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Sportandmiah
12-12-2010, 11:14 PM
I'm making a 3.30" dia faceplate for my Sherline lathe, and am curious what you think the tapped hole spacing should be. Is there a certain pattern I should follow that works well for most everything? Or should I just tap as I go when needed?

darryl
12-13-2010, 12:16 AM
I'd probably machine three or four concentric circles on it, one at 3/4 inch radius, one at 1 inch, one at 1 1/4, and one at 1 1/2 inch radius. Then scratch cross marks, two perpendicular for a square pattern, then identify one of those as common and scratch two more from center outwards at 120 degrees from the common. That gives you overlapping marks where you'd center punch, drill and tap. The layout gives you four patterns of four holes, and four patterns of three holes, with one set of holes being common.

Knowing the spacing, you can layout a workpiece to those dimensions and drill the mounting holes, and it should mount. If you work in metric, make the machined circles spaced in whole centimeter divisions.

You won't necessarily have to drill and tap all the holes to start with, but having them laid out and pilot holed would be good. You can always tap the ones you need as you need them.

That would be my suggestion anyway-

Paul Alciatore
12-13-2010, 12:39 AM
Unless you have some specific job that requires a particular hole pattern, you might consider radial slots instead of holes. Three or four of them. Use tee nuts or tee bolts to fasten things to it. That way you don't have to worry about the spacing. Also, lathe dogs of many different sizes and designs will also work with them. Slots are probably much more common on face plates.

randyc
12-13-2010, 01:02 AM
Darryl's advice is always good.

Forrest Addy
12-13-2010, 01:24 AM
I suggest you make a half dozen faceplates (they always come in handy) and leave them undrilled. Maybe T slot one. You never know what holes to drill or where to put them. Wait for the job then put the holes where you need them.

BillTodd
12-13-2010, 07:05 AM
If you're very careful, it's possible to space the hole too close for half the jobs you want to mount, and too far apart for the other half ;)

Bill

Rosco-P
12-13-2010, 09:09 AM
Forrest has it correct. You're trying to make a universal work holding device for a job that doesn't exist yet. Make a faceplate and give it four slots, leave a second (and or third) one blank. Faceplates end up like swiss cheese eventually after several jobs. No need to give it a head start. Parts mounted to a faceplate are often oddly or irregularly shaped or need to be machined off-center. Otherwise, you'd grip them in the four jaw chuck. I fail to see how marking the faceplate off with concentric circles, gives you any sort of leg-up.
Same logic hold true for holding work to angle plates. The plates with factory slots rarely have the slots where you need them. Better to buy (or make) solid angle plates and drill them as necessary.

krutch
12-14-2010, 03:40 PM
I made a face plate for my HAAS 5C indexer and it is much larger than your app. I have five radial slots which have served well so far. I also made special nuts and recesses for 3/8 hold down studs and clamps.
In your case the advise of multi plates and 'drill as you need holes' might be the answer. I've seen shop made plates that looked like swiss cheese after many different uses. And they still get used.

rohart
12-14-2010, 05:07 PM
I'd go with Paul and Forrest, but make two slotted plates. One with 45 degree spacing, and the other with 60 degree spacing. It gets a bit busy if you combine them, but if you do it bit by bit as you need it, it's OK.

I just mount a plate like that in my 3-jaw and use it as is. Sure, I could do with a full sized faceplate, but I haven't got round to making it yet.

My mistake was to make the plate thinner than the outer part of my chuck jaws, so if anything has to overlap the edge of the plate where the jaw is I have to shim the plate out.

Ian B
12-14-2010, 05:16 PM
3.30"diameter? Forget any pre-tapped holes, slots etc. As said before, just make blanks, drill and tap as the need arises. That's a really small diameter to be thinking of studs and clamps - hell, I struggle with a 10" rotary table!

Good luck,

Ian

oldtiffie
12-14-2010, 05:17 PM
I'm making a 3.30" dia faceplate for my Sherline lathe, and am curious what you think the tapped hole spacing should be. Is there a certain pattern I should follow that works well for most everything? Or should I just tap as I go when needed?

That's a small face-plate and there won't be much room for slots and there won't be much room for clamping bolts over 1/4" either - and the job - and clamp packing/spacers.

Paul Alciatore
12-14-2010, 11:21 PM
3.30"diameter? Forget any pre-tapped holes, slots etc. As said before, just make blanks, drill and tap as the need arises. That's a really small diameter to be thinking of studs and clamps - hell, I struggle with a 10" rotary table!

Good luck,

Ian

With such a small faceplate you would not use 1/2" (12mm) or even 3/8" (8mm) sized studs as many of us are used to thinking about. Quarter inch (6mm) would be the largest you would want to consider and a #10 screw size (4 or 5mm) would be a good choice and even smaller ones would be useful for some jobs. At those sizes, you could get a goodly number of holes or slots on it. My Unimat faceplate is in that size range and it has slots sized for 6mm hardware.

Sportandmiah
12-14-2010, 11:44 PM
3.30"diameter? Forget any pre-tapped holes, slots etc. As said before, just make blanks, drill and tap as the need arises. That's a really small diameter to be thinking of studs and clamps - hell, I struggle with a 10" rotary table!

Good luck,

Ian

Remember that this is a Sherline lathe, with a 3.5" swing over bed. A 3.3" dia faceplate is about all that can fit, unless I add risers. That being said, I like the idea of making a handful of them and tapping them as the project arises.

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