Lathe Spider

[thehomeengineer]

Hi All
I have finally got around to making a lathe spider, rather than using rags or pieces of wood jammed into the back of the headstock spindle to stop long pieces of material flailing around.

I wanted it to be quick and easy to install and remove. So based the locking method on my lathe spindle backstop. Link to backstop:Quick to load and set lathe spindle back stop.

Both the main body and the locking wedge are made from mild steel off cuts held with a M6 countersunk screw loctite in position. To jack the wedge a M6 grub screw is used. To ensure a good slide fit in the spindle, both pieces are machined together.
The spider is fitted with 4 standard M8 brass screws turned down to 45 degrees at the end to enable small diameters to be supported.

I wish I had made one years ago but it is one of those jobs that you will one day get around to. But now I have it there is no more making do with rags and wood etc that you never know if they are going to stay in place.

The following photos show some of the spider being made and in the headstock spindle:

both body and wedge being machined together.


machined to diameter


Taken apart to clarify design.


Grub screw used to expand wedge.


Finished ready to install.


Fitted to head stock spindle


Supporting 1/4 diameter aluminium tube


I hope this will be of interest and thank you for viewing

The Home Engineer

[mklotz]

Nice job, indeed. I particularly like the wedge design. I'm going to add that one to my 'appropriated ideas' file.

And, of course, you realize that you've now made yourself a chuck depth stop. A simple rod will suffice but you can titivate it by drilling and threading the chuck end of the rod so that smaller diameter inserts can be used when the work diameter is less than the rod diameter. (If I were doing it I'd make the rod about 3/8" diameter.)

[Christophe Mineau]

Yes, same as Marv, this locking system is a great idea. It will go straight to the to do list !
Thanks for the sharing.

[DIYer]

Thanks thehomeengineer! We've added your Lathe Spider to our Lathe Accessories category,
as well as to your builder page: thehomeengineer's Homemade Tools. Your receipt:

Lathe Spider by thehomeengineer

tags: lathe, spider

[desbromilow]

great idea, and the wedge system is quite clever. I can see a few other applications of this with only a few minor modifications (eg slip fitted plug held in place with the same brass screws - said plug supporting a chuck/ stock back stop), holding a magnet for tacho, etc

[Toolmaker51]

Nice job, indeed. I particularly like the wedge design. I'm going to add that one to my 'appropriated ideas' file.

And, of course, you realize that you've now made yourself a chuck depth stop. A simple rod will suffice but you can titivate it by drilling and threading the chuck end of the rod so that smaller diameter inserts can be used when the work diameter is less than the rod diameter. (If I were doing it I'd make the rod about 3/8" diameter.)

A 3/8" rod is a great start, will accommodate many material shapes. Depending on headstock length and RPM range, most diameters will go harmonic and whip inside the spindle tube. The best cure is a nylon or aluminum bushing to maintain central position.
My preferred stock for a stop rod or ejector is light weight tubing, with bushing. Accepts 'tooling' just as easily,to compensate different forms of turned work pieces.

I rarely edit my posts.......(more than once a day). Warranted in this occasion about stop rod tooling.

Whatever material selected, find a lightweight long compression spring of diameter suitable for a nice sliding (non-binding) fit. With any kind of setscrew collar as a seat, it will eject parts from chuck or collet by varying the compression, a little nudge or completely out.
It also adds tactile sense when contacting the rod, upon loading the next part.

[mklotz]

A 3/8" rod is a great start, will accommodate many material shapes. Depending on headstock length and RPM range, most diameters will go harmonic and whip inside the spindle tube. The best cure is a nylon or aluminum bushing to maintain central position.
My preferred stock for a stop rod or ejector is light weight tubing, with bushing. Accepts 'tooling' just as easily,to compensate different forms of turned work pieces.

Welcome back; long time no see.

The bushing is a good idea. Given its job, it could even be made of wood. Yes, wood has its place around a metal lathe.

When I was making an ejector rod to knock centers out of the spindle, I considered using a tube but didn't have anything suitable at the time. So I used a length of wooden closet rod with diameter about a sixteenth less than the spindle ID. Fitted with an aluminum 'cushion' on the business end and a chunk of metal waste for mass on the outboard end, it worked a treat, in fact well enough that it still hangs behind the lathe waiting to work again.

[Toolmaker51]

Welcome back; long time no see.

The bushing is a good idea. Given its job, it could even be made of wood. Yes, wood has its place around a metal lathe.

When I was making an ejector rod to knock centers out of the spindle, I considered using a tube but didn't have anything suitable at the time. So I used a length of wooden closet rod with diameter about a sixteenth less than the spindle ID. Fitted with an aluminum 'cushion' on the business end and a chunk of metal waste for mass on the outboard end, it worked a treat, in fact well enough that it still hangs behind the lathe waiting to work again.

A knock-out is the first tool one needs for knocking out centers, or their more difficult brothers, collet adapters. Mass is king, a hand propelled pop is plenty, other catches the item, instead of tying up both with a hammer. Closet rod is good, my first was the stick from a corn broom.

Agreed, wood is fine for a support bushing. If sealed with any non-petroleum oil will last figuratively for ever. I use olive or corn oil for all kinds of metal to wood connections, especially screws.
The usual recommendation is bar soap - tedious to apply on a handful of fasteners, ie attaching door hinges.
Most recent, refastening deck screws inside my box truck. I backed out those protruding above, a spot of lube and back in they went, bottomed out. First and second, tried dry, squeaked and snapped off. Remaining 20+; no problem. Those are self-drilling and tapping hardened flat head square drive 1/4-20, frame rail is about .200 thick, off course the originals (c 1999) had some rust.
When I'm pushing cardboard boxes, they should slide; not snag box or tape on proud screw heads.

Regarding absence; others noticed too, including a protege and 'my' unrelated auctioneer/ reseller. I've been preoccupied, tired of being a widower. No announcements as yet, just progress. . . I greatly appreciate the welcome by Mr. K.