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knocnocman
02-11-2015, 08:25 PM
I have an old SB lathe and would like to clean the ways. I was looking at lapping compound but not sure it is necessary. what is a good economic way to rehab the ways without damaging too much wear?
any tips , advice is appreciated thanks.:cool:

dalee100
02-11-2015, 08:59 PM
Hi,

Do you plan to scrape the ways for refurbishment? Unless there is active rusting and flaking, there probably is little reason to breakout lapping compound or similar things. At most, some kerosene or diesel dipped steel wool to remove grime is all that is needed. Bright and shiny isn't required. Just smooth and clean.

Dalee

Bill736
02-11-2015, 09:01 PM
If you're just cleaning the ways, I'd start with a solvent to remove oil, grease, dirt, and chips stuck to the ways. Mineral spirits or lacquer thinner will work , used with paper towels. Then, inspect the ways carefully for any small high spots caused by dropping tools or materials on the ways. Many people remove small high spots with a fine grade of sharpening stone. Don't worry about small pits . Now, you'll have to decide whether the ways have enough wear to justify a resurfacing . Usually, the worst wear will appear near the headstock , and will appear as a wide groove on V ways.
Whether that groove will cause significant accuracy problems depends a lot on what purpose you intend for the lathe. Two of my three lathes have significant wear grooves, but it hasn't bothered me for the work that I do.

knocnocman
02-11-2015, 09:16 PM
I will do that with the materials I have on hand, save the $$ on the lapping liquid. the ways are in really good shape for the age of the machine it did however get run into the chuck a few times as it has some chunks missing from the rest. old south bend gear change model.

Forrest Addy
02-11-2015, 09:36 PM
Noobs to the machine trades may be forgiven for not knowing this but mis-applied lapping is nothing more than accellerated wear. Well meaning but ignorant enthusiasts can do more damage to the remaining precision of a worn machine tool by lapping than by any other process. Anyone who recommends lapping as a workable process connected to machine tool way systems is crininally misdirected and should be ignored without exception.

Lapping has its place and can indeed yield exquisite finishes and accuracy in optics and precision gages but like fire its a superb servant but a terrible master. The average home shop machinist should cringe from the very mention of lapping compound and machine tools in the same sentence.

If you desire to enhance your machine's precision a thorough NON-ABRASIVE cleaning is a good place to start. That said, you must understand no amount of cleaning or adjustment will magically "un-wear" a machine tool. If your machine tool is unacceptably worn you are faced with a decision: replace or re-condition.

Reconditioning is not paint and repair of externals. It is a full condition survey of the machine as it exists, followed by an assesment and eventually the machining/scraping of the machine's way bearings and other components until it's restored to like new condition, accuracy, and durability.

There is a harsh reality to be dealt with here: quite often the cost of re-conditioning exceeds the cost of replaceing it with a new, more modern machine tool of equal size, capacity, and quality. Shrewd scrounging, contact building, trading of favors, etc go a long way to reduce the cost of reconditioning your machine. There are ways of doing the job incrementally - all with the understanding that such a path takes far longer as it saves you out of pocket expense. In the meantime there will be periods when vital machine parts are under repair and you cannot use your machine.

becksmachine
02-12-2015, 01:52 AM
What Forrest said X2.

I would add, it is nearly impossible to do a thorough job of cleaning ways without removal of the carriage from the bed. At the very least, remove all way wipers, if so equipped, and flush with copious amounts of oil while cranking said carriage from end to end of the bed. Same goes for the cross slide.

Dave

loose nut
02-12-2015, 10:23 AM
If the ways are just "browned" then leave it alone, you will do more damage trying to remove.

Fasttrack
02-12-2015, 12:17 PM
Noobs to the machine trades may be forgiven for not knowing this but mis-applied lapping is nothing more than accellerated wear. Well meaning but ignorant enthusiasts can do more damage to the remaining precision of a worn machine tool by lapping than by any other process. Anyone who recommends lapping as a workable process connected to machine tool way systems is crininally misdirected and should be ignored without exception.


^^^This :)

Since you are new here, I will just point out that Becksmachine and Forrest Addy (along with a number of others here!) have a lot of experience when it comes to reconditioning old machine tools and their advice should be given great credence.

That said, if you have actual rust on the ways, a quick lick with a maroon Scotch-Brite pad will do an excellent job removing the surface rust without doing significant damage to the way, especially if the ways are hardened. If the surface is smooth but discolored, don't use any abrasives! Just leave it alone.

The first step is to clean everything with a degreaser/solvent. As Becksmachine pointed out, this means you should disassemble as much as is practical and flush as much as possible from any areas that cannot be directly accessed/seen. Once everything is well cleaned, you can see what condition the surface is in. If it was "protected" by gunk, then it probably not seriously rusted or harmed, although it may be discolored. If you find it has raised, rough rusty patches, hit those with Scotch-brite pad or even a piece of crumpled up aluminum foil. Make sure you wash all of the rust and other abrasive dust from all the surfaces before re-assembling and oiling.

Alistair Hosie
02-12-2015, 04:35 PM
If you don't have experience with this type of thing then invite a friend who does over before applying your own limited knowledge to the practical side of renovating this MY " Cents worth.I agree Forest is along with Becks and a few others here know about these things.I am just a poor boy with absolutely zero experience of this type of thing.When I bought my lathe I subsequently had a few good machinist pals over and inspected my new purchase and commented the bed ways were like new.It was used previously by oxford university from new,and was well looked after,So I was lucky plus the guy who sold it to me was a really nice honourable gentleman .Alistair

browne92
02-13-2015, 10:10 AM
My limited experienced tells me that lapping papers and compounds are used to mate two surfaces to each other, not for cleaning.

I am curious about what the experienced here think of using a wire brush for really caked on grime.

Fasttrack
02-13-2015, 10:33 AM
My limited experienced tells me that lapping papers and compounds are used to mate two surfaces to each other, not for cleaning.

I am curious about what the experienced here think of using a wire brush for really caked on grime.

I wouldn't have a problem using a stiff nylon or brass brush. What works even better, though, is to make yourself a gunk-scraper out of some scrap copper sheet. I find it does a more thorough job of getting the gunk off and I feel like I have more control.

Rosco-P
02-13-2015, 01:27 PM
I am curious about what the experienced here think of using a wire brush for really caked on grime.

Id use a plastic paint scraper, copper wool pad or brass wire brush before resorting to a steel or stainless steel wire brush, steel wool pad or Scotchbrite pad of any grit.

J Tiers
02-13-2015, 09:29 PM
First question is: Do the ways NEED cleaning?

If you think so, WHY do they need cleaning?

The "why" is mixed up with what is on them that makes them "dirty". And that is mixed up with the correct means to remove the "problem", if there actually is one.

Might just need solvent, might just need wiping, might really need to be scraped or ground back to a good alignment due to wear....... No good info given, so no way to tell.

The very FIRST thing to do is to figure out what (if anything) is really wrong with the machine (a survey). THEN the possible solutions are evaluated, and after that, the fix means is selected.