My New 8x18

Glad to hear things went well.

Yes, when you start a cut in the middle of a shaft, it does not dig-in right away and will gradually get deeper as the cut progresses. Normally for a simple cut, I start at the very end of the shaft by the TS so the bit digs in right away upon hitting the material. If you must start in the middle, it's common practice to use a groover and dig a starting point.

Were you using carbide or HSS-type cutting bits?

Watch out for swarf... overcome the urge to touch it or get near it when the machine is in motion -and that means wait till a dead stop. Many cut tendons (and worse) from machines smaller than yours.

Ray



wrmiller19 said:
OK, so just as a quick-and-dirty, I tried a couple of cuts yesterday.

The first, was on a .5" piece of stainless. Put in in the three-jaw, center-drilled the end and put that on a live center. I took a .015" cut for almost 5". I started about 2" from the live center. I noticed that near the live center, I was getting small(er) chips, and as I got within a couple of inches of the 3-jaw I started getting this long, golden colored chip that had the cutting fluid smoking a bit. Pulled the rod out and did a quick measurement with my calipers. There was just over a thou difference between the measurements (I measured about 3" from the live center end, and right near the chuck). Not bad at all. I figured from watching the chips that I was getting some part deflection.

Next was a piece of 6061, 5/8ths thick. Did a .025" cut for about 3" on the unsupported rod. Bright shiny cut that had this long chip wrap itself around the rod near the chuck. Have to watch that stuff, as I figure it can probably slice me up pretty good if I'm stupid enough to get my hands near it. After pulling the aluminum Brillo pad off the part, I pulled the rod out and measured it like I did the other. Less than a thou difference.

Good enough for now. I'm pretty happy so far.
Click to expand...
 
Ray C said:
Glad to hear things went well.

Yes, when you start a cut in the middle of a shaft, it does not dig-in right away and will gradually get deeper as the cut progresses. Normally for a simple cut, I start at the very end of the shaft by the TS so the bit digs in right away upon hitting the material. If you must start in the middle, it's common practice to use a groover and dig a starting point.

Were you using carbide or HSS-type cutting bits?

Watch out for swarf... overcome the urge to touch it or get near it when the machine is in motion -and that means wait till a dead stop. Many cut tendons (and worse) from machines smaller than yours.

Ray
Click to expand...

Ah...thanks for the tip on the groover. I'm no machinist, I just like playing with their machines. :)

The only lathe tooling I have is a little 3/8 set with indexable carbide inserts. They didn't work too well on the smaller lathe, but seem to do much better on this one. 1.5hp and better rigidity probably make a difference. When I get some 1/2" tooling I will try larger cuts. My little 0XA tool post is getting replaced with a AXA I ordered today. I don't like having the tool holder all the way at the top of the tool post.

I found my Inspection Report, and here's how my lathe tested out:

Geometrical Accuracy

Longitudinal Straightness of Bed: 0.03mm/500mm
Spindle Center Runout: 0.01mm
Spindle Shoulder Runout: 0.03mm
Spindle Bore Runout: 0.01mm
Spindle Taper Runout at Spindle Face: 0.01mm
Spindle Taper Runout at 100mm from Spindle Face: 0.02mm
Transverse Parallelism Between Spindle Centerline & Carriage Movement: 0.02mm/100mm (Only Up)
Longitudinal Parallelism Between Spindle Centerline & Carriage Movement: 0.02mm/100mm (Only Forward)
Transverse Parallelism Between Tailstock Centerline & Carriage Movement: 0.02mm/100mm (Only Up)
Longitudinal Parallelism Between Tailstock Centerline & Carriage Movement: 0.02mm/100mm (Only Forward)
Difference Between Spindle & Tailstock Centerlines: 0.03mm (Only High at Tailstock)
Perpendicularity of Cross Slide & Carriage Movement: 0.04mm/100mm (a > 90 degrees)
Longitudinal Straightness of Carriage Movement: 0.03mm/500mm
Axial Slip of Leadscrew: 0.01mm

Operational Accuracy

Accuracy of Outside Turning: 0.02mm
Accuracy of Cylindrical Turning: 0.04mm

I understand some of these, some I don't. All measurements were within recommended standards.

If these measurements are real, and based on my initial experiments, should I bother with the tailstock? Other than turning a long piece between centers, The only method I know is to put the dead centers in both the spindle and tailstock and pinch a small piece of flat steel in between and look for a vertical orientation of the piece of steel?

Bill
P.S. Maybe someone who is REAL bored can explain those measurements?
 
If you are that close you are good to go my friend. Those are not bad for an out of the crate machine.

"Billy G"
 
Some thoughts...

An AXA on your machine will be ideal and most likely, 3/8" tool holders will serve 99.999% of your needs. Of course, it's up to you but when you get 1/2" tooling, you might need to get multiple sizes of the same style inserts -and after a while, you might get annoyed with the extra cost and keeping track of them. Also, 3/8" tooling is more than capable of pushing your lathe to it's limits. The only time you might really need 1/2" holders if you need to make a cut that's difficult to reach and you need to extend the bit pretty far. The beefiness of the 1/2" will allow further extension.

Tailstock use: Just about any time you have a shaft where the length exceeds (roughly) 3 times the diameter, you should use a live or dead center in the TS. This of course is a guideline and some folks will say 2 times and others say 4 times... The point is, unsupported shafts bend due to the cutting pressure -especially with carbide and the diameter will end-up greater at the unsupported end because the work piece gets pushed away from the bit. As the cut gets closer to the chuck, the piece is unable to bend as much and the bit digs in deeper. Your pieces will end-up as tapers. Also, supporting at the TS will put an end to any kind of vibration or chatter which will happen almost certainly on anything longer that 4-5 times the diameter.

Im not sure what you mean in the last sentence about pinching a piece of flat steel. I might need to see a picture of what you're doing there...

A few words about alignment and your specs.... Many of those specs might not be valid until you align the machine. Also, I don't know if those specs were produced when the machine was mounted on a perfectly flat table or not. In any event, once a machine is lifted, crated and jostled across a couple continents, some of those specs might not be valid until you adjust your bench for alignment.

Please look-up and search this site for "2 collar method" and "Rollie Method". Those two techniques will describe what's going on. It might take a while to comprehend the concepts so, please read it until you feel you understand it before tweaking your machine and bench. You can always ask questions here. Like Bill G said, you're good to go and there's no real harm done in using the machine as-is and learning to do basic things before you get into alignment. Other folks might disagree and would advise to align first so, please don't think I'm a quack... Everyone has their preferred methods and it all comes out in the wash at the end of the day. It's all good. BTW: I'd really recommend sticking to mild steel or aluminum until you get the swing of things. Stainless is one of the trickier metals to work with. It's tough as nails and fights back. It's not a hard material at all -just very tough. It wears-out carbide in no time flat if you do things wrong. -Beware, SS swarf comes off hot and sharp as a razor...

I do believe I understand and comprehend most of the specs but there are other folks here more qualified to speak about it. Only in the absence of a response from them will I chime-in on that.


Ray



wrmiller19 said:
Ah...thanks for the tip on the groover. I'm no machinist, I just like playing with their machines. :)

The only lathe tooling I have is a little 3/8 set with indexable carbide inserts. They didn't work too well on the smaller lathe, but seem to do much better on this one. 1.5hp and better rigidity probably make a difference. When I get some 1/2" tooling I will try larger cuts. My little 0XA tool post is getting replaced with a AXA I ordered today. I don't like having the tool holder all the way at the top of the tool post.

I found my Inspection Report, and here's how my lathe tested out:

Geometrical Accuracy

Longitudinal Straightness of Bed: 0.03mm/500mm
Spindle Center Runout: 0.01mm
Spindle Shoulder Runout: 0.03mm
Spindle Bore Runout: 0.01mm
Spindle Taper Runout at Spindle Face: 0.01mm
Spindle Taper Runout at 100mm from Spindle Face: 0.02mm
Transverse Parallelism Between Spindle Centerline & Carriage Movement: 0.02mm/100mm (Only Up)
Longitudinal Parallelism Between Spindle Centerline & Carriage Movement: 0.02mm/100mm (Only Forward)
Transverse Parallelism Between Tailstock Centerline & Carriage Movement: 0.02mm/100mm (Only Up)
Longitudinal Parallelism Between Tailstock Centerline & Carriage Movement: 0.02mm/100mm (Only Forward)
Difference Between Spindle & Tailstock Centerlines: 0.03mm (Only High at Tailstock)
Perpendicularity of Cross Slide & Carriage Movement: 0.04mm/100mm (a > 90 degrees)
Longitudinal Straightness of Carriage Movement: 0.03mm/500mm
Axial Slip of Leadscrew: 0.01mm

Operational Accuracy

Accuracy of Outside Turning: 0.02mm
Accuracy of Cylindrical Turning: 0.04mm

I understand some of these, some I don't. All measurements were within recommended standards.

If these measurements are real, and based on my initial experiments, should I bother with the tailstock? Other than turning a long piece between centers, The only method I know is to put the dead centers in both the spindle and tailstock and pinch a small piece of flat steel in between and look for a vertical orientation of the piece of steel?

Bill
P.S. Maybe someone who is REAL bored can explain those measurements?
Click to expand...
 
I wonder why they ask $350.00 for the steady rest for the 8x18,when the steady for the 10" lathe is half that? It is unfortunate that the South Bend lathes(at least the bench models) come without the steady and follower rests. Most lathes come with 2 chucks,faceplate,steady and follower rest,a tool post,tool box with tools and the extra gears for metric threading.
 
george wilson said:
I wonder why they ask $350.00 for the steady rest for the 8x18,when the steady for the 10" lathe is half that? It is unfortunate that the South Bend lathes(at least the bench models) come without the steady and follower rests. Most lathes come with 2 chucks,faceplate,steady and follower rest,a tool post,tool box with tools and the extra gears for metric threading.
Click to expand...

I figure they are probably trying to keep the price on these comparable to "similar" lathes just for marketing purposes. A lot of people wouldn't look to see what extras came with it and would be most concerned with the price, so they can probably get by doing it that way. The guys on this forum are just more aware of the tooling extras costs than your average bear.

Price on the 8" steady may be a production issue. Some factory is set up to turn out the 10"s by the thousands but a special run has to be done for the 8s.

All just speculation though,

-Ron
 
I still haven't seen anyone mention that they have a 10" on all the forums I go to. They want so much for anything with the SB name on it.
 
Only once have I ever had the need for a four-jaw. The steady would fall in the category of 'nice to have', as I'm sure I'd find a use for it somewhere. But as someone else mentioned, this would have probably driven the cost up? Just speculation on my part.

I looked at (and drooled over) the SB 10k but I didn't want/need something that large/heavy. I really do work on small(er) stuff and my ability to move it around myself is a big factor in the decision process. The smaller spindle through hole and (much) higher price pretty much killed it for me.

I wouldn't have paid the 3k plus price for mine either. The reduced price brought it just within the range I was willing to deal with, albeit grudgingly.

Now if someone had offered a restored 9" for that 3k price I would have had to seriously consider it... :D
 
Several years ago,a machine dealer had 2 really nice heavy 10's mounted on cabinets w/underneath drive. Both had the taper attachment,hardened beds and as D type spindle and larger bore. One was fully equipped with 3 and 4 jaw chucks,steady rest,follower rest,faceplate,and other things. The bare lathe was $2000.00 the fully equipped one was $2500.00. Someone came in and bought the bare one!! I just had no space in my old shop,and wish I had bought the equipped one. I really didn't need another lathe as I have a Hardinge HLVH and a 16 x40" larger lathe. I just think the original SB lathes are nicely designed,with contoured castings that flow around their internal parts and artistic tail stocks. Had I known in a few years I'd be moving and building a larger shop,I would have jumped on it. The lathes were nearly new,especially with hardened beds and D style spindles. I'm still regretting I didn't get the good one. I had the money in my pocket. I like the extended range of threads that the SB lathes will cut. They go down to 224 TPI. and up to 8 TPI. My HLVH goes much less range than that. It has been an adequate range,but I like to be prepared for whatever comes along.
 
Sweet machine, i'm sure you will have hours and hours of fun there!!
good luck and best wishes!!
mike:))
 
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