scratches on lathe bed

[mike scully]

hi do scratches on lathe bed eventually affect the lathes alinement and accuracy .I only have those little hairline scratches on the bed i have a powermatic 3520

 

[Dennis J Gooding]

Probably not in any one lifetime, because these scratches are extremely small. However, dings and burrs caused by dropping chucks and tools on the bed will quickly make it difficult to move the banjo and headstock if not dressed. I use a large flat mill file laid flat on the bed to gently knock off the burrs without reshaping the bed. There may be better ways, but this works. Be careful about trying to use hand controlled power sanding to clean up the bed, because you will eventually distort the face of the bed.

Dennis

 

[Mark Mandell]

Absolooootly

YES!

Those scratches will, by all means, allow both, your tail stock, your tool rest holder [aka "banjo" (deliver(ance) us from Hill People)], and (for a sliding headstock) other attachments, to grip the lathe ways way more securely, this INCREASING, the accuracy of your machine's set-up for any particular task. 😀

Remember, all that stuff that moves along the ways depends upon friction to stay where you put it. The scratched up ways = more friction, hence better grip. Flatlanders [who learned to dutifully wax and polish their table saw's top] need to relearn tool maintenance now that they've entered the world of Charybdis.😉


PS: Picky Picky Picky, I said "both" then made an open-ended list of 3 or more.😀

 

[Bill Boehme]

Those tiny scratches will lead to a disturbance of the Earth's magnetic field surrounding your lathe which will, in turn, lead to the inability of your turning tools to make perfectly smooth cuts. That will then lead to you developing a new vocabulary to more fully express your feelings when things don't go as planned. Your new expressive vocabulary will leave you out of good stead of polite company, meaning that you will become a social outcast and move to a remote cabin in the mountains where there is no electricity to power your lathe. Don't let your life spiral out of control -- polish those scratches out of your lathe bed now before it is too late.

 

[Mark Mandell]

Those tiny scratches will lead to a disturbance of the Earth's magnetic field surrounding your lathe which will, in turn, lead to the inability of your turning tools to make perfectly smooth cuts. That will then lead to you developing a new vocabulary to more fully express your feelings when things don't go as planned. Your new expressive vocabulary will leave you out of good stead of polite company, meaning that you will become a social outcast and move to a remote cabin in the mountains where there is no electricity to power your lathe. Don't let your life spiral out of control -- polish those scratches out of your lathe bed now before it is too late.

You left out " and will spend your days writing (by candle light) a Butlerian/Luddite manifesto on the dual premises that electrons are people too thus making all electrical power companies into slave dealers and, given the irrefutable existence of the Magneto-Gravitic Continuum, there is no such thing as a perfectly round object."

 

[john lucas]

Mark You and Bill are crazy. I hope you never get in the same room together, the world might end. 🙂
I never worry about scratches on my lathe bed other than to take out any high spots. For example if you drop a chuck on it and a sharp corner hits the be it will raise a slight shoulder. Carefully file this down flat but don't worry about the dent that goes below the surface. The low spots won't cause a problem unless you have a zillion of them. Excessive filling or sanding of the bed could cause some missalignment although more than likely it will simply make the tailstock harder to lock in place. That would have to be pretty extreme but I could see if you sanded the bed on a regular basis you could cause some alignment problems. I just use steel wool to clean of the rust. I never clean it with sandpaper and as I said would only knock of high spots with a file if dinged it badly.
You must be hard on your lathe. I've had my powermatic for close to 10 years now and have nothing but the tiniest marks in the bed. I learned years ago from a machinist friend never lay metal tools on the bed of the lathe. Now being a woodturner of course I lay my tools across the bed but most of the time it's the wooden handle that contacts the bed.

 

[Mark Mandell]

Mark You and Bill are crazy. I hope you never get in the same room together, the world might end.

Oh, so you're operating under the premise that spinning a large piece of a dead tree at 1,000rpm while shoving a razor sharp piece of steel into it is completely sane, right?🙄😉

 

[KellyDunn]

Mike, I keep a shop brush beside the lathe. Before I move the banjo I sweep off the bits of sandpaper grit on the ways. The little cuts allow a buildup of crud to get under the banjo. That buildup does not happen overnight. But it will happen. That will change the alignment. My ways can rust overnight here. I use a bit of 320 paper to polish the ways now and again. I also pull off the banjo and clean the bottom of it. I do use some wd40. Spray it on and wipe it dry. The only drawback is it makes it harder to get the banjo to get a firm grip. But within a week I can hardly move the banjo so do it again. I only clean the bottom of the banjo when I slide it and notice it left crud in a scratch mark. Even as hard as I try I still miss a bit of grit so am always making tiny scratches in the ways. But tiny beats a hunk of 100 grit. That really makes a scratch. When using the outboard I also use 60 grit so also try to brush the ways before moving the banjo.
One of our club members is prety new to turning and has the big oneway. He brought the banjo to a meeting as parts had rusted tight. He must have had a 16th of an inch of crud stuck to the bottom of the banjo. I told him he really should clean that more often. He said he had no idea it needed cleaning. Thats the worse I have ever seen. If he shows to our meeting in the morning I will ask how its going.
Also its very nice when the humor patrol gloms onto a thread. But it can be hard to see the truth they are saying when the tounge is so firmly against cheek.

 

[Mark Mandell]

Also its very nice when the humor patrol gloms onto a thread. But it can be hard to see the truth they are saying when the tounge is so firmly against cheek.

Actually, Kelly, when I got my Stubby [1000] Rob [the company owner] and Jordan [the US importer at that time] both told me to "git'er dirty" as raw steel, scratched on the top surface of the ways, will help lock things in place. Bumps and such don't help of course, but polishing the top of the ways just cuts down on the friction. I do brush stuff off, and I've been known to take a wallpaper scraper to the ways to remove glops of glue and finish. However, I've never had to take a file to them and I've never sanded or applied either wax or other kind of slickerer.

 

[Richard Coers]

I would say that scratching would reduce the friction. Two polished surfaces, brought together with a firm rubbing motion, will stick together. Two rough surfaces will not. Precision gauge blocks and surface plates work on this principal. Not saying the lathe bed will perform differently, but a polished surface has more surface contact area for more grip.

 

[Bill Boehme]

I would say that scratching would reduce the friction. Two polished surfaces, brought together with a firm rubbing motion, will stick together. Two rough surfaces will not. Precision gauge blocks and surface plates work on this principal. Not saying the lathe bed will perform differently, but a polished surface has more surface contact area for more grip.

True. And, don't forget precision tapered tool shanks, too (Morse and other tapers). A scratched and rusted and dinged MT drive center is far more likely to slip than one in good condition.

 

[MichaelMouse]

Getting silly here, too. You don't want dings with raised metal which will interfere with smooth movement of your components. Static friction comments about slick surfaces are silly, as we're speaking of a barrier in sliding situations.

I doubt that a quarter century of normal maintenance will ever affect the accuracy of your lathe to a noticeable level. If you have areas of galled, raised metal, remove them. Worst case might involve two passes with a mill file followed by 320 paper adhered to a block, with or without a bit of extra lube. It's a half-dozen passes at most. Might still be a bit of visual artifact, but if your fingers pass over smoothly, so will the mating component.

 

[John Jordan]

Actually, Kelly, when I got my Stubby [1000] Rob [the company owner] and Jordan [the US importer at that time] both told me to "git'er dirty" as raw steel, scratched on the top surface of the ways, will help lock things in place. Bumps and such don't help of course, but polishing the top of the ways just cuts down on the friction. I do brush stuff off, and I've been known to take a wallpaper scraper to the ways to remove glops of glue and finish. However, I've never had to take a file to them and I've never sanded or applied either wax or other kind of slickerer.

I didn't tell you that. I'm an advocate of daily cleaning with WD40 and steel wool/scotchbrite/fine sandpaper, in fact, I can't turn until I've done that. This includes removing the toolrest base ans cleaning and spraying the cam parts AND polishing the toolrest. Every time I turn-without fail. Modern lathes will lock just fine, as will my machine lathe, and the toolrest base can be moved with a couple of fingers. There's nothing more irritating than requiring two hands to yank and shake the toolrest or tailstock into place when it should move easily. 🙂

Anyone that has ever watched me demonstrate has heard the lecture-its the first thing I do.

John

 

[Mark Mandell]

I didn't tell you that.

Now you're gonna make me go back over how many years of emails? Hmmmm🙂

I do use dry lube on the sliding bed surfaces, but when I unlock the toolholder or tail, they slide just fine; no yanking involved.

 

[John Jordan]

You can't find an email from me that says anything remotely like that. I showed how I maintain a lathe in the videos I did in 1992. You must have me confused with Dave Ellsworth. 😀 He used to advocate rust on the bed when he used General lathes that wouldn't lock the tailstock very well.

John

 

[Odie]

I didn't tell you that. I'm an advocate of daily cleaning with WD40 and steel wool/scotchbrite/fine sandpaper, in fact, I can't turn until I've done that. This includes removing the toolrest base ans cleaning and spraying the cam parts AND polishing the toolrest. Every time I turn-without fail. Modern lathes will lock just fine, as will my machine lathe, and the toolrest base can be moved with a couple of fingers. There's nothing more irritating than requiring two hands to yank and shake the toolrest or tailstock into place when it should move easily. 🙂

Anyone that has ever watched me demonstrate has heard the lecture-its the first thing I do.

John

Howdy John......

The tool rest base and bedways are frustrating when they don't slide like they should.....but, the toolrest directly influences a turner's ability to function at top efficiency during the act of turning. I'm curious as to your methods of polishing the toolrest, and tool shanks (if you do the latter)....

As for the banjo, I believe many turners probably neglect to lubricate the cammed rod and slider.....until it becomes a two handed operation to adjust the position. (Most of us are not as articulate as we should be on maintenance that should be done regularly......good for you, that you do!) Anyway, I've made a small modification to my banjo for quick lubrication of the cammed rod. A small drilled hole directly over the rod allows me to squirt a little oil directly on top of the rod. A few push/pulls of the banjo to distribute the oil, and it loosens up.....back in business! (This little hole is capped, so as not to invite debris to enter the mechanism.)

Thanks for your input.........:cool2:

ooc

 

[Mark Mandell]

You can't find an email from me that says anything remotely like that. I showed how I maintain a lathe in the videos I did in 1992. You must have me confused with Dave Ellsworth. 😀 He used to advocate rust on the bed when he used General lathes that wouldn't lock the tailstock very well.

John

Why is there suddenly a Streisand song playing in the background? 😀

I don't, however, seek to get the bed rusty; it's clean but not waxed etc.

Of course, now that David's a Robust "dealer", he can hardly advocate rust on stainless steel beds.

 

[KellyDunn]

I logged on and reread my post. Man I must have been tired. Its the tailstock, not the banjo that will if not cleaned not line up over time because of buildup. I clean the bottom of the banjo also but please know I meant tailstock. The guy brough his tailstock to the meeting. It had 1/16th of crud buildup. And with that there is no way point A and point B arrive at the exact same spot.
Now, I am not sure if I have heard David Ellsworth say to not clean the ways etc. I have heard him say do not clean the rust from your faceplates as it provides more grip to the wood than polished metal.
And I will back John up as I have seen more than once his ritual of cleaning the ways etc before he starts work. And he chats to the group about it as he does it. And he did not start working till he was satisfied.
I dont demo remotely as much as John does but when I do I want the banjo and tailstock to slide. It takes away a bit of my concentration when i have to fight either. That little bit I think degrades ever so slighty the impact I want as a demostrator. It blocks a bit of the flow.

 

[John Jordan]

Howdy John......

The tool rest base and bedways are frustrating when they don't slide like they should.....but, the toolrest directly influences a turner's ability to function at top efficiency during the act of turning. I'm curious as to your methods of polishing the toolrest, and tool shanks (if you do the latter)....

As for the banjo, I believe many turners probably neglect to lubricate the cammed rod and slider.....until it becomes a two handed operation to adjust the position. (Most of us are not as articulate as we should be on maintenance that should be done regularly......good for you, that you do!) Anyway, I've made a small modification to my banjo for quick lubrication of the cammed rod. A small drilled hole directly over the rod allows me to squirt a little oil directly on top of the rod. A few push/pulls of the banjo to distribute the oil, and it loosens up.....back in business! (This little hole is capped, so as not to invite debris to enter the mechanism.)

Thanks for your input.........:cool2:

ooc

A little Wd40 and whatever sandpaper/scotchbrite is laying there. Lightly is all it takes since its done daily. Just removing any scuz. For my final hollowing cuts, I wipe a bit of parrafin on the rest and the tool shaft. I want as little friction as possible at that point.

John

 

[Bill Boehme]

A little Wd40 and whatever sandpaper/scotchbrite is laying there. Lightly is all it takes since its done daily. Just removing any scuz. For my final hollowing cuts, I wipe a bit of parrafin on the rest and the tool shaft. I want as little friction as possible at that point.

John

John, if you have not tried Johnson's Paste wax, I think that it would be worth your time to give it a shot. It made a huge difference in reducing friction for my hollowing rig (Steve Sinner rig). I also use it on most everything else -- toolrest, tool shanks, lathe bed, headstock, tailstock, toolrest base. It leaves things slicker than snot on a glass doorknob and no gooey reside like paraffin wax leaves.

 

[Mark Mandell]

John, if you have not tried Johnson's Paste wax, I think that it would be worth your time to give it a shot. It made a huge difference in reducing friction for my hollowing rig (Steve Sinner rig). I also use it on most everything else -- toolrest, tool shanks, lathe bed, headstock, tailstock, toolrest base. It leaves things slicker than snot on a glass doorknob and no gooey reside like paraffin wax leaves.

I use Robust tool rests as well as a Kobra for hollowing. As all the rest bars are hardened to R62 so the tools just slide along smoothly without any added slippery stuff. No nicks, dents, etc. either.

And John, You're right. It was David who told me about the grubby grab factor. I do, however, keep all my morse tapers polished and shining.

 

[Bill Boehme]

I use Robust tool rests as well as a Kobra for hollowing. As all the rest bars are hardened to R62 so the tools just slide along smoothly without any added slippery stuff. No nicks, dents, etc. either...

The friction that I was referring to with the hollowing rig was between the bar and the trap. There was really a lot of friction as the parts didn't have a smooth surface. Despite what Steve claims, I had to spend some time dressing up the boring bar and trap where they slide against each other using a diamond hone. While that helped a lot, it still required more force than desirable to make smooth precise hollowing cuts. Next, I used Johnson's Paste wax on the trap and bar; and the friction went way down to where the parts glide together as if they were on ball bearings.

As for the Robust tool rests, I have four or five so obviously I like them. However, as they come when new, the surface isn't slick enough for me. So, I get after it with Micromesh and polish all the way to 12000 grit. And, as you probably already guessed, I wax it with Johnson's Paste wax. I give the same treatment to my turning tools except that I use metal polish rather than Micromesh. I may need to install stops at the ends of the tool rest so that the tools don't just skate right off the end. 😀 J-K, of course.