Machine tool scraping, hand and power
Cavco scrapes machine tool ways and slides back to flat, straight and square, by hand where the work is fine and with power scrapers where the area is large. Straight edge masters from three inches to twelve feet, lasers, electronic indicators and levels say where the metal has to come off, and say again when it is right. Ways and slides are the largest category of work on our books, and we have done this since 1980.
Every rebuild ends here. A machine can be stripped, reground, fitted with new screws and bearings and still cut a tapered part, because accuracy is not a part you bolt on. It is a surface somebody brought into agreement with every other surface, a few tenths at a time.
What the work actually involves
Scraping is measuring, cutting, and measuring again. The reference says where the surface is high, a few thousandths of an inch of metal comes off those spots, and the surface is read again. That loop runs until the bearing is even across the whole area and the axis agrees with the rest of the machine.
- Fine work in small areas, gibs, and round bearings, where a power scraper cannot reach or would take too much. This is the slow half and the half that sets the final geometry.
- Large way surfaces and long slides, where the metal to move is measured in thousandths across feet. Faster, and true, when the operator already knows what hand scraping teaches.
- From three inches to twelve feet, so the reference suits the surface rather than the other way round. Blue on a master is still the most honest picture of a bearing surface there is.
- Two types of laser, precision electronic indicators and two types of level, with metrology software for plotting way surfaces and checking alignments as the work goes.
- Turcite, Moglice and Rulon, scraped in after fitting. A liner is only as good as the surface it beds against and the scraping that finishes it.
- A flat way is not the job. The job is a way that is flat, straight, and square to every other axis, checked against them rather than on its own.
Scraping or grinding, and usually both
Grinding takes a worn way down fast and flat. Scraping brings it into agreement with everything around it and leaves a surface that holds oil. On most machines the answer is both, ground first and scraped in, and the argument for one over the other is really an argument about how much metal has to move. Where the ways are hardened and badly worn, that starts on a grinder, and we can do that in place on your floor rather than shipping the machine out.
A craft that is getting harder to buy
There is no machine that scrapes for you. It is learned at a bench beside somebody who already knows, it is slow, and the people who know it are retiring faster than they are being replaced. That is the honest reason a tool room struggles to find this work now, and the reason we have kept training it rather than letting it go with the generation that taught us.
Lathe beds, saddles and cross slides. Mill and boring mill ways, rams, and quills. Grinder saddles and tables. Broach slides and index tables. Gibs, wear strips and round bearings. And the way liners in Turcite, Moglice and Rulon that get scraped in after they are fitted.
Questions we get
- Cutting a tiny amount of metal off a way surface at a time, by hand or with a power scraper, until the surface is flat and straight against a reference. It is how a machine tool gets its geometry, and it leaves a pattern of low pockets that hold oil so the slide floats rather than drags.
- Grinding takes the surface down fast and flat, scraping brings it into agreement with everything around it. Most real jobs use both, ground first and scraped in. Hardened ways that are badly worn usually start on a grinder. Soft ways, small areas, gibs and round bearings are scraping work from the start. We measure the machine and tell you which it is.
- Yes. Scraping is hand work with portable references, which is exactly what travels. It is why a machine can be brought back on your floor rather than shipped out, and it pairs with grinding ways in place, which we do with a proprietary process.
- Two things at once. The high spots carry the load evenly, so the slide does not rock on three points, and the low pockets hold oil so the surfaces do not run dry and pick up. A ground surface alone is flat but it does neither as well.
- Blue and a straight edge master show the bearing, and the instruments show the geometry. We work to a points per inch bearing across the surface and check the axis against the rest of the machine with lasers and electronic levels as we go. You get the numbers the machine finished on.
- It is slow, it is learned at a bench next to someone who already knows, and the people who know it are retiring. There is no machine that does it for you. That is why it is getting harder to buy, and why we still train it here.
Reviewed September 2026 by Cavco Machine Tool Rebuilding, LLC.
Tell us the machine and what it is cutting
Call, or send the make and model and what the finish or the geometry is doing. We answer the same day.