Grinding and Honing / working up the grits

When honing a plane iron or chisel you may have a preference to type of stone or materials.

Names like India stone and Ceramic Stone are commonly heard.

Many materials are used as abrasives to grind and hone steel 

Man Made

Silicon Carbide

Aluminum Oxide

These materials can be also glued to paper producing sand paper

Also

 Diamond

And Natural (mined and cut right out of the ground)

Washita

Arkansas

 Some stones insist lubricant is needed to cut steel and so often we classify them accordingly

Oil Stones - Water Stones - Non lubricated Stones

In this class we will explore a variety of stones and sandpaper.

It is not obligatory to hone with only one category of material at a time.

the important thing to remember is that one must respect the order of grits.

The rule to remember is that the lower the number, the courser the grit.

For example;   A 320 grit is courser than 600 grit.

As a matter of fact, one can divide the grinding and honing process by grit,

Eg:  Grinding <  320 <  Honing

The confusing thing though is that there are other systems of grits too.

For woodworkers, the other system is Japanese 

As you can see a 500 U.S. grit is equivalent to a 1000 Japanese grit

 Most Japanese waterstones are Aluminum Oxide which has a characteristic called Friability.

Diamond Stones are the most durable.

So we use them here at RTC

Search the blog for grinding and honing articles. 

Perhaps comment about your experience.

Honing

Honing is the process perhaps most of us call sharpening

If you have ground your plane iron or chisel on a grinding wheel, the hollow grind will provide stability during the honing process.

whether using Oil Stones, Water Stones, Diamond Stones or Sand paper, the process of honing is the same.

The key element of the process is to create a micro-bevel

The micro bevel is usually about 5 degrees more than the ground angle

Therefore in this class  we grind at 25 Degrees and hone at 30 Degrees

The use of a honing jig is often handy to achieve perfect results

But I recommend mastering the skill without it.

It will be a frustrating journey but it's all in the name of craftsmanship.

search the blog for honing (Sharpening) opinions

Grinding

Grinding is done at lower grits to prepare or repair a plane iron or chisel before honing

Most often a grinding wheel is used because the process is faster 

The chisel or plane iron is placed upside down on a tool rest that is set to grind 25 degrees, the wheel produces a Hollow Grind

When grinding a 25degree bevel of a chisel or plane iron,

Be sure to grind the entire surface of the bevel.

it is apparent when the entire bevel is ground when only one reflection of light bounces back from the newly ground surface

 Only once this is archived may you proceed to the honing process

 In most cases if you are a true craftsman and take care of your chisels and hand planes, 

grinding need be only done once.

Search the blog for grinding tips.

Reading an imperial tape measure

You may say "I'm not good at fractions"  and so learning to read an Imperial tape measure can be intimidating at first.

But it's really quite simple once you grasp the dividing things up into groups concept.

The denominators of the imperial fractions are the same over and over again. I think this system has an advantage over metric because it reduces the amount of numbers one reads and therefore reduces mistakes.

Here are our famous denominators

/64           /32           /16           /8           /4           /2



Note 32nds and 64ths are not included on this drawing - But if you spot the pattern, a 32nd would appear between every line 

Watch these 2 short video on reading a tape measure

https://youtu.be/4YF6Zz0krXA

https://youtu.be/T6lCpPB2xKs

Now do these exercises below

Now if you are really brave, click on this link to read these measurements to the 16th and 32nd of an inch
After opening the link, select 1/16" or 1/32" increments and "inches only" before clicking on  Create it 

And finally take out your tape measure and measure the height of your desk.   answer in the comments below.