blackFoot 4x8 CNC Machine Demonstration

[@PatrickHoodDaniel]

Thanks! Yes, you are correct. The 4x8 is going for the same price as the 2x4. I am totally stoked about this machine. While watching my first job, I couldn't stop grinning.

[@renelizares]

Patrick Hood-Daniel

[@harleyghost]

What a great idea, I never thought about a chain drive in this type of application. With the cost of large ball screws and any alignment issues this has my vote.

[@PatrickHoodDaniel]

The chain is a #40 with absolutely no bounce. A bit heavier than a bike chain; however, a bike chain would work just as well (I'm wondering if the lighter chain would bounce, like you say). The repeatability test that I have done is measured by putting a bunch of the same parts against each other with no visible deviation (I do mostly woodworking). I wouldn't be able to specify a tolerance range.

[@PatrickHoodDaniel]

You are correct. The resolution is quite a bit reduced. One benefit, however, is that I have noticed much reduced backlash, so I would bet that the accuracy is the same. Also, with microstepping, I can achieve 2800 or so steps per inch. My test cuts are better than when I had lead screws.

[@PatrickHoodDaniel]

Hey Walkifer, Thanks for the kudos. With the sprocket design, I have not tested deep cuts or materials other than wood. The great thing is that it would be very easy to design for NEMA 34 motors.

[@PatrickHoodDaniel]

The precision (repeatability) is great as long as the machine is controlled appropriately.

[@PatrickHoodDaniel]

@Defimov7 Chain drive is excellent. It is used in many precision machine in industry and is noted as such in books like "Mechanisms and Mechanical Devices". In my experience, so far (about 2 years so far with chain), it really is the best for eliminating the maximum amount of backlash in the cheap hobby realm due to the fact that the chain is tensioned. Another great form is timing belt.

[@PatrickHoodDaniel]

Yes, the resolution does go down, but you also have mocrostepping to increase the resolution. Precision and accuracy are different than resolution, and the chain is always in tension, so there is no backlash. The machine is only as good as the worst part of the machine. If the combined backlash from a lead screw is higher than, say, the resolution of the roller chain, then the roller chain would have better accuracy (commanded input matches the physical output) or precision (repeatability).

[@PatrickHoodDaniel]

The motor shafts have a flat, however, they are not important since I use a collar within the drive sprocket. The collar is a clamp style so it is fine for use with hardened steel shafts. I have not had any slippage so far. The idler sprocket is needed to reduce wear on the drive sprocket. I may design the next machine so that the chain covers half of the drive sprocket. With this machine, the wear will be minimal over a long period of time.

[@PatrickHoodDaniel]

I needed to use a collar the has an outside diameter that matches the inside diameter (bore) of the sprocket. This single effort took me about three months of research.

[@PatrickHoodDaniel]

@harleyghost Thanks. This is actually used in the industrial realm very often for this purpose. Ballscrews are great, but can also wear over time. The chain really does a good job with minimizing backlash.

[@PatrickHoodDaniel]

It's all in the microstepping. The new configuration in the version 4.0 uses smaller chain and a reduced pitch diameter, so the resolution is better.

[@schweinhund227]

Love that set up ... looks a lot cheaper than Screw ... its a Huge machine you have... Most Awesome ! Glad you shared this video with us ! all the best !

[@Walkifer]

Nevermind, I just self-answered my first two questions by looking at your other videos/comments. I still have this doubt about the idler-less design, though, I'll be very thankfull if you could guide me in the right direction.

[@PatrickHoodDaniel]

I am able to get grey precision at about .001 inch or .0254 mm.

[@Walkifer]

Are your motor's shafts completely round, or do they have a flat? I'm thinking on getting some sprockets from you, buy my motors' shafts don't have any flats. What stepdown/feedrate can you get without risking slippage (just to get an idea of what to expect when cutting MDF)? Could the machine be reliable without the idler sprocket, or would there be backlash (e.g. mounting the chain flat over wood, and just moving the sprocket over it)? Thanks!

[@Walkifer]

Great design! What's the torque of these motors, is it enough for deep cuts? Would it be enough for machining soft metals? Did you machine the sprocket, or just bought one that fits your motors' shaft? I'm waiting for my probotix 280/400oz-in kit to arrive (I'm in Chile), and using a chain system seems like a nice opcion considering it's really, really hard to get ACME leadscrews here (I've just used single threaded rod so far). Thanks :D

[@AdditiveAvery]

@anajonesr OMG i had to watch it over again. Yes that chain is very quiet! I must have heard it around 26 seconds and thought that noise was coming from the chain hahaha! Awesome job!! What do you mainly plan on machining?

[@Walkifer]

How did you fit the sprocket to the motor shaft? NEMA 34 would indeed be an amazing addition to your design; add a steel structure to that and you'll have a real monster!

[@PatrickHoodDaniel]

@TheLonetreecreations Since you are running a machine with roller chain, you should be able to get to a velocity comparable to the one in the video. You may not have the steps per inch correctly set according to the microstepping of the drivers. Let me know what your settings are for your drivers and steps per inch via email.

[@TheLonetreecreations]

Patrick, what kind of steppers and what kind of drivers are you running? Your table is really fast. Are you sure you didn't speed that video up? Mine won't even think about moving that fast. LoneTreeCreations

[@norby16]

If I only ran into you a year ago. In 2008 I partook on my own 4 x 8 cnc router project, which was put on hold, only to start meddling with it now again. Needless to say I'd much rather have enjoyed assembling something pre-designed and tested like this than going down the weary road alone. Looks like a great router, I'm in plastics business. Do you know how would your machine fair with acrylic and polycarbonate? 1/4 - 1/2 thicknesses? In the full kit, is table and router included? Thanks!

[@boss2master]

hello, great build, I like to build a CNC plasma for myself and I want to use a chain drive system on my CNC. please can you give me the number of the teeth on the stepper motor and the sprocket chain?

[@PatrickHoodDaniel]

The sprocket and roller chain I am using here is #40, but I use #25 on all of my machines.

[@PatrickHoodDaniel]

@brewerfan1993 Yes. If you use the correct control, you may not need coolant. I cut aluminum without coolant.

[@PatrickHoodDaniel]

@marshgre That build was a while ago. After all the parts were fabricated, it took around a day to assemble and test.

[@marvinpagaran8092]

what chain and sprocket are you using?

[@PatrickHoodDaniel]

This was a test back in 2009 where I used #40 roller chain and sprockets. I currently use #25.

[@jdjardine]

Great stuff. Can you do soft metals with this? It would be great to see videos of projects that you have completed with the blackToe as well.

[@Choice777]

awesome. so i guess this is good enough for non-industrial cnc machining, right ? no point in getting a ballscrew setup ?

[@lesterherreracastro4436]

Hi! Nice cnc. Friend, I have a question. what is the lead that you used en your roller chains? Or that you recommend me?. Thanks. :D

[@PatrickHoodDaniel]

@donkekeli Hi. Thanks for the interest in learning about CNC machines. We are setting up a training resource as a part of our forums at buildyourtools. Stay tuned to that forum. We should have some info on it in the few days.

[@PyroEvil]

425 oz-in stepper is strong enough for this size ( 4'x8' ) cnc? Which one did you use in this video? And what is the maxium ipm you can reach with this setup?

[@PatrickHoodDaniel]

@diyengineer By the way, after viewing the video again, the noise you are hearing is mostly coming from the motors. I may have had the drivers set to 1/4 microstepping which is not too quiet. The chain does have a slight sound, but the other noises around it is actually louder. Thanks for allowing me to reminisce. :))

[@PatrickHoodDaniel]

@diyengineer The #25 chain that I commonly use is extremely quiet. Anyway, the sound emitting from the router and machining is far more noisy and cacophonic. I definitely won't be using this machine in my bedroom anymore. :)

[@scott98390]

@Defimov7 Compared to most people that post comments on KZbin, your English is excellent.

[@PatrickHoodDaniel]

@TheEntertainer93 On the version 4.0 model, I use NEMA 24 425 oz-in motors for the y ans z axes and a NEMA 34 640 oz-in motor on the x-axis.

[@azeezulghaffar494]

Which stepper motor would be better for 5 * 8 feet CNC machine. Will Nema 23 4 amp 3.0 nm work. For wood work only.

[@JMSsturla]

Patrick Good day, I have a query, the x axis is accionas with two drivers or use a more current for the two pap engines. Thank you very much, and sorry for my English.

[@marshgre]

Nice work! How long did the build take?

[@b3bs]

good idea, but what about the resolution?

[@PedroMoralesRuerte]

Patrick parabéns pelo seu vídeo: por favor qual tipo de corrente e engrenagens que vc usou, quantos dentes e medidas dessas engrenagens desde de já agradeço.

[@Defimov7]

wow ) I want to use chain drive in my CNC. but I can`t find something about accuracy of this drive type. Is chain good enough for 3d wood routing? something like guitar carved body and neck? Sorry about my English

[@shelby50411]

Hi there..i have the chance to buy a used blackfoot 4x8 cnc with mach3 software in working cond for $1000 ....is that a good fair price?...i know tha deaign isnt very good nor rigid or accurate....but for the price and machining size ability should i jump,at $1000 or walk away from deal?

[@PatrickHoodDaniel]

Now I need to figure out a good project for acrylic and a pointed tool. Suggestions welcome. Thanks for the kudos.

[@gigicaly]

can you put up more videos demonstrating this kind of setup(with chain) please?

[@patricksreels]

Crazy rapids. Just curious how precise it is when cutting deep with high feeds. The steppers need alot of tourqe with this setup i guess. Regards

[@FlavioOliveira]

amigo, como ficou a precisão dela? tem alguma folga?

[@PatrickHoodDaniel]

A precisão foi muito boa. Consegui obter mais de 1000 passos / polegada. Como a corrente do rolo está tensionada, não há folga.

[@stanislasnguimatsa2555]

Hi Hi please how are your drivers set and how fast are the x and y axes

[@plasmaguy5]

Dude that is great stuff. Joe

[@leandrosilva6261]

Boa noite amigo que motor VC tá usando

[@stanislasnguimatsa2555]

Please it is the reference of the pinion you used I have the Nema 23

[@nikobr9]

Does current have accuracy?

[@blakenelsnelson]

how much backlash do you get using this type of drive system??

[@pheenix42]

You know, that's interesting....but, how do you eliminate position error in a chain? (I'm really ignorant here)

[@HEPGUNES]

How is the machine precision?

[@macmainuk]

what sisez of sprockets are they. on #25 chain the motor one looks small

[@AdditiveAvery]

That chain drive is LOUD. Why not go with a belt drive?

[@PatrickHoodDaniel]

Thanks!

[@QPatriot07]

Sounds like your Y-axis sprockets are out of alignment with the chain.

[@PatrickHoodDaniel]

In this video, I used #40 chain and sprockets.

[@Askjerry]

Sounds like ED209 from the original Robocop... grin.

[@PatrickHoodDaniel]

Grey was a typo. I meant to say great.

[@jaypeeblack5190]

Can-i use STP-58D106 for this size of cnc?

[@kavtech_midi]

wow..chain,,its look fast and strong...

[@theeelongated5]

That Sir, is The Bollox ! well in

[@ostry599]

nice speed :D

[@PatrickHoodDaniel]

Thanks!

[@acerkiwi]

That would make a good plasma cutter

[@PatrickHoodDaniel]

@antoine5612 Thanks

[@АндрейГрадобоев-ц3ь]

Скажите пожалуйста, какой шаг цепи используется?

[@Сергей-в8в2ш]

Андрей, пишите на английском. Они не ответят.

[@yazicib1]

I wonder what happened if chain is fixed to a rigid place (like carefully welded to a steel plate) so it wont be allowed to sag... would we have a better linear motion device? Instead of welding it can be tightened and clamped between two steel bars and supported from the bottom... would that work? Basically opposite of this: kzbin.info/www/bejne/rIGzmaqlmpeEg7c Where chain is used as rigid rack

[@eagleeye5520]

Can it work wth laser cutter ?

[@PatrickHoodDaniel]

Our greenBull does: www.buildyourcnc.com/Item/cnc-machine-greenBull-v4-4X-hybrid

[@eagleeye5520]

Patrick Hood-Daniel thanks i live in morroco and i know shipping is sooo expansive to my country for that i'm collecting infos to build mine and to be honest sir you helped me so much i salute you you're such a great man

[@ad221282]

After set up I will change all the wood pieces for others mad of aluminum!!!!

[@PatrickHoodDaniel]

@XXXTITEXXX Thanks

[@sZck]

Muito bom!

[@aceliter]

so cool !!

[@antoine5612]

Frikking Awesome!!!! I want that XD

[@Maxellz88]

отлично

[@Chrls5]

WOW!!!

[@akirahaschimoto]

cool,fast mashine.....

[@XXXTITEXXX]

wow

[@TheEntertainer93]

how strong are the cnc motors?