Lathe level questions and probably other questions coming up.

[ShawnR]

Since the "researching lathes in Canada" thread has resulted in a purchase, I thought I might put general lathe questions in a new thread.

So, after making a few chips and exploring the new machine (PM1236 if you did not see the other thread), I figure it is time to "level" it. I have watched many of the popular youtubers and their levelling explanations and think I get it. I got a machinist level but that may have been a waste of money. Tooooo sensitive, I think but we will see. I am just getting going. After roughing the level in with a carpenter level, I find it is pretty good longitudinally, but tilts down in the front. I tried making some cuts in a 1.25 rod, chuck to center. Some videos show work piece between centers and some chuck to center and one no tail stock support. My initial cut was over .005 in about 20 inches. (and a crappy finish but my tool sharpening skill set could be a whole new discussion thread)

My real problem right now is how to lift this machine and stand to shim. I was able to lift the tail stock cabinet with a crowbar but the headstock it too heavy (working alone) I could get someone to put a shim in while I stand on the crowbar, but then I need to make another cut, scratch my head, do it again, etc so it could take a while and everyone is busy these days.

So, any input on leveling? I am considering making 4 plates to go under the 2 cabinets, incorporating adjustment screws into them. I would use 3/8" flat bar and span the width of the cabinet. The head stock cab would have two adjustments on each plate the tail end one (see photos)
But to lift the cabinet, (to shim or install a new plate if I make them) I am planning on making a tool to use a hydraulic jack as in photo. To keep the angle from pivoting down, there is just a piece of solid wood in the cavity, under the angle. What do you guys think? I don't think it is possible but wondering if forces would break the piece of cast out of the bottom of the stand. It is not designed to be loaded in that direction. I think without the wood, the jack would just pivot out. Or should I just get someone to stand by while I work my way around the machine and lift it up to some height whereby I can get an adjustment plate in there?

 

[Darren]

I made levelling feet for my Emco. It was way too low for me without them. Made precision levelling very easy. Took about an hour to level it, but i need to go back and double check it as its been about a month now.

Theres a hockey puck inside there

As far as shimming goes, I had to do that on my surface grinder. I used two prybars, one to lift and one to wedge while i inserted shims.

 

[ShawnR]

@dfloen that was my plan and even bought six of those sponge pucks. But then on one website, someone posted that a lot of the guys were taking their vibration dampening pads out so I did not end up using them. Instead of just not using the pucks, I did nothing for adjustments. And I have a short inseam so thought maybe it would be too tall with adjustments under it but it can certainly come up in height, even for me.

 

[DPittman]

You've probably understood this already but it is easy to confuse the idea of getting a lathe level and getting a lathe straight. A level lathe is good place to start but being level or not doesn't really impact how the lathe performs, (there are lathes on ships), being straight is what really matters.

A machinist level may be too sensitive for basic leveling of a lathe but that sensitivety is needed if you want to make sure the bed ways are straight.

 

[Darren]

@dfloen that was my plan and even bought six of those sponge pucks. But then on one website, someone posted that a lot of the guys were taking their vibration dampening pads out so I did not end up using them. Instead of just not using the pucks, I did nothing for adjustments. And I have a short inseam so thought maybe it would be too tall with adjustments under it but it can certainly come up in height, even for me.

Sponge pucks are no good, need hard rubber pucks. A jack screw/locking nut with a rounded point into a steel plate with a drilled divot would work too, and be lower.

DPittman is correct, level is not the idea. Its about taking out the twist to make it cut straight. Sometimes level doesn't even work if you are running coolant and need it to flow towards a drain, etc.

 

[Mcgyver]

to sensitive? Not sensitive enough....ideally you want the master precision level but unless you are into reconditioning (I am) its a bit of an extravagance. You can do the same with a machinist level then some trial and error.

You'd do well to incorporate some levelling bolts as shown above. You need that sort of sensitivity and its not set and forget, things shift over time, concrete moves etc so a convenient way to tweak it is really helpful. Also as noted above, level itself doesn't much matter, its just a convenient reference against which you are trying to remove twist.

After using the level, I check it by machining or sweeping something just held by the headstock. Involving the tailstock confuses things....leads to "is it twist or tailstock alignment?"

If its not clear why twist is the enemy, here's a diagram I did showing how twist affects diameter

 

[ShawnR]

Thanks guys. I am going to incorporate an adjustment into each corner. I need to lift it first though. I just welded up my device shown in the mockup and will see if it works. Get back to you later.

 

[ShawnR]

My jacking rig worked out great. I did need the block of wood inside the recess to prevent the jack from pivoting out but otherwise, made it very easy to lift the unit. I used 5/8" bolts cause that was the largest that fit through the hole in the bottom of the stands. I turned a taper on them that more or less matched my 5/8" drill bit, then made small pads to sit on the floor with counter sink divots in them (Thanks @dfloen for the tip...no pun intended..) The lifting plates were made from 1/2" plate from my scrap pile. I welded 5/8" nuts in as I did not have a 5/8" tap and honestly, figured this would be faster and easier.

I think they will work out ok. Will start the actual leveling process tomorrow. As replies mentioned above, I plan on rough leveling it, then start making cuts and see where I am at.

 

[Janger]

Nice lathe.

 

[Darren]

Just remember to check it in a few days, a week and then a month. Metal is liquid, it never stops moving. Precision leveling will prove that.

 

[ShawnR]

I had good success yesterday leveling the lathe. I started out making sure all feet had weight on them, then leveled with a carpenter level. I then started making cuts. First one was tailstock=1.176 and chuck 1.173. Made 4 adjustments, then realized that I probably should tighten the jamb nuts. I then made some more adjustments, then realized that I had the live center in... but finished up anyways to see what difference it might make. I was able to get it bang on, now at 1.1062 both ends (over only 8")
I then put the dead center in found it off a little. Maybe was me though. I went through the process again and was able to do two repeatable cuts at both ends equal. I am pretty happy with that. A new experience for me.

I will probably put a long bar in sometime and see what the difference will be over the entire length or at least, longer than 8 ".

I could not imagine trying to do that via shims. The feet were sweet!

Thanks for all of the input.

Cheers,

 

[DavidR8]

Nothing beats sweet feet!

I'll be moving along now...