The incredible cheap build is building boats #31 - Western Washington, USA
 

My build is, by necessity and design, intended to be done as cost effectively as possible. Here are the guiding principles;
a) 96x48 cutting area
b) using available materials to whatever degree practical, consistent with reasonable safety.
c) stick as closely as practical to the MechMate gantry.
d) have as small a footprint in the household finances as possible.
e) have the capacity to bootstrap into commercial use
f) rely on open source software as much as possible
g) teach myself new skills

So, with those in mind, as a starting condition my table is constructed of four immensely rigid torsion boxes and two 4x6's x 10' long... made from materials on hand.

http://i3.photobucket.com/albums/y58...jeff/014-1.jpg

The skates under the table are not permanent. They're only there to move the table for painting. The table actually rests on the heads of 6 inverted carriage bolts. On consideration, this foot arrangement will probably be inadequate in the long run.

Here's my kitchen table project. It consists of:
(4) geared Fulling steppers FL86STH80-4208BG7.5. 4.2a 3.3Nm holding torque when wired unipolar. (bought on ebay from a really smart and helpful guy, thanks George!)
http://i3.photobucket.com/albums/y58...k_jeff/011.jpg
(4) Deitech 2M982 (leadshine clone) 80v, 7.8a drivers, currently running half-stepping. Very helpful people, and extremely prompt shipping... from Hong Kong. (It takes less time to get stuff from China than Florida. Go figure.)
http://i3.photobucket.com/albums/y58...jeff/008-2.jpg
(1) PMDX-122 BOB
(1) homebuilt 57v power supply using rewound MW transformer, rectifier and 22,000uf capacitor.
http://i3.photobucket.com/albums/y58...jeff/012-1.jpg

(1) 1.3ghz compaq running Ubuntu 8.04 and EMC. The computer was a quasi-freebie. My teen son assembled it from parts. In return, I bought him a $30 pair of speakers from the local freecycle magazine. (The speakers sound very nice, and the computer works fine. Win - win. :) )
http://i3.photobucket.com/albums/y58...k_jeff/013.jpg

(don't be alarmed by the error messages on the screen... I'll get those sorted out. :) )

I'm not going to make excuses for the flintstone-ish (primitive) state of my kitchen table setup. The only unshielded bulk wire of the appropriate gauge I had on hand for the various interconnects was red. Thus, my power wire is red, my ground wire is red, etc. Kids, don't try this at home.

I am well fused, however. Each driver has a fuse, each 57v power wire is equipped with a 5a fuse, and the main power to the transformer is fused and as a bonus, equipped with a noise suppressor salvaged from the microwave.

And yes, after a day of wiring and head-scratching, I got it running last night. Yay! It's really quite impressive to see the heart of the frankenstein monster spring to life. The internet is the awesomest thing ever, which is a good thing because the drivers came to me without any documentation. They are similar enough in construction that I was able to use educated guessing and the Leadshine documentation to figure out their hookup.

Considering that yesterday, the sum total of my knowledge of this stuff was what I read here, I feel pretty good.

I have no doubt that as the build progresses, I'll discover the outer edge of the cheapskate envelope. When I do, I'll make adjustments.

...I wish I could find timber like that in your table in Florida. (sigh) I miss real lumber.

Your progress looks quite well.
Congrat's on the progress.

Sean

Jim,

Congratulations on your progress. You are doing a great job.

Keep posting on your progress and more photos.

Hi Jeff,

Very intersting setup, well done. May i ask what software r u using (the screen with the error msg's on).

Regards

John

It is Enhanced Machine Controller.

It's the open-source analogue to Mach3, but instead of Windows, it runs on Linux.

I'm still at ground zero on the learning curve, but what I see so far impresses me.

In my case it is running on Ubuntu 8.04

Jeff those motors will give you good service so far mine are still going strong and for the price that i have paid they do the job.

Hi Jeff,

Thank you. Could u give me more detail on the gearboxs pls, or even that George guy for pricing?

Regards

John

George built a router table using Fulling steppers but because he was initially suspicious of their reliability, he purchased two full sets when he built his machine. He has found that his extra set was unnecessary and sold his extra set on ebay.

I've heard that their cost new from China is very competitive.

http://www.fullingmotor.com/jsp/productshow.do?id=164

http://www.fullingmotor.com/jsp/productshow.do?id=172

Hennie, do you find that you need to use backlash compensation in your software?

Jeff,

If you use the springs that Gerald has to pull the motors toward the racks you will not have a problem with backlash.

http://i3.photobucket.com/albums/y58...jeff/001-3.jpg

Couple of new photos. I've sealed the table and added the mdf top. I also sealed the mdf, underside and edges. Mdf is quite porous, and without sealing, all the vacuum will be lost through the material. (Not that I'll have a vacuum system right off the bat, but probably eventually.)

http://i3.photobucket.com/albums/y58...jeff/002-1.jpg

What's significant about this photo? My shop is not very close to my house. I need an internet connection in the shop, but I don't want to bury yet another 100' long wire.
I already have a wireless router in the house, and the signal just barely reaches the shop. Unfortunately, because wireless protocols introduce latency, running a cnc machine requires wired (cat-5) ethernet connectivity.
My solution was to install a wireless bridge into which my shop computer could plug via ethernet. Ordinarily they are quite expensive, and not a function which is enabled in the average consumer router. However, Linksys built their WRT56G line of routers on a Linux OS. Since Linux is open source, Linksys was forced to publish their firmware. Clever developers took this firmware and created upgrades, the most widely-used of which is DD-WRT. The new firmware is a vast improvement, and allows the plain old router to function like ones costing 10x as much.
http://www.geeksaresexy.net/wp-conte...mainscreen.jpg
I bought a WRT54g router for $20 from someone on Craigslist, updated the firmware using the free software and it works great.
I bring this up because some of you may have the same problem.

I am using several 'game adapters' around my house. In areas where it is hard to get signal, I suggest 'invest' in a high gain antenna (or make an foil 'hat' in the shape of a parabolic mirror and 'point' it to your router.

I put a fairly long ethernet cable from my machine in the shop to the game adapter, and the game adapter where it can get the best reception (away from routers and other motors). It seems to be pretty stable. ... If I really want more connections in the 'shop' (webcam anyone?) a little hard wire switch can work nicely.

Just a thought or so!

Great progress Jeff!

Slow but steady progress
 

I love the summertime, but I don't find myself in the shop as often as I'd like.

We're getting somewhere. The gantry and y-car are both welded up and rolling. These plans are so freakin' awesome! :D

Between Gerald's plans and Castone's excellent laser cut parts and z-plate, I'm happy as can be. :)


Here's my computer...

http://i3.photobucket.com/albums/y58...ff/shop003.jpg
...but what's up with that microwave oven with a parallel port? A meal printer? A replicator?

Q) What does a person want in a control enclosure?

A) a box big enough to hold all the electronics and keep good airflow, as inexpensively as possible.

Wouldn't it be cool if you could get one with a window or two in the front to monitor the various LED's and equipped with a powerful fan which blows filtered air directly onto the power transformer? Wouldn't it be even cooler if it was free?

So far, it works nicely, but admittedly I haven't put any significant load on the steppers yet. The PMDX is mounted behind the window in the upper right. This was a pretty fancy microwave, so that window was the original location of the large digital display.

I'll put an e-stop in the front, and another on the left end of the gantry.


"Jeff's cost-saver build", right?

So, I asked the garage sale attendant with the pink hair "How much do you want for the old brown toolbox?"

He said "$12, but I'll take $10, it's full of stuff, I haven't gotten around to dumping it out yet".
http://i3.photobucket.com/albums/y58...ff/shop002.jpg

Kizmet? Serendipity? Whatever. I'll take it. It's a Kennedy model 526 still lined with felt and with about $200 worth of "stuff" inside, drill bits, cutting tools, taps, calipers, measuring tools...

Moral of the story? Never let a kid who would dye his hair pink run your garage sale.

Another garage sale find; $25 for my router. Runs fine, and at 9 amps, it'll get me started while I decide if upgrading to the Milwaukee 5625 or a spindle is the best option.
http://i3.photobucket.com/albums/y58...ff/shop010.jpg


One suggestion, there's gotta be a better solution to stop the gantry and the car. I used a 3" long section of the cutoff steel angle rail, cut the unground leg down to 1 1/2" and welded a 3" long piece of 1/2" x 1" bar to it, flush with the end of the newly-cut leg. After welding, I ground the welded face flat, and drilled and tapped that ground face.
Hopefully, this makes sense. I think there's a couple of things that could be done to improve the prox sensor/stopper block arrangement.

http://i3.photobucket.com/albums/y58...ff/shop008.jpg

I'm over $2000 in total cost... but not by much.

This is my favourite build! Brilliant! :D

Jeff,
Dont let the wife know you are having this much fun. It is supposed to be work right? Excellent progress and ingenuity !

Jeff you are the man! It looks great!

Leo, your parts have been perfect.

I come from a manufacturing background, and I am amazed at the tight manufacturing tolerances on the parts you supplied.

Very well done, and thank you.

It's ALIVE!!!!
 

Muahahaha!

No photos yet, my work area is still an embarrassing jumble of bailing wire and duct tape.

But it's working! The kids now understand what I've been doing. :)

No router mounted yet, but I did do the obligatory spring-mounted-pen doodles of the EMC logo.

Yay!

I have to say I'm really looking forward to see your BBB eating through stuff!

PICS PICS PICS!! VIDS VIDS VIDS!! Hear that like a Hulligans shout.

Your build has been very encouraging to me, thanks for that. Absolutelly Inspiring!

Francis

Jeff,
Whats wrong with duct tape? Nascar uses it! :) Although its 200MPH duct tape. Good Luck.

So far my duct tape appears to be only functional up to 500 IPM. :D

A couple of photos.

My cable management is suboptimal, but it'll do for now. I used 1/2" PEX pipe to keep the cables from dangling. Cable chains are a "phase later activity"

http://i3.photobucket.com/albums/y58...jeff/003-4.jpg

As mentioned elsewhere, I had to do some debugging of pinion set-screw issues, as well as teaching myself what the "touch off" function does in EMC.

The upper text was the best I could get, but by then my pen was nearly out of ink. :D

http://i3.photobucket.com/albums/y58...jeff/002-2.jpg

Sadly, I broke my $25 router by being stupid. Really bummed me out, too. The cables come out of the cap perpendicular to the shaft, and I didn't allow enough space between the router and the plate to account for them. When I over-tightened the router against the z-plate, I appear to have misaligned the rotating assembly. :mad:

I'll take it apart and see if I can do anything, but it's a long-shot.

I guess I have to go router-shopping. :(

I'm running 20t pinion, a 7.5:1 gearbox and half-stepping. So far the fastest I can go is 277 ipm without losing steps. I'm going to try it full-stepping. With that combo, at full stepping my resolution should be something like .002. I would be surprised if curves are significantly rough at that resolution.

Jeff,
I would think you would be better off in the microstepping range rather than full stepping. What is your interest in using the full step mode?

For the Deitech drive to emulate a Gecko's microstepping, the Deitech DIP switches must be:
SW5 = 1
SW6 = 1
SW7 = 1
SW8 = 0
which gives 2000 steps per motor rev.

Hi Jeff,

Are you shure the type of your stepper motors is "Fulling steppers FL86STH80-4208BG7.5"
I checked on the Fulling website and found only a direct motor without gears for this type. Can you give us a price for these motors?

Regards,

Bart

Jeff,

I found your link to the geared motors, overlooked it at first. :)
Could you give a price indication?

Bart

I got mine from Ebay, but the steppers are available from the usa distributor.

Nw cnc guy
 

Great build thread Jeff and congratulations on movement. I built a Joes 4x4 cnc over the winter and just recently noticed from the cnczone that some NW builders were building some MechMates so i am making a point of browsing the forum. I like that your using EMC which i have not had a chance to try yet.

Hi LS!

There are several northwesterners building MechMates.

I really like EMC, but I haven't found Ubuntu to be a complete solution. I haven't found any good Cad or CAM programs for it. Sheetcam is great, and I downloaded the linux version of it, but I haven't gotten it to run.

I spent the day surfacing my tabletop, but I found that my router clamp setup made the end result entirely unsatisfactory, so I spent the afternoon building a v0.2 clamp setup.

I'm hoping it'll be solid enough to make a v1.0 clamp from hdpe or aluminum.

I had no idea how much horrible, nasty dust mdf creates. Yuk.

As soon as I get logos applied, I'll post photos.