Setting Platform for a Desired Bevel Angle

[Don Stephan]

While I haven't tried anything yet, I'm looking for ideas for setting a platform close to, not necessarily to the nearest tenth of a degree, to a desired grinding angle. My idea is to cut the corners of some small plywood pieces to particular angles on my miter saw, and adjust the platform so the corner with the desired angle touches the grinding wheel perhaps 3/16" above the platform surface. I use all the common high speed steel spindle and bowl turning tools. Thanks in advance.

 

[Don Wattenhofer]

I think there has been a thread recently that addressed that point.
For me I just made some extra platforms and permanently set them for the angles I use.

 

[Ron Solfest]

As @Don Wattenhofer said, there were just a few comments on an old thread within the last week or so. I wish I could find it to give proper credit to someone that put a fair amount of thought and geometry into the solution that I copied in the pic. A couple days ago I made three of these simple jigs to give me quick platform align for scrapers, negative rake scrapers, and a 40/40 grind. Simple, and work efficiently, they hang just below my grinder now. I wish I could remember who to give the credit to for this, and provide a link to the thread for the thought process…thanks

 

[Dean Center]

You can change the nose angle of your tool by raising the height of the platform. For example, if you add a 1/2" thick piece of wood, your tool will contact the wheel substantially higher, which produces a more acute angle.

It turns out that we really don't have to have many angles to suit different tools--maybe 55-60 degrees, 35-40 degrees, and 20 degrees or so for us skew users. I made several of these "shims" with magnets glued to the bottom so they would be secure but also easily removed. They worked OK. The main issues I found were the drag on the tools from the wood surface, and increased wobble from the greater height above where the platform was attached to the base.

Then I got a Robo platform which allows me to instantly switch from one angle to another, and I never used the wood platforms again. That rest is no longer in production but someone is making and selling a different but comparable version.

None of these are precision tools. You can't make them be 60 degrees rather than 58.5. A well made platform will be consistently 58.5, so your sharpening will be reproducible, but they won't make NASA happy.

 

[Doug Freeman]

I made these jigs to reset a platform to a desired angle. They will work with any platform or wheel. Used an angle gage and a scraper to get the platform to the desired bevel angle by trial and error, then pushed the end of the plastic into the wheel. Used a dremel to relieve the center part of the resulting curve. Bevel angle changes a bit depending on the steel thickness, which is no problem for me, and are very repeatable. Also very cheap to make.

 

[Mike Selser]

As @Don Wattenhofer said, there were just a few comments on an old thread within the last week or so. I wish I could find it to give proper credit to someone that put a fair amount of thought and geometry into the solution that I copied in the pic. A couple days ago I made three of these simple jigs to give me quick platform align for scrapers, negative rake scrapers, and a 40/40 grind. Simple, and work efficiently, they hang just below my grinder now. I wish I could remember who to give the credit to for this, and provide a link to the thread for the thought process…thanks

I believe you are referring to posts by Paul Rudd

 

[John K Jordan]

I don't remember the thread referenced.

Years ago I made angle-setting jigs from small scraps of Plexiglas to quickly set the platform to the precisely for skews, scrapers, hand scrapers, and other tools. I use one or both ends of a piece of plastic, making sure the long sides are straight (don't have to be parallel!)

I made this one to set the platform to the angle I use for my curved negative rake scrapers, here standing on edge to show the included angle.



My method of making these:

• Set the platform as desired for a particular grind. Turn the grinder off!
• Hold a straight edge of a piece of plastic on the platform and position it a little past and hold firmly against the side of the grinding wheel.
• Trace the curve of the wheel on the plastic with an extra fine sharpie pen.
• Cut the approximate curve on the plastic with the bandsaw, just outside the traced line. Note: when sawing clear plastic the thin traced line is hard to see. I first taped down a piece of thin white card stock in middle of the bandsaw table.
• Cut out a bit of relief in the center of the curve with a couple of bandsaw cuts to leave just two short contact areas. Smooth the relief cut with a file or something if desired.
• Turn the grinder on. Hold the straight edge of the plastic firmly on the tool rest and push the bandsawn curve lightly against the spinning wheel to grind the two contact points to the exact curve and smooth the rough bandsaw cuts. If the bandsaw cuts are reasonably close to the sharpie line and the relief cut is large enough it takes just a second to smooth the curve. The heat from the wheel may soften the edges of the plastic and squish out a tiny bit - break or cut off with a knife and sand the edge smooth if needed.
• Spray the back side of the plastic with white paint. Write the angle and purpose on the plastic.

These make it very quick to set the exact angle. When using, I hold the thing against the tool rest, fairly perpendicular to the face of the wheel, and adjust and lock the tool rest angle. Thicker Plexiglas, say 1/4" or so might be better. These things could be made from aluminum as well, easily cut on a shop bandsaw. (As always, be careful to press thin material firmly against the table while cutting.)

Below are the first few I made from Plexiglas scraps, quick, easy, and precise. There is plenty of space on some of these for more angles. (The edge of the scrap plastic can be flattened against a large flat file or a piece of sandpaper held on a flat surface.)

Here I'm using the 90-deg one to set the platform to grind a hand scraper (before I thought of painting the back side white!)
Painted white, as shown in the photo above, was a big improvement!


JKJ

 

[Mike Novak]

Here is a link to Paul’s thread

Thread 'Video for "Simple Jigs for Setting Angles with the Oneway Wolverine"'

Sep 8, 2024

I made a YouTube video to go along with my original post.

View: https://www.youtube.com/watch?v=PYNx5Wtr_v0

• Paul Ruud
• Replies: 38
• Forum: Tutorials and Tips

• 

Much easier to use than the ones Doug and JKJ showed above. Easier to make also, especially if you aren’t concerned about exact angles. But will only work with CBN wheels with guard removed.

 

[Dave Landers]

These are the ones I made (and how I made them)

 

[Kent Reisdorph]

Has anyone tried using their phone to set the angles? There are lots of free angle apps.

 

[Doug Freeman]

Has anyone tried using their phone to set the angles? There are lots of free angle apps.

There might be a way, but I’m not aware of any. There is not a way to reference the phone to the wheel, only the platform.

The issue is that the platform must be set to the wheel. A platform can be at different heights with respect to the center of the wheel, which requires the platform to be at a different angle with respect to horizontal to grind a given angle. The distance the platform is from the wheel also effects the ground angle, due to touching the wheel in a different spot.

 

[robo hippy]

Well, I cheat and use a platform with pre set angles so no guess work is required. I do wish some one would "new and improve" my old robo rest. Woodpeckers has a drill press mini table with 1 degree increments and a cam lock on the other side. That would be a good improvement. I talked to them about it and they said "maybe".... I think 5 degree increments would suffice for 99% of the turners out there. I do not use jigs....

robo hippy

 

[John K Jordan]

I do wish some one would "new and improve" my old robo rest.

I saw one on a grinder at the TAW, hadn't seen it before up close. I did think of some things I might do differently if I made one for myself but can't remember now - I should have taken some photos! Maybe I can find one locally and take a closer look.

I suspect anything I did would make it too expensive to sell, but that's not on my radar. At 75 the last thing I need is a JOB!

JKJ

 

[robo hippy]

There is a "Right Angle" platform, and I do have them, but all of my angles are set up for my platform. Mike Waldt did a video about them and they work fine with repeatable angles. The price range is in the $180 to $220, if I remember correctly, but that is sketchy.... One used a lever under the platform table and a number of holes that the tail end could be stuck in. The other was 6 or so double nut screws so you could set your own preferred angles and go from there. There were free standing and Oneway compatible models. Considering how the metal prices have gone up in the last few years, I would expect the ones I used to make would be in that range now.

robo hippy

 

[Michael Brown]

I have the woodturners wonders indexed rests. I created two shims that sit on those when they are set to 40 deg, so I can handle 20 and 25 deg for scrapers/skews. I almost never have to adjust the rests just set the shim on the rest and touch up, then back to 40 deg for essentially everything else I sharpen.

 

[Bob Raasch]

Michael, I'm curious bout your adaptation as I have the Woodturners Wonders indexed rest also, used with the Kodiac Max system.

 

[john lucas]

I improved my Kodiak rest. I got tge idea from my Ribbo rest. I added index holes every 5 degrees that were not already indexed. Well I don't know why the photo is not coming up.

 

[Michael Brown]

Michael, I'm curious bout your adaptation as I have the Woodturners Wonders indexed rest also, used with the Kodiac Max system.

Here is the insert/shim thing