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Hollowing with John Jordan tools

Discussion in 'Woodturning Discussion Forum' started by Roger Wiegand, May 15, 2020.

  1. Roger Wiegand

    Roger Wiegand

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    This was the week I was supposed to have spent with John learning about hollow forms at the Marc Adams School. Perhaps it will still happen, but I bought a set of his large tools and have been trying to teach myself how to use them in the interim. About the third time (I'm a slow learner) I had a catch that threatened to break my arm I've decided that I really do need instruction going forward. (A piece of 3/4" steel rotating in a big circle at a couple hundred RPMs gets your attention!) I've made a half dozen increasingly nice pieces (thinner, smoother walls, smaller entrance holes, better looking shapes) using primarily Ellsworth style tools I acquired many decades ago after a class with him, but there are places I can't reach with the straight shank tools that the Jordan hooks get to pretty easily.

    I've searched the web and Youtube but haven't found a good instructional video on using these tools. Can any of you point me towards a good demo?
     
  2. Richard Coers

    Richard Coers

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    Last edited: May 15, 2020
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  3. David Shombert

    David Shombert

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    Roger, were you using the Jordan arm brace when this happened? I had one of those for awhile and never got comfortable with it. The tool just seemed easier to control without that arm brace. I've watched John do it a lot and, of course, it looks effortless when he does it. I love his tools, but I never got the hang of using the arm brace.
     
  4. john lucas

    john lucas AAW Forum Expert

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    Richard. I hope you meant turn at or above ce ter. When the tool tries.to catch and you above center it is pushed into space. When you are.turning below center it tries to pull.the cutter deeper into the wood. One thing that helped me was to put a negative rake on the top.of the cutter. It's a little less grabby that way. Still important to stay at or above center. I still hollow by hand occasionally to keep my skills up but much prefer using captured bar rig. I dont do enough hollowing of larger pieces to be comfortable doing it by hand and it's almost relaxing using my home made Jamieson rig.
     
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  5. Roger Wiegand

    Roger Wiegand

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    Yes, I had the arm brace attached, but in the most recent incident I was holding the tool on the round part ahead of the brace -- the divots in my arm from the time before haven't healed yet. I've been trying to keep the tool more or less on center. With the Ellsworth angle tip I'v been finding it works better when I rotate the tool slightly counterclockwise so the tip will be angled a bit downward, ie if 9 o'clock is level then twisting to 8 or 8:30 is less catchy while still cutting well. I haven't had much success in trying to replicate that presentation with the Jordan hooks.

    Thanks for the links to the article and video, I will watch them this morning.
     
  6. William Rogers

    William Rogers

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    Roger
    I have John’s 1/2” and 3/4” sets. My 5/8” set is a mixture of Simon Hope and Trent Bosch. I use all of them depending, but like the JJ tools. I have used the 1/2” “free” hand. As a learning I did a bowl using the hollowing tools just to be able to see. However my elbow/shoulder cannot take the abuse any more and I have a hollowing system. Anymore when I’m doing small hollow forms I set up the system even with the 1/2” bars. The tools can take the abuse, but my old joints can’t.
     
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  7. Roger Wiegand

    Roger Wiegand

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    And... oops! I suppose one of those laser thickness tools wouldn't be the worst thing. I would have sworn I was following the curve, but I was clearly cutting in a straight line. IMG_2125.jpeg IMG_2126.jpeg
     
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  8. Dennis J Gooding

    Dennis J Gooding

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    It's "Deja Vu all over again". I thought those tools died out 20 years ago with the advent of torque arresting boring bars.
     
  9. Roger Wiegand

    Roger Wiegand

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    Well, good point and one I've been contemplating. Two kinds of thoughts come to mind;

    One is that people who do this for a living use tools of this sort, presumably not because they don't know about or can't afford a "system". There must be a motivation, and perhaps one that involves better expression of what they are trying to accomplish, or perhaps speed, or something else. I haven't discovered that motivation yet, and haven't had the opportunity to ask.

    Two gets rather more metaphysical, if not epistemological; at what point does the work become a product of a machine rather than a work of craft? How something is made is probably not important to 98% of buyers or users of the object, but it is important to me as the maker. I haven't quite reached a conclusion on this one yet; on the one hand most of the real craft and "artistic" decision making certainly goes into the shape you create and how you make use of the natural variation in the wood to enhance that shape. On the other it seems like a slippery slope to just programming a CNC machine to cut out whatever shape you've imagined in whatever numbers you can dispose of. Cutting stuff on a lathe with hand-guided tools is pretty archaic after all.

    So I thought I'd start out doing it "by hand", just as I learned to cut dovetails and M&T joints with a saw and chisel before contemplating a jig. I'd like to think my machine cut joints are better for having spent the time understanding, carefully tuning and fitting joints (and screwing them up).

    And perhaps this is all BS ;-).
     
  10. Emiliano Achaval

    Emiliano Achaval Administrator Staff Member

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    The reason lots of turners use hand tools is that you can get a different shape than using a hollowing system. I wish I could tell you I know this because I'm one of those guys, but we heard this from Mike Mahoney during one of the 2 live remote demos he did for our club. I have had the Stewart Arm brace tool for over 20 years, I still use it, but mostly to smooth out the interior after i'm done hollowing. John Jordan is supposed to come to Maui, hopefully soon, he has tickets purchased.
     
  11. john lucas

    john lucas AAW Forum Expert

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    After counseling a friend who was having trouble hollowing with JJ tools turns out he was sharpening them too blunt. The heel of the bevel was stopping his tool from cutting. I was counseling him on the phone so took a while to solve it.
     
  12. William Rogers

    William Rogers

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    I guess it is how you look at it. All the pro that do this for a living are capable of hollowing by hand. However Trent Bosch and Lyle Jamison have developed systems and John Jordan sell the Elbo system (he only sells tools he uses). I don’t classify a hollowing system as a “machine”. I still by hand need to move the cutter by hand. I see it more as a jig. It is not like I set it up and flip a switch and it hollows the vessel. I have a camera system, but I still capable of going through the wall. I did this when I bumped the camera and didn’t realize it.
     
  13. hockenbery

    hockenbery AAW Advisor Staff Member

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    I’m not a professional. But I sold enough hollow forms to pay for my ONEWAY many times over.
    Got good enough to demo H Fs at AAW, 5 regionals, and dozens of clubs.
    Any HF larger than 4” diameter I turn with a Jamieson handle and homemade backrest.
    3” Christmas ornament balls I do hand held because I got really good at it and don’t own any small bars that fit the Jamieson. Lyle has told me dozens of times to use his system for ornaments too - just never seemed to be comfortable option.

    The Jamieson handle for me is faster and less wear and tear on the body.
    using a laser and now video make the process even better for me.

    I can hollow anything my tool will reach with the jamieson. No restrictions on form that I can envision. The back rest can pivot way to the side if needed.
    Using the Simon Hope or Bosch system there are definitely limitations on the form.
    But these work for most forms people want to turn.

    Also many pros who do hand hand hollow have a size limit where they switch to a supported system.
     
  14. Doug Freeman

    Doug Freeman

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    Why “pros” hollow by hand? Don't know definitively as I haven't discussed with them. Perhaps faster, but I suspect it has more to do with the aura around holding the tool in the hands.

    Ive done my share of hollowing with HH. While I can do it, and the more you do the better you get, the concentration required, especially after 5-6” depth, and the concern over a catch and losing yet another piece, took the fun out of it for me. I still hollow ornaments and small items HH, but the Jamieson system I have made it a lot more fun to hollow larger items by removing the anxiety of another blow up or an injury. One injury is worth the price of a system.

    To Emiliano’s point about HH being able to reach places a system can’t - yes, flatter top shapes closer to the boring hole can require a lot of fettling to get a system to get the right area. I use HH to start all vessels, its easy and not prone to injury, and can blow out chips frequently faster than with the system. The system is used to hollow the top, then I use HH to clean up those hard to reach areas, but they don’t require much tool overhang.
     
  15. William Rogers

    William Rogers

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    Al, just curious as what are the limitations using the Hope or Bosch systems. I have the Hope and also Trent’s extreme bent bar. Maybe I’m “most people” and since I don’t have the Jamison don’t know what I'm missing.
     
  16. David Shombert

    David Shombert

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    I have a slightly different perspective on the topic of hand-held vs. hollowing rigs. I've done some hollow form turning, but not a lot, and it's not something I want to put a whole lot more effort into. There are other things that call to me. But I've been around John Jordan some and I've watched him work, and I own one of his pieces. When I hold it in my hands and look at it, I recall the memory of watching him work. For me personally, my enjoyment of that piece is enhanced by knowing - and remembering - the level of skill that went into making it.
     
  17. Roger Wiegand

    Roger Wiegand

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    interesting discussion, thank you. I've been having fun (mostly) while doing hollowing. It's not a form I've ever explored before, for reasons I don't understand myself-- intimidation perhaps. I'm sorely tempted by something that will give me more control-- or at least less chance of injury. I'm not so worried about having to return firewood to the firewood pile, but as described above I have had catches that threaten serious injury.

    That of course begs the question of which one-- there appear to be a bewildering array of choices, each seemingly more gigantic than the next. My shop is big, but I really don't want it to get crowded, so I'm certainly not going to buy three. Each appears to have staunch advocates, which suggests that most do their job at least adequately. Off to do some reading! A shame that Totally Turning and the Symposium didn't happen, it would have been a good chance to put hands on the major varieties.
     
  18. hockenbery

    hockenbery AAW Advisor Staff Member

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    The limitations on the hope and Bosch systems are depth and width of the form.
    Depth is sort of obvious and probably not a valid restriction. Since the standard Jamison is depth limited.
    Most of the people doing 3 foot and taller hollow forms are using a Huge custom made Jamieson style system.

    I do mostly wider than tall face grain hollow forms.
    Did one about this size using the Bosch system and thought that was at the limit for reaching the widest part of the wall
    This on is 11 “ diameter.
    95B6BE38-EE37-4D33-8616-9A687567CC7F.jpeg

    This one is 13” diameter
    CE383D0A-0C30-4715-928D-AE096AD00B6D.jpeg Don’t think I could do this on with the Bosch but that is based on the experience with two smaller forms.
    Just can’t swing the handle wide enough to the right to hollow the wide part of the wall.
    You still need the travel to move from outside the form to 9+ inches inside the form to get the outer wall.

    I think I might be able to reach it with the hope.
    I have done a 17” diameter piece with the Jamison. Don’t think I could do it with the Hope or the Bosch.

    I don’t think these are significant restrictions that affect many turners.
    Every tool has limits. As well as every tool user.
    We get into trouble when we try to exceed limits of either
     
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  19. hockenbery

    hockenbery AAW Advisor Staff Member

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  20. Michael Nathal

    Michael Nathal

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    The Jamieson system has a versatile boring bar with two different pivoting heads and two different angles to insert them into the bar. To make hollow forms that are much wider than they are tall, (like flying saucer shapes) you put the straight shafted pivoting head in the 45 degree hole in the boring bar. I wonder if the Jamieson bar can be used with the Trent Bosch system to achieve the same shape?
     
  21. William Rogers

    William Rogers

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    As far as I know any boring bar can be used in any system. I can achieve the same angles with my Hope boring bar or use my “bent” bars to do the flyings saucer shape.
     
  22. Doug Freeman

    Doug Freeman

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    The best system is dependent on the application, ie the shape and size of the HF’s the user intends to make, as well as storage concerns. Ive noticed many choose an articulating type because they take less room to store, and they dont intend to make a wide range of shape or size.

    I wanted a system that could do a wide range of depth and dia, up to 18”-20” depth and 12-14” dia, and of course smaller. After researching all the systems and the boring bars/heads/cutters that would be needed, the jamieson system came out on top - it was either the best price or right at it, and seemed to provide the greatest flexibility. I store the d handle and backstop hanging from the ceiling. Again, your desired size/depth needs to be decided before hand so you price all needed components. FYI depth determines boring bar dia. There are not “hard” rules, you will find variation in recommendations. It depends on the particular piece of wood.

    If you get a system I highly recommend a camera system, not a purchased system but one you piece together. Mine cost me $65 since I had an old computer monitor, so its pretty cheap to do. The lasers work but a camera is far superior.
     
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  23. hockenbery

    hockenbery AAW Advisor Staff Member

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    The Bosch hollowing bars can be use in the Jamieson handle. I use the Bosch bars a lot in my Jamieson or Hope system.

    the Bosch Stabilizer shown below cannot be use with the Jamieson handle or backrest. They replace that function.
    One aspect of the Bosch stabilizer is that the pivoting takes place ii front of where the tool locks in. This makes it a stronger than being behind but you also have more stuff between you and the work. Since you just put it in the banjo it is perhaps the fastest system to set up.
    Different part to the trade off equations.
    1C8DA1CD-F595-43EE-90DC-A4773D14FB7A.png
     
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  24. Roger Wiegand

    Roger Wiegand

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    Have you published a description of how you built your system? I looked at some demos online and they were fascinating.
     
  25. Doug Freeman

    Doug Freeman

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    No. The particular camera I have is not available, but I saw one very similar in a thread here somewhere. It's a flat square 1-1/2 or 2" with the lens coming out of the flat face. I used a signal converter/power supply (~$25) for BNC from the camera to VGA for the old flat screen monitor. My camera was ~$40, the one I saw in the thread was ~$25. I made a simple camera mount - turned a dowel to fit the jamieson laser rig in place of the pen laser, screwed/glued a small square piece about the size of the camera, and mounted the camera to it with good double stick tape.

    Most people use a transparency to draw the tool tip on and then a line or 2 for wall thickness. I made a "target" template, with a circle in the center the correct size for the #1 cutter, then concentric circles in the correct position for actual wall thickness. I just reuse the same transparency, no drawing. The lens and the lens height above CL determine the scale seen on the screen. Using 2 rulers, one placed at the CL in view on the screen, use the other ruler to measure actual length of a value on the screen - 3" at CL measured a little over 9" on my screen, so I have ~3.1 scaling factor. The template actual size is 3.1x the value, so a 1/4" wall is actually ~0.775" from the tool edge on the screen. Pic of the template below.
     

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    Last edited: May 18, 2020
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  26. Doug Freeman

    Doug Freeman

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    I typically use my left hand placed on the boring bar bar just to the rear of the tool rest, and my right hand on the "D" bracket of the jamieson system. A hand needs to be up close to the tool rest for good control as the final thickness is approached and to smooth the surface. The articulating type might make that approach a little more difficult.
     
  27. Roger Wiegand

    Roger Wiegand

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    OK, the hardware side of this seems reasonably straightforward in any event, but it must require a fairly sophisticated bit of software to do the image analysis and infer the hidden interior position of the cutter from relatively small movements of the visible handle (and some hefty compute power to do it in real time). I've used systems that do similar tasks, eg for automated injection of cell nuclei, but those systems sell for $100K's, albeit for an accuracy of nanometers. Is there an open source software project that enables this? Most sites I've looked at seemed only concerned with the hardware.
     
  28. Michael Nathal

    Michael Nathal

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    What I was asking is if you can put the Jamieson bar into Bosch Stabilizer. The bar is the same 0.75 inch diameter, so it seems it could work. This would allow you to do the flying saucer shapes with the Stabilizer.
     
  29. Doug Freeman

    Doug Freeman

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    No, no, no......you misunderstand. The template is printed on a transparency and taped on the screen, with the bullseye located on the cutter. No computer, no software. The camera signal is sent to the screen. The pics below show the screen with bullseye on the cutter, and with the cutter inside a HF.
     

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    Last edited: May 18, 2020
  30. hockenbery

    hockenbery AAW Advisor Staff Member

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    no it is soooo simple.

    the camera is mounted above the tool tip and moves with the tool tip.
    The tool tip never moves relative to the tool tip.

    I have a backup camera on my truck. The hitch ball is visible in the camera.
    The hitch ball never moves in the camera screen when I back up.
    When I put a trailer on I back up until the trailer hitch covers the ball.
    Same principle in hollowing.

    A clear acetate is over the screen. I trace my tool on the screen cover.
    When the tool is inside the for I see the tracing of the tool nit the tool.
    If I drew my hitch ball on my cars screen I would see the balls outline in top of the trailer hitch.

    I add to that a line drawn at the tool tip the thickness I want the firm to be.
    When the thickness line is on the out side of the form the toll tip,is the proper thickness away form the outside
    Don’t cut any more.

    here is the amazing part. How many thousands of people hollow? How many I’d the have cameras.
    Trent Bosch’s genius is being the guy to put the two together.
    When Trent first showed it to me my reaction was like everyone else’s - how can this be it is sooooo simple....
     
    Last edited: May 18, 2020
  31. hockenbery

    hockenbery AAW Advisor Staff Member

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    A picture
    below is picture of a video screen so the video screen has been degraded twice by photos of a photo.
    But you can see the tracing of the tool and a second line drawn 3/16” away from the cutting tip.

    you can’t see the tool in the hollowform but you can see the tracing of it
    when the thickness band around the cutting tip touches the outside wall of the vessel we have the correct thickness.

    54CF183B-4207-4ACB-8315-37605D0F5B75.jpeg



    This is the template I use to trace a thickness around the cutter edge. It has the outline of the cutter to let me position it under the cutter when tracing the thickness contour.

    the two near circle lines let me draw a contour around my scraper.

    73240562-0B3F-45CD-A3D3-D8FBD2B42D32.jpeg
     
  32. hockenbery

    hockenbery AAW Advisor Staff Member

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    Okay got it. Yes the 3/4 stabilizer can hold any 3/4” diameter tool shaft. And with adapters other diameters.
     
  33. Roger Wiegand

    Roger Wiegand

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    Doh! (what more can I say). What an elegant answer.

    It does require a method to rigidly attach the camera to the tool so that the geometry remains constant. I had been imagining a system that would work from a fixed overhead camera not tied to the tool. Perhaps still some room for invention there!
     
  34. hockenbery

    hockenbery AAW Advisor Staff Member

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    attaching the camera does require mounting on the tool assembly which pretty much means a Jamieson system or one of the articulated systems like the Bosch stabilizer or the Simon Hope. I use both the Jamieson and the Hope.

    Soon after Trent began marketing his visualizer, some company came out with a fixed camera for spindle turners.
    An image of the desired object was overlayed on the blank. Didn’t catch on since most spindle turners have quicker and more effective low tech methods.
     
  35. William Rogers

    William Rogers

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    Michael, yes you can use the Jamison bar in the Stabilizer. However there are many ways to do the shape you are referencing. I can set my Simon Hope bar similar to the Jamison bar or use my Trent Bosch extreme bent to get that shape. I even made some homemade bars. I use all of the bars in the picture can be used with my system.

    85346930-1F3A-429C-B808-2D694EFD7511_1_201_a.jpeg F833C56A-E801-4C64-801B-30A8478CC29C_1_201_a.jpeg 0758186A-4986-4856-8ABA-97ADEA3F4AC2_1_201_a.jpeg 7481B0D5-3A16-4CCC-BBB9-C7623BF71CF8_1_201_a.jpeg 52EAF996-100D-4460-BE20-1281C884357C_1_201_a.jpeg
     
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  36. William Rogers

    William Rogers

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    Here is how my camera is mounted. Note that the screen is a small screen that came with the system. I did convert a large 21” monitor to use, but it changed the ratio and was a PIA to drag it out. I went back to my small screen. My ratio with the small screen is close to 1:1, so I don’t even draw the thickness lines.

    C48E2384-E6C8-4CB3-AE8E-25F5095A73EA_1_201_a.jpeg
     
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  37. Chris Edwards

    Chris Edwards

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    I'm getting ready to start doing a little bit of hollowing and after a bit of YouTube research, I set this system up a couple of months ago.

    If you actually watch it on Youtube, I have links, to Amazon, for all the parts used in the Description.

    Now I've just got to bite the bullet and buy the Lyle Jamieson setup.

     
  38. Michael Nathal

    Michael Nathal

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    I do have a bent tool similar to the ones you are showing. Note that one end of the Jamieson bar looks the same as the Simon Hope tool you show: a straight shaft with the hole for the pivoting head parallel to the shaft. But the other end has the hole drilled at 45 degrees thus allowing a farther reach. I am looking at one of my pieces, 12 inch diameter, 3.5 inch high: with a 2 inch entry hole, both the bent bar and the Jamieson can reach the 12 inch diameter. But the Jamieson bar can reach the same diameter through a much smaller hole, about 1 inch. (Correct me if I am wrong.)

    What I am curious about is that the Jamieson bar with the pivoting head in the 45 degree position will have the potential for a lot of torque placed on it, compared to a bent bar. In the Jamieson system, the D-shaped handle seems to counteract the torque nicely. But if you use the same Jamieson/45 degree bar in the Bosch system, it seems you are relying on a single set screw to resist the torque.
     
  39. Doug Freeman

    Doug Freeman

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    Lebanon, Missouri
    Cant comment on the Hope setup, but with the 3/4” jamieson bar I use a 1” to 1–1/8” hole to get out to the dia you describe.

    As for torque arresting your assessment is correct, and comparison is easy. Measure from the bar CL to the cutting edge, perpendicular to the bar CL, for the 2 setups. The ratio of the 2 #’s is the applied torque difference. If the jamieson is 2” and the other is 1”, the jamieson will create 2x the torque for the same cutting load.

    The jamieson D handle uses a set screw to transfer torque from the bar to the D handle. If the other set up has the same size and design of the set screw (cup point) it will hold the same amount of torque.

    FYI. I have had the set screw come loose when getting into a chatter situation.
     
  40. William Rogers

    William Rogers

    Joined:
    Mar 19, 2016
    Messages:
    646
    Location (City & State):
    Haubstadt, Indiana
    Michael, The hope system has a cutter where you can put it on the Hope straight tool and rotate it to any angle, not just 45 degrees. It will function the same as the Jamison with the cutter at 45 degrees in a straight bar. As far as counter acting torque, articulate arm systems are different. The Hope system uses an I” (may be larger) post the arm fits over to counter act the torque where the Jamison is captured. Would be hard to say which is “better”, but both work well.


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