Looking for CNC Mill Part I

[PanzyPoof]

Group hope you can point me in the right Direction here!!
Looking For>>>
Any first hand info on any CNC Mill (Hobby size) approx 12"x12" bed.
Also interested in a CNC router table as well!
Would Strongly consider second hand if it's a fair $$
Hmmm! BTW
After looking at some finished units pricing I'll strongly consider a kit.
Also yap away inregards to the software ya use,
And any heads Up you can think of.
thanks

[planeman]

I suggest you consider these folks.

http://www.microkinetics.com

Planeman

[TedLarson]

Heh.......Once you find one....I guess you will be the guy to email when I need some parts cut....;)

- Ted

[DICKEYBIRD]

Pic attached of my homebuilt machine. I use CompuFoil, TurboCAD and AceConverter for .dxf to G-Code conversion.

Porter Cable 23,000 rpm trim router with 1/16" or 1/8" 2 flute carbide bits, MaxNC 3 axis motion kit, modified Dan Mauch platform with drawer slide XYZ slides, 12"x12" worktable with vacuum hold-down, 1/4" foamboard sacrificial table cover.

WARNING....BE CAREFUL....WHOLE NEW HOBBY!;)

[DICKEYBIRD]

Here's some ribs that were cut out recently.

[PanzyPoof]

Ya DICKEYBIRD now were talking:)
Don't have to be so big;) or built like it'll cut
battleship plates! BTW you are a craftsman I see;)
But yes something in this ballpark.
Or are there good plans/kits that yeld a quality machine?
BTW if you don't mind how much did you invest
:rolleyes:
Thanks

planeman, Nice tools at the link you provided!
but I'd have to sell the Harley to afford one.

Ted, ya better talk to DickyBird he's all setup
and waiting for you.

[uscra112]

http://www.machinetoolcamp.com/

I just ordered and received his "engineering package" for $100. It shows you how to build a stepper-motor-driven 2 or 3 axis machine in real detail, including complete bills of material. He also sells the motors, drives, interface cards, and other key stuff, and tells you where there are sources for the generic stuff. I was in the machine tool business for years and COULD have done all this myself but why bother when he's done all the detail work for you? For example, you supply the computer, he tells you where to download software, and he sends you a file that matches the software to your particular drive systems and machine. That's no small matter.

[DICKEYBIRD]

Oops, I forgot to give you some links; the 1st one listed is really cool for guys like us....he even has a 4 axis motion kit to do the CNC foam cutter I'm lusting after.:)

http://www.hobbycnc.com/
http://plaza.powersurfr.com/deanc/
http://www.geocities.com/crankorgan/
http://www.stepperworld.com/
http://www.cnckits.com/
http://www.desktopcnc.com/index.htm

I built mine about 4 years ago for approx. $650.00. There's a lot more stuff available now and if you're a scrounger, you can probably build one now for less.

It was built from 3/4" ply so it's not really strong enough to cut out battleship parts but you do need enough size & mass to dampen the router vibes. We don' need no steenkin' wobbley cuts, now do we?;)

[Tree_Magnet]

hey dickeybird nice router did you build it from plans if so do you know where i can get a copy?
i cnc my compact 5 lathe/mill and it works will but i only have 2 inch of travel in the y direction. i am finishing up my cnc foam cutter and should have i running soon (in a month). i would like to do a router next.

thanks Tom

I HATE TREES

[Tree_Magnet]

panzypoof sell the harley and the kid :D

[LuckyArmpit]

Reminds me of my dad. He had a toolmaker's lathe and a bridgeport milling machine in his basement. Made all kinds of neat stuff.

Dave...

[PanzyPoof]

YO TreeDart can't you modify that puppy to a bigger table:confused:
Ya must know some dude that'll machine up a bigger bed for you for FREE :rolleyes:
And then bring it over and leave it at my house so we can get some stuff cut.
You never have any Time.

[DICKEYBIRD]

Hi Tree_Magnet,

My machine was built by modifying the Dan Mauch circuit board drilling machine plan shown in the Dec. '94 issue of Nuts & Volts magazine. Dunno if the back issue is still available or not. Call 909-371-8497 or go to www.nutsvolts.com I think a more sturdy machine could be built using the plans offerred by Dave Rigotti or Mr. Kleinbauer in the 1st and 3rd links shown in my earlier post.

[PanzyPoof]

DICKEYBIRD thanks for the links;)
I've ordered a set of plans from
Mr Kleinbauer I like his playing field KISS no BS.
TreeStump is gonna help and were most likely build 2 @ once.
Just picked up some stepper motors 8of em
threw shaft design $5 ea

[DICKEYBIRD]

You probably ought to join this discussion group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/messages They are a great group that has some very knowledgable people available to answer questions.

Where'd you get the great deal on the stepper motors?

[PanzyPoof]

My guess is they Landed a container of the things.
So when there gone:confused: Saw approx 60 left.
If interested contact me and I'll hint there location. 7motel@interlog.con

[DICKEYBIRD]

Hint?? Why not just tell us where ya got 'em?

[PanzyPoof]

We'll OK guess the locals have all they need by now. Sayal Electronics 905-238-8640

[PanzyPoof]

Purchased the Plans from John C Kleinbauer.
$30 US And well worth it.
Build has been easy and straight forward.
I think this is a winner design,
Have Spent approx $130 in Home Depo and have Most of the Hardware and Wood. Picked up a Dremal in pawn shop for $40 and the Bearing required for $25
Building right along with the Plans(KISS)

[Hopperfly22]

So let me get this straight...
For less than $1000 you can actually build a CNC milling machine? Thats just awesome. Not that I'd use it because I can't even use Cad, but still I can imagine what I'd do with one lol.

[DICKEYBIRD]

Hey P/Poof....great job!:D You're stepping (no pun intended) into a whole new world of enjoyment (and at times frustration). Good luck and keep those pics coming as you progress. You'll probably end up with a trim router before long instead of the Dremel since they're much more robust and have tighter bearings (more accurate.)

Hopper: Yup, a lot less than $1000.00 in money but a LOT of fiddle time and software cussin'!;) I would suggest getting a cheap CAD program (some are free) and finding a friend to "show you the ropes." If you design or modify your own planes, you'll never regret the time spent learning CAD. Once you're up and running with CAD, CNC is not too hard. Heck, I've never had any training at all and I'm doing it!:)

[Zoltar]

Maybe interesting to all scratch builders....

CNC@HOME!

Just have a look at www.rcmodels.net/cnc

Real metalkits starting at 275 Euro, for compact, sturdy and usefull tool.

Completed homebuild machines based on this kit will endup between 700 and 1200 dollars depending on your personal skills....

Regards,

Chris

[jbourke]

Chris,

I was looking at your web site the other day and have considered ordering.

I'm a little unsure what else I will need to purchase. It seems that if I buy a CNC stepper/controller package from hobbycnc.com and use that with my own dremel and your metal kit, that I will then have all the components.

Is this correct? Can you review the packages at hobbycnc.com and tell me if they will work properly with your cnc router kit? What other expense should I know about?

Jim

[Erik Johansson]

I´d like to build a CNC mill that I could use to mill plugs for fibreglass fuselages (small ones for pylon). Isn´t there ANY drawing of a DIY-mill like the one pictured above with drawings online?

/Erik

[Zoltar]

Hello Jim,

Yes I saw this set also :

"Major Electronics Components Package Kit $225! "

"NOT included is a case and transformer. "

For this ad 60-75$

So you endup incl shipment at 300-325$

I can not review their electronics as I do not know it.

The steppers are oke- Vexta PH266-01A - (minimum 1Nm?)


Maybe you should also have a look at www.nc-step.de

I believe this is a real German quality electronics and

stepperengines. He is not too expensive....


If you combine such a set with a zoltar machine set 001-003-004

or 002-003-004 you are up and running. But if you have a lathe,

+ materials you can even you can start with set 001 or 002

too keep costs down. Please read on the website about the

different possibilities.

Regards,

Chris

[TedLarson]

Originally posted by Erik Johansson
I´d like to build a CNC mill that I could use to mill plugs for fibreglass fuselages (small ones for pylon). Isn´t there ANY drawing of a DIY-mill like the one pictured above with drawings online?

I am just learning about CNC mills myself....and don't know much yet....but, it seems to me that a mill which can do 3D cuts, would be much more complicated than one that could just do 2D cuts. Cutting a plug seems much more complicated than cutting out some wing ribs.

Panzy? Is it your plan for your new mill to do 3D cutting?

BTW....great photo!

- Ted

[PanzyPoof]

Ted
For now mainly Use plans That I've purchased Rescale to my liking then cut the Pieces from flatstock. 100% personal and for a few Friends.
My PBY needs wing Ribs so that's First once it's UP! I'm shure there be a List once word get's out
:confused:
Off to Home Depo for some 3/4Alun angle for the
Skates:(

[balsaman]

I plan on building one this winter. I have drawn up some plans for a 12x 24 table. Here is what I have so far: The plans are untried, untested, and as of now incomplete. I will send them to anyone who wants them.

Eric

www.e-zflight.com

[uscra112]

Balsaman - thats a nice job. But, having been in the machine tool building business most of my working life, let me suggest that you may want to consider making the long axis of the table run at right angles to the crossrail axis. This will keep the crossrail shorter and stiffer, so it won't sag as much when the weight of the router saddle is in the middle of the rail. Or build the crossrail as a box-beam, to make it as torsionally stiff as possible. Or do both. Also, having the table move on it's long axis will give a much better aspect ratio for it's guideways, which will minimize the tendancy to yaw as it moves, especially on direction reversals.

Are you planning to use some sort of steel anti-friction guideways? That's what it looks like you drew.

I'm going to do one this winter, too. May post a chassis design of my own if I get one I like. Wooden machine tools! The first machine tools were indeed wood - 1000 or more years ago. Then we started using cast iron in the middle 1700s. Steel weldments in the middle 1900s. Epoxy-granite in the late 1900s. Now here we are back to wood, but with computers on them, no less ! I'm thinking of making my guideways of oak, (from Home Depot), just to see if I can make it work! :)

[balsaman]

USCRA,

Thanks for the tips. I designed it this way because it fits in my shop better this way. I don't anticipate any troubles with rigidity or sag. I work as a maintenance electrician for a large autoparts manufacturer. Automobiles change quikly and as a result, our equipment gets modified/replaced regularly for new model changes. The equipment gets scrapped, and me, being the scrounger that I am, am over there scabbing the cool stuff off before it goes in the scrap. I have enough linear bearings and the matching hardened steel rail to make the cnc router. These things are almost friction free, and there is NO freeplay whatsoever....we are talking none. The rails are also very rigid, which will make the "bridge" very rigid as well. I also found some sweet 1/2" ACME threaded rod.

here is a pic of the linear bearing:

Eric

www.e-zflight.com

[uscra112]

Balsaman - that's good stuff, alright! Great that you have such a source. Those will be PLENTY stiff enuf ! The bearing you posted the picture of is worth $200-400 buckadingdongs, new, never mind the rails!

I used to have the same access to leftovers at my last job, but now I work for a CMM company (Zeiss) and they're all air bearings and band drives . . .

Happy trails - there's gonna be two good hours of flying weather tonight, so work has had me for today.....
;)

[Scratchbuilder]

I'm really gonna reach here with this one, but why hasn't anyone checked out the H2O, pressure cutters? The foam will get wet, but it won't hurt it{it'll dry out}. No worn tooling to replace or resharpen...cuts as fine as a thin stream of high pressure water can, and water is cheap. I've seen these set ups cut thru high grade{5000/6000 series aluminum} that's a 1/4" thick and it'll leave an edge sharp enough to shave off of...nearly. Question is just how much psi will it take to make a clean consistant cut thru roughly 2" of OC pink foam. I'm not even going into lasers. Next question is how would cutting wood be with this...if a fine enough stream could be shot and done quickly at that, there shouldn't be too much of a warpage problem...I'm thinkin.

[balsaman]

I haven't looked into this. I personally am concentrating on making one that cuts....period. If I am successful, It's a matter of replacing the dremel tool with???? For me, making the x, y, z, table work is enough challange for the time being.

Eric

www.e-zflight.com

[PanzyPoof]

I was show one of these machines @ Steen Aerolab
Home of the SkyBolt:D (My Baby's in the Garage)
And it was huge! Used to cut metal 4130 into fittings. Hmmm I used a hacksaw.
The Nossel is the size of a Hair and Huge $$K .
Water filter system anouther major problem. And the Noise is real Bad. If I recall a fine median is injected into the jet a few mm from the tip. Where it accelerates to the speed of sound
in about 7mm. Ya Nuts.
Nice desired Cut since the surrounding metal is not hardened as with Laser. Big Job keeping it operational.
For my Cutting damm close is good enough for now
Pass 220 paper once Done;) I'm shure later on I'll
learn more see and build a nicer machine. As we all would like.

[Zoltar]

The Dremel or similar is good for a start in this CNC hobby.

As a replacement for electric tools I've been looking for air pressure - hand- tools.

Its used mostly in car bodyshops and they run on pressed air.
and are build rigid, take up larger tools too.

These tools sell at 30 to 40 Euro overhere.

The only disadvantage is the sound and you need a compressor.

BTW-- Balsaman love your guide-balbearing roller guide system I guess you've got it sorted for a durable machine !

regards,

Chris

[PanzyPoof]

Picked up some more parts. Easy to find just running around to get em.

[PanzyPoof]

Here is a Skate BB end .It's very smooth

[uscra112]

Yah, PanzyPoof is right. I once researched these with a thought toward adding one to the aerospace machining facility I was tooling up. It takes something like 50,000 PSI to make them work, so the pump is enormous and costs $100K. The jet doesn't HAVE to have an abrasive in it. For soft materials like wood you use plain water, but it has to be very clean. The jet is very dangerous. After it goes thru the thing you're cutting it's still good for taking off an arm at the elbow. But y9ou'd be surprised where you find these in use. They cut up chickens with them. Clothing manufacturers use them to cut fabric 50-100 layers at a time. Plastic moulders use them for sprue cutting and flash trimming. But for us? Forget it.

[crankorgan]

Hi Gang,
I am 50 years old! I used to make gliders back in the
days when there were rudder only rigs. My hobby these days is
CNC. I design and sell plans for dirt cheap CNC machines. I have two machines that I recommend for cutting model plane parts. The
7th Sojourn and Morph. It takes very little machine to cut balsa so I went way cheap! I was hoping that RC people would realize they could exchange GCode files for cutting planes. I put many hours into this field. Please feel free to ask questions. The Dremel Multi Pro will cut balsa like butter. Use a $7 carbide three or four flute cutter. A good DC motor will also cut balsa. With all the foam cutters out there. I decided to make some machines that will do the other parts. There are now several people making
my machines so they can cut balsa parts.

Cranky

[Bob H]

>I am 50 years old! I used to make gliders back in the
>days when there were rudder only rigs. My hobby these days is
>CNC. I design and sell plans for dirt cheap CNC machines. I have >two machines that I recommend for cutting model plane parts. >The 7th Sojourn and Morph.

Crankorgan, Where can we buy/see your plans?
Bob H

[balsaman]

His web page is here:

http://www.crankorgan.com/

Eric

www.e-zflight.com

[crankorgan]

Hi,
My website is:

www.kleinbauer.com

or

www.crankorgan.com

I joined this conference to answer questions and to discuss the steps or equipment need to CNC model parts. I
am not here to push my plans! My plans were the result of a
vision of people exchanging plans for models as GCode-DXF
or PLT.

Cranky

[DICKEYBIRD]

Originally posted by Bob H
>Crankorgan, Where can we buy/see your plans?
Bob H

In case Mr. Kleinbauer's not online, here's his GREAT website. (Also posted in my post upthread a ways.)

http://www.crankorgan.com/

HTH:)
Milton Dickey

(Oops, Mr. K wuz posting as I wuz typing!)

[crankorgan]

Hi to Zoltar and DickyBird!

Nice machine DickyBird. What bit do you use with your machine. Zoltar, you are the guy with the CNC machine kit?

Cranky

[uscra112]

Crankorgan, you're my kind of guy. Great stuff. What WOULD we do without the internet? Gawd I'd be bored. . . . But I'm going to do my all-wood machine tool anyway, just for grins.

The thing many of us modelers aren't good at is the electronics part. I USE computers extensively, but I'm not hot at the nuts and bolts of the bloody things. You apparently have been scavenging plotters for axis drives and controls. Do pen plotters have the oomph to do anything useful? What are the best ones to scrounge for? How do you get them to slow down enough to become a router? (Gear the motors down?) etc., etc. Is all this stuff in your plans packages?

[crankorgan]

uscra122,
I use hardware store parts in most cases. If you find
a plotter, you can use it to draw the parts on the balsa. Then you
can cut them out. A plotter has problems just moving the pen!DXF files can be printed to a plotter as a PLT file. Most of the Windows versions won't let plotters work. This is why I combined CNC machines and Plotters in my designs. There are lots of ideas kicking around. I am at the point now I can start helping people. I got in over my head there for awhile. Those 16 hour days are killers! I spent seven days a week for two years designing machine. I didn't even know if there was a market. I liked RC when I was active. I figured there must be a few soles out there. I got laughed at by the Bridgeport guys. I hear Bridgeport closed up! Maybe they should have produced simple machines to cut out RC parts.

Cranky

[jbourke]

Cranky,

I'm glad to see you here! I enjoyed browsing your website a couple of weeks ago.

This thread is really interesting because I've been looking into making my own CNC machine for a couple of weeks now. I created "The Workshop" forum to give me a place to post some threads on my experience.

Coincidentally, I was planning to contact you and Zoltar and a few others to see if you guys would be intersted in talking about CNC in this new forum. In fact, I'll just move this thread to get things started.

This is a really exciting new direction for me in the hobby. I can't wait to get my first CNC machine set-up.

Jim

[balsaman]

Cranky,

I have a question. Will the 50 oz. steppers be sufficient to cut heavier woods than balsa? I may want to cut mdf, etc. in the future and only want to build once. I have seen 80 and 100 oz motors out there. Should i splurge on the heavier drive board and larger motors or is it not necessary.

I plan on using a rotozip or small router for the cut motor.

I don't want to cut at 2-3 inches per minute.

Eric

www.e-zflight.com

[DICKEYBIRD]

Originally posted by crankorgan
Hi to Zoltar and DickyBird!

Nice machine DickyBird. What bit do you use with your machine.
Cranky

I built mine by modifying the plans shown in an article by Dan Mauch in the Dec. '94 issue of Nuts & Volts mag. I just used his wood machine plans and used the 3 axis motion control kit from MaxNC (stepper motors, driver card & software) I beefed it up a bit in the Z-axis bridge and used extra drawer slides on the Z plus fitted a Porter Cable 23,000 rpm trim router.

If I had it to do over (and I may just do it again!) I'd use your plans.:D Mine has trouble with the X/Y table moving up & down at the limits of travel causing cutting depth inaccuracies. Yours is much simpler and more rigid.:) I shouldn't complain about Dan's design though since his was designed to be a CNC circuit board driller where Z-axis depth accuracy wasn't that important and I chose to run a router with it. It does great for 2 1/2D stuff in balsa and ply.

I would like to do another one with maybe 24" to 36" X travel, more Z accuracy, learn 3D CAD and toolpaths so I can rough out plugs for wings & fuselages....then a 4 axis foam cutter....a medium size CNC mill.....oops!....I wouldn't have time to build any airplanes!;)

[uscra112]

Cranky -

Just as I guessed - plotters can barely get out of their own way.

And Windows plotter-drivers are all keyed to the applications they sevice, not to plain old ASCII files like DOS drivers were.

What with the software now on the Web for a couple'a Benjis that'll run G-codes, you hardly need to fuss with using plotter software anyway.

Have you had results using plain old threaded rod for leadscrews? For the accuracy we need, that should work fine, and they'd be so cheap that if they wear out you just replace 'em.

Y'know, what we need is somebody testing and reporting on kits that have the stepper motors, controllers, cabling, and software all bundled for us to install on a structure we built ourselves. There's any number of vendors on the Web, but who knows who's got the right goods at the right price, and who doesn't? I mean, I was IN the machine tool business for years, but I myself am in the dark about these vendors. A nice website doesn't guarantee the goods. jbourke - I think you might be heading in that direction, yes?

[crankorgan]

Balsaman,
50oz motors into a 1/4-20 threaded rod gives you
100 to 250 pounds of force. Torq goes down the faster you run the motor. I would rather own a whole machine than just a great
motor system. With all hobbies, you should work your way up. That's how you learn. A friend of mine built a $800 RC plane rather than buy a trainer. He was afraid to fly it! The last I heard
it was locked in the trunk of an old car in his garage. He kid got a hold of the plane. Now parts are missing. People don't like starting on the bottom. The funny thing is you pickup so much more. Sometimes you even come up with a new idea!

Hey! is anyone using a flatbed printer to print layouts right on the balsa? and is there a synthetic material that replaces balsa.
Some kind of plastic?

Cranky

[uscra112]

jbourke -

If you're going to "move this thread" - how do I make sure I can still find it?

Gottsta run - back on Monday.

[crankorgan]

uscra112,
HobbyCNC has complete motor systems cheap. I bought my first motors there. Lots of stuff on Ebay. I warn people about spinning the motors first. Just like RC, once you
spin the motor, the building seems to stop. Motors are the easy
part!

Cranky

[crankorgan]

Dickeybird,
Even if your machine is not perfect, I bet you learned alot! I stayed away from drawslides. Lots of people mention them. I went with roller blade bearings. They have dust caps and you can buy them at most sports stores. I bought the $32 ones then I bought the $16 ones. The cheaper ones are just as good. Rollerblade bearings are made to be around dust. My machines also use the guide and way methods like a milling machine uses.
These are also easy to keep clean. Threaded rod works great with a nylon,Delrin,Plastic or a nut made out of a chunk of white plastic (UMB?)cutting board.



Cranky

[crankorgan]

Hi,
If we move let me know.....I tend to talk to myself as it is!

Cranky

[balsaman]

Cranky,

Thanks for all the help! I am using 1/2"-10 acme threaded rod. If you say 20 pitch = 100 lbs, then my 10 pitch should be around 50 lbs. That's quite a bit. I think I will get this kit from stepperworld.com then:

http://209.41.165.153/stepper/sp3HT.htm with the FET3 upgrade for more current. Or should I forget the upgrade? the sp3 is good for 1.25 a per phase.

Or do you recomend the 83 oz system from hobbycnc.com?

Way to many choices.

Lots of guys use fanfold foam as a substitute for balsa these days. Have a look at the foamies section. Also coroplast, which is a tough coragated plastic.

Eric

www.e-zflight.com

[DICKEYBIRD]

Originally posted by crankorgan
Dickeybird,
Even if your machine is not perfect, I bet you learned alot! I stayed away from drawslides. Lots of people mention them. I went with roller blade bearings. Cranky

You bet I did! What an experience. The MaxNC .dxf/G-Code conversion utility was all I had for 3 yrs. It WILL NOT accept anything but true blue ACAD files. I draft in TurboCAD....I had to import a T/CAD .dwg into a borrowed copy of ACAD (YUCHH!!) save each part out as a joined polyline .dxf, convert each file individually and then merge them together in a word processor to get a cutting file with 7 or 8 parts cut in the same run. Then I found Ace Converter...does it all in one step! For FREE!

Next machine will definitely have roller blade brgs. as you suggest but for now, I'm cutting some good parts to go in my planes.

[crankorgan]

Balsaman,
Alway check with the guys you are buying from. Then
if there is a problem you can get your money back. Both Dave and Russ are honest guys. 1/2-10 rod, sounds like over kill for cutting balsa. I have no experence with threaded rod that thick or the torq needed to move the threaded rod. I hope you are going to be cutting other things.
The reason I use 1/4-20 rod is. It's cheap, you can find cheap qualty rod and replace it later with better. It gives you lots of power using small motors. And the payoff of being able to tap and make your own drive nuts. There is almost no backlash at all when you use a 1/2' thick pice of nylon-Delrin or cutting block. As the thread gets coarser the nut can get sloppier. Then you have to spring for antibacklash nuts Do you own a 1/2-10 tap?

Cranky

[crankorgan]

DickeyBird,
I used the free version of Turbocad from the internet. I
then found a version of it for $29 at Staples. So I bought it. I use
an old version of Kcam to convert to GCode. Converts the DXF to
GCode. Lets me see where my part is going to be based on the size of the bed. I can also do offsets in KCam. There is also a Find and Replace. I use this when moving a GCode to a new machine. The new version of Kcam stops working after 30 days.

What cutting bits do you use? I use four flute 1/32 ToughCarb.

Cranky

[DICKEYBIRD]

Originally posted by crankorgan
DickeyBird, What cutting bits do you use? I use four flute 1/32 ToughCarb.

Cranky

I use 1/16" 2 flute carbide router bits from Eagle America (Although they measure .055" od!) I don't have tool dia. offsets in the MaxNC control software so I have to draw in all the offsets myself...hehe, good for the soul! Been using the same bit now for 3 yrs.! (Knock on wood!) I use 1/8" 2 flute bits for ply.

[crankorgan]

DickeyBird,
At least you used Turbocad! I used to use a DOS
editor and a quickbasic program to see my plots. Things are
getting better all the time. I also got the idea to do hop and
skips in my gcode. This would leave tabs on the parts. The tabs
would keep the parts from shifting during cutting.

Cranky

[PanzyPoof]

jbourke
Go ahead and move this thread if ya want!
The Workshop!!! Should be a HOT Area:cool:
The rest of the Zoners will catch on.
Whow! Zoltar and Crankorgan :D both sides of the Pond same thread... be nice;)
Say Cranky Hope you're not Ticked with me posting some Pics of my Progress building the & 7th Sojourn. Won't be leaking any copy written materials. Just say NO!
Just glued & mounted the Trolley drive motor base.
Ya motors they were $5 each :D
The Channel Stock y/Z Frame I found is a little diff from what you specify, I see only the gib size will be affected! Do I see All?
Off to Build the Trolley :eek: so far it's been easy and the most $$ part's been the Channel Frame (4'@$9 per Foot):D

[balsaman]

I have access to a 1/2-10 tap. This is ACME thread, which is very acurately cut, not rolled like threaded rod. I got it free, so I am going to use it. I will post some pics once I clear a spot on my workbech and start.

Eric

www.e-zflight.com

[DICKEYBIRD]

Originally posted by crankorgan
DickeyBird,
At least you used Turbocad! I used to use a DOS
editor and a quickbasic program to see my plots. OUCH, That musta' been painful!

Things are getting better all the time. I also got the idea to do hop and skips in my gcode. This would leave tabs on the parts. The tabs would keep the parts from shifting during cutting.

Hmmm, great idea; I've been using little scraps of 1/16" balsa ever so often to insert down into the cuts behind the bit as it progresses (along with my home-made vacuum table) I also stack 2 or 3 pieces of balsa, stuck together with little squares of 2 sided sticky tape (INSIDE the cut line of each part) so that I can make 2 or 3 of each part at a time for duplicate ribs and the like.

[crankorgan]

DickeyBird,
A friend of mine bought a service box kit. The box the
plane sits on when you start it. The box has the battery in it
along with a meter and gas pump. I helped him modify the box for his car. Well anyway! The kit was veveral sheets of thin plywood. The parts were watercut. The guy left the parts inside the sheets of plywood. I could see where the water was turned on and off. Rather than waste time knocking the parts out he left them inside the plywood shell. My friend had to cut them free! Very neat idea! I figured having the bit hop and skip will produce the same effect.


Cranky

[crankorgan]

PanzyProof,
You seem to be building a double trolley? Or two
machines? Or maybe you are going ahead and adding the bottom optional bearings! You confused me there for a second! Don't worry about posting pictures. I find for every sale it costs me, I get two more.
Cranky

[crankorgan]

Balsaman,
I do buy 1/4-20 threaded rod from a local tool suppler.
Under a loop it looks tighter than the store bought threaded rod. Comes with oil on it. It looks jet black. Costs $1.50 for six feet. When I use this with a block of 1/2" Delrin, I can feel no slop! Let
us know how you make out. What are you using for a nut?

Cranky

[balsaman]

Cranky,

I am not sure what I will use for a nut. I was going to use oilite bushing material, but now I may use polypropalene plastic, since you say it works well. I will let you know. For right now I am still gathering materials, as I need to finish my current project (airplane) to make some more room.

Eric

www.e-zflight.com

[planeman]

I’ve been following along on this thread about CNC routers for cutting out balsa parts. I’m not there yet but I will be soon. It is just that it takes me so long to make a model. I’ve been working on my first one for 37 years now and I’m about half finished.

First of all I needed to cut some pieces. Wanting to do it right, I went to Pennsylvania to dig some iron ore – they have some of the best – even though I had to quit my job, lost my family, and I still owe Motel 6 $2,487 for the room. Then I came back and built my own smelter and cast the iron and steel parts for the saw. Now that I had the castings, I had to scrounge around for a good used metal lathe and mill to machine it with. After a few years of assembling the necessary tools, I set to work building the saw. All was going fine until I came to the bearings. I was considering building my own ball bearings until some friends convinced me that maybe babbit bearings would be good enough. Then I realized I didn’t have any copper, tin and antimony. I grabbed the shovel and spent 6 years out West digging enough ores to make the bearings. Fortunately, I had my smelter and was able to have the bearings cast about 6 months after I got back. I don’t answer the door now as Holiday Inn is looking for some three grand I owe them. Anyway, I machined the bearings and set everything up for the electric motor. I still had some iron and copper ore left over so I started in on building the motor. The wire insulation threw me until I came across a plastics plant going out of business. It only set me back $ 200,000 and the insulation was really great. Finally I sharpened my saw and mounted it on the arbor. Then, hesitantly, I hit the switch and …the damn thing ran!

Now I sawed those parts out but I need to drill a hole. I’m out of iron ore, so It’s back to Pennsylvania.

When I finish this plane, I think I’ll give this CNC stuff a try. I wonder if it will speed my plane construction along any.

Sincerely,

Planeman

P.S. The other day someone showed me this new tool for cutting balsa. It’s called a razor blade. Think I’ts any good? Looks too simple to me.

[uscra112]

Planeman, you obviously agree with me that the destination is just an excuse for the trip. :)

I used to road-race motorcyles pretty seriously. That hobby cost me a lot of money and time, but I had the incentive to teach myself more about engineering subjects in depth than I EVER learned in school. Has stood me in excellent stead in my current career, which I would doubtless not even HAVE if I hadn't learned all that stuff. So it worked out for me both ways - I had fun, and I advanced from a college dropout to a level where many real engineers are jealous.

N.B. Before I was old enough to own a motorcycle, I built planes - lots of them. I could tune a Baby Bee to a fever pitch at the age of 14, and I won a few HLG contests, too. That's where I learned to be an autodidact in the first place.

Keep it up, everybody.

[DICKEYBIRD]

Originally posted by uscra112
That's where I learned to be an autodidact in the first place.


You know, for years I yearned to be an autodidact until I realized I wasn't sure what an autodidact was. I then applied myself long and hard to the task and finally taught myself what one was. In other words, once upon a time I couldn't even spell autodidact; and now I are one!;) ;)

[Zoltar]

>>>Whow! Zoltar and Crankorgan both sides of the Pond same thread... be nice<<<

Yes, Panzy, this could become a interesting thing.

---->>Different aproach on themachine design, same target.<<----

We will see.

Anyway if someone is interested going with me to the workshop for some actual work.....:) Cranky?

I think it should be a thread seperated in CNC construction , electronics and a separate thread for the software part on CNC.

It should cover : what are the general problems rising in building a CNC machine, the electronics and with the used software.

Anybody interested?

Chris

[PanzyPoof]

Pick a Good name!
Go for it;) I'm here to learn!!

[DICKEYBIRD]

Originally posted by Zoltar
[B
Anyway if someone is interested going with me to the workshop for some actual work.....:) Cranky?

[/B]

Here's some actual work I did....I helped a friend with a replacement wing for a Something Extra. He smushed his wings and wanted a new tapered wing with straight L.E. ala Edge 540 so I designed it in CompuFoil and TurboCAD and cut out the ribs for him . The ribs were cut to use the original alum. tube spar with lite ply doublers and since the wood he gave me was hard (HEAVY) I cut out lightening holes in the ribs as well. The thing actually flew great!

[DICKEYBIRD]

More actual work...."Twin Lizzie 2" nacelle/wing saddle blocks cut from 1 1/4" soft balsa block. I had to go to a 1/4" dia. router bit to get one that was long enough to allow the 1 1/4" depth of cut....note the little 1/4" blocks placed into the cut to prevent the part from coming loose and being damaged as the cut was finished. By the way, it did fit the wing perfectly!

[crankorgan]

Hi Group,
I am only hanging out here! My intent is to answer questions about simple-cheap easy to build CNC machine. As for doing real work! I got two years of 12 to 16 hours a day invested in my hobby. I retired at age 37, I am now 50. My hobby consumes most of my time. During my breaks I surf the internet. My other hobby is walking at least 50miles a week. Got to walk! Too old to run.

Cranky

[balsaman]

P.S. The other day someone showed me this new tool for cutting balsa. It’s called a razor blade. Think I’ts any good? Looks too simple to me.

Razor blade? That has a cool factor of zero. You gonna brag to your inlaws at Christmas..."Hey look, I can cut balsa with a razor blade"? I don't think so. :D :D :D

Besides, it's too quiet. ;)

Eric

www.e-zflight.com

[balsaman]

Cranky,

I tapped a couple holes in that delrin. You are correct. No slop. Thanks for the tip!

Eric

[crankorgan]

Balsaman,
Sill put some oil on the leadscrew. I still want to buy a
pulley tap so I can tap a thicker blocks of Delrin. Some people are
getting good results with cutting block plastic. Cutting block plastic is more like nylon than Delrin. It tends to provide a tighter nut on the leadscrew. I bought a large 5/8" thick block on Ebay. My tap just make it. The pulley tap is longer.

Cranky

[Zoltar]

>>Some people are getting good results with cutting block plastic. Cutting block plastic is more like nylon than Delrin. It tends to provide a tighter nut on to the leadscrew
Cranky

Hello Cranky,

First I have to say that you have given me personally (and I guess like many others) a lot of inspiration to design a personal CNC machine!

Thanks a lot!

Butt can you tell me what you mean by Cutting block plastic ....?
Is this a product name.

Regards Chris (Zoltar)

[crankorgan]

Zoltar,
People who build my machines sometimes improvise. Rather than wait for their Delrin to arrive, they keep building using a hunk of white plastic cutting block found at the kitchen
section of a store. I think the plastic is UMB. Taps like nylon! Takes several taping passes. Srinks after taping for a tight fit.
Delrin taps cleaner. Its self lubricating properties makes it
perfect for light loads. Don't for get the oil! Without the oil the nut
can heatup and grab the leadscew. PVC also works.

Cranky

[DICKEYBIRD]

Funny story (to me anyway):

When I was reading about and collecting parts for my CNC router (4 yrs ago) I wasn't even using the internet at all, had no connections with CNC users, hadn't even seen one operate....I was going strictly by Dan Mauch's N & V article alone. He mentioned "PIC Industries" in his article for better quality leadscrews & stuff if the builder wanted something better than all-thread rod and hardware store nuts. I was so naive, I was truly worried that the stepper motors would turn so fast that the hardware store gear would wear out in no time or would seize up if I didn't really stay on top of a cleaning and lubing ritual. Therefore, I bought PIC Acme threaded stainless steel leadscrews and their fancy "unobtanium" plastic low friction Powernuts. Imagine my embarassment when I finally got the thing up & running and saw the speed of my stepper motors!:o I must admit that I don't regret buying decent stuff but I couldn't have been more wrong about how fast this stuff operates!

[crankorgan]

DickeyBird,
From what I see you have done well! You saw the potential. There are people out there who overbuy. They buy a $800 motor system with no machine to hook it to. They spend weeks tweaking the motor adjustments and power supply. Twelve inches per minute might seem slow, but it beats laying out and cutting out a part. In many ways my homemade machines nave paid for themselves. I made a nice profit milling and selling circuit boards. It was during this time several RC guys asked me for a machine to cut plane parts. I then produced three designs. CNC is now in every field. My vision is people exchanging DXF and GCode files. Maybe a CD of airplanes. You could print them out-or have the machine cut them out. The software is coming down in price and so are the machines. I real tinker can produce a machine for $75 that will cut Balsa and plastic. Zoltar has produced an inexpensive machine for people who just want a kit. I looked into selling a kit several times. I found selling paper with words on it to have more profit.

Cranky

[PanzyPoof]

As to the PVC board material.
I visited a plastic warehouse, by the counter was a cutoff bin. Found and picked up
10sticks 8"x10"x1/2" of this board material.
Took the guy a min to identify what I selected,
Sad it was THPE (hmmm got that corect) high density something. He explained it machine's very well better then delrin...PVC. Taps easily.
Very smooth finish kinda waxy, Scars easily
:rolleyes: White, very rigid, guite $$ like over $10 per ft.:mad:
So what I was holding $30can Hmmmm beer money:cool:
As to working it have only cut up a couple of Beds out, on the tablesaw and it cuts real nice.
You can feel the blade working but not loading up as I was expecting.
Soooo Onward:D

[PanzyPoof]

Oh YA Onward will be real slow.
While cutting some Balsa on the Dremil Tsaw,
figured I needed a longer rip so moved the machine to the edge. Well ya it vibrated itself over in the middle of a pass and nailed my Index @the top joint. :( 3 stiches! should be able to pick my nose in a month;)

[crankorgan]

PanzyPoof,
I use PVC for fixtures and all kinds of things. Any plastic you can Sand-Drill-Glue and tap is good to have around. I used to call grey PVC proto-plastic. I used to use the PVC for models and proto types. Then I just started using the PVC instead of aluminum and steel. I just love visiting my local plastic place. I always call them first. They gather up the PVC cut offs. I put a place on my links page of a guy who sells PVC on Ebay. He sent me 37 pounds of 1/2" and 1/4" PVC sheets as gratis.



Cranky

[DICKEYBIRD]

Originally posted by crankorgan
DickeyBird,
Twelve inches per minute might seem slow, but it beats laying out and cutting out a part.

Man I WISH I could cut 12" a minute! Mine will do 8 - 9" max (when cutting) but I've found that it will skip steps at odd times and ruin a sheet of parts so I just take a deep breath, relax and watch it do it's magic at 6". She never, well almost never anyway, skips at 6" per.

One of these days I hope to either raise the supply voltage and change dropping resistors to get more speed & power or just start over with a new machine. Ahhhh, so many toys, so little time!:) :)

[crankorgan]

DickeyBird,
If you are using a computer supply, put a 5 ohm 10watt resistor on the five volts. (Black to red) This causes the 12 volt line(yellow) to go up to 11.6 volts or so. The load on the five volt line also helps the supply regulate better.
Make sure the spindle motor is plugged into a different line in the house. Use an extention cord if you have to. The spikes from a carbon brush motor can ride through the supply and cause extra steps in the controller at certain times. Most missed steps are caused by running the motor too fast or with not enough current. (too high a value of resistor!) It could also be those fancy drive nuts are too tight for the torq of your motors. Six inches a minute is still to fast for catching a mistake. A $7 bit is gone before you can say:"Why is it doing that?" I cut my circuit boards at 4" to 6" to prevent noise. The faster the cutting the faster the Dremel is set and the higher the noise. I still want to switch to a flexshaft driven by an AC motor with stepup pulleys.

Let me know if you cut out a part using Hop and Skip cutting.

Cranky

[mralston]

How dimensionally stable are the cutters made out of MDF? Do you coat them with something to keep the moisture out, or does it even matter? I'm getting ready to build a CNC foam cutter and can't decide on the slide material. I found a place that will sell small quantities of Aluminum plate and extrusions at reasonable prices, but am wondering if I can save some money by using MDF.

Mark

[DICKEYBIRD]

Originally posted by mralston
How dimensionally stable are the cutters made out of MDF? Do you coat them with something to keep the moisture out, or does it even matter?

I built mine from 3/4" MDO plywood (I think that's what it's called)
It has a layer of what looks like brown paper bonded with waterproof resin to both sides. Signmakers use the stuff in large quantities. It's very smooth and flat; takes paint very well and as far as I can see, is very stable. I "wrapped" all exposed edges of the ply with 1/4" pine, glued & bradded on. I painted all surfaces with brush on hardware store grey "epoxy" (wasn't 2 part) It has held up very well.:) :)

Good luck and let us know how you get on with your CNC foam cutter AND SOFTWARE. I'm lusting for one, but even after reading all the material that's out there, I'm not confident enough to cough up the buck$ and time.

[crankorgan]

mralston,
MDF only needs three coats of acrylic paint to seal it. Go with Grey. Other colors are too dark. I no longer screw MDF together with wood screws. I tap it with a 1/4-24 tap and use bolts to hold it together. MDF machines are very strong and accurate. MDF is only a material. Accuracy and strength come from skill and good design.

Cranky

[Zoltar]

Good day, Cranky!

Why dont glue it ?

Use a few small nails to hold it in position and use glue for assembly, and a glue clamp pressing it tight together.

--Pull out the nails when finished--

Eventually-if realy needed- use a bolt as you described on one or more threatening heavy loaded spots.

My experience is that glue takes up loads within contructions nice and even.

Regards,

Chris

[crankorgan]

Zoltar,
I like glue! The problem is sometimes you want to redo a part later on. Using bolts gives you a second chance. I have no problem with using glue when you are sure! I am never sure, always making changes. I am working on a large router made out of MDF. Looking to stay in the $125 range like my other designs.
I can't afford to use glue at this point. I always recycle my plastic and MDF boo boos. Glue make recycling parts harder.



Cranky

[PanzyPoof]

Main rails.
Hmmm just a tad out on the rails.
Not parallel 100% = not parallel 100%
I think I'll not cry about it and move on.
For what I plan to do I don't think it'll matter
much.
Picked up some Alum flat stock and will use it for Gib beam.
I'm useing both on the MDF Frame, Glue and screws.
Will only paint the steel pipe rails. That'll help in above delema:rolleyes:
Got some Mil specks primer one thin coat is all they get. Rust Lick may also work?

[uscra112]

Cranky - what do you mean by MDF? Is it that sawdust-and-glue sheet ( I use 3/4") that you can buy in Home Despot? I've used that stuff myself for things that I wanted to be accurate and not warp. My My foam-cutting bench has a vacuum chuck made out of it. Works excellently. My own router will be made out of it. But it does have to be sealed. I used polyurethane.

You can make a leadscrew nut by coating the screw with mould release and casting a nut arund it with a strong, slow-setting epoxy like Devcon 2-Ton or JB Weld. This is a process we actually used for machine tool repairs. It worked nearly as well as bronze, and cheaper and one H of a lot quicker. If you want to do it in metal, get a block of that low-temperature bismuth alloy from Micro Mark ( McMaster-Carr also sells it.)

[crankorgan]

uscra112,
The MDF I buy looks like brown cardboard. I use grey acrylic latex. MDF can be taped with a 1/4-24 thread. Feel free to
try it. You can even coat the threaded hole with urathane for more ummmph.

I only use cheap 1/4-20 threaded rod with a homemade tapped Delrin nut. Gas pipe and rollerblade bearings for my
X and Y axis. The new machine is a hoot!

Cranky

[crankorgan]

Hi Group,
Let me make a correction. I use 10-24 bolts to hold together 3/4" MDF. I said 1/4-24....

Cranky and Tired

[uscra112]

Cranky - I'm still out to lunch on this MDF material, I guess. Cardboard? You mean like corrugated? Where to you buy it? Is it a plastic? Sounds like it, if you can tap a #10 thread in it. . .

[DICKEYBIRD]

Originally posted by uscra112
Cranky - I'm still out to lunch on this MDF material, I guess. Cardboard?

MDF is "Medium Density Fiberboard" like particle board but farther up the food chain, ie; better quality.

[PanzyPoof]

uscra112
Here's a cross section 3/4"
Hit Home Depo In the Ply Handy cut section.
They will cut for you too.