Making a steady rest

[Bill Gruby]

Looking good Darren. I like the mods you made. Mine is still going strong.

"Billy G"

[Mayhem]

I postponed another job I had to do today and decided to see if I could make an attachment for my lathe that would allow me to fasten the steady rest to the saddle, so that I could hold the 31mm drill in my chuck to make the holes for the telescoping rollers.

I used some 5/8 UNC all thread to make up a couple of T-bolts to make use of the t-slots and used some 1/2" BSW bolts to match the threaded holes already in the cross slide. Welded some rectangular tube section on to give a level frame onto which a piece of particle board was fastened.

I had turned a section to match the internal diameter of the steady rest and this was lined up so that the centre line ran between the centre I had in the chuck and the one on my tail stock. I even chucked up a length of ground stock to check.

The pics tell the story:

   
   
   
   
   

All was going well until I removed it to test fit one of the assemblies and I noticed this
   

It took a moment to realize where I screwed up. I had placed shims under the frame to get it at the right hight but when I clamped it down, it settled a bit, so the hole would have not been in the centre of the three plates. Because the frame is a tight fit on the particle board, I used a screw drive to pry it up to remove the shims and install thicker ones. I must have rotated it slightly whilst doing this, as I don't recall checking the alignment again

I'll turn a slug and weld it into place and try again. The positive thing is that I know I can drill the hole this way. All I need to do is double check the positioning before drilling.

[TomG]

I've run into that before as well Darren, it doesn't take much to compress plywood. Now I use hardboard or MDF whenever I clamp something to the mill table, which has a much higher compression strength. That's a very creative set-up, it looks like it will work fine once the details are worked out.

Tom

[PixMan]

It's a steady rest, not a high precision measuring instrument.

The top one being a little out of whack is no big deal, as it doesn't carry any load except under a very heavy cut on lighter work pieces.

How do you plan to fasten the telescopic assemblies to the frame anyhow? I know the OD of the pipes is a somewhat out-of-round 1-1/8", not 32mm so there should be enough room to get it a little straighter.

[Mayhem]

I know it is a steady rest but it is an eyesore the way it is!

The 32mm hole is for ease of mounting. I plan on making up some sleeves, with a small flange. I will drill the sleeves in 6 places along the length (top and bottom, 120° apart) to spot weld them to the outer tubes on the roller assemblies. This will (should) eliminate distortion and any weld sitting proud can be turned down. All this will be hidden inside the frame.

Once in place the flanges will get welded to the frame and I can also drill a hole through the frame and spot weld back and front.

[Mayhem]

OK - I managed to squeeze in some shop time today and I got a plug turned and welded in to the wonky hole. I also managed to get three sleeves turned up and one of them spot welded onto the external tube for the roller assembly.

All holes drilled and true to the centre line:

   

One of the sleeves spot welded to the tube. I did it this way as it will not distort the tube like a seam weld could. Also, each sleeve is a nice tight fit into the hole in the frame:

   

A mock up (I forgot one of the tubes). The top tube isn't fully in position, as the sleeve is a tight fit and needs a little persuasion:

   

Oops! Consider this my version of an out-take
   

Now all I need to do is get the other tubes welded up and all three welded into the frame. Once that is done, I will drill and tap the holes for the screws that will stop the bearing carriers from spinning.

Oh - and I have to make the pins for the bearings. I found some 12mm rod from an old printer that will do nicely. The paint and a test drive

[PixMan]

I don't know if you've spent much time thinking about the final position of the tubes and how that relates to where the bearing supports will be extended to for the bulk of the applications.

The whole assembly may be capable of accepting 300 mm or more in size, but I wouldn't be putting too much weight on 10mm wide standard duty bearings. If you were to push the tubes in a little more and limit diameter to 200 or 250mm, the bearing carriers would have better support for the more common applications of long, small-diameter work.

Just thinking, probably too much.

[Mayhem]

So having about 50mm stick out on the inside would be the way to go? Good job I have only welded one sleeve onto a tube!

[Mayhem]

Managed to get a little shop time yesterday and turned the three sleeves. I then welded two sleeves to their respective tubes and pushed these into the frame.

   

I then mocked it up in position. Note that I am waiting on a replacement tube, which is somewhere between Spencer, MA and my house as we speak!

   

I will weld the tubes into position once I have all the pieces together, so that I can check alignment etc. Shouldn't be long now

[EdK]

It's getting there Darren. Can we expect a video once it's done?

Ed