[zamazz]

Where does one get it? Every forum post or lapping procedure sheet for lapping mills seems to mention Aaron from IH, but seeing how he's no longer there and there is nothing on IH's website about lapping I'm lost as to where to get it. I've searched Google, eBay, etc and can find nothing other than super fine diamond compound and a couple grits of valve lapping compound, but where does everyone get the 80-500 grits, preferably in packages less than a pound?

[vertcnc]

Here is I have used on other projects. It is mixed with a lubricating grease. Don't know why it would work for ways.
Buy Loctite Clover Lapping Compound from UseEnco

[zamazz]

Here is I have used on other projects. It is mixed with a lubricating grease. Don't know why it would work for ways.
Buy Loctite Clover Lapping Compound from UseEnco

I did see those, but to get 3-5 grits is going to cost me over $100 and do I really need a whole pound of each grit for something I probably won't use for another 10 years? I also saw triumph powders, but there aren't many grit options. I've seen a bunch of people with a selection of black powders, and just wondered if there was a secret supplier.

[vertcnc]

if you have any local machine or tool and die shops you might stop by and ask. I know if seen other sources of just the grit that you would normally just add some oil, but can't remember where.

[hoss2006]

You can find a couple more lapping compounds here, Shop Info
You can also get the different grits in syringes like here on amazon for example.
Diamond Lapidary Paste 1200 Grit 10-20 Micron - Pre-polish, Fine Lapping 5 Gram Syringe: Amazon.com: Industrial & Scientific
Hoss

[USPcompact]

Be aware that if you use a hard lapping grit like diamond that it WILL embed in cast iron, and there's no wiping that off. I use flattened pieces of cast iron as a substrate for diamond compounds to sharpen chisels and plane blades. It's very impressive how little compound you need to sharpen effectively for a LONG time.

[zamazz]

You can find a couple more lapping compounds here, Shop Info
You can also get the different grits in syringes like here on amazon for example.
Diamond Lapidary Paste 1200 Grit 10-20 Micron - Pre-polish, Fine Lapping 5 Gram Syringe: Amazon.com: Industrial & Scientific
Hoss

Shoulda checked your site... I guess I'll call the American Lap Company tomorrow. I didn't foresee this being so expensive.

Be aware that if you use a hard lapping grit like diamond that it WILL embed in cast iron, and there's no wiping that off. I use flattened pieces of cast iron as a substrate for diamond compounds to sharpen chisels and plane blades. It's very impressive how little compound you need to sharpen effectively for a LONG time.

Yes, that's why I'm looking for the aluminium oxide variety. It seems to be on the rare side, however. The diamond is pretty easy to find.

[JRouche]

How bout some silicon carbide grit? Do an ebay search and you will find many inexpensive compounds. JR

Sumpin like this?

[hoss2006]

Yeah the compound in the syringe was shown just as an example that you can get small amounts pretty cheap and not have to buy a pound of it.
They do sell aluminum oxide grits in syringes too, we had a box full of them at work that we used.
Sorry for being lazy and posting the first link that google showed.
I thought we got ours at MSCdirect.
Hoss

[devincox]

I bought a set of this stuff to lap the ways on my IH Mill, years ago. I bought the mill used off ebay, and when it came in , I noticed it had already been lapped by the previous owner, so i never even opened the jars of lapping compound. Its probably been sitting for about 5 years now. I don't know if this stuff breaks down, if its still good and you want some, I'll send you some of the various grits for the cost of shipping and some beer. (c:

Devin

[zamazz]

I bought a set of this stuff to lap the ways on my IH Mill, years ago. I bought the mill used off ebay, and when it came in , I noticed it had already been lapped by the previous owner, so i never even opened the jars of lapping compound. Its probably been sitting for about 5 years now. I don't know if this stuff breaks down, if its still good and you want some, I'll send you some of the various grits for the cost of shipping and some beer. (c:

Devin

I tried to send a PM, not entirely sure it went through.

[Tex-VA]

I have had good luck with "Timesaving Lapping and Polishing Powders" McMaster-Carr They aren't supposed to "Charge" the metal you're lapping. Tex

[1HobbyMachinist]

Dapra makes an excellent lapping compound. It is called Biax.

[691175002]

I used triumph on my g0704 and it worked great ( MusicMedic.com: Triumph Lapping Compound ).

Very cheap, non-embedding and 400 grit cuts fast. I can't really see why you would need anything coarser. The time spent cleaning out a coarse grit would be longer than just starting with 400 to begin with.


Be careful, because any lapping compound that embeds (silicon carbide) will ruin the surfaces permanently.

[JRouche]

Very cheap, non-embedding and 400 grit cuts fast. I can't really see why you would need anything coarser. The time spent cleaning out a coarse grit would be longer than just starting with 400 to begin with.


Be careful, because any lapping compound that embeds (silicon carbide) will ruin the surfaces permanently.

Oooh.. Good info. I didnt know SC embeds. Solly for that recommendation. Does it embed because its so sharp? Good info.. Thanks for the info... JR

[wizard]

Lapping your ways in the manner that these grits allow is a very bad idea!!! You will get dozens of people telling you I'm wrong but I'm going to try to get you to ignore them one more time.

The problem is pretty simple, rubbing two pieces of metal together in the manner that is done with these grits leads to surfaces that aren't flat. You have no control what so ever as to where metal is being removed. At best the saddle, which should be married to the ways, will end up with bearing surfaces that aren't flat and can not support the load as intended. Beyond that removing embedded grit is a real problem.

Consider for a moment how telescope makers grind their lenses and mirrors as one data point. If that doesn't sell you, consider looking through some machine tool rebuilding references about the how's and whys of scraping in plain cast iron bearings.

I'm not sure how lapping the ways, as described in these forums, became so widely accepted but it is well worth it to educate yourself as to how these bearings are suppose to work and to what happens when you lap objects like this together. Anecdotal evidence here doesn't imply that the person offering up the evidence actually understands what he did. Nor does this so called evidence means that you will get the results you want.

I did see those, but to get 3-5 grits is going to cost me over $100 and do I really need a whole pound of each grit for something I probably won't use for another 10 years? I also saw triumph powders, but there aren't many grit options. I've seen a bunch of people with a selection of black powders, and just wondered if there was a secret supplier.

[USPcompact]

Lapping your ways in the manner that these grits allow is a very bad idea!!!

Lapping alone certainly is a bad idea if you're trying to achieve flat and parallel ways on a new machine. Lapping without a reference cannot and will not achieve that goal. With a reference, however, lapping certainly can produce flat and parallel ways, but why would you want to spend the time required to do this when you could just scrape?

However, I'm not certain that lapping the machines under discussion in this forum is always a bad idea. At best, lapping will not improve the machining tolerances the mill is able to hold (and it may make those tolerances more consistent), but it certainly may make the mill more user friendly at the cost of a reduced life span of the mill by accelerating the wear of the ways. How much the useful life of the machine is reduced and whether this is even significant is an open question.

Just my 2¢...

[zamazz]

I've already scraped the most of the machine to correct some geometry errors, but I only scraped to about 25% spotting. From here I wanted to lap to increase contact area and make everything a little smoother. Will aluminum oxide embed? I was under the impression that is was pretty soft.

[wizard]

Lapping alone certainly is a bad idea if you're trying to achieve flat and parallel ways on a new machine. Lapping without a reference cannot and will not achieve that goal. With a reference, however, lapping certainly can produce flat and parallel ways, but why would you want to spend the time required to do this when you could just scrape?

This is true with a reference and the right lapping tools you can achieve a flat surface. However is that resulting flat surface a good thing for a machine tool? I'd say no because one of the results of scraping is lower stiction.

However, I'm not certain that lapping the machines under discussion in this forum is always a bad idea. At best, lapping will not improve the machining tolerances the mill is able to hold (and it may make those tolerances more consistent), but it certainly may make the mill more user friendly at the cost of a reduced life span of the mill by accelerating the wear of the ways. How much the useful life of the machine is reduced and whether this is even significant is an open question.

Just my 2¢...

The issue of the impact on useful life is a good one and frankly that depends upon the person doing the work and the materials used. In some cases we have postings here of people trying to correct what appear to be geometry errors, that implies a lot of lapping leading to uncontrolled wear concentrated on the saddle. I just can't ever see this as being a good thing.

The other end of the spectrum is guys just trying to lessen the roughness due to the nature of the machining work on the ways. The goal, a smoother sliding fit, isn't bad by any means; I'm just not convinced that lapping with your saddle is a smart move.

Another way to look at this is how quickly machines used to machine castiron or other abrasive materials wear out. It can be rather fast even if the user puts reasonable efforts into cleaning the machine. Grit in the system never leads to nice even wear. Now granted the expectation is that the ways and dovetails will be completely cleaned after the lapping but even so I can't see a proper fit especially if the lapping is done with excessive aggression.

I guess the biggest problem I see here is people assuming that they need to lap the machine without even considering the specifics of their machine. The quality of these machines is highly variable, just because one example needed a specific correction doesn't imply that all examples do. The old don't leap before looking warning.

[wizard]

If you have the tools and equipment to scrap properly then why not go to 70-80% contact. Frankly it isn't any more difficult than lapping. I can understand to a certain extent people trying to lap in their machines if they don't have the tools and skills, but if you have the tools why not go to the point of a finished job? In the End the scraped surface will give you the best surface for a plain cast iron bearing running with way oil. If the geometry is right and the saddles married properly you should have smooth action over the usable length of the ways.

If the ways and saddles end up too smooth in relation to each other you end up with stiction much like two piece of metal wrung together.

How does the saddle feel on the ways now when assembled with an adjusted gibb?

I've already scraped the most of the machine to correct some geometry errors, but I only scraped to about 25% spotting. From here I wanted to lap to increase contact area and make everything a little smoother. Will aluminum oxide embed? I was under the impression that is was pretty soft.