Grub screws
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Grub screws
Hi All, looking for an easy way to install a Lovejoy coupling on to a shaft with minimal tools , I am thinking of drilling a small hole into the shaft so that when I install a Grub screw into the coupling it would have a better grip.
Any thoughts?
Geo
Any thoughts?
Geo
If it ain’t broken keep working on it until it is .
Geo
Geo
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Re: Grub screws
A keyway is a far better bet. If you have only light loads, might get away with your plan, but not recommended. You do not mention shaft size. For a small shafts, a through pin is acceptable, for larger shafts, definitely a keyway.
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Re: Grub screws
Hi, shaft is probably 1/2” to 5/8” , not much load just an alternato
r, see pic.sorry I can’t seem to turn the pic around.If it ain’t broken keep working on it until it is .
Geo
Geo
- liveaboard
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Re: Grub screws
That looks like a beefy alternator; 80A or more?
The torque is surprisingly high on that type of thing. I used to burn up V belts until I went to dual belts.
I I suspect a grub screw will fail.
A trick for people without the means to cut keyway grooves; Drill a hole along the shaft and hub, basically creating a round keyhole.
Tap it.
Then you can put your grub screw in, but the entire length with be on shear.
I usually drill a larger hole to countersink an Allen screw head. I use a drill smaller than the screw head, then cut the screw head down on the lathe for a snug fit.
For really high torque, I've used 4 screws.
This hub swings the boom of my hedgecutter, it's turned with a 10 ton hydraulic ram on a lever.
The screws are 14mm (9.16")
The torque is surprisingly high on that type of thing. I used to burn up V belts until I went to dual belts.
I I suspect a grub screw will fail.
A trick for people without the means to cut keyway grooves; Drill a hole along the shaft and hub, basically creating a round keyhole.
Tap it.
Then you can put your grub screw in, but the entire length with be on shear.
I usually drill a larger hole to countersink an Allen screw head. I use a drill smaller than the screw head, then cut the screw head down on the lathe for a snug fit.
For really high torque, I've used 4 screws.
This hub swings the boom of my hedgecutter, it's turned with a 10 ton hydraulic ram on a lever.
The screws are 14mm (9.16")
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- Location: Concord ,NH / Naples, Fl
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Re: Grub screws
liveaboard writes:
A trick for people without the means to cut keyway grooves; Drill a hole along the shaft and hub,
basically creating a round keyhole. Tap it. Then you can put your grub screw in, but the entire
length with be on shear.
This is referred to as a "Dutchman" for some obscure reason. I've used it successfully.
A trick for people without the means to cut keyway grooves; Drill a hole along the shaft and hub,
basically creating a round keyhole. Tap it. Then you can put your grub screw in, but the entire
length with be on shear.
This is referred to as a "Dutchman" for some obscure reason. I've used it successfully.
- liveaboard
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Re: Grub screws
Funny;
I was taught it by a Dutchman.
Old cranky machinist had a shop across the canal from my place.
I was taught it by a Dutchman.
Old cranky machinist had a shop across the canal from my place.
- Bill Shields
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Re: Grub screws
14mm = 9.16"
We all know what you mean but this falls in with Harold's KG conversion.
Gotta love spell chuckers and inductive keyboards
We all know what you mean but this falls in with Harold's KG conversion.
Gotta love spell chuckers and inductive keyboards
Too many things going on to bother listing them.
Re: Grub screws
Commonly referred to as a Dutch Key.
I am from Dutch heritage but have no idea how the name came about.
I am from Dutch heritage but have no idea how the name came about.
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Re: Grub screws
it's been called a "Dutchman" in machine shops for well over 100 years .
Maybe it comes from "Plugging the Dike ?
Rich
Maybe it comes from "Plugging the Dike ?
Rich
Re: Grub screws
80 Amps at 14 VDC is 1120 Watts is about 1.5 HP, substantial load for a set screw or grub screw with a sinosoidal load.
Re: Grub screws
There are keyless style couplings that are a better choice here than the keyed coupling you bought when you have no keyway…..
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3/4" Kozo A3. Delayed construction project
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