Making Allen Wrench Sockets

[BigBoy1]

I need to make several Gib bolts that were missing on the lathe I'm rebuilding. The ones that are present have an Allen Wrench socket in the head. I have no access to rotary broaching tools so is there someother method that can be used to make the hexagonal hole in the bolt head? Thanks.

I can always resort to a slotted head but would perfer the Allen socket head.

Bill

[oldtiffie]

Wow,

it must be tough where you live Bill.

I had to go to my steel supplier here in OZ a couple of times this week and included several lots of high-strength "hex" socket screws (metric);
- Hex head socket screws (HHSS): round head with hex socket;
- hex socket in a countersunk screw; and
- plain headless socket screws.

They carry a pretty full range of inch and metric on-hand and if not are only a day or two away on a regular delivery run.

[NickH]

You could use a setup like this to get your hex but with a 1.5 to 3mm corner radius



(This shows an adapter plate clamped to the mill's locked quill which allows outboard mounting of a RotoZip which will run fast enough for 1.5mm carbide endmills, I broke a few until I goth the feel for DOC and feed )

then file or make a broach to sharpen the corners,
Regards,
Nick

[Ian B]

Not sure how the sizes would come out, but can you tap a hole in a gib bolt, and then permanently loctite an Allan grub or cap screw in, to give you the hex socket?

Ian

[BigBoy1]

Originally Posted by oldtiffie

Wow,

it must be tough where you live Bill.

I had to go to my steel supplier here in OZ a couple of times this week and included several lots of high-strength "hex" socket screws (metric);
- Hex head socket screws (HHSS): round head with hex socket;
- hex socket in a countersunk screw; and
- plain headless socket screws.

They carry a pretty full range of inch and metric on-hand and if not are only a day or two away on a regular delivery run.

I looked at manufactured socket Allen head cap screws but the head diameters are too small. The thread is 0.3125" and the diamater of the head must be 0.625".

Bill

[kmccubbin]

How about buying screws with the correct head size, then machine the shank smaller?

Kerry

[oldtiffie]

Thanks Bill.

The requirement is for a 5/16" thread and the head is to be 5/8"OD.

Is it possible to use a standard 5/16" hex head socket screw with a say 5/8" OD x 5/16+"id x say 1/8" (or to suit a slot in the gib) thick washer/disk as a temporary measure at least? The gib/s shouldn't need adjustment too often. The "washer/disc" could secured to the screw head with an adhesive or perhaps be silver-soldered onto the head if needs be.

[SDL]

Originally Posted by BigBoy1

I need to make several Gib bolts that were missing on the lathe I'm rebuilding. The ones that are present have an Allen Wrench socket in the head. I have no access to rotary broaching tools so is there someother method that can be used to make the hexagonal hole in the bolt head? Thanks.
Bill

What material are you making them out of.

Try on a bit of scrap drilling at the AF of the allen key size, cut the angle off a std top quatiy allen key,syareoff to fine finish on grinder, put in tailstock and wind in, We used to make large pan hd allen and torx srews in 304 stainless.

Steve Larner

[A.K. Boomer]

Originally Posted by NickH

then file or make a broach to sharpen the corners,
Regards,
Nick

Your approach is similar to what I use when in a pickle except I just pamper a low RPM after a plunge cut with a max diameter endmill and just take out the corners with the smaller endmill --- I add one thing though,
I dont make a broach to take out the corners - I just rotate the rotary table 30 degree's for a re-start and then install the appropriate sized tiny endmill and readjust the X axis and plunge cut the corners out for clearance --- what you end up with (besides even more time invested ) is a socket head thats not only stronger than standard - it's easier on the drive allen flanks to boot, Its the reverse order of Snap-on's "flank drive" system in which the socket is the drive with the radius corners instead of the fastener ----
Im so limited on RPM's on my mill that I can only do this on fairly larger socket/bolt heads, But its nice to be backed into a corner for not having the equipment and yet end up with a superior Job because of it (despite the extra 20 times the amount of time it took ) Not only that - it just plain looks cool.

[Roy Andrews]

similar to sdl when i need something custom Allen or torx i take the desired bit and chuck it in the lathe. then with my dremmel tool and the smallest grinding burr or diamond burr i hollow out the end to create cutting edges on the points. you have to use a high quality bit if you want it to last and don't over heat it. then chuck up the bolt and drill a hole the same size as across the flats of the Allen. now put your broach in the tail stock and put some good cutting oil on the hole. crank the tail stock in until it stops. back it out and pick out the burs and drive it in again. repeat as necessary. if you have a small lathe or are doing a big hole you may have to use a press. i have even hammered the bit in with good results. with really small allens you can just grind the end flat and then hone it real smooth and they seem to cut well.