100 alloy?)

Tolerances/temperatures/material (alloy) to be measured,etc..???

 

[NickE]

O1, A2, work well. You want a material that is very abrasion resistant. This normally requires a hardened steel. Alternately I guess you could use an alloy steel and carburize it.

either way 17-4PH is soft and rather expensive for the job.

Nick

 

[DrDroids]

Thanks for the replies! I will be checking the ID of a 6101 aluminum tube with this gauge at 68 deg Fahrenheit. The tolerance on my gauge is +/-.0005.

@NickE, Would I be able to use those materials (01 or A2) without heat treating? My boss wants the gauges as cheap as possible.

Any opinions on 304 stainless steel?

 

[TVP]

Type 304 is a very poor choice, especially for this particular application. It is soft, has poor wear resistance, and will gall easily with Al. The cheapest solution will be to purchase drill rod that is already hardened, and then just grind the OD. Drill rod is typically O1 or similar tool steel.

 

[mighoser]

How about just buying some class ZZ pin gauges? MSC or Mcmaster have them in tool steel for a few dollars each.

 

[dbooker630]

We use Carpenter/Latrobe Graph-Mo (AISI O-6) for many of our gaging needs. It is reported to have better heat treat stability, higher wear resistance, and lower toughness compared to O-1. Check out

http://www.latrobesteel.com/assets/documents/datasheets/Graph_Mo.pdf

for a data sheet.

 

[arunmrao]

The cheapest could be 410 grade . Look for worn or broken tools, and you may be able to grind them and use as your gage. If there are any over size gages in disuse, you may salvage them. I only pray, that you do not end up with ncrs in your tubing, in your search for a cheap tool gage!!

 

[DrDroids]

Thanks for all the helpful info everyone!

 

[NickE]

Heat treat for Oil or Air hardening tool steels is going to be on the order of dollars/hundreds -- independent of the material choice a go/no go at .0005" is going to have to be ground, your largest cost for producing your gauge. What is the basic diameter?

Pre-Hardened drill rod can work, just get it big enough over the basic diameter, OD grind/polish one end to your max, and the other end to the min. Paint a Red stripe, and a green stripe on it. Heat shrink a label at the center handle section.

It really is that simple and that's likely your lowest cost option, anything else is likely more. (Except just buying gauge pins and a handle)




Nick