JARNO #18 taper

I'm looking for a #18 Jarno taper dead center.
Does anyone have one to sell?
Thanks.

No, but I genuinely feel bad for guys that have equipment with unusual (and attendantly expensive) tapers. I wish you luck in your search.

Head stock taper in my twenties Greaves Klusman 20" Heavy engine lathe. I'll be grinding up a sleeve (down to MT5) from a MT6 / MT5 sleeve

Yeah, I'm thinking an adapter sleeve might by the OP's financially best course of action. Future proof the situation.

I agree the adapter route is one way to go.
Found this on eBay, it could be machined to fit. http://www.ebay.com/itm/USED-GORHAM-20-JARNO-LATHE-DEAD-CENTER-
It's 0.25 large on the big end and 0.125 on the small end. Probably could turn it in my lathe but I would still like to grind it after to assure a proper fit. All that would cost me a lot more than buying a new one from Stark Industrial for about $230. Maybe I'll have to bite the bullet and come up with the $230.

A few years ago I worked on a " Churchill " cylindrical grinder that had that taper. We could still get centres in the UK, both plain and carbide tipped. I can't recall where from now though.

Regards Tyrone.

try Riten. Jarno is still in common use on many cylindrical grinders..... you just don't see them as much as the morse. I personally like the jarno system better, all the same tpf, just size and length changes....

Hello Wille06709
I found one at Stark Industries about $230.
Thanks for your comment.
I like the Jarno also it makes sense compared to all of the other systems.

Having looked at ebay and not found a Jarno #6 live center. I elected to make a couple adapters.
Strange as it is my not functional at the moment lathe's taper attachment is set for a 6 deg Jarno taper.

I dont have any material that size of known parentage big enough for a #18 so I cant offer to turn one when things are repaired.

So Ill just say it isnt all that hard to make.

The taper could be turned on the lathe but it's hard to grind the taper to a close tolerance afterwards.

roadcracks said:

I agree the adapter route is one way to go.
Found this on eBay, it could be machined to fit. http://www.ebay.com/itm/USED-GORHAM-20-JARNO-LATHE-DEAD-CENTER-
It's 0.25 large on the big end and 0.125 on the small end. Probably could turn it in my lathe but I would still like to grind it after to assure a proper fit. All that would cost me a lot more than buying a new one from Stark Industrial for about $230. Maybe I'll have to bite the bullet and come up with the $230.

Click to expand...

I have lathe turned and crocus cloth finished centers for as good as grinding. A blue up and fit is very good. For point a hand turn in an oiled V block under a SG angle dressed wheel make a dead true center.

You can check the existing point and if true set that into a lathe chuck held tool bit cut hole in a slug to hold head end with a solder or brazed driver tab.. the back on tail center and turn as true as your lathe.. with the few tenths error crocus clothe finish to blue fit..or a plate check angle and a blue up.
I used to check them (points)rolling in a V block with a small ball in the back center against a stop..

The tool bit cut hole will be dead true to spindle, much better than a drill or center drill hole.

Mostly I ground centers (taper and points) on the 13 grinder looking for .00005 or less error. yes no show on a tenth indicator.
One tenth off center and the part is two tenth off..

roadcracks said:

Hello Wille06709
I found one at Stark Industries about $230.
Thanks for your comment.
I like the Jarno also it makes sense compared to all of the other systems.

Click to expand...

Riten's specs are arguably a tad finer, but I bought my 10EE's #12 Jarno goods from Stark, saved a few bucks, IIRC, and am well pleased with the quality.

Bill

Am I wrong in thinking that with the Jarno system of tapers where all the taper per inch and angle from center are the same regardless of size, a lager size will fit in a smaller female taper but just wont go in as far?

pomsct said:

Am I wrong in thinking that with the Jarno system of tapers where all the taper per inch and angle from center are the same regardless of size, a lager size will fit in a smaller female taper but just wont go in as far?

Click to expand...

By definition, Jarno is .600" taper per foot on diameter, regardless of size

The 1/8" difference between an 18 and a 17 (if there was such a thing) would mean an axial mismatch of 2.500" - because .600" taper per foot on diameter is also .050" taper per inch on diameter - and .125 divided by .050 = 2.500

johnoder said:

By definition, Jarno is .600" taper per foot on diameter, regardless of size

The 1/8" difference between an 18 and a 17 (if there was such a thing) would mean an axial mismatch of 2.500" - because .600" taper per foot on diameter is also .050" taper per inch on diameter - and .125 divided by .050 = 2.500

Click to expand...

Confirming that the lazy man's way... the 10EE spindle didn't actually expect to use a full #12 Jarno, but rather a slug with integral, smaller DC ELSE one that adapted to smaller MT.

The #12 hangs out far enough to grab scarce daylight on a mere 20" c-to-c lathe, so I picked up a #11 Jarno DC expecting merely less-intrusive hang-out.

"Curses, foiled again!

Hadn't given a thought to Monarch only having used the 'middle' of the #12 jarno.

It slid clear down the bore!

Monarchist said:

Confirming that the lazy man's way... the 10EE spindle didn't actually expect to use a full #12 Jarno, but rather a slug with integral, smaller DC ELSE one that adapted to smaller MT.

The #12 hangs out far enough to grab scarce daylight on a mere 20" c-to-c lathe, so I picked up a #11 Jarno DC expecting merely less-intrusive hang-out.

"Curses, foiled again!

Hadn't given a thought to Monarch only having used the 'middle' of the #12 jarno.

It slid clear down the bore!

Click to expand...

So if i'm understanding this correct, you can put an oversize Jarno taper in a smaller female Jarno so long as the small end of the male taper will fit into the large end of the female taper. I have a 15X48 Clausing with a L1 spindle nose, It appears to have a #18 Jarno taper on the inside that is about 2 1/2 long. Originally the lathe had a spindle nose bushing that reduced to a #3 morse taper but is missing and doesn't seem to be readily available anywhere. There doesn't seem to be a lot of Jarno taper tooling available anywhere. I can find some larger Jarno taper centers that's why i'm asking before buying something that won't fit. The #18 Jarno taper has a large end of 2.25, The #20 Jarno has a large end of 2.50 and a small end of 2.00. Shouldn't it slide in with 5 inches hanging out the front?

pomsct said:

So if i'm understanding this correct, you can put an oversize Jarno taper in a smaller female Jarno so long as the small end of the male taper will fit into the large end of the female taper. I have a 15X48 Clausing with a L1 spindle nose, It appears to have a #18 Jarno taper on the inside that is about 2 1/2 long. Originally the lathe had a spindle nose bushing that reduced to a #3 morse taper but is missing and doesn't seem to be readily available anywhere. There doesn't seem to be a lot of Jarno taper tooling available anywhere. I can find some larger Jarno taper centers that's why i'm asking before buying something that won't fit. The #18 Jarno taper has a large end of 2.25, The #20 Jarno has a large end of 2.50 and a small end of 2.00. Shouldn't it slide in with 5 inches hanging out the front?

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I've just tooled-up an Alzmetall AB5/S with a whole passel of 5 MT downward adapters and sleeves the fewer steps and stacking errors, the better. Even so, I don't see where you are going with this applied to Jarno.

It had merit. Still does. B&S supported it - Oscar Beale was 'their man' after all. He wrote articles for scholarly works and trade rags alike, gave presentations at symposiums and exhibitions, and in general spent many years of his life proselytizing the jarno taper.

It COULD HAVE replaced both MT and B&S tapers for a saner world. Look, however, at its timeline. That opportunity for 'universality' had largely passed by the time the USA swung into production for the First World War. The older two tapers were just too deeply embedded in drills (B&S taper existed as well as MT) and milling-cutter holders to overcome.

You just won't find many instances where a Jarno has to be stacked even ONCE. Too rare.

Conceptually, you are 'good'. That was part of Oscar's goal. BOTH B&S and MT have anomalies in their range, do NOT insure the same taper, all sizes.

Jarno does NOT change.

What you postulate is still not assured in instances where only a part of the taper was used. "Jarno-Reed" was one such. Angle is the same, gage line is not only offset, but not everyone who did that even used the SAME partial section.

Dunno if they still have any of it left, but Grand Tool in PA had NOS/stale shelf stock in the #12 Jarno - plus that #11 test one - a firm in PA was making those ages ago.

For new jarno goods, see Stark or Riten, else set up for it and DIY.

Far too late and wrong century twice-over to bring jarno back to life other than for what is in your own hands.

Think NMTB/CAT/BT/DeVlieg/Ericsson, R8, HSK and Capto. See also seriously good grip for straight shanks from ER, TG, DA, Ortlieb, and others.

And we NEED those serious-grip 'collet' chucks.

Solid-carbides are not common on any form of taper shank, inserted perhaps only on MT.

No much food left on the table for the 'alternative' legacy tapers, nor even Morse.

Check with these folks for a 5C collet adapter:

https://www.jfkprecisionproducts.com/

Then there will be a vast supply of things to fit the spindle with adapter in place.

I have a 15X48 Clausing with a L1 spindle nose, It appears to have a #18 Jarno taper on the inside that is about 2 1/2 long.

Click to expand...

If one takes a look in B5.9 Spindle Noses they will see L1 had either MT5 or American Standard 200. L2 has Am Std 250 - both are .750 taper per foot on dia.

Fair chance Clausing - wanting bigger - cobbled up their version of the non existent Am Std 225

Fairly easy to confirm by measuring. If taper is nearer .750 per foot on dia. than it is .600 taper per foot on dia., it IS NOT Jarno

johnoder said:

If one takes a look in B5.9 Spindle Noses they will see L1 had either MT5 or American Standard 200. L2 has Am Std 250 - both are .750 taper per foot on dia.

Fair chance Clausing - wanting bigger - cobbled up their version of the non existent Am Std 225

Fairly easy to confirm by measuring. If taper is nearer .750 per foot on dia. than it is .600 taper per foot on dia., it IS NOT Jarno

Click to expand...

I measured the taper with an indicator and it is .031 per inch not .025 per inch as I suspected, so I'm sure you're correct about this spindle nose internal taper being a 200 or 250 American Standard. I think everybody measures the large end at 2.250 and go for the Jarno because is's the only one that has a 2 1/4 large end measurement. It's easier to assume than it is to actually measure it. OK now where do I find a spindle nose bushing for this machine?