mini ball turner.....

[Bernd]

Actually Ralph I own 3 saws. Two grizzly bandsaws and a powered hacksaw. If shipping and taxes weren't so much I'd be willing to ship you the hacksaw since I don't need it any more.  ;D

The part was salvageable by the way. I just milled the bottom and rescribed the lines. Now all I need to do is cut it out, finish mill and add the cutter and I will have a ball turner.

Thanks to your persisten nagging to get it done. 
 
Also watch HMEM for my next engine build. I'm going to show how to use a sacrificial aluimnum milling table. It'll be a while yet though.

Bernd

[Divided he ad]

Ok then.... On with the show!!

Just to make it clear... I am not (against popular belief) perfect....  :-\

The pictures already posted show the turret made to 40mm dia. this has become an issue when the drillings for the fixing points were made. They cut into the edge of the recesses and made small but noticeable swarf traps... This will not do.

So last night I started re-making the turret, larger50mm dia and re-machined the base slightly to allow the bolt holes to be within the recess for the turret.

A few pics to get me up to date.

new part cut (by hand!!)
 

the part faced and then the outer edge cleaned off using super glue gel to hold it to the chuck.


The part removed, the chuck and part clean up easily.



The part sized and ready for a little lapping. I put some blue into the grinding paste so it would photo' easily  



To lap it I used a fixed centre against the brass base and applied pressure via the tailstock whilst the machine was running, you know when the lapping is being done as the bit you are pushing stops spinning with the one in the lathe, This may not be the best way to do this but it worked... And just a little cleaning up on the base where the centre was pushing it. (this might not work if the base were steel?)



So as of last night I have this to show for my efforts...



Hopefully i will get some meaningful work done on this very soon. It has to be finished.

How's yours going Bernd?



Ralph.

[Divided he ad]

Well I put some time into this tonight.... Got the new turret mostly finished.

It was all about the setup.... the machining took min's!

Tool post slot.


Relief for grubscrew holes.


Handle hole


Grubscrew holes


Where we're up to....



A piece of square machined 1/2 " ali plate has been sent off to the new owner so that it can be marked using a sharp point turned in the 3 jaw ... Slide the plate across the point whilst holding it firmly to the saddle and it should give me an easily transferable (via height gauge and surface table)  scribed line.... Just waiting on it's return now!!


Ralph.

[Brass_Machine]

Thats looking very good! I gotta start mine one of these days. Maybe tonight...   

[Bernd]

Looking good there Ralph. 

You've got the second one almost done and I haven't even finished my first.  :P

Bernd

[Divided he ad]

Well gent's I came to the theory - a job that needs to be done that didn't work well and has become delayed will stop your progress on other things and bring you down....

So I came up with a solution, do a little on something that will make you very happy, then when you do a bit on the awkward job you are in good spirits and you get it done quicker and you are still happy at the end of it! 


Works for me anyway.... I'm still happy now  ;D  ;)


More on this next week too.

Ralph.

[Bernd]

You're absolutley right about that Raplh.

So that's what I did. I worked on something else. Then I went back to finish this.

 

Can you guess what it is?  ;D (sorry for the blury pic)

NO! Ok here's what it is.  ;D




And to show that I did it:



Not quite a ball, but darn close for the first time. YES?

I call this the MK I. It was just to try out the idea of a tool such as this. I see lot's of projects now with balls on them. (eh hem No pun intended)

Now back to Ralph's mini turner.

Bernd

[Divided he ad]

Sweet tool Bernd....!! Worth the effort?

If you would like to view the post I did on set up of the tool it is on the HMEM board, last few pages of the 'Nose cone - ball turner' post about half way down the last page in fact.

http://www.homemodelenginemachinist.com/index.php?topic=1721.45 (hope it's ok that I link to this?)

You will get a very good, very close ball from this method.


Looks like your not too far off now anyway... Nice first attempt... My first one looked like a rugby ball!!! (a football to you guys)   ;D



That lathe looks remarkably familliar!!!? I think a saddle lock is a future project though.... The allen key did my nut in!! (drove me crazy)



I look forward to seeing your.....     Erm no!  I am looking forward to your future projects with knobs on  ;D


Ralph.

[Bernd]

Thanks for the nice comments Ralp. 

Went back and "reread" your steps. It's almost to a "T" what I did without the marks. I sort of eye balled it. That's why it came out close.

The lathes are of the same design. Mine's a Grizzly.

I think I'm going to make a ball turner for the Sherline so I can make smaller knobs. 

Thanks again for the push. I probably would have never made one, but after seeing one of your video's I had to have one. 

Bernd

[Brass_Machine]

Bernd

You have shamed me into starting mine for my mini lathe! That came out very nice! I am duly impressed.

Very nice. I will start mine this weekend. I have to finish up some Halloween props for neighbor (will be doing either a gallery or log on them) first.

Eric

[Bernd]

Ya, thanks. I think you should blame Ralph. After all he's the one that started it all.   

You'll realy like that ball turner once you get it done. I didn't think something like that could be so much fun. It's fun to whatch as the ball materializes from a piece of long round stock into a ball.

Bernd

[Divided he ad]

I knew you would get the bug Bernd 

I would be honoured to take full responsibility... But I would then have to blame Steve Bedair!!!!  ;D


Eric,

I'll sent you my rough sketches if you like, They might help you with yours since a few errors have now been ironed out on my version.

I'll get some time on it soon... Honest.


Ralph.

[Divided he ad]

Ok, when last I left this post I had just mostly finished the new turret. Well I got a little done today on the tool post.

The ali plate I sent off returned yesterday and I started getting all the heights etc set and correct.

I know some of the times are incorrect for the order of the acts described, but my phone once again decided it did not need to record all the photo's I took... So I had to use some later images to show the pictorial that goes with the write up!!!

I used the vernier height gauge to get the exact heights of the scribed line on the block, and then used it to get the exact heights of the surfaces of the main tool body.(gauge not in contact at time of photo!)





Then, I milled the tool post to the correct width for the turret. Then used the grubscrews to mark the tool post so that a relief groove could be added in the correct line to stop the burrs caused by the grubscrews from fowling the sides and making the tool hard to adjust.







I marked the tool post exact height and then mounted it in the main body and checked it against the height recieved on the ali plate... Thankfully all calculations worked and it was exactly as it should be.... I like exactly at this stage 



Finally for this evening. I milled the toolpost to height and found it's centre, then centre drilled it. I am waiting upon some fixings and tap's now before I drill any further.



Well that's it for this part of the post.... Hopefully this time next week We might have a winner!!??  (depends a lot on the Royal mail!!)



Ralph.

[Divided he ad]

This post.... The scary task of mounting the tip  I took my time and still made a dumb ass mistake... Not detremental though.... Phew!!!!!

Well the pic's tell all so here they come.......


First the tool post was drilled and tapped for a M2.5x0.45 tread.



Then the new tip is inverted (due to it tapering upward when the right way up) and scribed around.



Ending up with this.



The tip depth is measured (2.53mm) and the centre hole is bored using a 6mm slot drill.



Then the hard part..... I have no CNC and there fore the milling out of the angles is all done by hand! .... Enter my error #1.... Yes I turned the damn X axis wheel the wrong way :o It is noticable but is not going to interfere with any operation the tool will perform. So it stays!



Then when all that is done, in goes the tip.. Note the slight error in the lower right angle of the cutout in the tool post..... Dumb mistake!





Then it is held firmly in position using a screw and the height of the tip is checked.

All Good the 56.15mm height that was desired is clearly there 
First convex cutting side



Then concave side



Glad all that was done!!!!



Now then there was some other stuff achieved .... The bolts for holding the tool to the cross slide were turned to size held in an arbour. Also reduced the head height.








Then I made two little holes through the turret to allow the tool to be attatched to the machine (since it comes in two using a screw from the base, this is the only way to fix it down.)
And they had to have swarf covers to stiop nasties falling into the rotating area of the tool....




Obviously some finishing required!..... I'm thinking this will be done by next week   ;D




Ralph.

[Bernd]

Not bad for "manual" CNC slot cutting. 

Bernd

[Divided he ad]

Thanks Bernd.... I tried and nearly got a clean job out of it!!

Why do you always turn the wheel the wrong direction right near the end?!??!



Well it appears that I may have a rival build on the go too.....!!

We shall see if I get put to shame on the time taken ehh!!??    To arms!!! 



Ralph.

[Bernd]

Thanks Bernd.... I tried and nearly got a clean job out of it!!

Why do you always turn the wheel the wrong direction right near the end?!??!

I think that guy Murphy has something to do with.

Well it appears that I may have a rival build on the go too.....!!

We shall see if I get put to shame on the time taken ehh!!??    To arms!!! 



Ralph.

Ya, I see that. I think your safe on that count though. 

[Divided he ad]

I think that guy Murphy has something to do with.

Your not wrong there Bernd, Talk about sneaking up on you at the last moment!!

Well as I said it is still a very secure fit.... Should be a very usable solid little device.

Ya, I see that. I think your safe on that count though.

I Don't know.... I think Eric might be posting pictures taken last month so that he can suddenly produce a working tool in a matter of days!!!  ;D    ;)  Or maybe that's just my head running away with itself again???!  It does that!!   :-\   


I think it should be good to see the design differences etc.



Ralph.

[Bernd]

I think it should be good to see the design differences etc.

Ralph.

I see the differences now. Eric's machine is a 7" X 12" lathe (I think) and mine is a 9" X 19". I have T slots on the cross slide and Eric dosen't on his. So bascially the mounting plate is different. The top end should be simular.

Bernd

[bluzboy]

This is a very cool tool!!!!   One of the things that I'd like to be able to do is turn nose cones for rockets.  Ogives (both Secant and Tangent Ogives) are very popular designs.  Since ogive shapes are basically sections of a circle, it seems to me that this device can be used to turn Ogive type shapes - using the tool in an offset fashion such that the tool is not centered on the X axis (for Tangent Ogives), and not centered on either X or Y axis for the Secant Ogives.  It would also mean the tool would have to be designed for a much larger radius (i.e. a 'standoff' distance) but we would use only a section of the circumference (depending on how oblique the ogive is to be).   Have you given any thought to this geometry and the attendant tool mounting issues? 

Thanks!!

Paul

[Brass_Machine]

Hey Paul,

Welcome to the group!

Ralph will have to answer more on your question, but from what I have seen it is very possible. I have seen people make propeller nose cones with these things.

Eric

[Divided he ad]

Hi Paul,

I've made a little ogive in the past.... Still have no use for it!! But I was kinda challenged so I made it!

I don't know what the largest obtainable ogive would be (never tried) but I know the principle of turning one with one of these tools.... Look here :

http://madmodder.net/index.php?topic=282.0

Hopefully you will find something of use in there.

I can talk you through the set up I used easily enough. Not too sure about all your other questions... Never thought of trying to be honest!

What do you make or have you made Paul?  Do you have any pictures to show the forum?


Ralph.

[bluzboy]

Thanks, Eric and Ralph...

I am a total nube to machining ... I'm just doing research right now, preparatory to getting gear - just what I need - yet another hobby - but I have been interested in this for years.  I started buying accessories for lathe and mill - so that is a guarantee that I will be getting the machines soon enuf.   I have my eyes on a Sieg C4 right now.  And for a milling machine, probably a Super X3.  The big constraint right now is space to dedicate to new tools, so I'm pretty much limited to benchtop gear.    My initial tie-in to other hobbies is rocketry, hence my interest in turning the ogive nose cones.   I'm also interesting in turning some nozzles - not really functional nozzles, but the kind that are used for motor retention and 'effect'....  My elderly uncle has a shop out behind his house with some old, old, gear in it, so I'll have something to share with him - he enjoys making brass steam engines.   His shop is set up with old belt-driven machinery - common power drive for several tools, like the old machine shops.   I'll keep you posted on my progress on getting going - it will probably be a couple of months before I'm really underway.   Some really cool ideas in this forum - like getting metal from the scrap yards.   Piston crowns!!! no kidding!!!

Professionally, I am a software designer/developer, so I can easily see this heading towards CNC, if the hook really gets set in me.... ;-)

Thanks again for the welcome...

Paul

[Divided he ad]

Ok..... So I finally got my rear into gear and finished this little puppy..... Yes that was 'finished'!!   

I'll let the pic's do most of the talking  ;D




Sorry about the slight blur!!!


The reason for the not as pleasing look of two holes and covers in the places they are... Well I didn't want swarf falling down into the rotating area as it probably would if the holes were under the tool post (one would often get exposed when cutting a larger convex or mid size concave patterns.) of course that could be remidied in a few different ways.... This was mine.


Just to note what tonight entailed....

I finished the tool post to the level of the turret.

Took a file and removed most of the tool marks, and used emery wrapped around the file for a fine finish.

I then marked the tool tip edge onto the tool post (scribed line visible just in front of the tip in the downward shot) I used a square to find the piont directly inline with the tip and then used the square to scribe a line across the tool post.

The turret was next for marking. The centre was found and marked and then using the square against the grubscrew relief shelf I scribed a line on both sides of centre.

The lines on the tool post and turret are used for the set up of the radius of the ball that is to be turned.
Measure the dia' of the bar being used as a blank, halve it and make the distance between the lines that result. The tool is then set for the radius it is to turn.... Giving a ball of the dia' double that of the tool setting.

Then I thought I'd make it shine a little  8)

Now just to contact the new owner for the address etc and the job is all over!!!
Oh, And obviously I'm going to throw in a tapped slug of brass bar.... Everyone has to make the first ball to be the handle   



Next....  I can get some serious me/fun time in .... Wind ball here I come!!! 



Ralph.

[Brass_Machine]

Nice job Ralph!

Polished even 

Eric