Odie's crazy idea #17

[odie]

With a bowl mounted, it's sometimes difficult to nail the tool height adjustment in relation to the centerline. My usual method is (was!) to make the best guess at the tool rest height, try it, and further adjust to meet my setting.....the ol' "trial and error" method! The only problem with that is if you've guessed wrong, you probably have made a cut on your work piece that you might wish you hadn't!

This block of scrap wood is cut to an exact length to match the centerline of my spindle. It sets on the bedways while you make the adjustment, and it's a snap to get the tool rest height right the first time. No guessing. (both ends of the set-up block must be exactly square) I've drilled a hole and attached a string......the tool rest height set-up block hangs within arm's reach, and easy to come into play.

For this photo, I used a scraper, because it was handy at the time, and it's useful for a gouge as well, although a little less so......but, I've come to really appreciate it for a parting tool.

Position the tool rest in the banjo, and close-in to your work. Adjust it as close as your intuition tells you. Then move the banjo away from your work and adjust the height to perfection with the use of the set-up block. Then move the banjo with the adjusted tool rest back into position. Simple, effective, quick, and a great help for specific applications.

As usual, I expect there will be those that will say something like this isn't needed......and, I've gone without a set-up block for many years myself, and was pretty good at making a best guess.....but, I'm coming to really appreciate the benefits of a perfectly adjusted tool rest height immensely......especially when I get it right the first time!

For most of us, this little dandy will cost nothing!

otis of cologne


edit: In the photo, it appears as if I'm positioning the tool's cutting edge below the centerline. The centerline is the very top edge of the set-up block......I've used a black felt tip marker to make that edge stand out a little more. Although that setting will work to some degree, for a scraper, I'd want it at the centerline, and I probably wasn't paying much attention to that while snapping the photo.......

OOC



.

 

[Turnedoutright]

Alternate idea

Ozzie,
Good idea, I'll have to try it.

When I am looking for repeatable and accurate tool rest height I:

.....put a pre-cut PVC pipe spacer on the tool post. The pvc has a slot in it so that it can be put on and off the shaft without moving the banjo etc.
I have various ones for various tools and tool rests.

Than again I am mostly lazy and just adjust my cutting to account for tool rest height variations.

 

[odie]

.....put a pre-cut PVC pipe spacer on the tool post. The pvc has a slot in it so that it can be put on and off the shaft without moving the banjo etc.
I have various ones for various tools and tool rests.

Howdy Turnedoutright.......(Great handle!)

That sounds like a good idea, too! I wouldn't be surprised if there are other ways of "skinnin' the cat". Woodturners seem to be very creative thinkers.

I had another method, which I've been using for years, and still use......putting notches on the tool post itself to indicate centerline. (I believe this was described in one of my past "Odies crazy ideas".) To a degree, this works too, but not as well as the height block described in this thread. This is because the notch doesn't take into account the thickness of the tool you intend to use......so, ultimately, it does require some amount of guesswork for it to give you an exact height. Your idea of the pvc sleeves to match particular tools would seem to overcome that obstacle. It would seem you might have quite a few pvc sleeves to contend with, though......depending on your tool assortment.

Than again I am mostly lazy and just adjust my cutting to account for tool rest height variations.

I think this is what the majority of woodturners do. The theory with them is "close is good enough". Since there is a certain amount of leeway in the usable cutting area of scrapers used in a traditional mode, and more so with gouges, any height irregularity can be accommodated through simply holding the cutting tool at an angle that suits the needs of the moment.

The height one chooses can be a very personal choice, considering some of us are taller/shorter, have longer/shorter arms, body size, etc......and the height of your spindle itself.

I wouldn't be so brash as to assume my way of doing things is any better than anyone else's, because I only consider MY needs when I do these things........but, in the case of parting tools I do hope a few of you will check this out.......there is a very small area of good cutting with a parting tool. Above the centerline, it tends to not cut cleanly.....and below, it cuts poorly. An exact height of your parting tool edge does best, and guessing at that exact height leaves room for error.

As I said in the original post, I've found that scrapers (used traditionally) and parting tools would benefit most from an exact height adjustment.......less so with gouges.

At the point when I decided I had a need to find the exact centerline without guessing, I pondered the idea of somehow mounting a laser pointer to find the precise centerline on my workpiece. If someone were to actually do that, I suspect it would be the best method overall, and with the least amount of inconvenience. Since the adjustment could be made with the tool rest up to the workpiece and ready for use, I see the added benefits of doing it that way.......I still might do that someday, when I find my round tuit!!!!!!

otis of cologne