Are chuck spindle adaptors "safe" to use?

[Mark Ahlenius]

Hi,

I just got a new (used) lathe which has a 1-1/4" 8 TPI spindle. My old Delta lathe had a 1" 8 TPI spindle and I have a Super Nova chuck for that. Wondering how safe it is to use the spindle adaptors (~$20) to go from the female 1-1/4" spindle on my new lathe to the Nova chuck which has the 1" female thread? My concern is a bit more about wobble and safety as you are hanging out a large and somewhat heavy chuck on longer spindle. Does using one affect the accuracy of the chuck by possibly introducing any vibrations (via wobble)?

thoughts?

thank you

'mark

 

[robo hippy]

I would check to see if the female insert is removable before getting an adapter. I do believe most chucks are that way. There are some that are drilled exactly for one size and can't be adapted/changed out. You are correct about the adapters adding to any wobble there already is on your lathe and chuck.

robo hippy

 

[Tom Gall]

For most/majority of turnings this should not be a problem. Most adapters only add about 2" from the headstock and they are pretty stout. I went through that problem several decades ago, and still use the adapter occasionally for some chucking situations.

 

[John K Jordan]

My concern is a bit more about wobble and safety as you are hanging out a large and somewhat heavy chuck on longer spindle.

I've seen several spindle adapters and some looked better than others. I recently bought one from Best Wood Tools and it is extremely well machined. I bought the 1-1/4 to 1-1/4" version (basically and extender) but I'm assuming his others are also well made. With the smaller thread, I might be a bit more more cautious with heavy and unbalanced blanks but for most things I think the adapter should be OK.

But as Sir Robo noted, is your chuck direct-threaded for 1"x8 or does it have a removable insert? All my chucks are Novas and I use the removable inserts on each (except for one direct-threaded Titan). When I gave a couple of G3 chucks to a friend with a smaller lathe, I simply unscrewed the inserts and put in new inserts to fit her lathe. (My apologies if you are already aware of that!)

JKJ

 

[Roger Wiegand]

Seems it's more typical than not for chucks to use adapters. It's only been very recently that you could get a Vicmarc direct threaded, for example. If the inserts are creating wobble I can't detect it.

 

[hockenbery]

My concern is a bit more about wobble and safety as you are hanging out a large and somewhat heavy chuck on longer spindle. Does using one affect the accuracy of the chuck by possibly introducing any vibrations

Like @Tom Gall - Unless it is a poorly made adapter it should work well for most things.
It will introduce more vibration - but probably so small you can’t notice it.

If your chuck has an insert, the better solution would be getting a 1 1/4 insert. Then you don’t have to use an adapter.
Insert probably costs less than a quality adapter.

I often demo using chuck threaded m3.5 x 33 on lathes with 1” or 1 1/4” threads using an adapter.
Never had a problem and some club lathes are less than great.

 

[Walter Mooney]

Hi,

I just got a new (used) lathe which has a 1-1/4" 8 TPI spindle. My old Delta lathe had a 1" 8 TPI spindle and I have a Super Nova chuck for that. Wondering how safe it is to use the spindle adaptors (~$20) to go from the female 1-1/4" spindle on my new lathe to the Nova chuck which has the 1" female thread? My concern is a bit more about wobble and safety as you are hanging out a large and somewhat heavy chuck on longer spindle. Does using one affect the accuracy of the chuck by possibly introducing any vibrations (via wobble)?

thoughts?

thank you

'mark

+1 for what JKJ said — Best Wood Tools adapter. I have one and use it all the time, no issues!

 

[Michael Brown]

Like every one else, I got a 1-1/4f to 1m adapter and it was fine. 2" bar milled down with 1/2" solid between the two threads. I did end up boring a 3/8" hole perpendicular to the shaft to use a breaker bar in leu of a 1 7/8 flat wrench... As it quickly started rounding over when I used a crescent wrench when I was done.

 

[Mark Ahlenius]

I would check to see if the female insert is removable before getting an adapter. I do believe most chucks are that way. There are some that are drilled exactly for one size and can't be adapted/changed out. You are correct about the adapters adding to any wobble there already is on your lathe and chuck.

robo hippy

Hi Robo,

thanks for you reply. You were correct, all 3 of the Nova chucks that I currently own have the insert in them which was removable. I found inserts at our local Woodcraft made by Nova which go from the chuck internal threaded opening to 1-1/4" with 8 TPI. I purchased the one they had in stock and ordered 2 more so I can keep them locked in each chuck.

Appreciate your posting on this.

'mark

 

[Mark Ahlenius]

I've seen several spindle adapters and some looked better than others. I recently bought one from Best Wood Tools and it is extremely well machined. I bought the 1-1/4 to 1-1/4" version (basically and extender) but I'm assuming his others are also well made. With the smaller thread, I might be a bit more more cautious with heavy and unbalanced blanks but for most things I think the adapter should be OK.

But as Sir Robo noted, is your chuck direct-threaded for 1"x8 or does it have a removable insert? All my chucks are Novas and I use the removable inserts on each (except for one direct-threaded Titan). When I gave a couple of G3 chucks to a friend with a smaller lathe, I simply unscrewed the inserts and put in new inserts to fit her lathe. (My apologies if you are already aware of that!)

JKJ

Yes sir, please see my response to Robo. It turns out they do.

thanks for your rely

 

[William Moschler]

Now be sure the chuck's run true with the new adaptors I got a bad adaptor from Woodcraft when I bought my first Nova chuck. And..a direct thread for the 1 1/4 spindle Supernova 2 chuck body is about $110 from Acme and will take all your current jaws.

I also use a spindle adaptor for a couple of specialty chucks and think they are safe if installed correctly.

 

[John K Jordan]

Now be sure the chuck's run true with the new adaptors I got a bad adaptor from Woodcraft when I bought my first Nova chuck. ...

I also use a spindle adaptor for a couple of specialty chucks and think they are safe if installed correctly.

There were reports from others (about 10 years ago or so) of Nova inserts from Woodcraft that did not run true. One would think they have any problem worked out by now.

In case there is confusion whether "adapter" as used here is a spindle extension adapter that started this conversation, or if it is referring to the chuck insert that adapts the Nova chuck to a specific lathe thread, there are some things that can be checked

Before installing any type of "adapter", I make sure the threads and seat on both the chuck and adapter, and lathe spindle are clean and free of any burrs or debris. I keep a dial indicator on an adjustable magnetic base (inexpensive these days) and sometimes use it to check if chucks run true. If something is off, remove things, examine and clean again, then remount and see if it helps.

While on the subject, dial indicators can also be good when rechucking a piece and for aligning other things for for turning. In this picture, I had glued two 3-corner pieces together (turned with the clever cube method) and am holding them under pressure against what might be called "soft" jam chucks so to touch up the joined area a bit.



For both wood and metal working, I especially like this adjustable arm style. The knockoffs of the original highly prized Noga design are inexpensive now, and acceptable dial indicators are as well. Search Amazon something like 'magnetic base with dial indicator'.

If not familiar with dial indicators, be sure not to accidentally order a "dial TEST indicator", entirely different, more precise, less range, useful for precision alignment on the milling machine but not nearly as useful for wood turning as a dial indicator (IMO).

JKJ

 

[Bill Alston]

There are plenty of direct threaded chucks available over here. I wouldn’t have anything else after buying a chuck with a threaded insert that had poor runout. Separate adapters are a big no for me. Probably ok if there’s little to no runout and you’re not hanging a large blank on it though.