Timig belt driven router?

Machine design, rails, bearings, screws, nuts, couplings, ...

Timig belt driven router?

Postby Abcdeflijus » 18 May 2013, 00:49

Hello everyone!

Looks like time has pushed me to build another cnc machine, as I am no longer happy with my old one. 800mm/min maximum reliable feed rate and dremel 4000 with its high revolutions is not the best combination for the bits life and time saving to make parts. So I am planing to build a desktop router of about 3020 working area. The first fing I want to do is to change dremel in to other more profesional and more suitable spindle for the job. My choise is settled down on this one from aliexpress: http://www.aliexpress.com/item/NEW-the- ... 54059.html
If anyone already has this one, would be greate to hear some feed back. Anyway, if not, that what do you think, is a 500W a sufficient power? Need to mention that mostly I am goint to mill plywood and other softer woods.
Aluminium is olso in my dreams, but this depends on how strong the machine I will make.
Another problem wich is faceing me, is drive unit. I have nema 17 Stepper Motor - 58 oz.in (400 steps per rev) driven with Big Easy drivers. Not the most powerfull kit, but it can do some job. I was thinking about changeing the driving unit to timing belt, as it can increase the speeds of the machine, while keeping steppers revolutions lower and getting more torgue from it. A good similar example would be ZenBot Mini cnc router, wich is also driven by nema 17 motors and timing belts.
What I want you to ask, is what king of timing belts and pulleys I should use, to get the best result from the motors, and is there any formula to calculate what maximum feed rate I can expect from this combination? If anyone has some experience with timing belts, would be great to hear something about that.
Thank you for your replys!
Abcdeflijus
 
Posts: 13
Joined: 11 Dec 2012, 12:00
Controller: Mk2/4

Re: Timig belt driven router?

Postby Abcdeflijus » 01 Nov 2013, 11:41

Hello once again!

Since no one was interested in my post and there were no replys, I will make it by my self :)
It took some time for me to build a new router, the one that I was planing to build.
But before I'll share it with you, lets give some respect to my old one, wich has done the most part of the job.
I was surprised, that it can even cut aluminium. So here it is!
Old cnc.jpg
Old cnc.jpg (220.75 KiB) Viewed 5112 times


As you can see in my previous post, that its maximum reliable speed was only 800mm/min, what was not enouth for me. I wanted something faster and not so expensive for the moment, so I choosed belt drive.
And I can say, that I did get a results few times better than I was expecting. With my new machine I can get rapid speeds up to 20000 mm/min. Unfortunately I hadn't made any test cuts for the moment, but I think I will be happy with the speeds I will get from machine. Here's how it looks.

New cnc.jpg
New cnc.jpg (200.88 KiB) Viewed 5112 times


The setup up is: Nema17 stepper motors 58 oz/in (400 steps), GT2 timing belt (6mm width), GT2 timing puleys (16 tooth), big easy drivers, power suply (27 volts) and for shure planet cnc controler Mk2/4.
Cutting tool as you can see is dremel 4000. I think for this machine now it is more suitable and will do the job for some time. I the future I think about changeing it in to some other.
Now I think it will take me some time to learn this machine, setup it correctly and for the best performence.
If some one olso has a belt driven router and has any experience, I would enjoy if that experience would be shared ;)
Abcdeflijus
 
Posts: 13
Joined: 11 Dec 2012, 12:00
Controller: Mk2/4

Re: Timig belt driven router?

Postby Andrej » 01 Nov 2013, 16:34

It is not that I'm not interested. I just don't have experience with such machines.
Andrej
 
Posts: 2489
Joined: 10 Jan 2012, 16:09
Controller: Many controllers

Re: Timig belt driven router?

Postby Abcdeflijus » 01 Nov 2013, 17:59

Andrej, it's ok, I am not blaming anyone ;) If no one has belt driven machine, than I will be sharing my experience. And what I have discovered in a few days while learning to run it, that one belt on X axis is not enougth or it should be placed somewhere in the middle of the gantry. Right side of the gantry (without belt) is swinging a little bit. I the future I am planning to change the construction, that both sides will have belt drives. Allso I think, that 6 mm width GT2 belt is a little bit too narow for the cnc, so double belts would make axes more rigid.
Abcdeflijus
 
Posts: 13
Joined: 11 Dec 2012, 12:00
Controller: Mk2/4

Re: Timig belt driven router?

Postby Moonglow » 26 Nov 2013, 17:47

can you publish some vids ? thanx :)
Moonglow
 
Posts: 104
Joined: 11 Jan 2012, 04:45
Controller: Many controllers

Re: Timig belt driven router?

Postby Abcdeflijus » 08 Dec 2013, 09:52

Shure, I am glad that somebody is interesting in my creation :D
Here is a test video of helix sample file from cnc controler software. Feed rate is 6000mm/min, so far not the limit for idle run. http://youtu.be/ELR1p6UrN5g
And here is the video of a real cut. Just a small shape for a test cut. Feed rate is 3000mm/min. Also not the top speed, I have tried to cut much more faster, but then I need to find better settings for the machine.
http://youtu.be/8EETGRrKJKQ
Anyway for the moment 3000 is more than enougth for me to get faster cuts and quate good accuracy.
By the way, about the accuracy. I am considering to buy a dial indicator to find out how accurate is may machine. There are plenty off them in store, but I was woundering if the depth gauge like this https://www.varle.lt/static/uploads/products/39/ska/skaitmeninis-gylio-indikatorius-0-25mm.jpeg could do the same trick?
Thank you Moonglow for being interested in my post, I will upload more videos in the future.
Abcdeflijus
 
Posts: 13
Joined: 11 Dec 2012, 12:00
Controller: Mk2/4

Re: Timig belt driven router?

Postby Andrej » 08 Dec 2013, 18:56

Nice videos. I hope you'll publish more.

I recommend you get classic analog dial gauge. Analog has several advantages over digital and it is easier to use.
Something like this:
http://ecatalog.mitutoyo.com/Dial-Indic ... C1215.aspx
Andrej
 
Posts: 2489
Joined: 10 Jan 2012, 16:09
Controller: Many controllers

Re: Timig belt driven router?

Postby Abcdeflijus » 08 Dec 2013, 19:52

Thank you Andrej. I also think that mechanical gage is more reliable than electronic, so I have already written to santa, that I want to get one for this cristmas :D I have changed the design of machine a little bit, now the belt on my Y axis (my Y is on supported rails) is on both sides, so the Y axis is more stable now. And I have a dust skirt now, becouse I became tirred of holding the vacuum cleaner hose close to the spindle :D I will share new videos soon on these days. By the way about videos. Is it possible to upload video directly to the forum? I have tried, but didn't succseed. If yes, than wich format?
Abcdeflijus
 
Posts: 13
Joined: 11 Dec 2012, 12:00
Controller: Mk2/4

Re: Timig belt driven router?

Postby Andrej » 09 Dec 2013, 07:44

You can not upload videos directly. Use Youtube.
Andrej
 
Posts: 2489
Joined: 10 Jan 2012, 16:09
Controller: Many controllers

Re: Timig belt driven router?

Postby Abcdeflijus » 12 Dec 2013, 12:37

So, for those who are following my topic, I am glad to share more material.
New video of updated machine with belts on both Y sides, and dust skirt.
http://youtu.be/QejAcBLI-Uw
Wood is black alder, wich I found very friendly for cutting and getting quite good finishing.
Here are some photos:
Elija.jpg
Elija.jpg (183.49 KiB) Viewed 4823 times

You can see that finishing is not perfect, I gues it's becouse of cheap chineese bits, but baybe something else ;) It is also after some sanding.
Here is another one, wich was damaged, becouse of too big depth cut.
Elija damaged.jpg
Elija damaged.jpg (96.21 KiB) Viewed 4823 times

Some more shapes for my one year old daughter ;)
Elephant.jpg
Elephant.jpg (230.15 KiB) Viewed 4823 times

It has already been in her mouth, so it's no longer a brand new look ;)
And the last one wich is made from asp. The difference between these two materials are clearly seen.
E.jpg
E.jpg (148.24 KiB) Viewed 4823 times

I liked black alder much more, as it was more easy to cut, the finished surface is better and it is approved by baby's cnc toy's quality inspector :D
Inspector.jpg
Inspector.jpg (96.86 KiB) Viewed 4823 times
Abcdeflijus
 
Posts: 13
Joined: 11 Dec 2012, 12:00
Controller: Mk2/4

Re: Timig belt driven router?

Postby Andrej » 13 Dec 2013, 10:40

You have beautiful toy's quality inspector. How old is she?
My workshop apprentice is 2.5 years old.
Andrej
 
Posts: 2489
Joined: 10 Jan 2012, 16:09
Controller: Many controllers

Re: Timig belt driven router?

Postby Abcdeflijus » 13 Dec 2013, 10:52

She is almost one year old. Her birthday is on 3rd of January. Any suggestions what could be made for a birthday with cnc? :D
Abcdeflijus
 
Posts: 13
Joined: 11 Dec 2012, 12:00
Controller: Mk2/4


Return to Mechanics



Who is online

Users browsing this forum: No registered users and 1 guest