GhT geared and retracting top slide

[Bjorn_B]

Got this delivered the other day...

20160609_174553 by Bjorn Bursell, on Flickr

Need to think about that leadscrew, can't live with a imperial one as the other slides on this lathe is metric. Divisions on the existing top slide are strange too, (2mm pitch with 40 divisions...) I don't think I ever have used the top slide for diametric work.

Cheers!

[Bjorn_B]

So a new 2mm left hand pitch leadscrew was made instead (or rather a 1,999mm pitch). Thanks to Grahams excelent screwthreading clutch, this was "done in a jiffy". Oh, bronze chips are form making a new set of input gears for said clutch, lost a tooth on one of the tufnol gears due to over enthusiasm. Bronze input gears from here on...

20160612_140146 by Bjorn Bursell, on Flickr

Finished result, the thread looks a bit thin for a true acme form, but I have other plans so not to worry..
20160612_141123 by Bjorn Bursell, on Flickr

Will make a try for a Acetal leadscrew nut (Evan method), this is the first test, no backlash at all and reasonable free running...
20160612_181525 by Bjorn Bursell, on Flickr

[Admiral_dk]

Hi Bjorn

Thank you very much for this little titbit about the nut.

Per

[Bjorn_B]

*****Updated*****

Been slow here for some time, for reasons I won't bore you with...

Anyways, a session at the mill today, made a start on the body, will do the outline machining later..

20160626_162305 by Bjorn Bursell, on Flickr

All work was on the mill with drills, boring head and reamers, I have a self feed quill on this, very useful..

Also made the sleeve (Added pictures now), but different method to what GHT mentions in his book (a laborous job that also calls for a mandrel to be made up....) made it fit into the bore of the body first, then transfered to a dividing head to mill flats (115 degree spread) and then back to the myford to drill, bore and ream the centre hole after indicating the outer surface in the four yaw. After parting of it is job done... The method GhT mentions in the book is more tedious.

20160627_153350 by Bjorn Bursell, on Flickr

20160627_153428 by Bjorn Bursell, on Flickr

[Chipswitheverything]

Hi Bjorn, you have a very interesting project underway.  Was the acetal feed nut made by a process of heating and squeezing the plastic blank around the finished Acme thread?  I've read about it on other forums, but not tried it.

Yours, Dave

[Bjorn_B]

Dave, it is heatformed. A split, hollowed out piece of POM, is clamped in the vice, heat applied to the leadscrew (carefully). Outer surface machined afterwards

[Bjorn_B]

Been at this for little wile again, still mulling over the leadscrew.. in the meantime a short video of the quick-step in action miling the handle boss stop faces.

[youtube1]https://youtu.be/S_4RalQNLQw[/youtube1]

[steamer]

Hey Bjorn,

What material did you use for the leadscrew?

Nice finish on that...

Dave

[Bjorn_B]

Leadscrews i made in posts above will be discarded I think, as I remember they where made of ordinary EN1 quality.

[steamer]

Leadscrews i made in posts above will be discarded I think, as I remember they where made of ordinary EN1 quality.

OK....I think in the states that would be 1018 CR.....wow   Nice finish there!

Dave

[Bjorn_B]

Most of my time seem to be made up of stepping between the mill (or lathe) and these two sheets of conversion tables. I made these in excel and stapled them to the wall between the lathe and my marking out space a long time ago. Been of endless help for me (metric head, metric machinery making mostly things measured in inches)..

20170909_173845 by Bjorn Bursell, on Flickr

20170909_173853 by Bjorn Bursell, on Flickr

[Bjorn_B]

Bit of time in the workshop today, started on the gearcase block. A piece of aluminium squared up, marked up and drilled/bored/reamed

20170910_094523 by Bjorn Bursell, on Flickr

Piece is then transfered to a four-yaw for scooping out room for the gears

20170910_095808 by Bjorn Bursell, on Flickr

Decided to play a little with the qiuck-step here, this is the lowest possible spindle speed my lathe is capable of, it is about 8,5 rpm

[youtube1]https://youtu.be/brdW4ami4_k[/youtube1]

Turned out to be a good thing, the recess would call for a trepaning tool otherwise

20170910_122400 by Bjorn Bursell, on Flickr

After this, turn around in the four-yaw, and more lathework..

20170910_121900 by Bjorn Bursell, on Flickr

I miss 2 countersinks, 9 and 10mm, 9mm is needed for this! 

20170910_123255 by Bjorn Bursell, on Flickr

[Bjorn_B]

Micrometer collar day..

Nothing really unusual, with a 2mm pitch leadscrew, I i decided to do 40 divisions, just as the standard myford metric top slide but numbered for infeed rather than diametric numbers (myford collar numbering idea on the metric topslide makes so sense to me at all, it is numbered 0 to 35..)

Setup for scribing the collar
20170912_172314 by Bjorn Bursell, on Flickr

In progress. Long line every full mm (2 in total), intermediate lines every full 0,1mm and short lines 0,05, 0,15mm and so on
20170912_172319 by Bjorn Bursell, on Flickr

After lines are scribed, drilling, boring and reaming a half inch hole thru and some additional boring for a recess
20170912_180555 by Bjorn Bursell, on Flickr

Happy with the satin finish after using a scotch-brite type wheel on a airtool
20170912_181513 by Bjorn Bursell, on Flickr

Oh, there is a shallow recess inside the half-inch bore for the locking pad, after thinking a bit on how to do this with a lathe tool, i found a woodruff cutter that passed the bore, time for the Quick-step again!
20170912_183127 by Bjorn Bursell, on Flickr

Setup for stamping numbers
20170912_183344 by Bjorn Bursell, on Flickr

Numbering is half-descent at least..
20170912_190320 by Bjorn Bursell, on Flickr

After parting of, mounted on a small chuck and corrected for length, the radius was done with a hand graver
20170912_193620 by Bjorn Bursell, on Flickr

Done!
20170912_193749 by Bjorn Bursell, on Flickr

[Bjorn_B]

As noted a few posts back, a 9mm countersink along with its mate has gone missing so todays task was to make a new 9mm one..

This book was dug out of the bookshelf..
20170913_183150 by Bjorn Bursell, on Flickr

And after intense studying, a piece of silver steel was massaged by the quick-step (yes it's featured again) after being turned to dimension
20170913_171623 by Bjorn Bursell, on Flickr
20170913_173303 by Bjorn Bursell, on Flickr
20170913_174152 by Bjorn Bursell, on Flickr

After some additional milling for the keyway, it was hardened and polished (somewhat)
20170913_181155 by Bjorn Bursell, on Flickr

And here is the new guy amongst the crew (yes, it is straight fluted...)
20170913_181145 by Bjorn Bursell, on Flickr

So, the gearcase now features countersunk holes!
20170913_183113 by Bjorn Bursell, on Flickr

[Bjorn_B]

Outline milling of gearcase parts today. As I don't have a good rotary table (but a sturdy dividing head) I chucked up a aluminium stump, faced of at both ends true and square. Drilled, bored and reamed a half inch hole in the centre and transfered this to the dividing head to use as a rotary table/milling fixture.

This is the aluminium chunk with the centering stump after all milling was done.
20170916_213942 by Bjorn Bursell, on Flickr

And this is one part of the gearcase being milled, the steel block was milled in this fashion too, but I forgot to take photos...
20170916_213856 by Bjorn Bursell, on Flickr

[Bjorn_B]

Back at this again, got the leadscrew done today! It is a piece of commercial left hand 2mm pitch leadscrew that I got from accugroup (https://www.accu.co.uk/en/)

This was turned down at the end and loctited to a piece of bms. To make this true to the leadscrew I thought up this setup to drill with a centre driill at the end, running true with the axis of the leadscrew.
20171018_170226 by Bjorn Bursell, on Flickr

After that was done the piece was supported by the tailstock and about 50 mm of the outmost end turned concentric. The whole thing was then turned around and clocked up to run true in a four-yaw, end of leadscrew this time supported by the tailstock and the thread and o.d. was done. Result is shown here
20171018_190331 by Bjorn Bursell, on Flickr


 

[Bjorn_B]

Handle time:

Modified the stock top slide handle, GHT mentions setting it up in a four-yaw, I did not think this was feasible, but it really was super simple. My self centrering four-yaw seldom gets used, but for this it was perfect!

First a couple of passes with various drills
20171019_183255 by Bjorn Bursell, on Flickr

Then a bit of boring
20171019_183802 by Bjorn Bursell, on Flickr

After a final pass with a reamer this is the result, the top slide is locked and not useable until I'm done now..:
20171019_185434 by Bjorn Bursell, on Flickr

[Stuart]

Bjorn

we both have the same lathe and you have confused with your comment about the top slide dial as supplied you state it has 35 divisions , ok it is numbered to 35 but there are 5 more ticks to get back to 0 just the same as the cross slide



just had to check it out so 0 to 0 is 2 mm. 0 to 20 is 10mm


anyway nice work on the GHT project I have no made one Burt your idea of a commercial 2mm pitch screw has peeked my interest.


we spoke In one on your other thread about the dog clutch glad it works well mine certainly does oK but I used oil on for the two gears

Stuart

[Bjorn_B]

Hi Stuart!

Yes, I was a bit unclear about the topslide collar. The numbering is an issue for me, it is really numbered for diametric dimensions (0-40), but how would someone use this? The cross slide is in my view the main thing for diametric work and the top slide can't even be set at 90 to the bed because the handles would in the stock configuration clash anyway. The top slide is more for short tapers or threadcut infeed (both direct reading). I have now a direct reading (0-20) on the new collar that works better for me


Anyway, some small work today with the leadscrew nut (bought with the leadscrew), I Believe GhT mentined this was to be made on the faceplate, but a mill is so much easier. Bored out the hole and drilled the small holes in a piece of scrap brass I found. The top surface was then faced of to thickness.
20171020_175730 by Bjorn Bursell, on Flickr

I rough cut this on the bandsaw and silver soldered the thing together. Will be made to look nicer in a later stage.
20171020_182623 by Bjorn Bursell, on Flickr

[Stuart]

Thanks for the update Bjorn

I understand now your logic with the dial

its the same setup as the cross slide metal removed equals the dial setting

but I do use mine for diametrical work with it set to 90 deg. when I have the taper attachment connected and the cross slide un bolted

so its user choice I think I will leave mine as is

one point to think about while you play with the top slide . I have made a new one up ( kept  the old one just incase ) but I made it 1.5 mm thiner , my logic for this is I use the small Aa size multifix and my standard 10mm tools were a bit high now I have a bit of lee way ( it was the same problem with the Myford QC as you have ) I also offset the hole to the left by 5mm to give a bit less over hang .

I normally have the top slide over at approx 30 degrees so it suits my needs

keep up the good work always a pleasure to read and view your work

[Bjorn_B]

Been thinking of facing the whole top surface of my top slide of a bit, but a new piece could be made quite easy as you did! Would be really nice to be able to use 12mm toolholders... And a multifix would be nice too

Anyway, cleaned up the nut!

20171021_092242 by Bjorn Bursell, on Flickr

(counterbores are a bit oversize, I could not find anything to use in the correct size..)

20171021_100404 by Bjorn Bursell, on Flickr

The top casting of the top slide needs a bit more clearance for the feedscrew setting nut/slide bushing. So a ball end mill was put to use..

20171021_131416 by Bjorn Bursell, on Flickr

The rest of this days work is the locking screw and lock pins for the dial

20171021_104558 by Bjorn Bursell, on Flickr

Vice in a vice, I did not want to disturb the setting of the milling head to mill a 45 degree angle..
20171021_122502 by Bjorn Bursell, on Flickr

All parts are now in the small parts cleaner (cast iron dust here and there) I think I'll be able to assemble this tonight

[Bjorn_B]

I was a bit quick and had forgot to drill and tap holes for the backstop (used for tight internal threadcutting and boring jobs)

So Setting up on the mill again. This is at the end of the vertical capacity of my mill (my mill has no knee) so the setup as done with a myford type angle plate from the bed. An alternative would perhaps be to use the collet chuck to gain some Z height, but I'm a bit lazy..

20171021_172106 by Bjorn Bursell, on Flickr

Started assembly but i have a binding issue somewhere, need to sort that today.

[steamer]

Looking good Bjorn!

Dave

[Bjorn_B]

After finalizing the position of the excentric sleeve for the lever, The stop plate hole was drilled in the main body. The stop plate will be bandsawed/filed to shape later..

20171022_100135 by Bjorn Bursell, on Flickr

After fiddling about a bit, this is the top slide in forward position
20171022_102547 by Bjorn Bursell, on Flickr

And retracted:
20171022_102551 by Bjorn Bursell, on Flickr

Next interesting job is to set gear mesh, there is a excentric bushing for the primary shaft that is set in position in this picture
20171022_123351 by Bjorn Bursell, on Flickr

This is more or less the whole thing done, the stop plate needs to be made to shape yet.
20171022_124457 by Bjorn Bursell, on Flickr

Another shot
20171022_124511 by Bjorn Bursell, on Flickr

[Bjorn_B]

Could not resist, making the setscrew for the backstop (yes I have a die for this..)
It was a bit clumsy to do this one-handed 
Only the stop plate for the handle to do now 


[youtube1]https://youtu.be/oqe6QJD-TT4[/youtube1]

[sco]

Very nice work Bjorn!

Simon.