Sunday, October 5, 2014

Wooden jointer build

For even basic woodworking, you need flat/true lumber to begin with, for that you need a planer and jointer, either a hand one or powered one. While I really enjoy create shavings after shavings using a hand plane, it's truly time consuming, and have you see the price tags of hand plane nowadays? almost  as expensive as powered ones. The powered tools is also really expensive, especially the wider jointers. With all these excuses, I found Matthias' wonderful plan, and I happened to have a cutter head that retired from a Dewalt 735 by hand, so I bought the plan and start building one.

The goal of my jointer is not build the cheapest jointer possible from scrap, but to build a reasonably sturdy machine and enjoy the process. So I made couple changes to the original plan, not that there's anything wrong with the original plan, no, in fact the plan struck excellent balance between cost and quality. I just feel like it doesn't hurt to over do it, and I do enjoy try out new things ;)

change 1:

I use 1/8 by 1.5 angle iron to brace the jointer frame and support the infeed/outfeed table. The frame, infeed table and outfeed table are made of birch ply, they will provide flatness, but being a relative soft material, it's pretty easy to get dent in the wood. In the original plan, the outfeed table have 4 threaded screw as support leg directly screwed into the wood, if that part of the wood is dented, the table can be out of truth. Also adding the angle iron to the frame means I can secure cutterhead to the angle iron with machine screw rather than screw to the wood frame(This is also Matthias' concern)

change 2:

On the original plan, the infeed table was bolted to the maple rail of the parallelogram, it was kinda awkward to screw on the nuts, I changed it to use a 1/8 by 3/4 steel bar and the angle iron to sandwich the rail and infeed table together.I tapped the angle iron, and use machine screws to secure them together. It's much easier to install the table and the clamping pressure was distributed much evenly across the length of the angle iron.

change 3:

I used two piece of 1/8 by 3/4 steel bar to enforce the cutterhead mount, and it was screwed to the angle iron by four 1/4 machine screws. So basically the cutterhead bearing was surrounded by steels.

change 4:

Use induction motor rather than universal motor. It's pretty obvious, I didn't tear down a planer to get the cutter head, so I don't have a motor from a planer, and they are much louder than a induction motor. I was originally want to use a motor I scavenged from an old hot tub.  But it was too long (the motor body was more than 12 inches long) and the shaft was not keyed, and it was rotating at the wrong direction. Eventually I bought a 1.5 HP motor from harbour freight, it was much compact and not very expensive, and the shaft was keyed.

change 5:

I use 5 rib belt/pulley. they are readily available as they are used on alternators on cars, and you can find any length you want, and they are relatively cheap. In terms of vibration, they are much better than v-belt. I started by using linked v-belt with homemade wooden pulley, as the linked belt is easy to adjust length. But the wood pulley is much wobbly and much likely to fail then aluminium/steel pulley. Although 8 or 10 rib belt system would be better, they are much harder to find and much much more expensive. For the comparison, the belt/pulley I bought is about $7 for the belt and  $15 for the pulley. For the 10 rib system, the pulley is usually in the $60.

change 6:

Double up the linkage. I use 2 layer of 3/4 birch ply to make the linkage arm, figure it would be more sturdy.

Here is the build process:

I start by gluing two piece of birch ply together to make the frame, the ply is not the top quality birch, but still made from 13 layers, I save the best ones for the infeed/outfeed table. I found the best way to make sure the glued up piece is true and flat is to clam straight edge to one side during glue up. I use 2 piece of extruded 8020 alu and 2 level. And of course you need the Long reach clamps :)

The cutterhead mount needs to be snug, so I used a cheap circle cutter. I thought it will be vary shacky, given it's not balanced, but it cut surprisingly clean, almost as clean as my forstner bit. I cut a little smaller than the bearing, and sand to final fit. It was challenge to drill the though hole, as it was almost as deep as my bit can cut. I did it in two passes, the first pass drill to about 2 inch deep, then I chucked the bit a little longer to drill the rest. The most critical part is to drill and tap holes on the angle iron to exactly fit the hole on the mounting block, because steel don't have much tolerance. I did it by clamp the block to the angle iron, then use screw to make some mark on the steel. The tapped hole on the steel is much stronger than just thread on the wood

To mount the motor, it's NEMA standard, so pretty straightforward, I bolt it down on a piece of 3/4 ply and bolt that ply down on the frame. To adjust the belt tension, I tapped 1/4 thread on a strip of maple that I screwed to the frame, so when I tighten the screws, it will push the motor away to tension the belt. Having two screws means I also have control over the pivot of the motor. The piece of steel in between is to provide a wear surface. I don't want anything that protrude out of the frame for belt tensioning, althought it's a bit awkward to adjust the tension, figure I won't do that often.

Here's the video that I spind up the cutter head the first time, very smooth, no vibration, the belt is not even very tight. I'm really satisfied with the result. the nut to lock the pully on the cutter head was not locked in any way, that worries me. I use dremel to cut a slot and clamped a snap ring to it. The pulley on the motor shaft was just keep in place by the shaft key. It was very tight, and the hope is the belt should keep the pully in place.

Next on the list is to make the parallelogram mechanism. I glued two birch ply to make the linkage arm. It is crucial to make the linkage arm to be identical, inspired by this, I screwed couple screw to a ply with the template on it, then use that to mark all four pieces. For the rail, I just use a marking gauge to mark the center of the holes. Because I enforce the rail with angle iron, I marked the holes 3/16 off center.

I cut the openings for the thread like dado on a table saw sled, and the part to receive the rail was cut using table saw and a Japanese pull saw.
Next, I glued up the infeed and outfeed table the same way I glue up the frame, only with more clamps. When glue up, the two pieces doesn't need to align perfectly, just make sure one edge of one board is on the out side all the way, so later I can trim it using that edge as a reference. the glue up almost used up all my clamps :)

The next is to finish up the infeed table crank, It maybe unnecessary,  but I also doubled up the crank screw mount. I drilled a through hole for the threaded rod, and chiseled out a hex hole for the nut,  that hole is not all the way through, and I use a washer to press the nut firmly in place. On the handle side, I used a spring inside the hole to eliminate the back lash. Note I mount the board on the lower rail on the under side, because my motor was so tall, and I don't want to have a motor hanging out of the frame, I made the frame 10 inches tall to fully cover the motor inside, so I have extra space under the lower rail.

Then to build the infeed and outfeed table. I cut the opening for the cutter head mount on the table saw just like cutting dado, I use a magnetic stopper to make sure I cut to the same position every time. I use 1/2-20 threaded rod as the support leg for the outfeed table. For three of the leg, I tapped the thread on the angle iron and locked the threaded rod in place with another nut. For the last rod, I screwed it directly to the table with some wood glue.

I originally made the belt guard cricked, it was not level with the frame. I didn't want to make it again, so I glued some MDF on to it and trimmed to square. The block of circular wood there is to prevent the key from sliding out of the pulley/shaft.

I made the fence and cutter guard exactly according to the plan.

Test run


I really like Dewalt's color theme, so I painted it black and yellow. I vanished all wood surface. The two table with oil base polyurethane, all other with water based polyurethwell.  The thought is I wouldn't introduce any moistrue to the infeed and outfeed table, so to minimize any wrappage. I primed and painted angle iron with Rust-Oleum metal paint as well.



 I needed a table top, so I laminated some construction lumber, I jointed two 12 inch wide panel and glued them then hand plane/ sanded to finish. It was really nice to have a 13 inch jointer at hand, and feels even better that is homemade!!


Tape holder

Emma loves doing crafts, and tape if a tool she use a lot. I always want to make a cute tape holder for her. I prototyped with some ...