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cadwiz
10-28-2006, 02:27 PM
A few weeks ago there were several threads floating around regarding collet closers. I took some time off from the mill restoration to complete mine for a Grizzly G4003 12x36. The 5MT to 5C adapter was purchased from Grizzly, Torrington thrust bearing and washers purchased locally for $10, everything else made by me.
Enjoy, Cadwiz (Clinton, La)
http://i33.photobucket.com/albums/d70/cadwiz/CCK2.jpg
http://i33.photobucket.com/albums/d70/cadwiz/CCK3.jpg
http://i33.photobucket.com/albums/d70/cadwiz/CCK4.jpg
http://i33.photobucket.com/albums/d70/cadwiz/CCK5.jpg

John R
10-28-2006, 02:34 PM
Looks great. Maybe you could show a sketch or two.
John R

cadwiz
10-28-2006, 03:17 PM
Ask and ye shall recieve. This is the basic template I drew for the hub/handle assembly (6"x1" T6061 plate with 2.5" T6061 round bar). Everything else was done on the fly (drawbar internally threaded to 5C collet dimension, spindle adapter threaded metric to match the spindle threads, retainer ring/drawbar ID/OD threaded 1-3/8"x18TPI). Sorry if it doesn't show up very well, I usually only exchange ACAD files by DWG, DWF, or PDF. I haven't found a good way to post them through photobucket. Evan probably knows a better way.
Cadwiz
http://i33.photobucket.com/albums/d70/cadwiz/5CColletCloser.jpg

Timleech
10-28-2006, 03:38 PM
Ask and ye shall recieve. This is the basic template I drew for the hub/handle assembly (6"x1" T6061 plate with 2.5" T6061 round bar).
Cadwiz
http://i33.photobucket.com/albums/d70/cadwiz/5CColletCloser.jpg

Is it common practice to use a fancy thrust bearing? Mine just bears straight onto the end of the spindle, as did the one on my old lathe (Colchester)

Tim

sidegrinder
10-28-2006, 03:58 PM
Nice job! What kind of runout did you end up with?

cadwiz
10-28-2006, 05:07 PM
Tim, the three reference articles I researched all used needle thrust bearings. For the cost I figured it couldn't hurt. Seems to give a nice smooth feel when tightening the drawbar.

Sidegrinder, I just measured runout. Surprisingly it looks like around 0.0005" or less. My new indicator was just barely moving between the smallest division marks. Either it's crap or I did a fairly good job on the machining. Not that I really need the accuracy, it's just that the 6" and 8" chucks were getting in the way for small parts machining. A nice new addition to the tool selection at hand.
Cadwiz

skeeter
10-28-2006, 10:55 PM
Hey Cadwiz,

Very neat job, well done.

Could I impose on you for the part number from Grizzly.(MT5 to C5 adapter) I could not get anything to come up with the search I did.

I have a C5 chuck, but would like to try to built one of these.

Enco's site is down so couldn't check their place.

TIA

cadwiz
10-29-2006, 07:27 AM
Skeeter, Grizzly adapter part# is P4026001 for $29.50 (MT5-OD x 5C-ID). It's a replacement part for the G4026 lever collet closer and comes with the indexing pin already installed. It doesn't show up on their website because it's a replacement part and not a standalone item so you have to call to order. I found it by downloading the parts list for the G4026.

Here's another pic of the assembled closer off the lathe:
http://i33.photobucket.com/albums/d70/cadwiz/CCK1.jpg
Cadwiz

torker
10-29-2006, 09:28 AM
Cadwiz...I keep looking at this thing and I'm missing something. The thin ring...what are the two divots for? How is it held onto the assembly?
It must be covering the main part with the three flat head screws but I'm not really seeing the purpose of it or (again) how it is held on. Funny what a lack of sleep will do...
Thanks!
Russ

cadwiz
10-29-2006, 10:47 AM
Torker, the retaining ring and outboard end of the drawbar are threaded 1-3/8x18 (the threads in the ring don't really show up in the photo). The divots were drilled so I can use a face spanner if necessary to remove. Yesterday's testing has so far proven that the retaining ring keeps the handle/hub snug as the backside recess bears against the thrust washer and the other washer bears against the spindle adapter. So far I haven't needed the spanner, but I put the holes there just in case. Being aluminum I didn't want to bugger it up if it becomes cranky. I broached the hub (first time I've done that!) and milled the slot for the key to act as a driver to drive the drawbar so it will tighten into the collet. When I was researching how to do this I kept asking myself the same thing: How does it stay on? The answer seems to be a friction fit from the 5C taper. I guess this is correct, it seems to work properly. I pretty much used Don Kinzer's design for this project:
http://www.kinzers.com/don/MachineTools/collet_closer/
The only changes were that I made a 2-piece handle/hub assembly instead of machining a solid chuck of 6" aluminum and I threaded the spindle adapter instead of using a slip fit. As such, the three flathead socket screws holding the hub to the handle prevented me from counterboring a recess in the handle for the retaining ring to fit in.
Cadwiz
(oh yeah, how's the mill restoration going? I'm starting to disassemble/clean the head of mine today)

BillH
10-29-2006, 11:54 AM
Cadwiz, beutiful work, looks great!
I was thinking about doing the same thing for my SB 9" lathe but with 3c collets, then I noticed LittleMachineShop is now selling new 3c collets, tubes, and drawbars for a good enough price to not need to make my own.

torker
10-29-2006, 12:32 PM
Cadwiz...Thanks for your time!
Now it makes sense. I couldn't see the threads on the id so it had me fooled.
Nice job!
The ol' mill needs a bit of cleanup on the table and leadscrew, other than that it is finished. Waiting to score a deal on a rotary phase converter and still have buy a belt.
Biggest problem is ROOM! I really have no place to set this machine up yet.
Russ

wierdscience
10-29-2006, 12:32 PM
Nice work! Are you thinking of knurling the OD of the handwheel? I had to do that on the two factory made closers at work.A little coolant and the plain ones get slick.

cadwiz
10-29-2006, 02:12 PM
My knurling tool is too small for knurling. One of the reference articles I found on the dropbox showed grooves made with a ball endmill. I figured I'd give it a chance without the grooves first since I don't use coolant. If need be I'll put a series of grooves around the handle perimeter.
Cadwiz

Timleech
10-29-2006, 02:41 PM
What about cutting some 'spokes' in the wheel to help with gripping? less likely to cause an injury than knurling or grooves on the periphery, IMO.

Tim

dp
10-29-2006, 03:10 PM
A checkered or fluted hardwood rim overlay would look great and be very functional. But wood that won't make splinters :)

Or just fluting the existing rim with a round end mill would look nice and improve the grip.

John Stevenson
10-29-2006, 03:53 PM
The one on my CVA has the fluted grips in but even that isn't enough at times.
In the outer rim there are three holes to allow a bar to be fitted to give it the final tweak.

They are probably original as the CVA has a spring loaded detent, next to the handwheel, that allows you to lock the spindle whilst tightening the collet.

.

cadwiz
10-29-2006, 04:40 PM
Sir John, the hole idea is spiffy for sure. If push comes to shove I have plenty of meat left in the handle for some helper holes. I'l keep that in mind for future adjustment.

Cadwiz

Timleech
10-29-2006, 04:50 PM
The one on my CVA has the fluted grips in but even that isn't enough at times.
In the outer rim there are three holes to allow a bar to be fitted to give it the final tweak.

They are probably original as the CVA has a spring loaded detent, next to the handwheel, that allows you to lock the spindle whilst tightening the collet.


John

I've got two CVA handwheel drawtubes. Both of mine are spoked wheels with smooth rims.
Sadly I didn't get any of the rest of the collet gear :(

Tim