I still like the idea, and thought I would share what I did so far. To maybe be completed at a later date. First, here is a pic of the inspiration from FLW.

I sliced and sanded several species to a thickness to about an eighth of an inch. The gridwork is out of strips of walnut. Other woods are maple, Spanish cedar, purple heart, wenge, and cherry. The concept was to glue all the pieces to a sheet of Baltic birch and thickness sand it smooth. Then cut the female circles with a router into the glue-up and turn the male circle inlays on the lathe faceplate. Glue it again, surface sand again, and add the sides.

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Oh well, things happen, and dreams get placed on hold. At least I finally get the excuse to get a new saw.

Good luck to all the other entries,
Steve

There is a story behind the walnut endcap. It is from the Buck Hill ski resort in Minnesota, south of Minneapolis. I grew up across the street in Northfield from the woman who owned Buck Hill before it became a resort. In 1954 before she released it, she cut down some of the walnut trees, had them sliced up and stored them in her garage attic. When she passed away in the 70’s my Dad and I helped clean up her place and found a couple hundred board feet of it. My children’s crib and toy boxes are also made from it.

I made a handle for the front vise from an oak dowel and some cherry rings cut with a forstner bit and a hole saw on the drill press. Not sure I like it, but it works for now. Any suggestions?

So now I need to drill the dog holes. Any help on this? Should I run a double row for each vise, or what? Should I change the endvise’s chop to be wider and cover the entire width of the bench? If I run a double row for the endvise, it would put holes right down the middle of the bench.

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Thanks for looking,
Steve

I was working alone on the top, so I was unable to do the “glue up three and send a batch through the planer technique”. I just kept gluing one 4×4 to the next, waiting a half hour, and continuing. The only way to smooth it at the end was with a hand plane. It went way better than expected, probably because the plane arrived pre-sharpened.

I was just playing around with the face boards and clicked a pic. That is maple for the front and walnut for the end cap. I believe they will be trimmed to about 5 inches in width.

Making a mess using a router for the tongue for the end cap. Clamped a straight edge and routed from the top, flipped it over and repeated for the bottom side.

The new top after some clean up.

Take care,
Steve

I will give the top pieces a final jointing before the big glue up. I am dreading this glue up. I have not decided if I will try to do it in sections and then either thickness sand or thickness plane as I go, or just go for it. This stuff is gosh darn heavy. Maybe I need to grow up and hand plane it.

The plan is to add a 4/4 maple front and use 8/4 walnut for the end plates (because I have some of both) before I attach the vises. Bench dog holes will be drilled after it is all together. I also have a little 8/4 maple for the vise chops.

I am trying to keep the cost under $200.

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The 6 foot 8/4 for the top. Cut, jointed, and milled to thickness.

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The stretchers cut with tenons. These were resawed from 8/4. They are waiting for holes for the draw bore tenons, and for a bit of edge treatment.

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The two towers. Pretty much completed. Mortised and drilled for the stretchers. I cut the large mortises for the uprights with my CNC. That was fun. I cut the mortises for the stretchers with a hand held router, just because.

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The two vises purchased from Grizzly. Can’t beat the price. I hope they work out OK.

Comments or suggestions are very welcome.
Steve

“The Low Angle Smoothing Plane is based on the rare Stanley 164, and is essentially a shorter version of the Low Angle Jack Plane — with an adjustable mouth, and a massive 2” (5.08cm) wide, 3/16” (4.7mm) thick blade, set at 12°. However, this tool is only 9½” (24.1cm) long and weighs 3¾ lbs.

We call it a Smoothing Plane because of its size (the same as our No. 4 Smoother). But like the Jack, it excels at both rough and finish work, and can be converted from one mode to another very quickly. The unique overhead Bailey-type blade adjuster provides smooth depth adjustment at your fingertips.”

Here are some pics of the place:

Here are some returned planes being restored:

And here is their company store complete with wood and benches that allow you to try before you buy:

I am one happy jock. I’ll post a review once I have played with it some more.
Steve

I thought this would be a good time to explain some of the things that need to be decided, even for something this simple. Unlike hand routing, you actually have to state how fast and how deep to plunge, what the step-over or overlap is, and whether to climb or conventional cut.

So I chose: 1 inch per second feed rate, 1/2 inch per second plunge rate, 1/3 inch plunge per pass, 2 inch final depth, 40% step-over, and conventional. So routing a 2”x2.5”x2” mortise takes about 2.5 minutes each. I could push it faster, but it is actually removing quite a bit of wood even at this rate.

This is called Pocket routing, as opposed to Raster (carving), VCarve (signs), or Profile (cutting out) routing. I took off the dust skirt so you could see it work and hand held the vacuum.

Steve

I am trying to figure out how to complete it. The door is not attached. It is about an eighth of an inch thick. The plan was to glue a block to the inside top and bottom of the door and use finishing nails as hinge pins. The door was also supposed to have long iris type leaves jig sawn into it, but that is not going to happen. In fact, the door may just turn into a shelf do to time. In fact, it looks pretty good with out the door, and a shelf would be cool. Any suggestions?

So off to a final sanding, figure out the door/shelf dilemma, and then a few coats of oil.

Good to be back in the shop,
Steve

Jointed and resawed a bit. Then I sent them through my little Ryobi thickness planer. Even after letting it acclimate to the house for a week, once it was prepared, it still warped more than I would have thought. I had never resawed anything before as all I have is a craftsman bandsaw. But with a new large blade, it worked much nicer than I would have thought. You can see the bandsaw in the background.

I had never really used sliding dovetails for joints. They really lock into position. I like ‘em. I cut them with a little sliding jig on the router table. I thought that I better not use the CNC, as that might be a no-no for this contest.

I won’t be able to get any more done for a while as I ‘have to’ go spend next week in the Caribbean and escape winter.

Steve

I needed to address some of the problems that I noticed from before. Complexity needed to be reduced. Some of the racking and shifting needed to be addressed. I wanted to remove the concept of keeping all the skate bearings so tightly pressed against the rails. And it needed a face lift. So I came up with a new (is anything new?) design.

I kept the leadscrew and motor combination along with the torsion boxes. I got rid of the box below the gantry to let the bed lay flat on the table top. The sides were to lose the stiffeners by using a different strengthening technique. The wrap-around Y carriage was to turn into a flat plate. And I went with V-bearings for the linear rails. These bearings are actually fancier than they look. They have two rows of ball-bearings to be able to take both lateral and radial pressure.

They were to ride on angle iron as the official V-rails were beyond my pocket book.

I spent a fair amount of time trying to find a way to make the gantry wall stronger. I actually tested various plys and MDF combinations. I found out that 3/4 inch MDF skinned with laminate on both sides yielded a very strong panel. I also found that yellow glue was better than contact cement at holding it all tight. This combination actually makes a small torsion box, which is a substrate tightly coupled to skins on both sides. I edge banded them in maple to keep out moisture.

My gantry now looked like this:

I went with dual motors on the long axis to virtually eliminate any racking and more tightly couple the drive mechanism to the bearings. I used wooden standoffs to attach the motors.

The leadscrews where coupled to the anti-backlash nuts with wooden holders on each side of the gantry.

I attached the Y leadscrew to the carriage underneath the Y torsion box to get it out of the way.

I used the removable Z from the last machine and mounted it on this one.

And then added dust collection. A must needed addition.

It was all working pretty darn alright. But there were a few things that I decided to upgrade. The V-bearings for the Y carriage were digging into the edge of the angle iron. I solved this by adding a few wooden strips and mounted the angle iron with the angle facing up. This vastly improved its ride. I had also noticed that sometimes the steel rods and brass bushings for the Z were sticking, so I switched them over to V-bearings as well.

And finally I cut the plate across the front of the machine and added an end vise for vertical board routing.

To those who are still hanging in there: On a different note, before I had the money to buy a CAM program, I needed something to use for test cutting. So I wrote SpiroCNC. I think alcohol was also involved. It would generate G-code for spirographs and other geometric designs. It was kind of stupid fun and is still used a bit by people in that same situation. I did also use it to generate some rosettes.

Take care,
Steve

Do you need one? No.
Should you build one? Probably not.
Have I done anything useful with it? Not really.
Is it cool? Oh yeah.

In 2004 I stumbled on an Internet advertisement marketing a book “Make your own CNC”. I did not realize this was possible. It got me googling and I found a free set of plans call JGRO and a bunch of guys building them. I ordered some stepper motors and a controller board kit, and hit Home Depot. This is what resulted.

This is called a gantry style machine because of the overhead structure, as compared to a moving table type machine. It is a three axis machine, X is the long one that the gantry moves along, Y is going across the gantry, and Z is up and down. It uses roller skate bearings running on black gas pipe. These bearings were mounted in aluminum angle to form a V. The pipes were suspended with adjustable bolts at the ends. It used threaded rod for the leadscrews and homemade leadnuts made out of delrin plastic. I built it in one mammoth weekend.

I bought Mach3 (it was really Mach2 back then) as the controller software to take XYZ commands called G-code and turn them into step and direction pulses. I cobbled up an old PC and dedicated it to this purpose.

You can see the picture of what is being cut; a new router holder for the Porter Cable laminate trimmer.

Machine #1 was terrible, but I was one proud puppy. The machine flexed like crazy, it was amazing how much gas pipe will flex over a four foot unsupported span. It was incredibly slow and the leadscrew whipped like a jump rope. The backlash, or the amount of slop in reversing directions, was unacceptable.

This was quite early in the home CNC game and I could not find much on the subject, so I decided to attack each of these problems; flex, whip, speed, and backlash and come up with my own solutions. Enter the prototype for machine #2.

First attack the flex. The pipes had to be supported and some better construction techniques used. I turned the machine inside out, and supported the pipes with torsion boxes.

I used machine #1 to cut some struts for the Y torsion box.

I needed a way to keep the bearings riding on the pipe. So I came up with an adjustable plate that would press the bearings against the pipe by tightening screws captured with T-nuts to move the plate.

The assembled gantry with the Y carriage:

I added the same adjustable plate assembly to the inside of the gantry to ride on the X axis.

I mounted the gantry and the X pipes and checked for a smooth ride and that everything was parallel. A huge success. I could skim the clamped ruler to every corner of the table without an issue.

Now for some stress testing. To just add all kinds of weight I found a rather large motor and clamped it to the Y carriage, then repeated the skim testing.

It bound up. By adjusting the pressure plate on the bottom of the gantry, I was able to bring it all back to parallel and complete my testing. Yeah!

But the gantry was under a lot of pressure and the walls were bowing outwards. I would add stiffeners to the gantry walls later and pull them back vertical. The plate assembly was buckling a bit. It kind of wanted to rip itself apart, but it held. All in all, life was good.

So on to the Y carriage. I had noticed that it was falling apart with my stress testing. I needed the carriage to wrap around the Y beam and still be strong. I made several attempts at it and came up with gluing thin plywood to the sides of the structure and then using a laminate trimming bit to route out the inside, leaving a one piece skin. Strong.

And back to stress testing the new carriage. Success. Note the consistent vertical gap between the carriage and the beam. Yeah.

Now on to the Z axis. I chose to make it removable so I could play with it if needed. CNC guys love to play with their Z. I used polished steel rods with bronze bearings for the vertical rails to make the Z more compact and keep the router from cantilevering out too far. The picture is looking inside the Z from the back as it laying down. The two small blocks of wood have the bronze bearings in them, these are also attached to the face plate and the lead nut. So they go up and down.

I need to point out here what I did for leadscrews. Three problems need to be addressed; speed of the machine, the whip of the screw, and backlash. Backlash is a bad thing that occurs when you reverse the direction of the motors, which happens a lot. The leadnut must not have any slop in it or bind. I solved this by buying, you guessed it, anti-backlash nuts. They show up in several of these pictures. It is a plastic nut with a flange for mounting. They have slots cut in them, a spring, and a collar that form a very tight nut with just the right resistance.

To get the speed of the machine up, and the whip down, I went with fewer turns per inch on the leadscrews. Fewer rpms for the screws mean less whipping while kicking up the machine speed. This is a little harder than it sounds. These are ACME double start screws, which actually have two sets of threads. They are 8 tpi, but since the are two start, for every 4 turns of the screw the leadnut moves one inch. Why not just buy 4 tpi screws? Cause they don’t make them. Since you want about 6 to 8 threads for a nut to grab on to it would make the nut really long and unstable.

The next problem for the leadscrews in the hobby arena back then was mounting them and attaching them to the motors. What you want to do is ‘fix’ them to the frame of the router. A screw can spin upwards of 5 times faster without whipping if it is ‘fixed’ instead of just spinning in a bearing. The big boys have all kinds of tricks they do with turning down the ends of the screws, but I don’t have a metal lathe. So I mimicked their set up and came up with a method of using two bearings pressed into recesses either side of a plate that is firmly attached to the frame. Next on each side is a spacer and then locking collars. Then come Love-Joy motor couplers that have a piece of hard rubber in the center to allow a slight misalignment to affect things. These couplers also allow a transition from 1/2” screw to 1/4” motor shaft. This is then attached to the firmly self-supported motor. This is what those motor ‘towers’ are all about. Whew.

So here is Machine #2. Note the stiffeners glued to the gantry walls.

She then had the job of cutting out some larger router mounts.

For her big brother.

So how did it work? Not bad, not bad at all. A pretty tight machine. There are some things that I just wasn’t happy with. The gantry could rack or twist. I could hold the left side and push and pull the right side and it would move. The Y carriage could tilt backwards a little bit if I drove the router down quickly (I know, don’t do that). The whole machine was held together with tension and that just seemed wrong to me. It used radial skate bearings at a 45 degree angle and that also just seemed wrong. And my version was butt ugly.

I was posting this on another blog as I built it and quite a few people were watching and helping. Actually this has become a very popular design with at least two people selling kits of pretty similar machines. They will give the plans out for free. There are users groups now. It makes a Daddy proud. Here are CAD renderings of their kits. Google these names if you want to persue. See if you can spot any similarities.

LionClaw’s

JoesCNCmodel2006’s

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Next post, machine # 3
Steve