Although the main function of putty is leveling, if only putty is applied, only half of the leveling work has been done, and the other half is also the half that determines the effect, which should be solved by grinding. This is also the main function of wall grinding.

膩子批刮過程中，難免會出現一些微小的瑕疵，比如膩子交界處的接茬、局部批刮過薄或過厚留下的痕跡、墻面吸水造成的針孔等，這些瑕疵也是可以通過墻面打磨來解決的。

In the process of putty scraping, it is inevitable that some minor defects will appear, such as the connection at the putty junction, the traces left by local putty scraping too thin or too thick, pinholes caused by water absorption on the wall, etc. these defects can also be solved by wall polishing.

整體打磨后的膩子表面結構更加均勻一致，可以加強乳膠漆的表現效果，而且避免了因表面結構的差異可能引發的一些問題（如色漆局部色差等）。

The putty surface structure after overall polishing is more uniform and consistent, which can strengthen the performance effect of emulsion paint and avoid some problems that may be caused by the difference of surface structure (such as local color difference of color paint, etc.).

墻面打磨用什么工具？

What tools are used for wall grinding?

燈泡：為了能隨時觀察墻面平整度，打磨時，無論白天黑夜，工人一般都要在手里拿著一個燈泡。燈泡的瓦數一般都在200瓦以上，這樣即使白天也能很好的觀察到墻面的平整情況。

Light bulb: in order to observe the flatness of the wall at any time, workers generally hold a light bulb in their hands during grinding, day and night. The wattage of the bulb is generally more than 200 watts, so that the flatness of the wall can be well observed even during the day.

砂紙：打磨膩子的砂紙選擇是大家比較關心的問題，這里系統講一下。墻面打磨中常見的砂紙目數（每英寸的砂粒數）有80、120、180、240、320、400、600。其中80、120可以歸為粗砂紙，180、240為中等，320以上為細砂紙。砂紙過粗，容易導致出現劃痕，砂紙過細，很難打磨得平整，所以墻面砂紙的選擇，并不是越粗越好，也不是越細越好，而是與墻面膩子相匹配為宜。

Sandpaper: the choice of sandpaper for polishing putty is a matter of concern. Here is a systematic discussion. There are 80, 120, 180, 240, 320, 400 and 600 sand paper meshes (sand grains per inch) commonly used in wall grinding. Among them, 80 and 120 can be classified as coarse sandpaper, 180 and 240 are medium, and more than 320 are fine sandpaper. If the sandpaper is too thick, it is easy to cause scratches. If the sandpaper is too thin, it is difficult to polish it flat. Therefore, the choice of wall sandpaper is not the coarser the better, nor the finer the better, but should match with wall putty.

實際操作中，首先要以能把平整度做好為目標，墻面打磨多用240、320先進行試打，如果打磨起來不是很吃力，可以把平整度做得很好，那就繼續；如果感覺打磨很吃力，那就換用低目數的粗砂紙再進行試打。在保證了墻面平整度的前提下，如果一遍使用了粗砂紙，一般整體或局部還需要用細砂紙再打磨一遍，以消除粗砂紙留下的劃痕，并且讓墻面更加細致。

In actual operation, first of all, we should aim to do a good job in flatness. Wall polishing is mostly used. 240 and 320 should be tested first. If it is not very difficult to polish, we can do a good job in flatness, then continue; If you find it difficult to polish, use low mesh coarse sandpaper for trial beating. On the premise of ensuring the flatness of the wall, if coarse sandpaper is used once, it is generally necessary to polish the whole or part with fine sandpaper again to eliminate the scratches left by coarse sandpaper and make the wall more detailed.

按膩子質量來說。非耐水膩子由于表面結構疏松，所以比較容易打磨，一般都用240、320或更高的砂紙來打，不過由于大多數非耐水膩子質量都比較差，粉料本身的目數普遍較低，所以即便用高目的砂紙打磨，也很難打出非常細致的感覺。

According to the quality of putty. Due to the loose surface structure, the non water resistant putty is easy to polish. Generally, 240, 320 or higher sandpaper is used to polish it. However, because the quality of most non water resistant putty is relatively poor and the mesh of powder itself is generally low, it is difficult to polish it with High-Purpose sandpaper.

耐水膩子表面結構相對牢固，打磨要比非耐水膩子費力很多，尤其是一些高強型的耐水膩子，如果等到膩子完全干透后再打磨，就很困難了，這時候就需要先用粗砂紙把平整度做好，然后再用細砂紙打二遍，以求更好的效果。

The surface structure of water-resistant putty is relatively firm, and polishing is much more laborious than non water-resistant putty, especially some high-strength water-resistant putty. It is very difficult to polish until the putty is completely dry. At this time, it is necessary to do a good job of flatness with coarse sandpaper, and then hit it twice with fine sandpaper, so as to achieve better results.