The Universal Carrier Base

[ktjwilliams]

Intersting , very interesting ..... I still have to build mine, been very busy with some home remodeling ....

[Rocketman]

I figured the only time the board was being measured was at the beginning of the job. If that's true I could jog to a cut in my carrier rail and let it measure the board there. It seems to track down the center of the board to measure the length in which case I would not need to lower the entire side. As far as different length boards go; I could put several slots on a longer carrier similar to what you did with your touch holes. As far as setting it up slightly below the rails, it would still work as long as you jogged to the board for touch off. I think you said somewhere there can't be a height difference more than 1/4" so if we stay within the bounds it should work. Now if it's measuring board length down the edge of the board my ideas have no merit.

[bergerud]

There is a connection between the rollers dropping and the board sensor. The board sensor only looks for the board edge after a roller has dropped. It knows about where to find the board edge based on where the roller dropped. (Jogging has nothing to do with it.) The rollers have to drop where the edge of the board is or the machine will give an edge detection error.

I may not understand what you are suggesting, but what you are thinking must take the roller - board sensor relationship into account.

It is possible to to have the machine only locate the back end of the board if one uses place on end instead of place on center. In this case, the machine does not even look for the front edge of the board. (I used this with my early rotary jig. I had a rear roller lifter which dropped to fool the machine into thinking there was a rear board edge. Then a piece of black tape on the dowel fooled the board sensor into thinking it detected the rear board edge.) I think that same basic idea would work. You would place the board in the carrier so the back edge lined up with your slot in the side. You could do this for different length boards as the it does not matter where the front edge of the board is.

[Rocketman]

I think what your suggesting is a slot in both sides of the carrier at the end of the board so the roller does in fact drop? I do like that idea even more! Place on end works to use even less material out of given board. Sometimes my boards are longer than my project but not quite long enough to fall in the 7" limit. Placing on end would give me a few inches I may or may not be able to use for gluing up in laminate pattern work later.

I've found setting the rails by measuring down 1/8" less than my board thickness with an adjustable square is easier than trying to hold an 1/8" shim and tighten things at the same time. I really like the idea of setting it flush or slightly below to simplify setup and get rid of the shims all together.

The Rube Goldberg way of fixing it would be to add a small stereo ear phone jack in series to the roller switch so that when an ear phone jack is plugged into it, it would break the connection. The inserted ear phone jack would be hooked to a small lever switch mounted on the top of the carrier and would become active in place of the roller switch when plugged in. The switch would be tripped by a feeler mounted on the machine so that at the appropriate spot 3-1/2" from the end of the carrier, it would activate and fool the machine into thinking the roller had dropped and turn on the board sensor. To make it even more absurd, rather than have it wireless, have a series of cable routers with small retractable pulleys hanging on the thing to keep the carrier switch cable from getting caught in the carrier and track rollers as they move back and forth.

I'm still going to give some thought of a more practical way of fooling the roller drop sensor to trip the board measuring sensor. I've got plenty of optical sensors, magnetic sensors, limit switches, lever switches and more at my disposal to figure out a way to take the roller out of the equation. It's not a big deal but it does bug me.

That extra servo motor I now have on hand may be used in a future project rotary jig project. While you and Baker have come up with some clever solutions to fool the machine, my idea is to take part of that ear phone jack idea and incorporate it into a method to disable the X drive. I'm thinking of building a rotary jig with it's own servo drive motor. I'd need to gear it so it's the same travel rate as the original X to make programming easier. Rather than and ear phone jack I'd need enough connection points to provide the power and quad encoder connections. I'm thinking of soldering it up so that by removing one plug I can disable the X axis and then move my rotary jig in place and plug it in where the original X connects. The signals sent to the X axis would now go to the the rotary jig. As a bonus I could wire in the Y axis with a plug also. Then if I wanted to turn something longer I could make a long rotary jig and place it on the table like we do a board. The servo would get plugged into the Y axis in this configuration and the X axis would move the jig under the now stationary cutter. I might need to make a clamp to hold the Y axis from moving when disabled from power but that would be simple enough.

The above idea is not mine. Back in the early 80's we had a commercial Tree brand CNC mill. This thing was about the size and shape of a Bridgeport mill and ran mostly in an X, Y and Z configuration. The clever thing about it was it came with a rotary axis that could be bolted to the table. It was designed so you could take the huge motor off the X or Y drive and mount it to the rotary table. You then coded any rotary motion using either X or Y depending on which axis you stole the motor off. It had a key punch typewriter machine that you used to program with. Any changes in a program involved punching a new tape. If you needed many of something it worked great but in today's world where the orders are for one of these and two of those it would never make you money with all the setup time and program time you would have invested.

[bergerud]

I've found setting the rails by measuring down 1/8" less than my board thickness with an adjustable square is easier than trying to hold an 1/8" shim and tighten things at the same time. I really like the idea of setting it flush or slightly below to simplify setup and get rid of the shims all together.

Have you seen the pop up rails that I use?

http://forum.carvewright.com/showthr...999#post248999
http://forum.carvewright.com/showthr...293#post249293

If only one could come up with a simpler design for them. They make the carrier more versatile and easier to use. I had hoped to incorporate these or something like these in plans for a better carrier base.

(Now you have me thinking again. Maybe I will play with the place on end idea.)

[Rocketman]

Have you seen the pop up rails that I use?

http://forum.carvewright.com/showthr...999#post248999
http://forum.carvewright.com/showthr...293#post249293

If only one could come up with a simpler design for them. They make the carrier more versatile and easier to use. I had hoped to incorporate these or something like these in plans for a better carrier base.

(Now you have me thinking again. Maybe I will play with the place on end idea.)

Yes I seen your rails. Very clever! That's kind of why I slid in the Rube Goldberg reference, I figured you could relate to overbuilding something and making it complex just to accomplish a simple task.

I was just thinking about your rails last night. The answer I came up with is to make the rail slots as a zig-zag pattern with each motion from side to side allowing the rail to move up or down in 1/8" or maybe 1/4" increments. The rails would be easy to adjust in increments and the angle of the zig-zags would help to hold the rails in place while locking them down. With most conventional lumber in even sizes this might work. Odd sized lumber or stuff I run through the planer for example would need fine tuning to get it to work with the zig-zags. This could be done by having thumb screws on the rails. When the screws are all the way down it would be for normal lumber. You could adjust the thumb screws up for odd sized boards and even set them independently for odd tapered lumber for example.

What do you think? Would it work?

Brad

[bergerud]

The main problem with the pop up rails is friction. They have to drop while under head pressure. I could not get the inclined plane idea to work because of friction.

[Rocketman]

So much for my zig-zag idea. I was thinking since it would always be a downward slope that the head pressure might even help it down to the next position. I guess I'm back to adding additional complexity to make it slide up and down.

Reduce friction by making the sides out of plastic? We have plastic boards reasonable priced here in Iowa. They are made out of recycled milk cartons. Many of the farmers like to install them as rub zones inside their barns to prevent hogs and cattle from rubbing holes in their barns. You can cut it with a saw, drill it and screw to it just like wood. If nothing else it would make a long lasting carrier. Another impractical idea would be a rack and pinion system like those built into drill presses with a crank on the carrier to move it up and down. That's getting almost as complicated as your "deluxe" rail system but not quite the parts count.

Long story short, I'm sure I'm going to loose sleep over this. It's hard to turn off an active mind with a thread of an idea still present and waiting to be pulled at.

I've always liked your popup rails but I'm hoping I can come up with something a little simpler. So far that seems to be revisiting the "place on end of board" and my slot idea.

I did a two sided carve today and even tried to shim the rollers so I could slide the board out to flip it. With those stop blocks in my carrier it really turned in to a challenge. When I failed at that I went back to the computer and reprogrammed the second side as a separate project. I then flipped my board and started with the second side as a solo project. Things measured properly and it all worked out in the end but I'm still going to hit the hay tonight thinking on this challenge a little more. I'll probably be dreaming of your popup rails and wishing I'd have made me some rather than trying to reinvent the wheel.

[mav36]

I m having a problem also with v groove bit carving too deep. i did the 1/8 height and 2 carving went deep. Did 1 without carrier and it worked fine. any suggestions what I might be doing wrong.

[bergerud]

My first guess would be that you let the bit touch the board before you cranked the head all the way down.