[JerryBurks]

This question is only indirectly related to CNC machines but since the experienced woodworkers are here anyway....

I went to the local Home Depot today for some small stuff and found a deeply discounted Ridgid 4330 13" bench top planer (store display unit). Very dusty, no box or manual and missing a few insignificant pieces but otherwise new and at $150 I could not resist so I took it home. Darn impulse buys

Now, I was wondering to extract the cutter mechanism from the machine, remove the drive rollers and convert this into a nice 13" jointer (I have seen some builds for that) to flatten cupped or otherwise warped boards for the CNC machine.

On the other hand, I hate to destroy a working machine and might have occasional use for a planer, too. I was even wondering to leave it alone and just replace the flimsy feed and exit plates with a contiguous bottom table (maybe 3-4 feet long?) if it could double as a poor man's surface jointer. The drive rollers would have to be locked "up" for this purpose so they don't push warped lumber flat.

I have used a jointer a few times maybe 30 years ago so I don't really know what I am talking about. But does that sound reasonable? Any other ideas what to do with that thing?

Thanks, JB

[aarggh]

Over the years I've had numerous use of my thicknesser, but to be honest never used the jointer I bought, as I found many other ways to achieve what I needed done at the time. A jointer can be emulated by almost any tool, but for really quick results and ease of use and setup, in my opinion a thicknesser wins hands down if I had to choose.

cheers,
Ian

[OCNC]

I worked in a cabinet shop once that had a 24" wide planar that was actually a face jointer (as opposed to an edge jointer). It was an old machine and very massive so it may be from an age gone by but it worked quite well. It had a special sliding table that had many little fingers that would conform to the twisted shape of the board and then lock in position. Once locked the board would slide through the machine on the table and come out with a flat twist free surface face. You could then run the board through a conventional planer to get the other side faced and the thickness. As long as your boards aren't too long I would think that you could make some kind of a sliding tray that would restrain the vertical movement of the work piece to duplicate in concept what I describe above.

Chris

[louieatienza]

When I'm planing thin stock (and I have successfully planed acoustic tops and sides to less than .104" and even less) I use a "paten" that's basically a very flat slick surface like melamine particleboard, clamped to the infeed and outfeed. This helps a lot with thin stock moving around when run through. This also helps with older planers (and maybe some newer ones) that have rollers on the table, to mitigate "snipe."

To flatten stock with a planer, you would fix the board to the platen, and run the whole thing through. If the board is cupped or bowed, you can fix it to the platen with shims and hot melt glue. The key is to support any voids due to cup or bow between the work and platen. You might also be able to make edge clamps to secure the work that way as well.

Whatever you do you should try to make sure the grain runout runs "uphill" in relation to the cutter head, this way you can prevent chip-out. If this is unavoidable, sometimes running the board at a bias to the cutterhead can work.

[ger21]

A jointer can be emulated by almost any tool, but for really quick results and ease of use and setup, in my opinion a thicknesser wins hands down if I had to choose.

The only tool that can get the face of a board flat is a jointer. As Louie said, you can make a sled, and use shims to run a board through a planer, but it will take 10x longer than running it through a planer.
You can also mount the boards to your cnc, being careful not to distort it, and flatten it that way. But a good jointer can flatten a board in seconds.

We make a lot of curved moulding, and I CNC cut the blanks. With are vacuum table, the boards must be absolutely flat to hold them down. To get them flat, they must be run on the jointer. If run through the planer only, they won't be flat enough.


After I saw this, I had ideas about building a 12" jointer myself. But since I have daily access to a 16" jointer, I'm just going to sell my 6" and upgrade to an 8" with a helical head.

My recommendation, would be to keep the planer and use it as a planer, and look for a craiglist planer to get the head from to build a jointer. You can also find cutter heads on Ebay occasionally.
If you do plan to build a jointer, be aware that it's critical that the tables are absolutely flat.
And make sure that the cutterhead is mounted SECURELY.
And make it a habit of using push blocks.

[louieatienza]

The only tool that can get the face of a board flat is a jointer. As Louie said, you can make a sled, and use shims to run a board through a planer, but it will take 10x longer than running it through a planer.
You can also mount the boards to your cnc, being careful not to distort it, and flatten it that way. But a good jointer can flatten a board in seconds.

We make a lot of curved moulding, and I CNC cut the blanks. With are vacuum table, the boards must be absolutely flat to hold them down. To get them flat, they must be run on the jointer. If run through the planer only, they won't be flat enough.


After I saw this, I had ideas about building a 12" jointer myself. But since I have daily access to a 16" jointer, I'm just going to sell my 6" and upgrade to an 8" with a helical head.

My recommendation, would be to keep the planer and use it as a planer, and look for a craiglist planer to get the head from to build a jointer. You can also find cutter heads on Ebay occasionally.
If you do plan to build a jointer, be aware that it's critical that the tables are absolutely flat.
And make sure that the cutterhead is mounted SECURELY.
And make it a habit of using push blocks.

I'd agree in getting a jointer and keeping the planer, and this way you can get both faces flat and the edge jointed and squared. Jointer is great also for trimming cabinet doors and shutters. It can also be a money saver if you buy stock "in the rough," though you have to know what you're looking at. I used to bring a small block plane with me to the lumberyard.

I should add that a jointer is a very potentially dangerous machine to use, and one should have some familiarity with technique to operate one, as well as how wood machines in regards to the grain runout on the boards. Never ever wear loose clothing or jewelry when operating one. And like Gerry says, use pushblocks. When I had my cabinetshop, we bought a lot of "antique" tools. Today every jointer and planer has a round cutter drum. On our jointer the "drum" was square with the knives mounted on the faces(!). This was very dangerous as there was no anti-kickback or chip-size protection. I had many pushblocks, and it was still scary.

[JerryBurks]

Thanks guys, good advice!

My main problem is space. I can free up a spot for a planer but there is no way to set up a normal jointer that is maybe 48 or 60 inches long and even less 2 machines. The idea for the home-built jointer was a stand allowing to store the bed vertical. For operation I got to drag them out into the driveway, which will somewhat stress the goodwill of my neighbors and limit operating time. I guess I just need to move to get a decent shop. Really hard in urban Southern California.

Anyway, I will go the easy route first as you suggest and mount the planer with a longer table replacement (also to be tilted for storage) and see if that is good enough. Even if it takes much longer flattening boards with a sled than a proper jointer, that may be O.K. since I am not in production mode. I may get a 13" wide strip of 3/4" granite for that table.

I tried to plane some boards with the CNC machine and a 1.5" bit but holding this on the CNC table without stressing/bending is very difficult.