looking large faceplates for bowl turning!

I posted an answer over in r.woodworking. Be ware most people won't see your post because you're using a gmail email address. Google gmail is the source of most of the spam found on newgroups, so most people filter and automatically discard gmail posts.

How big of a bowl?

Bill Noble makes and sells face plates..

Keep in mind that the foot of a bowl is usually much smaller in diameter than the lip/top...

On the occasions that I use faceplates for bowls, I turn 14 to 16" bowls with the 6" faceplate that my lathe came with..

I usually start them between centers and turn a tenon for the lathe chuck..

mac

Please remove [dot]splinters before emailing

Oneway makes an 8 inch ($115) and a 10 inch ($155). They are made out of cast iron. Very heavy. You would have to be turning some pretty big pieces to need a face plate that big. My lathe has a 24 inch swing and I have never needed a face plate bigger than 6 inches.

This is the URL to Oneways face plates:

Ted

I've made a few large diameter faceplates - but the biggest I can turn on my metal lathe is 12 inches - actually, it's pretty ungainly at much over 8 inches because I have to be careful the carriage doesn't hit the work, but it's possible. I can certainly do it for less than one-way prices, but seriously, how big are you talking about - I can swing 44 inches on my wood lathe and I use a 4 inch faceplate (usually) - to start between centers -

you can find me at

If what you want is to follow John Jordan's advice and get the screw holes outside of the base so you turn them off when you are finishing the base, then you can screw a piece of plywood to a smaller faceplate.

The key is that steel is a lot stronger than wood - if you are turning more than 80 or 90 pounds, then larger than 4 inch faceplates are good - the largest I have for my wood lathe is 6 inches - but I've found that the lag bolts usually shear off if I'm getting a lot of shock loading (such as when working on a serously out of round piece). If you are going to be turning stuff in the 500 pound and up range, I'd suggest using faceplates designed for metal lathes - and I'd suggest that you really don't want a spindle much under 2 1/4 inch - minimum.

So, can you provide more tetails of what you are trying to do?

** Posted from **

Good info, Bill. Especially the reminder about placing the lags outside the finished base. I had forgotten about using John's dodge and some of his other good ones.

Re shearing the fixing screws or lags, I do remember that a roughened face plate instead of a mirror finish probably helps to secure the drive and take some stress off the screws. Does fixing the screws at a wide diameter on a large faceplate tend to shear them more easily than at a narrow diameter on a small faceplate?

I imagine the support of the tailstock relieves a lot of stress on the drive and should be used as much as possible. I wonder if supporting the tail end of a heavy unbalanced blank at a point (60 deg, tail center) stresses the tail spindle more than a larger diameter support. Maybe we should consider a small revolving face plate on the tail spindle until things get round and balanced?

I suppose that ramping or clutching the rpm when starting or stopping a heavy unbalanced blank is also important re the stresses imposed on the faceplate and its screws.

One advantage of a large diameter and necessarily more robust faceplate might be the additional space for attaching balancing weights and dogs.

Turn to Safety, Arch Fortiter

If the problem is one of handling seriously out of round blanks, why not clamp a router or body grinder to the tool rest and remove the offending protrusions with the router, etc. running and simply hand feeding the blank to the cutting tool?

Pete Stanaitis

-------------

Some famous turner I saw uses an Excaliber (?) or similarly named device to start his off. It is a circular chainsaw blade that fits on a 4" grinder and is used for carving.

Same idea.

Robert

lag bolts are strong - I have two holding a piece of iron to a 4X4 that I use for pulling engines - I know that they are strong enough to hold the full weight of a 1/2 ton pickup truck because I accidentally lifted one (by not unbolting the last bolt holding the engine in place). That said, the soft steel they are made of will shear by impact with the faceplate - in fact in roughing a large piece where I don't realy want to round it off, I can shear 3 of four lag bolts in a few minutes if I try (and of couse that is just stuipid but it can happen). The cause is the shock load transferring to impact against the side of the lag. Using tailstock support is absolutely necessary or the heavy object will leave the lathe and that is not a good thing.

stress on the spindle - doesn't matter what the tailstock is - but it better be pointy or the object being turned will move around and that doesn't bode well for what happens next.

Any lathe that can turn a large object will ramp up - mine has variable speed and a preset ramp up curve - that is not where the problem comes from.

Balancing is good, but I don't do it - beacuse as you shape the natural edged gnarly object, the balance changes quickly - I do occasionally use a chain saw, but usually not because I want to shape it and look at what is happening.

** Posted from **