Tapered drill for a tapered pin?

I'm a newbie trying to re-purpose a handwheel to put on a G&L radial drill. The handwheel slides on the shaft and is held in place by a tapered pin. The pin is .201 on one end and .221 on the other and is 1-1/4" long. Now I need to drill the new handwheel for the tapered pin. Do I buy a tapered drill for this? Thank you for your help.

As there's only 0.020'' of taper to come out, I'd uses just a taper pin reamer, …….FWIW I'd drill 5mm or #9

You need to go back and measure your pin. Standard taper pins have 1/4" taper per foot. If I do the math on yours, it come out 0.192". A #3 pin has a large diameter of 0.219". A #4 pin is 0.250 at the big end. All per Machinery's Handbook.

I'm guessing it's supposed to be a #4. You'll need a #4 TP reamer, about $20.
I hope that you have an accurate way to locate the new hole in the handwheel.
JR

Seems a lot of taper pins on older machines were hand drilled, you may have a problem with alignment drilling the hand wheel.
I think i’ed go with a split/spring pin in a diferant location.

So, it looks closest to a #3 pin in the book. Do I drill it to the small size and then get a #3 tapered reamer? It sounds good. I didn't see a recommended drill size in the Machinery's Handbook. Thank you.

If drilling it by hand, you can assemble it with a shim washer between the hand-wheel and the casting, drill/ream the hole, then remove the shim. Otherwise you risk it binding when assembled.

It's unlikely you will get the hole drilled and reamed with a full clean up with out needing a larger pin. As others said they may have drilled and reamed the original by hand so it depends on how much time you spend and the amount of work you're willing to go through. I like to have 100 percent contact for the new pin, not important for a lot of applications but if it's going to be rough handled or power feed then it might be.
Dan

I bought a set of tapered drill bits for installing taper pins some decades ago. They may be hard to find these days.

The usual method is to drill a straight hole the size of the small end of the reamer clear through the hub and shaft, and then ream with either a straight flute hand reamer or spiral flute machine reamer. It is unlikely you can drill just the hub so that your hole lines up perfectly with the old hole in the shaft, so you might as well drill a new hole in the hub and a different part of the shaft.

It is usual to stock long tapered pins and cut off one or both ends to suit when fitting a new pin.

Larry

Measure the small end of the pin and compare it to the nearest size drill bit. Should be able to get a number drill that is close to the right size or a few thousandths smaller. Get you a sprial cut tapered reamer for the size needed and use it in a cordless drill or air drill. Use lots of cutting fluid to ream the hole out until the pin is about 1/8-3/16" from not protruding out the bottom of the freshly reamed hole. Blow out the hole, insert pin and drive it in tight using a 5/16" Starrett pin punch. Once driven in, it should be very close to flush on the small end. That portion that is sticking up on the big end, either leave as is or file flush with OD.

Ken

Sounds like I'm getting into more than I thought I was. But I want to try it. That's the best way I know how to learn. I will try all your advise. And thank you.

On small taper pins were it's hard to differentiate between the head and tail ends we used stamp the hand wheel head end with small letter stamps. It'd look like H-O-D were O is the pin head.

I had some taper drills in my box but I rarely used them. I just drilled the same size as the reamer bottom and used the taper reamer in an electric drill with speed control. Run the drill quite slowly with some cutting fluid.

Regards Tyrone.

Tyrone Shoelaces said:

On small taper pins were it's hard to differentiate between the head and tail ends we used stamp the hand wheel head end with small letter stamps. It'd look like H-O-D were O is the pin head.

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That's considerate! Sure wudda been nice to have followed you, years later and had less risky mystery than usual



"Company" stamps were a go-fetch item, long walk.

I've used the tip of a narrow Cape chisel to create a "sort of" "+" next to the large end and a "-" next to the small end.

Better than nuthin'

thermite said:

That's considerate! Sure wudda been nice to have followed you, years later and had less risky mystery than usual



"Company" stamps were a go-fetch item, long walk.

I've used the tip of a narrow Cape chisel to create a "sort of" "+" next to the large end and a "-" next to the small end.

Better than nuthin'

Click to expand...

I had a set of 1/8" letter and number stamps. It took about 5 secs to do and saved you ages. I've known fools file and emery the head and tail over. Now find that pin after about 5 years wear and tear.
If you look very, very carefully after polishing the area with wet and dry paper you can just about make out the difference in grain colour.

Regards Tyrone.

Tyrone Shoelaces said:

I've known fools file and emery the head and tail over. Now find that pin after about 5 years wear and tear.


Regards Tyrone.

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That is a dick move!
Joe

Joe Rogers said:

That is a dick move!
Joe

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I know but people do it thinking it looks neat. Until they need to remove the pin that is !

Regards Tyrone.

Tyrone Shoelaces said:

I had a set of 1/8" letter and number stamps. It took about 5 secs to do and saved you ages. I've known fools file and emery the head and tail over. Now find that pin after about 5 years wear and tear.
If you look very, very carefully after polishing the area with wet and dry paper you can just about make out the difference in grain colour.

Regards Tyrone.

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Arrgh. Five DAYS, even.

I've been know to do the reverse, "now and then" when I thot it might matter. Not only be pleased to have put a nice round crown on the small end, but touch the large end with a c-drill tip to put a divot into it.

Small end then can be started back out with a punch similar to a carpenter's "nail set", and sometimes a "nail set" is exactly wot I have used. Anything that cups onto the projection to guide itself so it needn't even mar the paint.

Now to ME that divot at t'other end is a subliminal reminder that sez "don't punch HERE, you'll upset it like a rivet and jam it, fool!".

Modern kids, of course, never made nor even used store-bought rivets, let alone flush-head "blind" riveted a fixture together, "just TiG it" for everything instead so...

Mind, humakind didn't start out brilliant. Just re-reading the Engineering (or so they called themselves..) post-mortem on the Tay bridge collapse last night.

The marvel of some of those old structures (Firth of Forth bridge being a shining GOOD example) is not how well we did it, but that we managed to do it AT ALL with what they had to work with - human resources easily as badly constrained as metallic ones.

Of course there is the alternative I came across recently


Mark

old-biker-uk said:

Of course there is the alternative I came across recently
View attachment 235412

Mark

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LOL! Too late, mate... we've seen that Movie before!

G'Dad, Day Job B&O "Roundhouse" foreman, was BFBI crude on his farm and orchard equipment repairs.

He'd ha' done that with a soft-iron rivet and figured his solution "elegant" by comparison 'coz he stocked plenty of sizes of them and hadn't used an ignorant nail.

To be fair, soft Iron rivets tend to fit-up tight and can be taken out easier than more than a few buggered taper-pins I've met. Maybe he wasn't so ignorant, after all?

A lot of stuff I work on due to shaft sizes it is important to pick up the original hole and not oversize if possible.Best way is to drill the new part on center with the hole same size as the small end of the shaft on one side only,slip part on and drill the other side using the shaft as a guide( this will also help if the hole is not on center).

Then use the taper reamer to finish to size.I have a bunch of scrap short round stock that I have drilled and reamed to serve as chucks to machine the new pins to size and champher the ends(important to tell the large and small ends apart when installed and to remove without mushrooming the ends).Install in the part and mark where to cut,remove, tap the new pin in the scrap chuck and machine in the lathe,cut the sm end short and large end long.

The new pin should protrude slightly so that a heavy hammer blow will pop them out.

The Jagenberg machines we have are the only machines that I have worked on that have every tp hole on center,a relief to work on!The 4-5 million dollar KBA presses are hand drilled all over.

This reminded me of one unpleasant tp job.We had a press that used tp's to hold all the oscillator rolls in place(28 rolls pressed onto 60mm 10ft shafts that had to be pressed on in place) and were assembled with one 10mm pin in one end only.After awhile they would work loose in the roller collars,never in the shafts,So they had to be drilled out in the machine.a pain in the ass.Ea print unit used 4 rolls, so we had 4 spares made up with 2 12mm pins,one in ea end to cure the prob,whenever downtime available we would swap out.

One unit needed repair and could only be down Saturday so as to start up Sunday.New supervisor asked if I would do it as every body capable was unavailable.Its a 2 man job but since he was a good guy I agreed.Mistake #1.

He asked if there was any thing 2ed shift guy could do to help.The new pins had not been drilled and fitted to the shafts and rollers so I said if he could take care of that that would save a couple hours.For a moment I thought how could this asshole screw this up(mistake #2}.He had helped me do this before so I figured no way.

Saturday at 7 am I found out how.He deliberately hammered the pins in and filed/sanded the pin ends so as to not know which ends were which(after the pins are fitted they have to be removed & marked so they can be installed in place).I should have called the super in told him to handle it(Mistake #3)Deilberate sabatoge would probably got him fired.

Tried every thing to find the ends,heating to color will sometimes revel the hole line.Acid might have worked.Ended up spot drilling around the area and managed to get them out. Finished the job 12 hrs later.

In my youth 2ed shift guy would have walked into a knucle sandwitch Monday.