Cutting FGHT

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bug_hunter

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Can anyone out there school me on cutting a 3/4-inch FGHT (Female Garden Hose Thread) on my SN9c? I would like to cut it in a 3/4-inch thick piece of aluminum.

Thanks,

Greg
 
Looks like 11.5 tpi. Do you have change gears to cut that thread?
 
DavidR8 said:
Looks like 11.5 tpi. Do you have change gears to cut that thread?
Click to expand...
I have a complete set, so presubably I do. Any ideas what diameter I should bore the hole to? If not easily accessible, I'll just estimate it based in the minor diameter of a garden hose. Thanks a bunch,

Greg
 
There actually is an ANSI specification for garden hose threads but it will cost you $39 to download it from their online store. It would be nice to know what the thread profile is but paying 39 bucks for the info is a bummer. Your requirement may not be all that demanding.
 
This should get you in the ballpark, at least for something like a garden hose. If the thread is 11.5 TPI, then take the OD( major diameter of thread ) and subtract 1/11.5 from it, to give you the minor diameter/tap drill size. Not perfect, but close enough for government work.

Using a 3/8-16 as an example. .375"( major dia ) - .0625"( 1/16 ) = .3125" ( or 5/16", which is the tap drill for 3/8-16 )
 
Definitely not a critical item. I'll give that a shot. Definitely not worth a $39 investment for a sprinkler repair.

Thanks a lot guy. I'll give it a try tomorrow and report back.

Hope everyone has a great evening!
 
I checked the minor diameter of two brass female fittings and they were ,968" and 1.000". The thread appears to be a standard 60º profile.

Garden hose fittings can be fairly loose as the only requirement is that they capture enough of the mating thread to tighten against the sealing gasket.
 
My lathe wont cut 11.5 tpi so for the hell of it I cut 11 tpi, it works just needed a thicker gasket
 
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