Rotary Jig Prototype II revisit.

[cestout]

I am finally getting a round tuit. I have it all carved (except the knobs - I will make my own on the CarveWright) but I have hardware questions. I the previous thread people said the they ordered the roller and bearings. What exactly am I looking for and also the two bearings for the dowel? And what is the purpose or the lift lever? A spring goes under the roller lift, I understand that part, but are there any other spring needed? How are the slide plates held in place? I see a screw with washer holds the left one from falling out, and I assume the pressure from the dowel holds the left one, but what holds them from moving up and down?
Thanks

[bergerud]

The bearings are standard 1/4" inside, 5/8" outside and are for the dowel pins to turn in. One could use bushings.
The lift lever compresses the spring to lift the dowel of off the rail. This is only to help in set up so that it is easy to roll the dowel or slide the rail. Otherwise the rail is pinned between the dowel and the sandpaper belts.
There are three springs. There is a spring under the roller lifter. This spring has to be fine tuned to balance the CW roller spring so that when the jig is clamped down, the CW roller switch just clicks. That way to CW roller is easy to push up by the roller bearing (a router bit bearing) on the bottom of the roller lifter. Another spring is in the right side slide plate and is only meant to stop any back lash when using the screw to make the dowel level. The main spring is the spring under the left slide plate which pinches the rail between the dowel and the sand paper belts.
The left slide plate was going to have a small retaining metal plate, (See the screw hole and the machined recesses?) but it did no seem to need it. It is held on the bottom by the bolt through to the lift lever. The right side is held in place by the screw (with the spring on it) used to adjust the vertical height.
The left slide plate moves up and down but is pushed down by the spring and that is how the rail is pinched between the dowel and the sand paper belts. (The rollers of the CW hold the jig in place but do not put pressure on the dowel and rail.) The right slide plate remains in a fixed position by the vertical adjusting screw. The only reason it slides is for initial "tuning" to make the dowel horizontal.



I hope this helps. I am sorry but this was only a proof of concept prototype and I was working on a list of improvements.

[cestout]

Thanks, that answers all the questions that I know I have currently. I am sure that I will have more that I will probably have to figure out for my self. If I can't, I will be back. I am collecting all the notes from your posts along with pictures of each part from a designer scree shot (also showing the board size), and the pictures you have had in your posts, into one document (MSPublisher but can be printed to PDF).

[cestout]

Being a bit frugal (euphemism for cheep) I made my own knobs, and they fit in my wine stopper sled (holds 3'x 6" pieces and 3" x 3" glued end to end work). You press a T nut inside the smaller piece and glue them together cross grain.

[bergerud]

On my last rotary jig carve, I noticed that since upgrading to the rubber belts, the jig sits a little higher on the keypad side. With the rubber belts, the squaring plate was raised with shim washers and that raises that side of the jig. The jig was designed for the sand paper belts and so, if you have rubber belts, you might want to trim that shim width off of the bottom of the left side of the jig.

[cestout]

I finally got it tweaked and working. I had to put a piece of black tape over the keyboard end axel because the board sensor was getting confused by the low instead of no reading. I thought it wood and it did carve mirror image. The carve moves toward the front instead of the back. Note to those who build this, the spring that holds the piece down on the rail has to be quite strong. Do you think I should take it to the Woodworking show in November with my other samples, or would it be too much for the potential users to grasp?

[James RS]

Nice, I am thinking on building this also

[bergerud]

Nicely done. It makes me very happy to see you have it working.

Why not take it to a wood show. Something for people to think about! On the other hand, it may just be something you have to keep explaining!

I think the spring could be weaker if one put a rubber strip on the bottom of the rail. (I assume the slipping was between the rail and the sandpaper belts and not between the sandpaper and the dowel.)

[cestout]

Slipping was the spindle to the rail. I have rubber belts on both machines. Fyi, I bought a box of assorted spring for under $5 at Home Depot. The bearings were from my router bit parts drawer. I glued up some 4 quarter poplar and turned it on my lathe to get the spindle.

[bergerud]

I put a strip of anti skid sandpaper tape on the rail top and was amazed at the grip on the dowel. I originally had sandpaper belts and that was where mine slipped. Now I have rubber as well.

[Russel]

I have been silent for several weeks about the rotary jig II that I built. Previously, a problem occurred when I tried to initiate a carve operation. I never was able to have the board edge sensor give an acceptable reading. After letting the problem sit for some time, I tried to adjust the sliding plate. Now, I get a board sensor reading of 162, which is good. However, when I attempt to initiate the carve, I still get the message to check the board sensor. What am I missing? Has anyone else built one and seen this problem? If so, what is the solution? The jig positioning is correct.

It looks like I need to read a little further down, before commenting.

[bergerud]

The problem is probability to do with when the rail lets the back roller drop. The way I start is to move the rail back until the back roller just clicks up. To the machine this is the same as the roller being just on the edge of the board. The roller will drop as soon as the x moves. Now put a piece of black tape in the middle of the dowel about an inch (along the circumference) away from the sensor.

When the x starts to move, the roller will drop and the tape on the front will roll up to the sensor. The machine will think the high-low reading from the tape is the back edge of the board.

It may be that you have to tweak the rail - roller lifter setup so that the roller switch just clicks up when the rail is back. I mark the rail with a pencil so I know just when the roller is up.