Jump to content

Anyone used WaterJet cutting system for wood?


Newbie

Recommended Posts

I did a search - "water jet cutting wood", this is one of the results:

http://www.mfg.mtu.edu/cyberman/machining/non_trad/waterjet/

There is a paragraph about the disadvantages toward the bottom. It might be worth a test with a sample of the material you plan to use. Since this is going to be used in furniture, my concerns would be:

1. Possible discoloration to the finished oak face veneer from the cutting medium. Oak is particularly prone to this.

2. Square, clean cuts so that further machining is not required.

3. Delamination of the plywood from contact with water.

4. Machining that doesn't require a complete cut through the material (rabbets, dadoes, etc) probably cannot be done with water.

George

Link to comment

We have used waterjet cutting on some solid wood, 3x and 4x ipe to be exact. We've been moderately pleased with the result, largely because there isn't really another option to achieve what we needed. Laser cutting was too slow and generated too much heat in those thicknesses.

George makes several excellent points, the sharpest one being you will likely NOT get clean edges. And I would be very worried about delamination. Almost anything I can think of cutting in 3/4" material can be done quickly, with known results, on a horizontal-bed CNC router. Most every cabinet shop of any size has one and most are willing to take in custom work.

Good luck,

Link to comment

Hey George & Travis,

Thanks a lot for both of your replies. You're right, I should have them cut on some of the wood I'm using first to actually see the results. I'm not doing any partial routing cuts (rabbets, dadoes, etc), every cut is completely through the piece.

I haven't used a horizontal-bed CNC router before. Is that a computer-aided device too? Does it use a CAD file to make it's cuts?

I really appreciate all this info - I'd hate to spend $400-500 on wood and have it wasted.

Thanks,

Dave

Link to comment

Yes, CNC Routers do use CAD files. There are also a range of different types of CNC. For what you want to do, they will all do the job, I wouldn't even think of using waterjet. I think you'll find waterejet is also more expensive.

How many units are you planning to make? If it's just the one, most likely a cabinetmaker using ordinary hand methods will be the most cost efective due to the programming and set-up costs involved with CNC.

What are you doing to the edges? Edgebanding? Then waterjet would again be unsuitable.

Link to comment

Thank you everyone for your great responses. I'll check for CNC-routers tomorrow.

David, yes I'm going to Edgeband. But also, the desk I'm building has curves & angles, so it'll be interesting to see exactly what the limitations of CNC are. I am making only 1 unit, if by that you mean 1 desk. I'm trying to figure out how to include an image of the desk I've designed, so you can have some idea of the shapes. Oops, just figured it out. Below is the desk.

Thanks so much, everyone.

Dave

Desk%20with%20shelf-small.jpg

Link to comment

Umm, Newbie, I'm glad you posted an image.

As a one-off, and if cost is an issue, this could, and should be done with templates and a "hand" router (in agreement with David). If learning CNC is the goal...it is time for you to do some research and reading. You have gotten a lot of good advice here. FYI, this project would be well within the very basic capabilities of a CNC. Watch the manufacturer's videos posted @ Woodweb

Definitely put the waterjet to bed.

Link to comment

I want to thank everyone for all the great advice - CNC is definitely the way to go - I've looked at the videos, pretty cool stuff. I didn't realize it would go through the wood that fast!!! Shouldn't take an hour to cut the whole desk, if that long.

You know this brings up a question:

As I'm designing this piece, I'm running into a quandry. As I lay the pieces out, let's say the vertical pieces laid out horizontally(as looking at the front view), on the pieces that butt up to the next piece, is there an accepted method of (when positioning left to right): do I put the right piece's left edge ON the left piece's right edge, or a specified distance from it (I realize this could be .001 or so, definitely small). I haven't had a design make it outside of virtual furniture yet, so I want to make the right adjustments. Sorry if this is confusing.

Thanks,

Dave

Link to comment

I knew I probably wasn't explaining that well enough. Let's try again.

This applies to any viewing angle, but I'll use the Front.

Okay, as I'm 'positioning' my 3D objects, using the Front View (straight on, no slightly-off angle), I've got two vertical objects 3/4" wide that butt up next to each other. They're two pieces of plywood that will probably have a bolt going thru them to lock them together, creating a 1.5" wide piece.

Now, as I'm laying this out in VW, how close to the edges of one piece do I place the next piece. As I'm looking at the side vertex of each adjoining piece, do I place the vertex on top of the other, or do I zoom way in and place the vertex as close as possible without overlapping?

The fact that there's no readout of position when you're working with a 3D object, like there is with a 2D polyline makes it real confusing and difficult to get accurate positioning.

I hope this explains this better.

Thanks, Dave

Link to comment

I would usually have them tight against each other. Snap to Object should position the part where you want. What we create in VW is only a graphic representation of what may become a real object. For graphic purposes, you might want the two layers of plywood to be visible in a rendered view. This can be done by beveling edges. I wouldn't bother with minute position differences in a drawing. My focus would be on which "finished" dimensions are important, such as:

1. Overall size - will it fit in the space, or suit the use?

2. Interior sizes - does something have to fit inside?

3. Efficient material use.

Keep in mind that actual material sizes vary from their nominal description - 3/4 inch plywood is not exactly 3/4 inch thick, just as a 2x4 is not 2"x4".

George

Link to comment

Thanks, George. I get what you're saying. My only question is, if I'm designing something like the desk pictured above, the distances or positions or tolerances of one piece directly affect the other pieces. IE, if the positioning of one vertical side is slightly off, it will affect the alignments of all the pieces that depend on that pieces position. Boy, as soon as I start explaining, it all sounds like gibberish!

I can see, in designing a room where you're positioning furniture does not have to be so accurate, but in building a piece of furniture, I would expect that it has to be extremely accurate.

Which gets back to my original frustration on position markers of 3D objects. I still wish there was a better way to get their positions in 3D. Maybe I should take that up with VW?

Hope that explains it better. Thanks for your help.

Dave

Link to comment

Try to keep it simple. The desk above has some repeating elements. The 2 side boxes appear the same, the center has 3 openings that appear the same. Start working in 2D, create a layout (guides), then create the 3D version.

"the distances or positions or tolerances of one piece directly affect the other pieces. IE, if the positioning of one vertical side is slightly off, it will affect the alignments of all the pieces that depend on that pieces position"

You've just described the heart of all building.

George cook_armoire.jpg

Link to comment

George,

Nice armoire!

Newbie,

I have to agree with Islandmon:

"That desk job looks to be an excellent candidate for the good ol' Table Saw, Router ... and cordless screw gun ; ) "

The CNC overhead alone could exceed the time required using the good ol' method, unless you contract out the CNC portion to a qualified cabinet maker.

Building and joining the base components before making the desk top eliminates the need to estimate and apply tolerances. Just fit to resulting size.

Link to comment
Shouldn't take an hour to cut the whole desk, if that long.

Yes, but most likely it will take longer to progam and set up the machine. CAD files have to be re-interpreted for correct tool path.

do I put the right piece's left edge ON the left piece's right edge, or a specified distance from it

I would lay out the parts to fit on a standard size panel - leaving at least a cutter distance apart (typically 10mm - check with fabicator), This way you can check that you are getting the most effecient cutting from a sheet. It also gives a chance to re-design parts if they are too inefficient in material usage - before it's too late and the CNC guy calls up and says he's run out of board and needs another sheet!

The fact that there's no readout of position when you're working with a 3D object, like there is with a 2D polyline makes it real confusing and difficult to get accurate positioning.

Can't agree with your comment. The fact is using a graphical approach - 3d snapping to align 3D objects - is so much more efficient, and at least as accurate, than a numeric method - using co-ordinates, why would you bother with the latter? But in fact you CAN get co-ordinates using the cursor anyway to snap anywhere on the object, and you can move/drag using either the tool bar or move command, so your statement doesn't hold water. And if VW is accurate enough for machine design, it's certainly accurate enough for furniture!

As far as tolerences go, the standard engineering concepts apply - ie you can't expect a 1" peg ot fit in a 1" hole. Specifying mating parts, as your example appears to have, requires a further level of sophistication in your CAD file - there's aslo the matter of internal radii being limited by the cutter radius. You're going to have issues trying to edgeband the internal angles on the end panels.

As has been said before, on a one-off basis, a table saw and router appoach is most likely going to be quicker, cheaper, and much more likely to produce a workable result.

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...