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Timbuck
11-20-2011, 09:25 PM
Just in case anyone is interested:eek:
I needed a "worm wheel" for a device I'm building (To be shown at a later date)..so I made one out of a disc of Nylon..I mounted it on a block on the cross slide table level with the centre line of the Little Drummond lathe..Gripped an M10 Tap in the chuck..I proceeded at a slow speed feeding the disc into the side of the Tap until it reached the required depth..And it turned out nice..:D
IN THE LATHE CUTTING THREADS
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT0003-14.jpg
FINISHED JOB
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT0007-4.jpg

finkdaddy
11-21-2011, 04:29 AM
You are a madman!! :D

Rick Turner
11-21-2011, 04:33 AM
Ken, how do you make sure that the start and finish match up on the worm wheel? In other words, how do you not wind up with a fractional tooth? Or do you not need complete and repeating revolutions of it on this project?

Gear cutting is a real science...

resoman
11-21-2011, 04:37 AM
That is very clever, you never cease to amaze me!!

Ambient Doughnut
11-21-2011, 04:45 AM
Ken, how do you make sure that the start and finish match up on the worm wheel? In other words, how do you not wind up with a fractional tooth? Or do you not need complete and repeating revolutions of it on this project?

Gear cutting is a real science...

I was just thinking that myself and wondering how to phrase it...

Timbuck
11-21-2011, 05:09 AM
You have to calculate the pitch circle diameter of the thread..In this case I started at 42.85 mm outside diameter...and took the tap in 4 mm to an inside pitch diameter of 34.85mm x Pi (3.142) = 109.5mm circ ... M10 coarse thread = 1.5mm pitch divide 109.5 by 1.5 and this gives me 73 teeth exactly...simple :)...or you can just keep your eye on it while cutting and stop when it gets there..if you look carefully at the cutting pic you can see the step in the thread, when that step decreases to nothing you're there.

tonewood
11-21-2011, 06:32 AM
Lathe improvosation. Nicely orchestrated. Looks important.

Rick Turner
11-21-2011, 06:32 AM
Brilliant, Ken...

I love the contrast between the math and the practical!

Thanks, and much appreciation and respect for your machinist's background. I took a couple of machine shop courses at a community college many years ago, and loved it. Didn't get to gear cutting, but I got the overview.

Timbuck
11-21-2011, 07:32 AM
I didn't invent this method .. I was first shown it when I was an apprentice in the 1950's It's called "hobbing"... it's not the best way to do this job with a tap "but it works" I have done conventional gear cutting in the past and it can get very complicated...Here is a thread from another forum with more detail on how this method is applied.
http://bbs.homeshopmachinist.net/showthread.php?t=27680

Timbuck
11-21-2011, 07:48 AM
Anyway..I started to put this worm gear to use..I made a few more bits and now it's assembled and "so far" looks like this...No! it's not a hole cutter :)
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT0015-3.jpg
And this is where it fits in the main assembly. Can you work out what it's for yet ??????.. It's to do with music but not ukuleles.
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT0016-6.jpg

Steve vanPelt
11-21-2011, 08:21 AM
I was thinking a dish spinner for sanding ribs, but since it's not for an uke, ...... Are you making a player piano?

douginnc
11-21-2011, 08:23 AM
I'm thinking music box of some sort. Or, a street organ?

Liam Ryan
11-21-2011, 09:26 AM
Brilliant, Ken...

I love the contrast between the math and the practical!

I totally agree. As a schoolboy there were those who crowed "but when will we use all this maths in the real world", and they were right. You don't need any maths to pour beers or wash dogs....................

Timbuck
11-21-2011, 09:44 AM
I totally agree. As a schoolboy there were those who crowed "but when will we use all this maths in the real world", and they were right. You don't need any maths to pour beers or wash dogs.................... Every time you look at the calender..or look at the time... or go shopping..driving along looking at the speedo or petrol guage..measuring for cutains, playing darts, Pool, gambling, Making ukes, checking your pulse, cooking a chicken, counting your wages, looking at the bank statment etc: etc: you are subconsiously doing Maths.

vanflynn
11-21-2011, 10:17 AM
I totally agree. As a schoolboy there were those who crowed "but when will we use all this maths in the real world", and they were right. You don't need any maths to pour beers

But you do need Physics to open beers

gnordenstam
11-21-2011, 10:24 AM
Looks like you're building a cylinder player - as in an Edison Phonograph or Columbia Graphophone.

Timbuck
12-01-2011, 02:09 AM
Time to reveal All

My Son Mike came to me with a problem, He wanted to make some accuratly shaped foam cones for some electronic drums he is designing..
like these
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT0003-16.jpg
To do this Job..We tried Hot wire foam cutting (Too slow and the wire kept losing heat or burning out) CNC routing machine Way too slow and left a bad finish..Finally my new jig thingie...Well see for yourself..just click on the image.
http://i219.photobucket.com/albums/cc143/shiregreenbod/th_PICT0001-14.jpg (http://s219.photobucket.com/albums/cc143/shiregreenbod/?action=view&current=PICT0001-14.mp4)
Success! .....They fit under a mesh drum head and transfer signals thro the cone to a pick up transducer in the centre of the drum
here is one in in place ready for testing.
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT0004-12.jpg
After a final bit of tweeking & modification we are now ready to go ..the first few "test cones" are just made from scraps glued together to get the set up right...When the foam sheet material arrives we can go into proper production.
http://i219.photobucket.com/albums/cc143/shiregreenbod/PICT0039-3.jpg

Caboose66
12-01-2011, 02:24 AM
I'm not a luthier... and I don't play one on TV (or, the "Tele" as you may call it) but these are the types of threads that keep me coming back to this forum. I love the strictly uke-related threads as I hope to try my hand someday, but these general threads that showcase the broad mechanical/electrical/you-name-it knowledge and ingenuity are very, very interesting.
I also have to say that the experience and brainpower that exists in those that have decided to make ukulele (or guitar) building their profession (or serious hobby) gives me a good feeling.
On another note: Ken, I've read a few of your posts where you've referred to projects your son is working on that you've been enlisted to provide your input. In my opinion, this is too rare these days. It's so encouraging to see/hear of knowledge of this sort, born from real-world experience, being passed along. I feel the same way about those who have made their craft their livelihood and are generous in passing it on even to the point of letting others run their own related businesses (you know who you are).

Hats off to you guys!

Dean

gyosh
12-01-2011, 03:10 AM
I grew up the son of a machinist and was constantly amazed at how my dad could come up with seemingly simple solutions to very complex problems.

You sir, are a genius!!

Thank you for sharing,

-Gary

funaddict
12-13-2011, 04:30 AM
Pretty cool! Until you showed us what it was for, I was going to say that here in the US, we just roast our marshmallows on a straightened-out wire coat hanger! Why didn't you just machine them on the lathe? Or if the foam is to soft for a lathe tool bit, maybe a router mounted to the cross slide? I am constantly amazed by your invention and innovation.
Alan

Rick Turner
12-13-2011, 05:00 AM
Open cell foam or closed?

The reason I ask is that one of the cool tricks for machining relatively complex shapes in honeycomb aluminum or Nomex is to fill the cells with water, then freeze the whole blank, and then machine it. The ice supports the thin webs of the material being machined. It's like machining ice cubes. No coolant needed, either! Thaw and use...

Yes, my use of the word "cool" was an intentional pun... and check this out: http://www.youtube.com/watch?v=kh7RrlazaRc

resoman
12-13-2011, 05:15 AM
That trumpet vid was really, really interesting!!

Pete Howlett
12-13-2011, 07:38 AM
Ditto - thanks for the link Rick