No idea. Looks to be pretty much standard 29 degree. But Ill have to put it on a comparator and check
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."
- Proverbs 22:3
Brinks from the looks of it.
That bronze sleeve would work well. And I could saw it in half and make a spare.
Thanks for the link
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."
- Proverbs 22:3
No..unfortunately. No way to halve the gearing below 11
Damnit
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."
- Proverbs 22:3
According to Gunner :
[ ... ]
Don't you have a Clausing in your collection? My Clausing (a
5418) includes 5 TPI in its quick-change box.Good Luck, DoN.
No, no, no, nooo, dude!
The largest thread it will do without having to muck with gears is 11. :-)
(I'll hedge that by saying that other than drooling on the odd one, I do not have a pile of intimate experience with a HLV-H.)
Got gears between the spindle and the gearbox, or are they fixed and immovable?
Set the box to cut 15, and swap gears in to triple the speed of the input side of the box, and you're there. Run really slow spindle rpm.
Upping the tooth count on the spindle gear is the most effective way to do this, on most of the lathes I have seen.
Gotta have some gears around, though, which can be a kicker.
Lotsa good reading about gears and gear trains here. While the specific answer is not given, think the information is there for you to work out a solution, but it will depend on what gears you have on hand.
Just remember that in the end you need a 5:8 ratio from your spindle to your leadscrew. (I think I got that right, five turns of the spindle equal to 8 turns of the leadscrew, same as 5 tpi) or it's equivalent including the gearing in the box.
If I understand the info from the links below, there is at least one position in the selectors that allows a 1:1 input output ratio through the gearbox.
Then it's a matter of finding the gears to fit the ratio you need on the banjo.
Cheers Trevor Jones
What gear runs on the spindle-----20 tooth? Replace it with a 40 tooth. Regardless of what they tell you, unless the spacing doesn't permit the exaggerated ratio, if you double the speed going in the quick change, you'll achieve your objective. You need work only with two gears, the one from the spindle, and the one that drives the quick change. Determine the existing ratio, and double it. Count teeth if necessary. It's pretty straight forward, assuming you have the gears. I've done it on a few occasions with my Graziano------plus I've run it with the feeds cut in half almost as long as I've had it. I had an 80 pitch thread to cut in tungsten balance weights for gyroscopes in guidance systems. Couldn't dial the 80 pitch directly, so I cut the speed in half and set the lathe for 40 pitch threads, which yielded the 80 pitch thread. Liked it so well I've left the setup-----and it's been years------since about '69, -----although I occasionally make a strange setup for cutting a coarse thread. When finished, I always return to the half feed rate. Works well for making small parts, which was my specialty.
Harold
Ive got two full sets of auxillary change gears. No joy.
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."
- Proverbs 22:3
You are aware of the unique way Hardinge links their threading lead screw to to the carraige? In a threading operation..one NEVER opens the half nuts. The carriage is powered backwards and forwards with the half nuts kept closed. No threading dial on the machine needed.
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."
- Proverbs 22:3
Our Clausing/Metosaa do also. I just turned hal a doz. 3/4 x 5 Acmes for new push broom handles to replace those crummy cast "thingies" that come with them. :-) ...lew...
I was not aware, but that does make it easier, as one need not worry about getting out of phase with the leadscrew.
One of my work machines has a ballscrew rather than a leadscrew for thread cutting. Was a bit of a job getting the hands to not reach for a half nut lever.
Cheers Trevor Jones
Yer gettin' altogether too focused on whats in the manual Gunner! :-)
Understand how it works, rather than understanding how to read the manual.
Key is to understand that, as your lathe sits, if you gear the spindle to the leadscrew directly, at a 1:1 ratio, it will cut a 8 tpi thread.
All the gearbox does is allow you to select from an assortment of ratios without having to swap off gears.
Pick the right ratio from the gearbox, drive it at the right ratio from the spindle, and you can cut any thread.
:-)
Cheers Trevor Jones
Chuckle..true enough. Though..give the nature of Hardinge documentation and their machines..Im fairly confident that if it were possible to do a thread larger than 10 tpi..it would have been included in the chart.
You have to be around Hardinge machines and their documentation for a while..to understand what Im talking about. Im sure other Hardinge owners here know this as well.
Gunner
"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."
- Proverbs 22:3
Well, the fellow that posted to one of the threads I linked off the practical machinist site, seemed to beleive it was possible.
Too bad I am so far away! I'd enjoy seeing your pile-O-stuff. Can't afford the cats though. :-)
I figure if a guy can make a bitty little Myford cut 1 TPI, anything can be done. It pretty much boils down to motivation.
If I read the charts right, set up A, look at the gears for 10TPI, and double the first gear to a 44 tooth.
If I am reading the chart right, in conjunction with the picture here
Cheers Trevor Jones
see
Unka' George (George McDuffee) .............................. Only in Britain could it be thought a defect to be "too clever by half." The probability is that too many people are too stupid by three-quarters.
John Major (b. 1943), British Conservative politician, prime minister. Quoted in: Observer (London, 7 July 1991).
I use mogolice on way repair but would not use it on a nut since nurs are easy to make and I can't have a new nut fail on a customers machine.
Inserts are easy to come by if you look. You dont necessarily have to have the proper insert for the pitch. If you have a smaller one you can shift the compound and enlarge the width of the thread to match the pitch. I would recommend handgrinding some tool steel and use an unworn section of the screw for a gauge... Make sure you have enough clearance for the helix angle. I may even have some acme taps for that pitch nut. Just finished doing some wierd pitch (.395) double lead stuff. Custom propriatory threads. ( thats not really the correct pitch. its proproatory :) but you get the idea.) Top notch type inserts would be what I use for most acme threads. Get yourself an acme pitch gauge and it makes hand grinding a hss tool easy. Just remember the helix relief.
John
To simplify everything all gunner has to do is to make the first gear in the diagram turn the same rate as the screw gear. If you look at the gear setup A you can see the 10 tpi is exactly half ratio, so if you just put an idler gear between the screw gear and the first gear and that will give you 5tpi.
John
The one point to make is that the gear train may not be able to take the load for the lower pitch settings and that is why they don't have them in the manual. If you try it, run it slow.
John
The quick change on a HLVH is not driven by the external change gears. If you're using the external gears the quick change is disengaged, and when using the quick change any external gears must be removed or unmeshed.
Ned Simmons
Thanks, Ned. Clearly shows my lack of experience with the "large" Hardinge lathes. While I've seen them, I've never operated one.
Harold
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