Instructions for use of Somma Resharpenable Quick-Change Cutoff Insert Circular Holders for Davenport Machines

Loosen clamp screw holding clamp wedge (Pt. 2) so that opening is wide enough to accept cutoff insert.

 

Install insert into holder.  Be sure pocket is free of chips and oil and that insert is pushed all the way in so that it bottoms out at back end of opening.

 

Clamp insert securely by retightening clamp screw so that wedge holds insert evenly and fully.

 

Tool is now ready for use.  Mount circular tool holder into machine and set cutting edge of tool to centerline of workpiece, same as any other tool.

 

When cutting edge needs resharpening, remove worn insert only (Do not disturb circular tool in machine toolpost) and replace with sharpened insert as per previous instructions.  Since clamping pressure is upward on insert, replacement insert will be on same centerline as original insert, thereby eliminating the need to reset tool for center height.  Also, since inserts are identical in form and have a parallelogram configuration, they will maintain same workpiece lengths and diameters.  Machine should be producing perfect parts again in less than a minute.

 

For best size control and for longest life, insert should be sharpened as soon as cutting edges start to show wear of .005" maximum.

 

To sharpen dull insert, install insert into RQCSF-CO sharpening fixture and clamp securely.  Tap insert down to be sure it is fully seated against bottom face.  Mount fixture on magnetic chuck of surface grinder horizontally or vertically depending on the wheel being used.

 

Remove stock evenly from entire top surface of insert so that top and bottom surfaces are parallel within .001" and as smooth as possible. It is essential that the top surface of the insert is flat and free of steps since steps would cause insert to not repeat center setting when remounted in holder and could also result in lack of rigidity and possible breakage of insert and damage to holder.

 

Grind off only minimum amount necessary to remove wear of cutting edges.  Remember, inserts should be resharpened prior to .005" wear.

 

Always spark out final grinding passes for better finish and longer tool life, honing of top surface will further increase tool life and improve finish.

 

Wheel grade recommendation for carbide inserts: CMD180  R100 B-1/8

Style of wheel: If grinding horizontally     Use D1A1

                      If grinding vertically         Use D11V9

 

Take .0001/.0003" deep passes if grinding dry.

Take .0002/0005" deep passes if grinding wet.

 

For best results true up wheel as per grinding wheel manufacturer's instructions as needed.

 

******************** WARNING ********************

It is always important to be certain that insert is clamped securely in the tool holder.  If insert is not clamped securely, machine damage or personal injury can result.

 

Extra care must be taken when you have resharpened the insert down to about 3/8" total thickness since it will no longer be possible to clamp the insert in the holder.  This is done intentionally so that insert will not be used when it's thickness is less than that which is required to support the cutting edge.

 

Therefore, it is important to be certain that clamp is actually clamping on insert, holding it securely in the holder and not merely bottoming out.

******************** WARNING ********************

If you have a specific broaching problem you need help on, please do not hesitate to contact us.