Greetings from the heart of the Ozarks!

This is my first attempt at building a CNC router. I have been reading and reading this and other sites to learn as much as I can and I think I am ready to begin.

Most of us 'guys' have to slip these projects under the WAF screen.:argue: (Wife Acceptance Factor) but after showing some of the finished work many of you have shared here, my S.O. has decided that I should build this. That leaves the first hurdle scaled with not even a scratch. :D

And, she even wants to HELP! :wee:

So let us begin:

Design: Adopting a partial JOES2006 and phooddaniel (www.buildyourcnc.com) concept.

(I dont have drawing software, so if anyone can point me to a free alternative, I can sketch up my plans)

Motors: 4 - Keling 425 or 495oz/in NEMA 23's. (If I don't use dual X then I can use the 4th for the A axis.)

Lead Screws X & Y -ACME 1/2-10 2 start and Dumpster nuts or maybe Rack & Pinion for X & Y with 1/4-20 ACME for Z.

Driver: G-rex 101 (It future proofs me to 6 axis later on.) The G-rex 100 looks snazzy, but is twice the price for the same functions. If anyone can tell me a good reason to go with the 100 rather than the 101, I'll consider it instead. I also looked at other geckos for their max 80VDC, but who really needs that much voltage anyway? Grex and HobbyCNC drivers operate at 50V or less.

Controller: I wanted to use EMC2 in the worst way with LINUX. But, if I go with a G-REX 10* driver, there is no way to interface the two. Waaa!!

So it looks like Winderz and Mach3 for now. Unless I go with other gecko drivers and use the printer port. Then I can use Linux and EMC2.

A DIY power supply made with a toroidal transformer and dual 10,000 to 16,000 uf caps. I'm looking at a few Antek transformers, but not sure what I can use with the 50V limit of the GRex. I don't want to fry anything with backcurrents.

Decisions.. decisions...

Skeleton:

Length:50-60"
Width: 30"
Height: 8" Z travel with total gantry height ~18"-24"

X torsion box: MDF with 2 - 1" black pipes or CRS angle iron each side and skate bearings for the linear slides.

Y torsion box: MDF with a single 1" pipe/angle top and bottom. (like Joes)

X axis: MDF or masonite(hardboard) with 3/4" drill rod. I'd like about 8" travel.

At some future point, I'd like the Y gantry to tilt 90' (or at least 45') so that my n'th axis can be for turning spindles or table legs with intricate designs. Sort of like a faux B axis.

And finally the heart of the build, the router.

A Dewalt 625 3HP variable speed. I realy like this unit. I've used it and wouldn't trade it for anything!

Maybe someday I can go to a flexdrive cable type spindle. That would make the 90' Y gantry movement easier as well as lighter. I wouldn't have to push 16# of router around.

Thats it for the preliminary in my head design.

Any thoughts so far on something I may have missed?

OzarkCNC

Looks like it'll be nice machine!

As for software, you can use sketch up by Google, here is link:

http://www.sketchup.com/

That sketchup program is good for a freebie. I must have a learning curve though, since all I was able to do in the last hour is make a plywood box, then I hit a wrong button and skewed it up. (Or was that screwed) Oh well...

Back to the ole drawing board.... again.

I played with Alibre a little bit last night. Man that is nice, but again, took me an hour just to make a box. I might have to forego the drawn plans and just build it as I go.

Thanks for the link...

Back to my build...

I am ordering most of my costlier parts this weekend. Then heading to the lumberyard early next week.

OzarkCNC

QUOTE=OzarkCNC;347863]Greetings from the heart of the Ozarks!

This is my first attempt at building a CNC router. I have been reading and reading this and other sites to learn as much as I can and I think I am ready to begin.

Most of us 'guys' have to slip these projects under the WAF screen.:argue: (Wife Acceptance Factor) but after showing some of the finished work many of you have shared here, my S.O. has decided that I should build this. That leaves the first hurdle scaled with not even a scratch. :D

And, she even wants to HELP! :wee:Now that is great![

So let us begin:

Design: Adopting a partial JOES2006 and phooddaniel (www.buildyourcnc.com) concept.

(I dont have drawing software, so if anyone can point me to a free alternative, I can sketch up my plans) There are tons of free cad systems out there. Following are some links.

http://www.freewarefiles.com/cat_3_34_3D-Modeling-CAD.html
http://www.freebyte.com/cad/cad.htm#2D3DCADSystems
http://www.eland.org.uk/pages/Misc/cadnotes.html
http://www.cadlogic.com/products/draftit/ That ought to keep you busy a few days trying all those out!!!!!(wedge)


Motors: 4 - Keling 425 or 495oz/in NEMA 23's. (If I don't use dual X then I can use the 4th for the A axis.)

Lead Screws X & Y -ACME 1/2-10 2 start and Dumpster nuts or maybe Rack & Pinion for X & Y with 1/4-20 ACME for Z.

Driver: G-rex 101 (It future proofs me to 6 axis later on.) Mach3 give you 6 axis of control as well.The G-rex 100 looks snazzy, but is twice the price for the same functions. If anyone can tell me a good reason to go with the 100 rather than the 101, I'll consider it instead. I also looked at other geckos for their max 80VDC, but who really needs that much voltage anyway? Grex and HobbyCNC drivers operate at 50V or less.Well let me start by gently correcting a slight misunderstanding you have. The Grex whatever # you apply to it is not your drive system. the Grex is a high speed pulse engine that basically takes the place of the pc in that it supplies step and directions signals. Mach is the user interface used to be able to control the step and direction the Grex outputs. Your drives will be something you build or you could buy them from Gecko, ie 201 up through 20? for step motors and the servo drivers are numbered in the 300 series. Even if you choose to use a Grex, you still have to have these drive components.

Controller: I wanted to use EMC2 in the worst way with LINUX. But, if I go with a G-REX 10* driver, there is no way to interface the two. Waaa!!

So it looks like Winderz and Mach3 for now. Unless I go with other gecko drivers and use the printer port. Then I can use Linux and EMC2. I will not try to disuade you from EMC2, but if you will look at the number of people having success with Mach and compare that to the number of people having success with E, I think you will come to the conclusion that Mach is a much easier way to go, even if it does requires winderz!(wedge)

A DIY power supply made with a toroidal transformer and dual 10,000 to 16,000 uf caps. I'm looking at a few Antek transformers, but not sure what I can use with the 50V limit of the GRex. I don't want to fry anything with backcurrents.

Decisions.. decisions...

Skeleton:

Length:50-60"
Width: 30"
Height: 8" Z travel with total gantry height ~18"-24"

X torsion box: MDF with 2 - 1" black pipes or CRS angle iron each side and skate bearings for the linear slides.

Y torsion box: MDF with a single 1" pipe/angle top and bottom. (like Joes)

X axis: MDF or masonite(hardboard) with 3/4" drill rod. I'd like about 8" travel.

At some future point, I'd like the Y gantry to tilt 90' (or at least 45') so that my n'th axis can be for turning spindles or table legs with intricate designs. Sort of like a faux B axis.

And finally the heart of the build, the router.

A Dewalt 625 3HP variable speed. I realy like this unit. I've used it and wouldn't trade it for anything!

Maybe someday I can go to a flexdrive cable type spindle. That would make the 90' Y gantry movement easier as well as lighter. I wouldn't have to push 16# of router around.

Thats it for the preliminary in my head design.

Any thoughts so far on something I may have missed?

OzarkCNC[/QUOTE]

Hopefully the links and info I gave you will help

Mike

Well let me start by gently correcting a slight misunderstanding you have. The Grex whatever # you apply to it is not your drive system. the Grex is a high speed pulse engine that basically takes the place of the pc in that it supplies step and directions signals. Mach is the user interface used to be able to control the step and direction the Grex outputs. Your drives will be something you build or you could buy them from Gecko, ie 201 up through 20? for step motors and the servo drivers are numbered in the 300 series. Even if you choose to use a Grex, you still have to have these drive components.
Mike
:o
Well that never even entered my mind that the GREX was just an INTERFACE rather than an all-in-one driver. Shhhhhhiiiippp!

That changes everything. I dont want to pay $200-400 just for the luxury of using ethernet instead of the printer port. I still need to hook a computer to everything anyways. Maybe somewhere down the road yes, but I am just a po' boy.

So then the next question that this poses is that I would still need to buy 3 or 4 gecko 201, 202, 203V's to drive the steppers.

Sooooo-

Would I not be better off choosing the HobbyCNC HCNCPRO board that does the same as all of the gecko's combined?:confused:

Is this right? I am a little cornfuzed at the moment.

Therefore, by going with the HCNCPRO board, I can only use the Keling KL23H286-20-8B 425 oz/in steppers and not the 495oz/in steppers.

(The 495oz/in steppers are 4 wire and the hobby board doesnt support 4 wire motors)

I could however use other than Keling as long as they were moer than 4 wire steppers.

GROAN (nuts)

I wanted to have everything here in the next week or two. I guess I didn't have this thought through as I had planned.

I'm going to bed, maybe I can get a clearer grasp in the daylight. Zzzzz

OzarkCNC

[QUOTE=OzarkCNC;348271]:o
<snip>
Sooooo-

Would I not be better off choosing the HobbyCNC HCNCPRO board that does the same as all of the gecko's combined?:confused:

Is this right? I am a little cornfuzed at the moment.

Therefore, by going with the HCNCPRO board, I can only use the Keling KL23H286-20-8B 425 oz/in steppers and not the 495oz/in steppers.

(The 495oz/in steppers are 4 wire and the hobby board doesnt support 4 wire motors)

I could however use other than Keling as long as they were moer than 4 wire steppers.

GROAN (nuts)
<snip>
Get the HobbyCNC kit with 305oz motors. The motors match the board. Not all steppers are rated the same. Apparently the amount of torque you can get depends on whether the driver board is bipolar or unipolar.
I got this in another post.
"I would go with the 305oz in, they can be used later on with a bi-polar board at 425oz in. providing they have 8 wires.

Joe
"
It would appear to me that the motors are the same at least rating wise. They do have 8 wires by the way.
The HCNC kit has everything you need minus a transformer and enclosure. I have my kit built and the motors hooked up and they appear to work well. Of course they are moving nothing but air at the moment.

I just went to their site........wow what a deal. I am not one to normally recommend someone build their first machine with kits, but they have a 4 axis, 4-305in 23 frame motor combo for $192. I'm thinking that is a great deal, assuming you can solder the pcb and compontents correctly. With 6 thumbs on two hands, I find it kinda hard!:D
Mike

I just went to their site........wow what a deal. I am not one to normally recommend someone build their first machine with kits, but they have a 4 axis, 4-305in 23 frame motor combo for $192. I'm thinking that is a great deal, assuming you can solder the pcb and components correctly. With 6 thumbs on two hands, I find it kinda hard!:D
Mike

I went to look again. So I had to order it.

Is anyone here using the 4AUPC driver kit? Any comments? Good-Bad-Ugly?

The deal looked mighty fine for a beginner like me. I can always upgrade later.

I am basically buying the motors and the chopper board is free.

Now the only bad thing is they are gone for 2 weeks. So even though I ordered today, my stuff won't be shipped til after the 10th. :violin:

I should be just about ready for the electrics by then.

OzarkCNC

1018 or 4140

Mcmaster has 1018 1/2 10 2 start 6' threaded rod for $52.11 each

the 4140 is 79.42 each.

Is the harder 4140 worth the extra $27?

Have you considered timing belts as your drive mechanism? I've read it is much smoother and faster than threaded rods.

Mike

I've considered belts and rack and pinion.

Honestly, I dont know enough about belt pulleys and gears to know how to reduce the speed down to a level that the 305oz/in motors can easily pull.

What about the belts stretching/backlash? Is that a problem? My gantry is probably going to weigh in at close to 30# when complete.

If you can help me pick out the components, I would gladly try to do it that way. Belts are faster and wouldnt cost me $100+. PM me or point me to PICTURES. I am a quick study if I can see a picture of it.

*EDIT* I've looked on the ECONOBELT (http://www.econobelt.com/) website before. Just looked at it again and the SDP-SI website too. They both probably have what I need. I just am not sure what I would need. I would still need some sort of screw for the Z axis, or a combination belt and screw. *END EDIT*

OzarkCNC

OK here goes my thoughts on belts after much reading.

I could probably do it, but still have trouble with the concept of how far to gear down the motor (or at all).

T will be considered gantry travel at 1 revolution of the stepper. Since the stepper can rotate at up to an arbitrary value of 1000 RPM, I would think that the pulley should be quite small.

So to figure out T I needed to put the smallest pulley available on the motor which would be 10 tooth.

THe 10 Tooth pulley has a diameter of .617".

So T= .617 * 3.14159 = 1.938" per revolution

A stepper has 200 steps per revolution.

1.938/200 = .00969 at 1:1 (.010 rounded) Pretty coarse, isn't it?

My 4AUPC driver has 1/2, 1/4, 1/8, and 1/16 micro stepping. This means that I can get down to .010/16=0.0006" per step theoretically at 1:1.

This only leaves one question unanswered. Is the 305oz/in stepper going to be able to haul the 16# router plus the weight of the gantry at 1:1?

Also at 1/16 micro stepping, I can ideally get rapids of *up to* 121 IPM,. But only in a perfect world that doesn't take into consideration mass and acceleration.

Am I on track so far?:confused:

Its taken me several hours, but here is the rough sketch of the table and the X drive.

It took me 2 hours just to get the skate bearings right.. Sheesh...:tired:

Eventually I will try to get the gantry added.

I'm in a mood. :violin:

Skectup is giving me fits and I am getting frustrated. I've seen so may nice renderings and I take 2 days to draw a freekin box.

I also can't seem to get any positive feedback on BELT driven gantry. I did see COOGRR's build plus all of his youtube videos. I think I need to talk to him personally or someone else that has belts driving their machine.

I do think I need to gear all of the axis down at least 2:1 and use the 2nd pulley as the main drive to take all sideways torque off of the motor itself.

I'd like to have my whole build planned and measured for the most part, but it looks more and more like I will be building and changing things as I go.
:drowning:

After watching this site for a number of months I have begun construction on my router table. It's still pretty warm in LA in a metal shop but here goes nothing.

Ozark,
I plan on using belt drive and reduction for all three of my axis setups. Within a couple of weeks I will be able to let you know the outcome. My steppers are 720 oz. I am running them with the Gecko 203V. My drive pulley is a 16 tooth driving a 52 tooth on the shaft. On the ends of the x axis shaft I have another set for both sides. The total gearing is about 6:1. I wanted to go with rack and pinion because of the lower cost as compared to screw. My linear slides are 35mm THK. They should hold up but they add alot of weight to the total project. My table is 120" long by 60" wide and 10" of z travel. This allows me to be able to cut a whole sheet and still have room on both sides.

OzarkCNC,

Getting accustomed to SketchUp is not too difficult as long as you focus on one concept at a time. Don;t worry about applying materials or colors to objects... focus on the formative elements, like taking the rectangle tool and drawing a rectangle on a plane, then using the push/pull tool and start having fun. You can then start to draw simple geometry and push/pull them on existing faces. You will have to get accustomed to the cursor and the intuitive way it snaps to objects. Also, use the scroll wheel on the mouse to rotate in 3d. That will help you visualize all of the pieces that you need to alter.

Maybe it is just me, but I think you can get 90 percent of the way toward your build a lot faster by just rough cutting a prototype out of 2x4s.

I was surprised with how relatively easy it has been to jump from my poor craftsmanship with wood to equally modest results in aluminum framing from angle, etc. It might be worth your time to play with this a little.

IMHO, I tend to spend way to much time on drawings, and it distracts me from building.

I've got real world commitments to do this weekend, but come monday, I am heading to the my lumberyard and getting some more red oak, then pick up some masonite and hardware.

IMHO, I tend to spend way to much time on drawings, and it distracts me from building.

This is true. I've been obsessed with providing such a detailed accurate depiction of what I want my machine to be. And to what end 6 months from now?

I'll have a neat drawing and probably no CNC router to make chips. So instead of worrying about what it should look like, I am just gonna start sawing, nailing, gluing and screwing until I have something that I can at least flip a switch on. Then I can worry about perfection later.

Got my 4AUPC driver board and 4 motors from Hobby CNC. Startred soldering last night at 11:PM was done with the board at 6:00.

Applied power and BOOM! The A AXIS chip exploded. I have no idea why. I couldnt find any traces that were shorted, but thats what it acted like.

Was able to get Vref on all 4 AXIS even with a hole in the 4th chip. I took it out though just so it didnt cause further damage to the board.

Now I need another SLA7062M. Hobby CNC wants 12 + 7 shipping. Anyone know where I can get one cheaper?

If not I'll just order it from Dave. :o

Got my 4AUPC driver board and 4 motors from Hobby CNC. Startred soldering last night at 11:PM was done with the board at 6:00.

Applied power and BOOM! The A AXIS chip exploded. I have no idea why. I couldnt find any traces that were shorted, but thats what it acted like.

Was able to get Vref on all 4 AXIS even with a hole in the 4th chip. I took it out though just so it didnt cause further damage to the board.

Now I need another SLA7062M. Hobby CNC wants 12 + 7 shipping. Anyone know where I can get one cheaper?

If not I'll just order it from Dave. :o

You can try requesting a sample from the manufacturer. I haven't found those chips to be inexpensive. When I have tried to get the chip from the retailers recommended by the manufacturer, they did not have it in stock (for quite a while).

I looked up that part at newark.com ( a large local distributor that is usually very competitive on price / shipping ) They may not be the absolute cheapest, but you will look hard to beat them.

http://www.newark.com/jsp/Semiconductors+&+Prototyping/Interface+&+I/O+Controller+ICs/ALLEGRO/SANKEN/SLA7062M/displayProduct.jsp?sku=61H9899&_requestid=164990

The price you were offered seems pretty reasonable, but Newark does carry it.

BTW- amazing tenacity on that board build.

Thanks,

I just ordered one from Dave@hobby cnc. If I ever need more than one, Newark looks to be the way to go.

My Bernz-a-matic butane soldering pen bit the dust today trying to desolder the 21 pins. It sputtered and died & was only 3 days old. Waaa!

Like this one:
http://cgi.ebay.com/bernzomatic-micro-torch-kit-solder-weld-6-in-1-kit-new_W0QQitemZ160167294937QQihZ006QQcategoryZ46413QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Now I have to buy a new one. I'm thinking about getting one of those STATIONS that has an adjustable heat control.

Any recommendations?

Something like this any good?

http://cgi.ebay.com/Soldering-Iron-Station-tmc-08-600-free-solder-pump_W0QQitemZ140165471508QQihZ004QQcategoryZ46413QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Sorry for the dead link for people that view this after ebay takes the auction down.

I just got an offer from SHOPSMITH for their 5' connector tubes.

Would they be adequate for X rails?

For $27. thats not bad and they are shiny. Or could I do better at my local steel supply/home center?

I lucked out at a Habitat REstore in Little Rock today. I picked up 6 chrome heavy duty hand rails that are 4+ ft long, so it looks like my build is changing to a 4x4.

And the best part. I got em all for $15.

I've never seen anything quite like them, they are circular in shape, but slit and tabbed underneath, giving them more rigidity. So I am brainstorming now. I could use Linear bushings or use the notch underneath for the skate bearing to ride in.

Will upload a pic later.

I'm ready to start building!

Here is a running update of what I've done in the last 3 weeks.

PROGRESS:

Blew the A-Axis chip during that initial test on 10-10-07. I think a stray lead snip shorted out one of the pins. It actually blew a chunk out of the center of the driver.

Note to self. Buy Inline FUSE holder. (chair) That was a $16 mistake I won't make again!

Dave from Hobby CNC sold me another 7062M driver chip. I still have yet to get it installed.

Desoldering is such a pain in the (nuts)

Have everything for my Power supply.

Had a 24VAC CT 10A transformer from a previous project.

NOTE: My next post will detail on how I added a 5V secondary to an existing transformer. (Just in case I need it)

A few 20,000 uf 45V Electrolytics. If you need one, PM me. I have an extra.

Got some components from MCM last week.

Inline fuse holders:rolleyes:
microswitches with red pushbuttons (Like on vid games) for my E-STOP or later for pendant.

Full wave bridge rectumfrier

New TENMA variable soldering iron for $15. Hated the butane one with a passion! Could have got it for 10, but took to long to pay out my cart.

25Watt 680ohm resistor for bleeding off the PSU cap.

100 Skate bearings $30.89 from ebay SHIPPED!

Got some 3/8 x 16 threaded rod for my Z axis (for now and some coupling nuts) I found a concrete anchor that threads onto the 3/8 rod and has an opening on the other end that will nearly fit my NEMA 23 motor.

I might be able to use it as a coupling until I can get some Lovejoys but it doesnt flex, so maybe not. I'll see for 89¢.

Some 1" x 1/8" aluminum angle for my skate bearing slides. So I can start building the Z axis at least.

Cannibalised an old ATX power supply for some components and some awesome heat sinks for the stepper board SLA7062's.

Some nice old 2x10 pine waterbed frames were given to me. I planed the finish off and they are true and straight for my table. Not like the #2 grades you get today.

Have a Dell Desktop PC that went through a fire. Just smoke damaged, but has XP PRO on it. I can't see throwing it out.

STILL NEED TO DO:
Get misc wood, metal. Get my plans on paper. So far they are still stuck in my head and evolving.

Looking at TOUCH PANEL screens, but I don't know. Are they worth the money and how small should I be willing to go. I don't think anything smaller than 10"

Or I have a PABLO Graphics tablet. But that is just 3 more wires and more space. Although it may come in handy later on for the CAD portion. Will shelf that for now.

BOLTS: I've looked at H.D. I cant find any 5/16x1 1/2 with threads all the way up the bolt lenght. I need full threads for my skate bearings.

I think my next stop is going to be boltdepot.com (http://www.boltdepot.com/default.aspx). I just hate to make several orders. I wish I had a good idea on how many to buy of nuts, washers, spacers, U-bolts etc. (Any suggies?)

Oh and I just remembered. A printer cable. All I have are the old DB25 to Centronics. I could cut one off and get a DB25F shell and wire it up. Would be cheaper than a whole cable.

And finally, I need to order my belts and pulleys. I guess econobelt (http://www.econobelt.com/)is the way to go.

Thats enough typing for tonight. I'm wiped out... Zzzzz:tired:

Got around to soldreing the replacement A-AXIS driver chip in my 4AUPC HobbyCNC board.

Everything went smoothly. Applied power and nothing smoked this time.

So I discharged the capacitor in my PS and hooked up the motor to my X AXIS.

Power ON. Motor locks like it should. Good.

POwer OFF - Drain PS capacitor.

Hook motor to A-AXIS.

Power On. Motor Locks like it should. SWEET! I did it right.

Now I figured on trying the other 2 AXIS since I hadn't tested them with a motor before.

Power OFF. Discharged cap.

Hooked motor to Y axis.

Power on. BOOM! Smoke and flying parts!

Now the Y AXIS is toast after 2 weeks of turning it on showing my neightbor and GF that what I have built works and waiting 2 weeks to get the replacement A soldered in.

I am angry and upset.

See pics HERE:

http://ozarkmark.smugmug.com/gallery/3751789 (http://ozarkmark.smugmug.com/gallery/3751789)

Gave up on 4AUPC board and sold it.

Ordered new HCNCPRO kit from HobbyCNC. Dave gave me a good deal.

Maybe I can get it together without setting it on fire. (flame2)

Still have to put up the DIY transformer 5V tap and the pic of my chrome handrails that will be my linearslides.

I need to mic them to see if I can use bearing blocks or will still have to use skate bearings.

Off to Home D. to return a thermostat and look around some more.

I found quite a bit of stuff on the FASTENAL (http://www.fastenal.com/) site, bit it is a bit higher priced. I do have a local fastenal, so maybe I can get a better deal on some fasteners or spacers.

Thats all for now.

Ozark I'm sorry you have had problems, but I promise you the end result is worth the effort.

Mike

HobbyCNC PRO board arrived today.

Started assembly.

Taking extra time to make sure everything is PERFECT before I apply power to this one.

Will provide detailed pictures later.

I finally got my computer inside and gave it a quick look.

It seems to be mostly smoke damaged with only slight melting of the front of the case and the CDROM eject button.

http://ozarkmark.smugmug.com/gallery/3832950#221666893

Here is a pic of the Stainless/Chrome handrails that I will be using for my Linear slides.

http://ozarkmark.smugmug.com/gallery/3832950#221668151-M-LB

Bought some stainless 5/16" x 1 1/4" bolts & nuts for the skate bearings. I also bought some M11 washers to use as spacers. I'm lucky to have a Fastenal in my town. Spent under $10.

They are higher than boltdepot.com, but they are close and no waiting.

Hopefully the weather will be nice and I can work a bit more. Or I should say START outside.

If I can get to bed before daylight, that is...