Tapping Threads - Object Orientation

[freebo86]

So this may be a stupid question, but when I tap a new hole & thread for something to screw into. How do I get the thread to be done in such a way so that when I take the object or whatever I may be screwing into the newly finished tap so that the object will point in the direction I want to point it?

In other words. I have a bracket, that I am screwing a 90deg grease fitting into that I need the fitting to point to the right of said bracket. Now when I screw it in, its pointing, down, left, halfway between down/up.. its like trial and error.

Is there a specific way to tap the threads to achieve the end result or a specific way I need to orient the zerk when I start threading it in for it to be pointed in the right direction?

Thanks,

 

[ItsNemo]

As far as I know, it's not possible. You can't easily control where the tap bites in. I would think there's some amount of tolerance though in how tight you need to make the fitting and/or a bit of thread locker or something could help it stay where you need. Failing that, a bit of a spacer like a washer could help orientation.

I guess the other thing is, why does it need to be a 90 degree? Could you put a straight one and then just a 90 degree grease coupler?

 

[gsuty17]

It depends on the threads of your grease fitting. If it is a tapered pipe thread, npt, you can just tap it a little deeper and change the orientation of the object you are threading in. Chances are if it was npt you could just go a little tighter and you'd have been there though. ItsNemo nailed it; if it's not an npt thread they make washers designed for just this purpose. Search for 'crush washers'. The absolute last option that may be useful, if you have room, would be to install a bulkhead fitting in your bracket. You could index that however you wanted it.

 

[WoodsTruck]

It might be like indexing spark plugs. All 90° grease fittings may not be threaded the same either. Get a handful and try them to see if they give you different results.

 

[laser3kw]

try grinding (on the zerk for example) the "lead" taper part of the thread back to "clock" the start point. It takes a couple of tries, but is doable.
for example: if it finishes pointing to 9 o'clock and you need it at 3 o'clock, you would grind the start of the thread start taper back 180°. Or you can do it by grinding the bottom of the zerk (flat) a little at a time to achieve a new start of the thread to end up where you need. I have done both, the second is easier where the part allows it.
I have done the inverse by flat spot facing the female part. But as pointed out, if the male part is replacable, it may not repeat unless you select fit parts - or modify the male part as described.

 

[rsanter]

The issue is the fasteners and the grease zerks are not indexed so to me it really does not matter.
If this is a must have then you need to tap a hole and then put the specific zerk in, then see where it lands. Then you need to reference where the threads starts and start the thread in that location n the actual piece

 

[larry_g]

If you know the thread pitch and the screws into a shoulder then you can do the math and figure out a shim or a counterbore to set the angle Lets assume that the thread pitch is 20 tpi. Each turn of the screw will advance the screw .050", 1/20. So each quarter turn is .0125". So if you want to stop it 90 deg sooner use a .0125 Shim washer.

 

[slowtwitch73]

It's like orienting the screws on electrical outlets/switches... turn it until it's where you want it.

 

[PCustoms]

It's like orienting the screws on electrical outlets/switches... turn it until it's where you want it.

If it's loose use a wrap or two of Teflon tape.

 

[The Cobbler]

the threads , whether tapered or running should be snug enough that you can set the zerk where you want & it will stay there
if not a slight deform in the thread of the zerk will tighten it up enough . it does not have to be air tight

 

[ez-duzit]

...I have a bracket, that I am screwing a 90deg grease fitting into that I need the fitting to point to the right of said bracket...

It is a poor design that requires such precision in a Zerk fitting.

 

[rustyzman]

You can control the orientation of the threads if you thread mill them both on a machine. Then you have control of the entry and exit points of both threads. Alternatively, as others have said, if it is a straight thread and a shoulder is involved, you can control orientation by changing the thickness of a washer under the flange of the head.

Taper thread zerks will allow a lot of "pushing a little further" to align them if needed. They are quite malleable.

Otherwise, thread alignment it is a crapshoot.