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Topics - RichColvin

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16
General Tormek Questions / Using 250mm stones on the T-3 / T-4
« on: December 21, 2018, 05:38:30 am »
Dan @ Exact Blade has provided two great ideas on getting more life from your grindstone investment, and I've cataloged them on the Sharpening Handbook.  Here's a link to the page where it is documented :

http://www.sharpeninghandbook.info/Grindstones-StoneLife.html

What I find most exciting are the pictures he provided.  These show his use of old 250mm grindstones on his T-3, grindstones that no longer worked on the T-7 / T-8.


Now I just need to buy a used T-3 or T-4.  Maybe there is a guy nearby who has one in his basement, possibly gathering dust in a bowling ball bag....

Kind regards,
Rich

17
Wood Turning / Great article: what steel gets sharpest
« on: December 16, 2018, 12:58:07 am »
Read this recently: 

https://www.morewoodturningmagazine.com/articles.php?articlesid=112&access=7e7d78763e40

Nice mix of experience and measurable data.

Kind regards,
Rich

18
I am so ever grateful to Ken Schroeder for loaning his diamond wheels to me.  I am posting my initial comments below about them.

The summary is this :  I don't see the value to them for me.  What it appears to be is :

Advantages of the diamond wheels
  • When reshaping a tool, the coarse wheel works well, even on tough metals.  It is probably a better choice than using the same jig on a traditional, high-speed grinder (via the BGM-100).  Indeed, I found I was able to easily clean up some past grinds (that were functional, but not that pretty).
  • Swapping out the course wheel for the finer ones keeps the shape consistent across the grind (makes the grind nicer looking on tools with large bevels, especially tools like skews -- though it doesn't necessarily make it cut better).
  • Moving between wheels is convenient as I don't have to re-adjust the universal support bar when grinding a tool with finer grits.
  • Unlike CBN wheels, these can be used for sharpening high carbon steels.
  • They are probably cheaper in the long run.
In summary, the diamond wheels seem great for production sharpening shops.


Advantages of the traditional grindstones
  • It is very easy to use the stone grader to go from a coarser grit to a finer one, and I didn't have to change the grindstone.  In turning, this is something I need to do often.  I rough turn using the course grit, and change to a finer grit as I approach the final shape (for softer woods, I even hone the edge).  Being able to use the stone grader is faster as I don't have to swap stones.
  • This is especially useful when changing which tool I am using (this is very common with my turning approach on the lathe).  Some tools, like the spindle roughing gouge are fine when using the course grit, whilst others like the parting tools greatly benefit from a finer grit.
  • The finer graded SB grindstone seems to produce about the same surface as the DF (fine) diamond wheel or possibly even the DE (extra fine) diamond wheel.
  • The SJ stone gives a better finish than the EF stone.
  • I can swap out the grindstones between the SG, the SB, and the SJ without having to swap out the water and clean out the tray.  I get back to work faster.
  • If I get too aggressive, I can always fix it by using the truing tool.
  • I don't have to mess around with special water additives.
  • They are cheaper in the short term.
In summary, the traditional grindstones seem great for the all-around woodworker.

What I especially like is that Tormek has the right option for what works for many different sharpeners. 

I'm interested in others' thoughts.

Kind regards,
Rich

19
General Tormek Questions / MB-100 Tests
« on: November 12, 2018, 02:37:42 am »
Today, I had to resharpen a standard old chisel (after finishing up some honey-do items).  This chisel doesn't have much sharpening life left.  In fact, I was not able to sharpen it to 25º in the traditional manner when mounted in the SE-77 jig (or even the older SVH-60 jig).  The only options traditionally were:
  • increase the angle, or
  • buy a new chisel.


Fortunately, we now have a third option: the MB-100 Multi Base!

So today, I took this fortunate opportunity to test the MB-100 Multi Base (and diamond grindstones) that Ken Schroeder so graciously loaned to me. 

The results of using the various grindstones are below.  Please ignore the burr on the edges :  the pictures are simply to show the faces after use of differing grindstones.

DC-250

DF-250

DE-250


This tool was then sharpened on the SB and SJ grindstones (still using the MB-100 ... with the same setup). Mainly, I wanted to see how well it would work.

SB-250 - Graded Course

SB-250 - Graded Fine

SJ-250


Then the angle was increased to allow for a micro bevel.  This worked quite well !  (The micro bevel is quite a bit bigger than normally put onto an edge, but this enabled the picture to show well.)

SJ-250 - Micro Bevel


And finally, the tool was honed on Razor Sharp paper wheel.  (Yes, that's the iPad's camera reflected in the edge.)

Honed on a Paper Wheel

My take-away is this :  Whether using the diamond or traditional grindstones, the MB-100 is a worthwhile investment.

20
General Tormek Questions / Diamond Wheels vs. Traditional Grindstones
« on: October 15, 2018, 09:50:19 pm »
I recently re-read a Tormek posting regarding the diamond wheels :

Quote
If you want to have an easy set up and save time by not having to true your wheel, a Diamond Wheel is perfect. ... If you want to be able to change the grit size during the sharpening, the Original Grindstone is the best option.

It seems to me that the diamond stones come with some upsides :
  • the diamonds can be used to sharpen harder metals (like carbides),
  • consistent wheel diameter makes for faster sharpening when changing wheel grinds (seemingly especially useful for a shop which sharpens for income), and
  • the wheel’s sides offer some flat-grind options where concave grinds may be problematic.

But it also seems to have down-sides (relative to the traditional grindstones) :
  • care must be taken to not damage the wheel (as you can’t use the TT-50 Truing Tool to fix a damaged spot),
  • they are a bit more expensive than the traditional wheels, and
  • there is more special care needed for the water additive.

I’ve seen no real limitations with the traditional grindstones, especially ones that can’t be offset by using the BGM-100 attachment with my traditional grinder (e.g., to sharpen carbide tools).  I’ve not seen the need to move to CBN wheels either, and these are widely used in the wood turning community.

I’m thinking of not moving to the diamond wheels.  Am I missing something ?

Kind regards,
Rich

21
General Tormek Questions / SVM knife jigs with paper wheels
« on: October 03, 2018, 12:57:58 am »
So I’d like to use the SVM knife jigs with Steve Bottorff’s paper wheels.  Rather than trying to rig up something crazy, I’m thinking of a modified USB.  Here are my first thoughts.  Interested in feedback.


Kind regards,
Rich

22
Scissors Sharpening / Nice reference on why we do what we do
« on: September 05, 2018, 10:17:30 pm »
This is a very high scale, bespoke suit maker :  https://www.kiton.it/en/content/scissors

23
Knife Sharpening / Raspberry Pi ... and Ask of Wootz
« on: July 01, 2018, 11:54:39 pm »
A few months ago, I added a web browsing computer to my sharpening station.  I find it great to be able to quickly look things up and have the information right there where I'm sharpening.  I especially like being able to easily pull up the user manual from the Tormek site.


What makes this very affordable for anyone who wants to do so also is the Raspberry Pi.  You can see it in the picture below.  It's the little black box on the bottom right of the picture (to give you a concept of the size, that is a 17 inch display).  The Raspberry Pi is in a case which takes it up to a whopping 4.3 in x 2.9 in x 1.3 in.


The cost :
  • Raspberry Pi Kit - $75
  • Monitor adapter (HDMI to VGA) - $20
  • Used monitor - free
  • Used keyboard & mouse - free


So, now the ask of Wootz :  I like your idea of a sharpening method, and it would be great to run the program you developed on a Raspberry Pi.  The Raspberry Pi runs a version of Linux which is a derive of Debian.  Please let me know when I can buy it !

Kind regards,
Rich

24
Wood Turning / Thank you Stig
« on: May 15, 2018, 02:43:59 am »
About a year ago, Stig told me that I should not just sharpen my lathe tools on the SB / SG stone, but I should also hone them on the leather wheel.  He said that a number of professional turners do this and it speeds up the resharpening.

Well, that took a while to sink in, but it finally did :  in a different way though.

Yesterday, I turned a wooden vase from ash, and performed an experiment.  All my tools are already shaped correctly, so I sharpened them using only the SJ wheel.  This worked far better than I'd expected it would. 

The tools I sharpened are all high speed steel, and include :
  • Spindle Roughing Gouge
  • Skew
  • Bowl Gouges (multiple)
  • Scraper Blade

I am really happy with how it turned out, and my wife loves it.  So Stig, thank you.

With kind regards,
Rich

25
General Tormek Questions / Rust inhibitors discussion
« on: May 07, 2018, 04:26:06 am »
Really good discussion about rust inhibitors (e.g., Honerite) on this AAW forum thread :

http://www.aawforum.org/community/index.php?threads/tradesman-dc-grinder.13706/

Kind regards,
Rich

26
For those who want to read the wisdom from our elders, this book :

Turning and Mechanical Manipulation, Vol. III
Abrasive and Other Processes not Accomplished with Cutting Tools

by

Charles Holtzapffel

was published in 1850, and then updated by Charles' son, John Jacob Holtzapffel, in 1894.

Recently, it was digitized by Microsoft, and is available at :  http://huk1.wkfinetools.com/02-Toolmakers/Holtzapffel/pubs/1850-turning-mManipul/1850-TurningAndMechanicalManipulation-Vol.3.pdf

There is some really good information about abrasives used in sharpening and honing that many might find interesting.  If nothing else, there are some really cool pictures like these :


  • Volumes 1 through 4 are available at that same site (to access them, change the volume number at the end of the web link above).
  • Volume 5 is considered the bible for ornamental turners, and it is not available via a digitized copy (though you can buy a Kindle copy). 
    • The Holtzappfels' contributions to that craft were so critical, that a whole host of information is published about that book alone.  Some really good information is at http://holtzapffel.org/index.html.
    • They made beautiful machinery, and one is no longer considered the owner of the lathes they built :  merely the current care-taker.  That is assuming you can find one for sale, and can also afford it.  (The last one sold was in 2012 for $228,000 - https://www.skinnerinc.com/auctions/2623M/lots/232 ).
  • The Holtzappfels never finished Volume 6, but it was published in 2011 using gathered data by John Edwards, a British ornamental turner.

Just some fun for your day !

I'm just happy my Tormek doesn't have a treadle to drive the wheel !

Kind regards,
Rich

27
Knife Sharpening / What causes scratches when using the platform jig ?
« on: April 23, 2018, 04:35:12 pm »
I made a 2d platform jig using a plastic cutting board, and the knives I sharpened on it also get scratches half way up the side.  I’ve read how others have the same problem.  Anyone know what causes this, and how to prevent it ?

Rich

28
Knife Sharpening / SJ grindstone vs paper wheel
« on: April 14, 2018, 03:03:05 pm »
I’ve read thru Steve Bottorff’s information about using paper wheels, and I get it about the speed advantage.  But I am limited in bench space and am wondering about the effectiveness of that method vs. using the Japanese stone.  Do both achieve the same level of sharpness, just in different time requirements?

Rich

29
General Tormek Questions / Sharpening Metal Lathe Cutting Tools
« on: April 10, 2018, 03:20:38 am »
For a while now, I've wanted to have a way to sharpen my metal lathe cutting tools.  As I noted in my Sharpening Handbook (http://sharpeninghandbook.info), these are not easy to sharpen in a normal manner.  In particular, the angles must be precise for best cutting action.

Shown below is what I've put together to achieve the level of accuracy desired.  It is a "sled" which rides atop the SVD-110 Tool Rest, mounted on a BGM-100.  I currently use it on a high speed grinder as even the black wheel (SB-250) is too slow for grinding the carbide tip.  But, with the new diamond wheels coming, it seems like I can move back to the Tormek.

This is the front (left) and the back (right)

The brown piece on the back is a piece of wood which rides across the SVD-110.  The black bar at the top rides on the SVD-110, opposite the wheel, along the back of the SVD-110.


The picture below shows it in use, sharpening a single point, cemented carbide tool on the high speed grinder.  You can also see the SVD-110 in the background (through the curved slot).


I still need to make an indicator of some sort for the hole over the protractor, and I don't have a milling machine, so it is a little rough looking.  But, I can tell you it works wonderfully !

Rich

30
Drill Bit Sharpening / DBS-22 & Japanese Grindstone
« on: March 25, 2018, 01:35:47 pm »
I had to sharpen a ¼ inch bit yesterday that I was using on a piece of ash, and the piece has no tolerance for tear out.  I sharpened the bit on the SB grindstone as usual, then finished the primary facets on the SJ grindstone.  (I didn’t worry about finishing the secondary facets as these are for chip evacuation, not cutting.)

This worked greatly !  Anyone else have similar experiences?  Has anyone seen differences with finishing the secondary facets also ?

Rich

By the way, this whole process took less than 5 mins !

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