GB2419108A

GB2419108A - A tool for smoothing rough surfaces

Info

Publication number: GB2419108A
Application number: GB0513199A
Authority: GB
Inventors: Victor Paul Holtrop
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-10-14
Filing date: 2005-06-28
Publication date: 2006-04-19
Also published as: GB0513199D0

Abstract

A hardened metal tool 1 used for smoothing rough surfaces commonly encountered in the building trade, furniture construction, boat-building and other industries, comprises a tubular shape truncated to present circular sharpened edges 4 which may be drawn across a surface to be smoothed. The metal tool may include a holder 5 for holding the tool with its sharpened edge in contact with the surface being worked. A mild steel fixing plate 3 may be spot welded to the middle section of the tool. The fixing plate may include a fixing hole (2, fig 1) that allows for a fixing bolt (9, fig 21) to be passed through the fixing plate and secured to the holder.

Description

DESCRIPTION

A TOOL FOR SMOOTHING ROUGH SURFACES

This invention relates to a novel device that is used for smoothing rough surfaces that are commonly encountered in the building trade, furniture construction, boat-building and other industries.

Various surfaces and in particular, wood surfaces require finishing treatment such as sealing and painting to protect the timber from the weather or to improve the look of the timber. As each coat of sealant or paint is applied to a surface it begins to dry. Surface roughness is caused by for example, air-borne particles such as dust settling on the surface, the grain or texture of the surface and brush marks created by applying sealant or paint to the desired surface. Any combinations of the aforementioned factors result in protrusions that rise above the general level of the surface and to a lesser degree depressions in the surface. If the protrusions are not removed before a further coat of paint is applied, they are effectively increased in height. Any depressions that may occur can be filled with a compound that hardens and bonds with the surface. This however accentuates the degree of roughness present on the particular surface in question. In order to produce a finely finished surface, surface roughness has to be removed before a further coat of sealant or paint can be applied to the desired surface There are several methods commonly used to smooth rough surfaces.

Sanding the rough surface by using sand-paper is one of the most common methods for smoothing rough surfaces, but sand-paper tends to become clogged up with the material it is removing and has to be replaced at regular intervals due to its easy deterioration through continued use. The use of sand-paper is fairly labour intensive and wasteful as often several grades of sand-paper have to be used in order to achieve the required degree of smoothness. While mechanically driven sand-paper discs or bands reduce the amount of human labour required, they do nothing to reduce the amount of wasted sand-paper that is generated by sanding and are subject to the same disadvantages that were mentioned earlier.

Using sand-paper without a backing block will allow the sand-paper to follow the shape of the surface including undulations, but this is a cumbersome process and is also quite labour Intensive. The use of a backing block behind the sand-paper will tend to flatten the surface by removing high spots, but its application is limited due to the fact that it is not suited to sanding undulating surfaces.

Another method for smoothing rough surfaces involves the use of a tool known as a cabinet scraper. A cabinet scraper essentially consists of a rectangular steel plate with dimensions of approximately 6 cm x 10 cm and about 1 mm in thickness. The cabinet scraper is moved forwards and backwards over the surface to be smoothed.

One ofthe disadvantages associated with using this tool is that its corners tend to catch on the particular surface that is being worked, thereby creating further deep scratches that have to be filled with the necessary filling compound and then smoothed again. A further disadvantage of using a cabinet scraper is that it cannot be used to follow the undulating contours of a surface.

This invention seeks to at least in part overcome these disadvantages.

A metal tool according to the invention is adapted to smooth surfaces and has a tubular shape truncated to present sharpened edges which may be drawn across a surface to be smoothed.

A tool as described may have sharpened edges which are circular.

The sharpened edges are preferably hardened.

In one form of the metal tool the outer edge is sharpened and the inner edger is rounded.

In another form of the metal tool the inner edge is sharpened and the outer edge is rounded.

Preferably the metal tool includes a holder for holding the tool with its sharpened edges in contact with the surface to be worked.

The metal tool may include a fixing plate adapted for attaching the holder to the tool.

The metal tool may be adapted to be machine driven.

The invention also provides for a composite tool including a mounting plate and mounted thereon a plurality of metal tools such that the tools may be operated to carry out a smoothing function simultaneously.

In such a tool the mounting plate may be adapted for hand operation or for being driven by a machine.

The outer cutting edge may protrude beyond the outer edge of the holder.

The outer cutting edge may protrude beyond the outer edge of the mounting plate.

The invention also includes a method of smoothing surfaces which includes the step of moving a tool as described in the preceding paragraphs over a surface to be smoothed.

THE DRAWINGS

The invention is now described, by way of non-limitng example, with reference to the accompanying drawings wherein: Figures 1 to 3 illustrate the tubular body of the metal tool without the holder.

Figure I is a cross-sectional view showing the top and bottom edges ofthe tool with a centrally fixed plate for attaching to a holder.

Figure 2 is a view from above the tool showing a circular fixing plate and method for attaching this by welds to the circular tool.

Figure 3 Is an oblique view of the tool.

Figures 4 to 12 illustrate the nature ofthe holder Figure 4 is a side view (3) of the holder for the tubular tool. The direction of view (3) is noted in Figure 8.

Figure S is a cross-sectional view on line A.A. with reference to figure 8, ofthe holder.

Figure 6 is a cross-sectional view on line C.C. with reference to Figure 8.

Figure 7 is a side view (I) with reference to Figure 8 showing an aperture in the holder through which the tubular metal tool protrudes.

figure 8 Is a plan view of the holder. The numbered arrows (1 to 4) show the direction of views in other Figures.

Figure 9 is a side view of the holder from direction 2 with reference to Figure 8.

Figure 10 is a side view ofthe holder from direction 4 with reference to Figure 8.

Figure I 1 is a sectional plan view on B.B of figure 5 figure 12 Is a view ofthe holder from underneath.

Figures 13 to 21 illustrate the tubular tool in its holder.

Figure 13 is a side view (3) with reference to Figure 17 ofthe tubular tool housed in the holder.

Figure 14 is a cross-sectional view on line A.A. in Figure 17 showing the tool fixed in the holder by means of a threaded bolt passing through the fixing plate into the holder.

Figure 15 Is a cross-sectional view on line C.C. in Figure 17.

Figure 16 is a side view (I) with reference to Figure 17, showing the tubular tool exposed by the aperture in the holder.

Figure 17 is a view from on top of the holder looking downward to the surface being Figure 18 Is a side view (2) with reference to Figure 17, showing the tubular tool protruding from the holder through the aperture.

Figure 19 is a side view (4) with reference to Figure 17.

Figure 20 Is a sectional plan view on B.B in Figure 14 m other words in a direction downwards towards the surface being worked.

Figure 21 is a view from beneath the tubular tool located in the holder showing the fixing bolt, spot welds, and location in the holder.

DETAILED DESCRIPTION OF THE INVENTION

One embodiment of the invention comprises a tubular tool I of hardened metal, a fixing plate 3 of mild steel having a fixing hole 2 for receiving a fixing bolt 9 which fixes a hand held holder 5 to the tubular tool I. Preferably the holder 5 is shaped so that the tubular tool I may be comfortably held and operated by hand. The tool I is used to smooth rough surfaces by drawing the same across the face ofthe surface.

The edges 4 of the tubular tool 1 are prepared for smoothing by grinding them on an emery stone with the tubular tool 1 at 90 degrees to the stone so that the circular side of the tubular tool I is in contact with the stone. A 90 degree corner is made on the outer and the inner edge of the wall of the tubular tool I. These edges 4 act as cutting edges in the sense that they cut the protruding roughness from the work surface while the tubular tool I is drawn across the surface being attended to. The cutting edges 4 may be hardened by normal methods such as case-hardening to increase the time for which they are effective before having to be resharpened.

A mild steel fixing plate 3 is positioned in the centre of the tubular tool 1 and secured with spot welds 6 The holder 5 allows for the tubular tool 1 to be operated by hand.

Alternatively the tubular tool 1 may be driven by machine. This description of the invention here is limited to its application as a hand held tubular metal tool 1 A mild steel fixing plate 3 is spot welded to the middle section ofthe tubular tool 1 A fixing hole 2 allows for a fixing bolt 9 to be passed through the fixing plate 3 and to secure a holder 5 to the tubular tool 1. The fixing plate 3 abuts onto surface 7 of the holder 5.

To smooth a surface the tool is moved across the surface so that the tubular wall of the tool is maintained at a 90 degree angle to the surface.

The tool may be moved in both straight and circular directions.

The tool will follow both undulating and flat surfaces.

The edges approach the protruding rough points from a multitude of directions which aids in efficiently smoothing the surface by a cutting action rather than a chiseling action.

The tool lends itself to being driven mechanically in an orbital, rotating, or linear direction This can be achieved by mounting the tool on a suitable mounting plate. In a further modification of the invention it Is envisaged that a plurality of tools are mounted on a mounting plate providing a multiplicity of cutting edges. Such an arrangement may be adapted for hand held use or for being attached to a machine which moves the tool. In a further modification the outer cutting edge may protrude beyond the outer edge ofthe holder or the mounting plate. This will facilitate smoothing where the tool must be used adjacent to a vertical surface.

The Invention offers the following advantages over the prior art: The tool does not clog up while in use.

The tool has no edges to dig into the work surface.

Claims

CLAIMS: 1. A metal tool adapted to smooth surfaces having a tubular shape

truncated to present sharpened edges which may be drawn across a surface to be smoothed.

2. A tool as claimed in claim I in which the sharpened edges are circular.

3. A tool as claimed in claims I or 2 in which the sharpened edges have been hardened.

4. A metal tool as claimed in any of the preceding claims in which the outer edge is sharpened and the inner edge is rounded.

5. A metal tool as claimed in any of the preceding claims in which the inner edge is sharpened and the outer edge is rounded.

6 A metal tool as claimed in any of the preceding claims which includes a holder for holding the tool with its sharpened edges in contact with the surface to be 7. A metal tool as claimed in any of the preceding claims in which includes a fixing plate adapted for attaching a holder to the tool.

8. A metal tool as claimed in any of the preceding claims which is adapted to be machine driven.

9. A tool comprising a mounting plate and mounted thereon a plurality of metal tools as claimed in claims 1 to 7 such that the tools may be operated to carry out a smoothing function simultaneously A tool as claimed in claim 9 in which the mounting plate is adapted for hand operation.

11 A tool as claimed in claim 9 in which the mounting plate is adapted to be machine driven.

12. A tool as claimed in claim 7 in which the outer cutting edge protrudes beyond the outer edge of the holder.

13. A tool as claimed in claim 9 in which the outer cutting edges protrude beyond the outer edge of the mounting plate.

14 A method of smoothing surfaces which includes the step of moving a tool as described in any of the preceding claims over the surface to be smoothed.