SB-250 Grindstone query

[Nevnz]

Hello Jeff

Have you heard from Tormek Sweden yet? You were waiting an answer - regarding my previous post questions to do with the new Blackstone Silicon grindstones in the General Tormek Questions section (April 04, 2009) and the Woodturning section (April 02, 2009). I am keen to hear any advice or feedback as to whether to go the SB-250 way or not. Thanks.

Neville

[Jeff Farris]

Neville,

Sorry for the delay in replying.  This summation is a combination of my recent experience with the SB-250 and the answers from the technical folks.

First, regarding the truing.  For both your SG-250 and the SB-250 the new TT-50 truing tool is a significant improvement over the ADV-50D.  I highly recommend it.

Laboratory results show that the SB-250 cuts high speed steel twice as fast as the SG-250, with half the wear.  That will vary somewhat with tool shape.  My experience would bear that out, though it did seem to me that the SP-650 Stone Grader was needed frequently to return fast cutting to the SB-250.  However, using the Stone Grader on the SB-250 refreshes the cutting action but removes almost no material from the stone.  It is quite surprising how little stone residue is in the water tray after an extensive reshaping session.

[Nevnz]

Thanks for that Jeff

It sounds like the TT-50 will be a good move. I had read some reveiws previously that stated the ADV-50D was still a better truing tool - so had hesitated to get the TT-50. Will the SB-250 stone take much longer to true than the SG-250?

When you say that the wear on the new SB-250 is half depending on tool shape - I am constantly sharpenening (touching up not reshaping) small bowl gouges and detail gouges (HSS) - will the SB-250 form ruts and grooves half as quickly as the SG-250? Or is it really only an improvement for wider profile HSS tools such as skews, chisels, planer blades and such like?

Thanks again Neville

[Jeff Farris]

Consider the source with regard to the review that claims the ADV-50D is superior to the TT-50.  A company that offers an accessory for the ADV-50D has no accessory to sell you, if you have a TT-50.  There is no difference in the time required to true the stone.

For sharpening (not reshaping), the SB-250 will show virtually no grooving at all, even on small tools. It is only when shaping that you will notice any grooving, and that is significantly less than with the SG-250.

[Nevnz]

Thanks again Jeff

You are right - it was that source (review/comparison of the old and new truing tools) and I did think at the time that there could be other motives behind it.

Thanks for all your helpful advice. Taking everything into consideration I think I will indeed benefit from upgrading both grindstone and truing tool.

Hopefully I will let you know how it all works out - once I have them and put them into use.

Many thanks - Neville

[sbachner]

My experience shows the TT-50 to be much faster and easier to use.