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In my opinion the reason why the countersinks do no cut well may be absence of sufficient relief behind the cutting edges. Similarly to drill bit, countersink cutting edge must have a relief angle also (typically 5 to 8°). Relief behind the cutting edge has even to be slightly larger and must continue around the "conical" surface segment of the countersink's tip. Strictly speaking it is not an exact right cone!

Jan

Hello Jan,

Any idea how a relief angle can be achieved? I have no idea (yet).

Serge

Serge, in my case there was some play in the jig, so it was sufficient to apply more pressure behind the cutting edge.

In your case the jig play is probably much smaller and so you can proceed similarly as when grinding a secondary facet on a drill bit. It means you enlarge the clearance angle by some 10 degrees and grind off segment of the "conical" surface behind the edge. It may be necessary to repeat this procedure for larger countersinks.

Use the marker, blacken the whole countersink surface and make a test countersinking. If the marker is removed from the conical surface you need to remove more steel here.

Jan

I didn't really follow the above conversation.  But, I believe what you need is some sort of cam that guides the countersink in that conical path, although it is a gradually changing conical shape and needs to continue for around 270 deg. in the case of a single fluted countersink.  This is how Drill Doctor does it (see photo) (except the DD photo shows a cam designed for a two fluted drill, so it is much shorter.

Rick

This makes sense to me.  By changing the stop or microadjust, you are changing the orientation and position of the USB and jig, but maintaining the bevel angle.  It makes sense that the LOC would change on the wheel.  If it didn't, you wouldn't have the same bevel angle.

Rick

My writing wasn't very clear... what I meant was, there was a difference between the 2 20° LOCs lines.  (See attached pic.)

That is how I took your statement(s). It still makes sense to me, IF, you are saying even thought the LOC differs for the two 20 deg knives, their angles are in fact still both 20 deg. 

Rick

Rick, thanks for the picture of a nice old radial drill press!

I hoped my could enable some simple milling work also, but thanks to the many degrees of freedom the construction is not sturdy enough.

Jan

Jan,

And depending on the way the chuck mounts to the spindle, a very bad idea.  If it is a taper mount without a screw that holds it in place (very common), with side thrust from milling, the chuck could come flying off the taper.  Drill presses are just not made for milling... 

For a number of years, I did a whole lot of good work on this type of mill:
http://www.grizzly.com/products/Mini-Milling-Machine/G8689?utm_campaign=zPage&utm_source=grizzly.com

Rick

It is hard to imagine, if the machine's head is locked in place, how it could not drill where it is lined up, as far as machine malfunction is concerned.  Easy to think of how the lack of center-punching, center-drilling and how the width of the center drill web could lead to wandering, especially with larger drills. 

Rick

CB,

I didn't get into how the facet grind of a drill bit affects wandering and breakout, but there is a very enlightening thread in the Drill Bit Sharpening Forum about a four and six facet grinds on drill bit points that may be of interest to you:
https://forum.tormek.com/index.php?topic=3265.0

The DBS-22 Drill Bit Sharpening Attachment is capable of putting both 4 and 6 facet grinds on drill bit points.  The DBS-22 was a prime motivation for me to invest in a Tormek:
https://forum.tormek.com/index.php?topic=3350.0

Be sure to read the "Drill Bit Geometry" article by Joseph Mazoff, mentioned by RichColvin in that thread.

Rick

Rick,

Is that the drill press version of a radial arm saw (which, there is a good reason you don't find sold new any more !) ?

Rich

Yes, and the only ones I've found sold new are huge, meant for metal working.  I have no interest or need for anything like that, although I would love to find and old Delta, as the one pictured.  Should the need arise, I have access to both in friends shops, but they are both 350 miles away. 

Rick

Rick, because we are discussing tools suitable for manufacturing the extension jig for Tormek, I hope we can post it here.

My radial drill press is similar to https://www.amazon.com/W1669-2-Horsepower-Benchtop-Radial-Drill/dp/B001R23SOA

My Universal 4" Cross Slide Drill Press Vise is similar to https://www.amazon.com/Universal-Cross-Slide-Drill-Press/dp/B001FGAJTA

The cross vise is mounted to the drill press table.

Jan

Jan,

Nice looking drill press.  And nice to have the cross slide drill press.  The type that I worked on is a bit different an larger and very hard to find.

Rick

Hey Rick, thanks for the offer.  Not really sure what's wrong, other than something is loose that makes it hard to line it up precisely.  (I'll line it up off, but when I flip it on, it'll drill in a different spot).  It's a cheap Harbor Freight many years old.... like Jan said, maybe time to be nice to Santa. 

If I get an idea what the problem is, I may give you a holler.

Curious.  There is a lot to think about there.  It would be helpful to hear what your "line up" process entails and what your drilling procedures are. 

It is hard to imagine, if the machine's head is locked in place, how it could not drill where it is lined up, as far as machine malfunction is concerned.  Easy to think of how the lack of center-punching, center-drilling and how the width of the center drill web could lead to wandering, especially with larger drills. 

The process I use, particularly when free-hand drilling, is: 1) carefully lay it out, with caliper scribed cross-hairs for each drill location, 2) precisely center-punch each location. I use a spring-loaded punch, but careful alignment of any punch is critical.  (If the punched point is off, move it, by placing the punch center in the divot and angling the punch away from the direction it needs to move and punching again. Repeat as necessary)., 3) center-drill to create a hole that the drill cannot deviate from.  4) begin drilling, with small drills, working up in small increments,  especially for larger hole sizes like 12mm and especially when using a drill press or hand drill where you cannot control the spindle (drill) speed.  In my case, the Delta is really a wood working tool, so it's slowest speed is too fast for drilling full diameter holes in metal, especially thinner thicknesses, such as the rectangular tubing I was drilling (Hence, my interest in installing a VFD).  I worked up in size by 1/16" dia. at first, but as the hole got bigger, by 1/32" dia.  Grip the workpiece tightly, but at the same time, loosely enough to let the drill find its center in the previous hole.  This means holding the workpiece itself tightly but allowing it to float/shift under the drill's pressure until it is centered.  The drill will try to grab the workpiece and spin it as it breaks through.  Best to be holding the workpiece in a drill vise unless it is large enough to make that moot.  I hope this makes sense. 

When drilling on my milling machine, using the DRO, I often dispense with the layout, but always center-drill prior to beginning drilling.  When drilling on the mill, where the workpiece is securely held, I'll often drill full sized, or work up in larger increments. 

Rick

I bought larger radial drill press with cross vise which I use for timber mortising.

Jan,

Please tell me more about your "radial drill press with cross feed".  I just posted about offering to help CB with his drill press and about having mounted a VFD to someone else's radial arm drill press.  But I never operated it in actual use, just confirmed that it ran under the VFD controls.  The notion of a cross feed is intriguing.  Do you mean something like and X and Y direction cross feed table?  I use my vertical knee mill, with DRO, in this fashion, but it is limited to just in travel the X and Y directions (although, I do have if fitted with knee milll travel DRO)

Since this is getting into non-"Tormek" territory, we may need to take this off the forum and into the PM or general personal email realm

Rick

Thanks for the additional info.

I actually do have a drill press... but have had some issues with it... so haven't used it... resorting to the ol' hand drill.  I think you have a good point though... and may see if I can get it up and running again before I tackle this.

CB,

What sort of issues have you had with your drill press?  I restored my Delta floor model, including changing out the spindle, repairing the push button switches and other stuff.  Plus I restored a 1941 Rivett 1020 lathe, which involved a lot of reworking of parts and making whole new parts by making patterns and having them cast in metal and then machining.  I want to convert the Delta drill press from single phase 110 AC to three phase by installing a VFD (variable frequency drive). I have the three phase motor but not the VFD.  I've installed VFDs on my Rivett lathe and my 6x26 vertical knee mill, as well as on two of someone else's Bridgeport mills and a radial arm drill press (Jan, I'll be asking you about yours).

If you would like to talk about it, we should probably PM each other personal emails so as to take it off the Tormek forum. 

Rick

If I turn the stop of the jig instead of the Micro Adjust to change the 2 degrees, is the difference in the bevel angles of the belly & tip compared to when using Micro Adjust?

This is an interesting question.  Initially, I would think there's no difference, until I thought of the pivot distance changing.

I did a bit of a dry run, just to see what popped up.  I set an angle of a knife at 17 deg. (all angles set/checked with the AngleMaster), and drew a LOC (Line of Contact) on the stone.  Then I adjusted the angle to 20 deg with both methods (3 turns with the MicroAdjust / 2 turns with the Jig Stop adjust), and drew a 2nd LOC for each.

With both methods the AngleMaster showed 20 deg.  But, there was about a 4mm difference between the 2 LOC drawn at the 2 20 deg. settings.  I could also see a slight difference in how the knife tracked in relation to their respective LOCs.

My thought is, it's not significant.  A good check would be to compare Sharpie marker removal, (but ran out of time... you might consider giving it a try).

Practically, probably not going to matter much.   

This makes sense to me.  By changing the stop or microadjust, you are changing the orientation and position of the USB and jig, but maintaining the bevel angle.  It makes sense that the LOC would change on the wheel.  If it didn't, you wouldn't have the same bevel angle.

Rick

My oldest granddaughter understands the BESS sharpness scale quite well, she knows that the device displays values in grams but that in fact measures force necessary to cut the test medium....her Lego sharpness tester model.

Isaiah 11:6
.... a little child shall lead them

When I first read about the Bess testor, I made a comment about it had the appearance that one ought to be able to fabricate one. Leave  it to the ingenuity of youth to show us old people!

What is the test medium and could we see a couple/few photos of the actuall BESS testing machine, please.

Rick

Rick, in my understanding obsession is in intimate relationship with creativity which is now considered to be extremely important for future development.    https://www.youtube.com/watch?v=iG9CE55wbtY

Jan

Rick, in my understanding obsession is in intimate relationship with creativity which is now considered to be extremely important for future development.    https://www.youtube.com/watch?v=iG9CE55wbtY

Jan

Thank you, I get that, but....

https://www.youtube.com/watch?v=iG9CE55wbtY

OOOO  MMMM  Fricking GGGG!  What a wonderful and powerful message. I posted the link on my FaceBook timeline. 

I see it in my granddaughter.  She loves music and dancing and I can so see how that could be "taught" out of her. She loves to have music played while we are driving.  She wants to have control of what is played (on the car stereo - bluetooth).  So, I hand her my phone and she plays what she wants.  She loves "The Bug" by Dire Straits (sometimes you're the windshield, sometimes you're the bug - splat).  So another song came on "Calling Elvis" and she asked "what is this song called".  I told her and she asked "what is an Elvis".  So, I downloaded some Elvis songs, and some Chuck Berry and Jerry Lee Lewis and now we are dancing our fool feet off to these classic rock n roll tunes.  I hope to be part of parenting that encourages her creativity. 

In another vein, so few children learn how to use tools and make things.  This is another area where I hope to create a learning environment for my granddaughter (Holly).  I am always making or fixing things.  When Holly was only about 9 months, my daughter made me promise to teach Holly all about tools and making things.  That was a no brainer.  I was already planning to do that, so making the promise was easy. Not yet 4, she knows how to use a cordless drill, a disk sander and has even "played" at grinding on the Tormek (actually just rubbing a dummy blade on the leather wheel, but she didn't know the difference).  She has safety glasses and ear protection.

Rick

Rick and CB, I follow with interest and satisfaction your progress in the construction of the extension jig. It reminds me of my efforts some two years ago.

Rick, do not be afraid about squarness too much. The extension jig is intended to work with the knife jig and here the squarness/accuracy requirements are not as big as for the square edge jig for chisels sharpening. (USB used for square edge jig has to be perfectly aligned with the grind stone axis otherwise it is hardly possible to ground a square bevel.)

Jan

P.S.: CB, drill press would be a suitable Christmas present for you! Write a letter to Father Christmas. Three years ago I have donated my old drill press and bench grinder to my brother, who is a woodworker, and he told me that it has changed his life. I bought larger radial drill press with cross vise which I use for timber mortising.

I understand and agree that squareness for the extension jig is not the same as for the square edge jig and maybe some others.  I just can't help myself.  Somewhere in the 1990s, my daughter correctly labelled my affliction as far as hobbies go: serial obsessions.  In that same time frame, she gave me a birthday card with this: "Happy Birthday to my serially obsessed, adolescent at heart Father". I still have that card. 

Drill press - YES!  I have three. A 1940 era bench top Delta (needs a motor), a restored floor model 1954 Delta and my small knee mill, which I use as a drill press, as well as for milling.  It has a DRO, so drilling holes in precise locations is a dream.  Latter has not been set up again since my move so I could not use it for drilling the XB-100 hole pattern. 

Rick

[many times]

I am a bit 'concerned' about getting the 12mm holes lined up right (I just have simple hand tools).  It'll definitely be a measure twice many times before drilling.       (Accuracy not always my strong suit).   

I think you'll do fine.  Establishing a good horizontal centerline is key as it will help keep the jig and USB square and horizontal (I checked the squareness of the USBs using a machinist's square... very impressive).  I aligned the 12 mm holes in the tube with those of the XB100, more for the aesthetics.  I don't think that matters as far as function goes, so focus your attention on getting those holes on the same horizontal plane. 

But, if that doesn't happen, you can always open the holes up a bit and shift the threaded rods up or down when tightening the nuts. There is a lot of wiggle room with nuts and washers that size.  I'd do that wiggling and final tightening with everything mounted on the machine and checking squareness in reference to straight surfaces on the machine.  Not sure how much it matters, but I'm fussy that way sometimes (most of the time )

Rick

Rick, your interest pleases me! 
It is an inexpensive and very versatile adaptor.

Jan

I have previously measured the spacing between the USB holes, and came up with 90mm also... so can at least confirm that.

Thanks to both of you for the info... I'll be building one... as soon as the parts come in.   

My implementation of Jan's extension jig is shown below.  I already had the XB-100 Horizontal Base and the 1"x2"x1/8" thick steel tubing, so I was able to get this far.  While I measured and posted the Base hole mount dimensions, I opted to clamp the base to the tube and spot drill the hole locations.  I tried clamping it square but something didn't work out and the jig was not square once mounted, so I opened up the jig holes and now it does. 

I also precision clamped the Base to the backside and spot drilled the first 12mm hole and then center drilled it.  Then took out the layout blue and tools and carefully layed out and center punched the location of the second 12mm hole.  Existing USBs slide in just fine. 

I used to live in Portland, OR, USA (a medium sized city) and could just run out and get things like M12-1.5 threaded rod and nuts.  But, a little over a year ago, I move to a tiny town in far NE Oregon with a population of 300, but it is in ranching country so it has two hardware stores.  Still, I had to order the threaded rod and nuts.  Will have to wait for them to finish the project. 

Rick