Topslide problem

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mikelkie

Well-Known Member
Joined
May 5, 2016
Messages
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Location
Johannesburg South Africa
I often wanted to turn small tapers wit a live centre to support the work, but the tail stock jams the hand wheel of the top slide when set over to the required degree. So using the bevel gears from a Bridgeport quill feed, i made a 90 deg setup witch works surprisingly smooth. All needed to do make new collar with 60 divisions instead of original 120 div. since the ratio of the bevels is 2/1

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Slick.

It is problems like this that have me considering CNC or an electronic leadscrew setup. Being a working stiff i just don't have the time to build either solution.
 
Very innovative solution.

My idea was to make a purpose built, heavy duty tailstock adapter similar to a steady but with some partial relief for the top slide. But it remains in 'digital form' for now :) I have a hunch it might not be as beefy as a stock tailstock. OTOH, I think tailstock mass is about axial loads & accommodating the quill etc. I havnt done a lot of between center taper turning but guessing probably not advisable to take deep cuts. I guess the weakest link is the centers themselves & I would hate to have a piece of work let go under power.

As a side note, I always wondered if it would be feasible to have an (inline) gear reduction add-on that would give finer feed resolution than ~.060 line graduation separation = 0.001" in feed. This would be useful for say tool post grinding (although I still trust an add-on indicator).

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Very nice!! I've never seen that set up before but it sure does solve the problem. I may have to borrow your idea....

Pete

You are most welcome, i saw this setup i think on a Kerry lathe's tail stock
i'm not sure if this idea was extended to top slides by lathes makers. Admittedly its not the best solution but i can now swing the top slide over by 22
deg with the back end just clearing the tail stock which is much more that one
need to turn a taper with the large end towards the chuck. Some scrapped material and 22 hours of thinking & laboring.(i'm a slow worker):(
 
Very innovative solution.

My idea was to make a purpose built, heavy duty tailstock adapter similar to a steady but with some partial relief for the top slide. But it remains in 'digital form' for now :) I have a hunch it might not be as beefy as a stock tailstock. OTOH, I think tailstock mass is about axial loads & accommodating the quill etc. I havnt done a lot of between center taper turning but guessing probably not advisable to take deep cuts. I guess the weakest link is the centers themselves & I would hate to have a piece of work let go under power.

As a side note, I always wondered if it would be feasible to have an (inline) gear reduction add-on that would give finer feed resolution than ~.060 line graduation separation = 0.001" in feed. This would be useful for say tool post grinding (although I still trust an add-on indicator).

My attempt to find a way of turning small tapers is hobby related since the need for
small taper pins is not popular with suppliers To source these would require an order for at least a kilo perhaps a thousand of a size where one only need maybe ten or so
hence my "improvement" on my lathe. On my other lathes i will in good time do the same perhaps making small universal couplers. Just try your idea it will be
worth the effort.
Good luck,
Mike
 
I too have found problems with sourcing taper pins and the cost is silly
My local supplier is $3.50 each small ones under 1/8" but at 2" long
i assume i can get 2 from each.I too thought of making my own from silver steel,but decided for now just to buy a small no for what i need
How do you go about it,what problems do you have etc
The taper is constant so once you get it right you can pin the compound
But do you use tailstock support etc.Thought about setting the taper
on a fixture and grind them on a diamond wheel.Your thoughts would be greatly appreciated
 
While that is a very elegant way to solve that problem. A simpler way is to have a light duty live center like those from Concentric. Spring loaded to cope with expansion, and an Mt-2 to Mt-2 extension will give you all sorts of room.

I like tapered pins, my Ace hardware store has most sizes, limited in lengths, but they tend long, save the cutoffs. Ebay if a qty or special material. Msc for exact needs. It does hurt to pay $1.50 for a single pin, but often that all thats needed.
 
Hi Bazmak and Mach Tom Thank you for encouraging comments.
When i make some t pins i set the top slide over to the required degree using a dti. along the taper reamer.Then turning the stock down to the size needed with the end supported with a small live center. I use a razor sharp hss cutter pointed with tiny radius. Smallest pins are ,8mm at the small end and cut about 10 mm long afterwards. There's no need for hard material for commercial pins are on the soft side, may be EN1A. I did use a tool post grinder @ first but the finish of the hss cutter is acceptable with a sandpaper rub at high speed. The lathe i use is a Weiler Praktikant and i fit a Herbert collet attachment when turning small stuff. I imagine that one could make a fixture for tapered stuff etc. i made some jigs and other fancy tools to make life easier in the shop but after some time i cannot remember what that articles and jigs were for.:mad:. The taper size is expressed in 1/4 in to the foot about .8 deg according to the top slide marking. I must add that i did not make drawings of this but merely pencil sketches of ideas and failures of course, but i will soon load up more pics when i strip it down to make the graduated collar (if i cannot buy one) The biggest problem i had with such tiny turning is the flexing away, but very light cuts and very sharp tool takes care of that
after a couple of passes
Regards Cheers
Mike
PS i don't have wheels to slow me down, i just drag my feet along;)
 
Slick.

It is problems like this that have me considering CNC or an electronic leadscrew setup. Being a working stiff i just don't have the time to build either solution.

Busy people don't have time, so one has to make time do something that you will enjoy making and using or playing with. My lawn was in desperate need of mowing at the time but i made something useful. I did the lawn a week later:p
 

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