SkiVisions File Base Flattener

(Updated 11/7/12: Revised instruction and NEW instruction videos at the bottom of the page)

The File Base Flattener is a powerful planing tool that uses a file to flatten concave (railed, edge high) snowboards and skis.  It is a different application from the steel blade in the Base Flattener, the steel blade is for fine flattening work, the File Base Flattener’s purpose is to cut through concave metal and plastic quickly.

New boards and skis always have some concave sections; they must be flattened for the board or ski to function correctly. A base that is concave makes the board or ski grabby and hooky, not smooth.  They make edge-to-edge transfers difficult and sticky.  You cannot relax on a concave base; you always have to be prepared for its next bad surprise.

From the top, you can see this is a two-hand push tool (for both power and control), with your rear hand on the larger bump.  ALSO OBSERVE THE STRIP OF WHITE PAINT ON THE LEADING EDGE OF THE FILE, THE FILE MUST BE USED IN THE TOOL WITH THE WHITE PAINT AS SHOWN SO THAT THE FILE TEETH ARE IN THE CORRECT CUTTING DIRECTION.

From the bottom side you see a 7-inch double cut file held in place with a  powerful magnet.  The front of the tool has a glide bar so the file sits flat to the base.  Notice again that the file has a strip of white paint on the leading edge, the file must be placed in the tool with that white strip facing forward as shown.  If the file is in the tool backwards it won’t cut your base and using it that way will dull it quickly.

Several points to keep in mind when using this tool:

1.  Always use the tool in the tip to tail direction.

2.  Use only moderate pressure, the file will cut metal and plastic without excess effort.

3.  Use only light pressure when running the tool off the tail, otherwise a) the file can get popped off the magnet, and b) the file will dig into the plastic at the curve of the tail and leave file marks in the plastic.

4.  Clean the file teeth after each pass with the supplied brush, only clean teeth will cut.

5.  If the file gets clogged with wax, use wax remover with the brush to clean them.

6.  If the File Base Flattener isn’t cutting edge metal on concave skis or boards,   then you have hardened edges, that hardening can only be removed with the green stones in the Ski Sharp.  See Tuning New Skis in the index for a discussion and procedures for this problem.

When used on snowboards, you flatten one edge at a time; observe the position of the tool on the board.  You are cutting from the center of the base through the outside of the edge.  But remember, since the board is concave, the tool is really cutting just the high plastic and metal near the outside edge of the board.

You take one pass down one of the edges, clean the file out with the brush that is supplied with the tool, then take a pass down the other edge, always rotating edge to edge so that the tool is used in a balanced approach and the board gets flattened consistently.

You will feel the file cutting the metal edges as you work.  You will also feel when the file no longer cuts metal, that tells you that the edge is then flush with the plastic base.  However, the board may still have some amount of concavity.  To bring the base to a totally flat condition because plastic needs to be removed, use the SkiVisions Snowboard Base Flattener with the stone blade.  You will have to rotate between both file and stone Base Flatteners to remove both plastic and metal if the base is significantly concave.

So how flat does a snowboard need to be?

1.  If the board is concave, you can get it flat enough with the File Base Flattener and it will work well on the snow even if there is some concavity in the plastic.  That concavity will soon wear away as you use the board.  And remember, if you use base edge bevel (as you should, see Snowboard Edge Tuning) any concavity on the base will be reduced in effect by base edge bevel.

2.  If the board is convex (rounded) you want to remove plastic and bring the board to a flat condition with the Snowboard Base Flattener using the 12-inch stone blades, convex bases do not work well on snowboards.  (See Snowboard Edge Tuning)

Use your true bar frequently to check your progress, you don’t want to over-do.  You will also be able to tell how you are progressing by how the tool acts as you start to get flat.

It is both a very aggressive tool and very easy to use, but don’t get carried away.  Take it slow, check your work often; you will get it flat soon enough.

When used on a ski, the file covers the surface edge to edge.  However, you can also use it on only one edge at a time as used on snowboards, this can make the flattening process go faster.  But again, remember, go slow, check your work often, don’t over-do.

Only moderate pressure needs to be used on the tool, it does not require “muscling it”.  And remember, only light pressure when running off the tail (see above).

See Ski Base Flattener for a thorough discussion on flattening bases.

Concave Bases, the first problem:

New skis and boards ALWAYS have concave sections.  They are caused by the manufacturer not letting it cool and age before grinding it, or by shipping it in very hot cargo carriers.  Regardless of the reason, the concave sections need to be removed for it to work right.  They may look great when new, don’t be fooled.  Oh, and when you go to the shop to buy, take your true bar and inspect (a ruler will do if not too flexible).  Buy the one with the flattest base and save yourself a lot of trouble.

The File Base Flattener is the only hand tool up for the job.  It is powerful (you can easily put 50 to 60 pounds of pressure on the tool) and uses a very sharp double cut file designed to simultaneously cut plastic and edge metal.  It is the “heavy machinery” of hand tools.

When factories grind skis and boards, they chase speed and efficiency.  Unfortunately, that also translates into work hardened edges and plastic caused by too much speed and pressure with the stone, and it can become a real challenge getting the tune on a new ski or board right.

Hardened steel edges are hardened on the surface only, about .001 of an inch, very shallow.  But, until it is removed, files, carbides, or steel will not cut it.  It is best removed with our 4 inch green stone with tape wrapped on one end for bevel.  Whenever you have concave bases you generally also have hardened edge sections.

If you observe that the File Base Flattener isn’t working, that is, isn’t flattening the base, you have hardened edges.  You can tell when the edges just seem to get slick and shiny but aren’t getting cut with the file teeth, because they can’t.

Sometimes it is a good idea to mark the concave edge sections with a felt tip marker so you can concentrate on those areas and watch your progress.

The following videos show using the File Base Flattener:

SkiVisions Using our File Base Flattener Part 1

SkiVisions Using our File Base Flattener Part 2

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