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Cannonmn
11-07-2016, 06:34 PM
A new-to-me 14" Leblond faceplate installed on the 19" Leblond lathe has 0.003 runout on the outer rim, which is fine with me. But the face itself has 0.017 runout in the axis parallel to the ways, way too much. Do I take facing cuts on the front of it as if I were cutting in a Chuck backplate, or do lathe operators just live with faceplate runout?

Magicniner
11-07-2016, 06:37 PM
I face them, otherwise you need to compensate for any run-out in your set up for any part with a reference face against the plate,

- Nick

Stepside
11-07-2016, 06:55 PM
1) remove and check for burrs and/or dirt on both the faceplate and the register on the lathe.

2) If okay in step one, then face. If step one shows problems, take care of them first.

3) If a non-threaded mount, mark so you always use the same pin holes in lathe and plate that you used to face the plate.

Forrest Addy
11-07-2016, 09:09 PM
1) remove and check for burrs and/or dirt on both the faceplate and the register on the lathe.

2) If okay in step one, then face. If step one shows problems, take care of them first.

3) If a non-threaded mount, mark so you always use the same pin holes in lathe and plate that you used to face the plate.

Yup! Absoultely as above!

Paul Alciatore
11-07-2016, 11:36 PM
Absolutely check it first. 0.017" runout sounds like a lot to me. Also check to see that it seats properly on the lathe. The internal thread could be cut short.




1) remove and check for burrs and/or dirt on both the faceplate and the register on the lathe.

2) If okay in step one, then face. If step one shows problems, take care of them first.

3) If a non-threaded mount, mark so you always use the same pin holes in lathe and plate that you used to face the plate.

old mart
11-08-2016, 08:07 AM
posted in error

boslab
11-08-2016, 10:10 AM
When I got my Harrison lathe the 12" screw on faceplate had been faced so many times the boss was proud of the face, still is!, I need to get another or bung a plate on it, I've often wondered why faceplates don't have a sacrificial face that can be replaced, it's on my list
Machines in work like DSGs faceplates usually went on really close, bar one with a slack thread/register, thein lay the explanation, slack and wobbly.
All it takes is a chip or bit of dirt to throw the thing off, as has been said, any tiny error at the centre gets magnified like an optical lever.
Mark

pinstripe
11-08-2016, 10:49 AM
Your faceplate probably belonged to the guy I saw on a video that said he faces it every time he uses it. Can't remember who it was. It would last hundreds of uses if the cut is light, but it still seems wasteful to me.

Rich Carlstedt
11-08-2016, 12:10 PM
When our faceplates at work got "thin" , we mounted a 1" disk of Aluminum on them which renews the faceplate and allows for custom holes and slots.
+1 for Stepsides comments

Rich

Cannonmn
11-08-2016, 12:19 PM
Your faceplate probably belonged to the guy I saw on a video that said he faces it every time he uses it. Can't remember who it was. It would last hundreds of uses if the cut is light, but it still seems wasteful to me.

I think I know that guy too! He likes to do everything 200%. Like the time he had to turn down some hex steel bars on one end. He already had 3-jaw chucks but paid over $1K for a six-jaw because he felt using only 3 jaws for hex stock would be cutting corners.

boslab
11-08-2016, 01:21 PM
I think I just wet myself, cutting corners!, I like the Ali plate idea, I can see that happening
Mark

softtail
11-08-2016, 01:27 PM
Remember the outer end of the plate will be really be spinning compared to the center when considering rpms..

huntinguy
11-08-2016, 02:10 PM
When our faceplates at work got "thin" , we mounted a 1" disk of Aluminum on them which renews the faceplate and allows for custom holes and slots.
+1 for Stepsides comments

Rich

We put the aluminum plate on the new faceplate. After it was lightly skimmed to clean up. That preserved the original face surface in case we really needed it.

Dave C
11-08-2016, 04:04 PM
Remember the outer end of the plate will be really be spinning compared to the center when considering rpms..

Wrong! Surface speed increases with diameter but RPM is the same as spindle speed regardless of diameter.

Joel
11-08-2016, 04:26 PM
He said "when considering RPM's" - as in, for selecting the appropriate spindle speed.

Cannonmn
11-08-2016, 06:15 PM
Ok while we're on the topic of faceplates, here's my experimental "4-jaw faceplate" setup using four serrated-bottom, articulated toe clamps. I wanted to take 1/2 inch face off this thick steel plate. I could have put it in a Chuck with enough sticking out to face that much off, but the faceplate was mounted already so I thought I'd try it this way-probably won't exceed 75 Rpm. I don't think this way has as much clamping force as a Chuck, but is there another faceplate setup I should use next time? I could have used only 3 clamps, or used articulated clamps at 12 and 3, then plain clamps at 6 and 9 o'clock.https://springfieldarsenal.files.wordpress.com/2016/11/img_4136.jpg

Cannonmn
11-09-2016, 05:07 PM
We tried the toe clamp method by facing the plate. It didn't go well, the plate didn't fall off but the front ends of the clamps loosened during turning, messing up the cut and forcing us to quit.

We removed the faceplate and made sure it and the spindle nose were clean, burr-less, etc. We re-mounted it and tightened the nut as much as was with the 30" spanner as before. But this time we took the additional step of beating on the faceplate with deadblow hammer in various places while leaning on the spanner in the tighten direction. Each tap in certain areas let the handle end of the spanner move about 1/2 inch "tighter" until it had gone about 6 more inches than the last install. That reduced runout from 0.017 to 0.010. We then took a light facing cut which reduced runout to under a half-thousandth.

Here's pic after the facing cut

https://springfieldarsenal.files.wordpress.com/2016/11/img_4146.jpg

BCRider
11-09-2016, 06:30 PM
The proof of the pudding is how consistently it can be replaced. Try removing it and seat it again.

I'm also a bit puzzled on why it won't achieve a good seating without the dead blow treatment. From the picture in this last post it looks like it's the style which is a long taper with a key. Unless the key itself is a really snug fit in your plate I don't see why you should need to rain dead blow swings against it to seat easily. If the key way is that snug then perhaps a touch of judicious filing on the shiny high spots or even open up the keyway a hair to ease the seating? A taper nose fit like this should be pretty easy to position accurately without resorting to that sort of force.

Or did I not spot the style of nose correctly and it's some other style?

Cannonmn
11-09-2016, 07:50 PM
Thanks for the info. Yes it is an L1 spindle nose. Don't know why it needed blows either, must be some slight irregularity we couldn't see or feel. We'll keep looking for a cause every time we mount it. If we don't find something fixable we'll just use the same procedure then check runout every time, as whole procedure only takes a few min. If that's all it takes to get essentially zero runout I'm happy to do it.

Edit: Next time I mount it I'll degrease both mating areas and put indicator fluid on one so I can see any points of interference when I remove faceplate.