Large Planing/Milling/Routing Table

[UrbanLogger]

I need help!

I'm a woodworker in Memphis, TN. I have my own sawmill and regularly saw HUGE (30" x 10'+) planks and natural-edged slabs that exceed the jointing and planing capacity of any machines that I have access too. I am growing weary of hand planing these monsters and want to built a 3 axis table to do it for me. I also have occasion to make routed signs.

I was thinking a 36"-48" deep and 12' long table with rails running lengthwise and a 3 1/4 hp router riding on a sliding beam across the rails. The idea being to shim and clamp the lumber to the table, router-joint it flat on one side and then flip it over to router-plane the other side.

As long as I'm building it, I figure I might as well make it work in 3 axis and be CNC capatible.

Has anyone heard of anyone making a CNC table to perform this function?

[Mcgyver]

Urban, I’ve often thought about making a similar machine – something that would take the place of the a jointer and planer so I could finish rough cut hardwood. There are many great examples here of diy heavy duty cnc routers.

one challenge I see is how to hold the work piece without the clamping action distorting it. it’s those first two cuts on a jointer that create the references and that is done with the work piece ‘floating’ that I’m not sure how to replicate with cnc?? Any ideas or mass production precedents on how to hold rough lumber?

[Thomas A]

I too would like to make a large CNC machine 4' by 10' with about 9" on Z-axis. I see plans out there. http://www.machinetoolcamp.com. But they always want you to purchase some expensive parts from them (linear guide system).

Has anybody yet constructed such a machine? I was thinking of making one based along the JERGO lines using Al for gantry with a steel table with wood where it makes sense to keep costs down - perhaps with dual pipe rails to better support the gantry.

Any comments?

[UrbanLogger]

Thanks for piping in here, guys.

I gave this a lot of thought today as I hand jointed a 14" wide 7' long piece of 6/4 live-edge Cherry today

Luckily the other side made it through my 15" planer

I've either got to build this thing or buy a $3000+ 20" jointer and even that won't be enough for a lot of my wood.

I've seen boatyards that used a rotary planer mill to size timbers. What I'm thinking is kinda the same idea except it would have the added function of being able to cut my check arresting butterflies for me with a few clicks of the mouse

To hold the lumber still while the router's doing its thing would be a matter of threaded "dogs" along the sides and positionable threaded "jacks" on the face of the work table to "toe" up here and there to make it stable. With CNC you could program it to start at the highest point and take it off in many light passes.

I'm going to start a rough drawing after reading over the JERGO material--it's been a while since I stopped in here

[ViperTX]

Hmmmm.....so, let me throw out some ideas....have you seen the surface planing disks that attach to an arm saw's spindle....you know the inexpensive planer, I would use the same concept if I were going down the rotary planer route.

Here's what I know about the rotary planer route that will accept 30 to 50 inch wide lumber x 10 feet, it will cost you more to manufacturer then buying a 54 inch wide-band sander.

[ger21]

You can't flatten boards with a wide belt sander.

Using a CNC router as a jointer/planer doesn't require anything out of the ordinary. Any router will do the job.

A 4' x 10' router is going to cost a minimum of $5K. Probably more.

[dneisler]

Sounds like some big heavy lumber. As far as plans go, I belive the CadCut plans would a good starting point, as they appear, to be ALOT stronger than the MTC, but as you mentioned, they do require the linear system. Expect to spend $5-6k on it.

I just bought the plans myself, and I am slowly starting the build.

[dansutula]

Jointing lumber was one of the inspirations, objectives and justifications for my ongoing big CNC router project. (Status - Thus far I’ve purchased most of the major parts, and I plan to start building soon.) I believe there are a number of approaches to surfacing. The Lucas Saw Mill was available with an optional 3.25 HP router "fly cutter" or "face-milling" type slab surfacer. This option appears to have vanished from the Lucas Mill sites so perhaps it did not work well or did not sell well. Alternately, I was thinking of using a 3.25” electric hand planer with a custom shoe mount. For very heavy roughing it may be possible to use a dado or table-saw-type moulder blade on a custom attachment made from either a portable table saw, a radial arm saw head, or even a circular saw. Depending on how you design and build your router, it may be possible to use the router as a linear guide for manual push/pull or crank feed of the planer head. You will need good “hold-back” control to prevent the cutter from over-feeding itself.
Good Luck and Keep us Posted!

[wizard]

Hi Urban;

You likely already know that people have been doings something similar manually for years. Maybe not quite on your scale but certainly in place of a jointer. This also works great for end grian products that need to be flatened.

As you already have pointed out you can't get a flat suface fi the stock is not resting solidly. On a muach smaller scale and with a manually operated router I have used shims and hot melt glue underneath the rough surface. Clamping can be a trick especially if you are working with cut edges. On option that works is to levea the piece long for downward clamping. Another option is to press into the plank from the ends with gripping plates, sort of like a vise. Gripping from the side is probably out of the question considering that yo have natural edges, but is likely to work for other objects.

This sort of arraingement still takes time as you have to use a roatry tool that is likely to be small in diameter. I would suggest though that you consider a custom spindle in either R8 or ER tapers to allow easy access to differrent tooling.

As to the machine if you just want to joint and plane them it should be rather simple to build. The biggest issue being building a strong frame that is straight enough.

To cut butterflies and to do almost anthing else really involves taking the machine to a higher level. By this I mean you will have to build a machine that is more repeatable and accurate than simply a fancy jointer/planer. Not impossible of course but likely to have a dramatic impact on what the mahcine will cost.

The other issue is that I suspect htat the machine will have to be a bit more rugged than the average router project seen here or for that matter most commercial routers. Oftne the large router here are designed to work on plywood or other materials that are relatively light. I suspect you planks are very heavy.

So ideally the machine would have rollers or other items built in to help with material handling. Not seeing your facility you may already have a solution to this issue. I just see the need to build the machine differrently than most routers I've seen.

The other option is to scan the resources for a used planer mill. Yeah I know that even a very old one is somewhat expensive but this would be an ideal solution. You never know though you might just find a bargain. You also end up with a piece of capital that migh be applicable to other business interests.

Dave

[spalm]

Urban,

Not knowing your real expectations or budget, I see two machines here. A 10 foot long CNC will be a real expense. My thought is to build a manual (hand) operated router jig for jointing and a smaller CNC for sign making and butterfly cutting etc.

A strong torsion type bed design with angle iron rails and Vbearings for a gantry will give you a cheap way to hold a router over your long boards and let you flatten them by just guiding the router by hand. If you already have the patience to hand plane, this will speed things up a lot. The clamping techniques you described sound fine.

Then build a second smaller machine CNC style to do your sign cutting et al.

Steve

[Geof]

Years ago I met a guy who had built a machine to do something similar to what UrbanLogger is describing. Actually he did not build; he modified a lathe with a 30 inch swing and a twelve foot bed. He turned the headstock into an indexing head with a lock on the spindle, put a belt drive on the shaft for the carriage feed and mounted a big router on the cross slide. Then he held pieces of wood up to about 3" x 12" between the spindle and tail stock and routed bevels along each edge. These were then glued together to make big hollow wooden columns which returned to the lathe that now functioned as a lathe; the spindle rotated and the router turned them cylindrical with a slight taper. Then the headstock went back to being a dividing head and he routed flutes down the length of the tapered cylinder. Then they were painted white and became fake Doric columns at the main entrance to someones fancy house.

As Spalm says you need a base strong in torsion so all you need to find is someone who is throwing out a big lathe.

[Mcgyver]

Originally Posted by wizard On option that works is to levea the piece long for downward clamping. Another option is to press into the plank from the ends with gripping plates, sort of like a vise.

Dave with either of these you do not avoid the problem if inducing bows, twists, cups etc - ie you're not going to end up with a flat reference surface as if jointed. for the secondary planing op yes, but with lumber in the rough, there still needs to be a method to hold it without distorting - not unlike the guy who tries to clamp an irregular casting only to find after machining its far from flat and square as the clamping itself introduced twist.