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View Full Version : NEW MEMBER: Hello from Ireland..........Need info....



aquila787
10-09-2012, 05:27 PM
Hello

I'm new to cnc. I bought Geoff Williams book a while back and am now about to build my first cnc router. Wondering if the plans in the Williams book are out of date re; electronics etc.

I will be using the router to machine violin fronts and backs and maybe necks as well, propeller blades too.

I also want to be able to machine aluminium HTD pulleys and am wondering could I do it on the cnc machine described in the Williams book and if not would I need to install a fourth axis....and if so where to go for information.

Anyone got the g-code for propellers/violins/htd pulleys or where to find it?

I know thats a big order but thanks in advance if you can help.

John

JAZZCNC
10-09-2012, 08:03 PM
Never heard of him or the book.! What's it called.?

Can you give us some details, things like Size, construction material and the electrics he's suggested. A picture would really help.

To be honest the Electrics are easy really and depending on a few factors like Budget and machine size then the choice can be narrowed down to a small selection of modern equipment.

Regards the pulleys then to do them properly a CNC router really ain't the best tool for the job.?
The problem comes from a few factors but mainly boils down to the spindle and machine strength.! To make good pulleys you'll want a form tool and that will need slow spindle speeds which most router type machines don't have and it's quite hard and very expensive to find a spindle that can do both high speed for routing and slow speeds for milling.
Then the machine needs to be very tall to allow the 4th axis, which you will need, to fit and give clearance for tool etc. This compromises the machine strength making the Z axis need to have a very long extension for when it's a router cutting thinner material. A long Z axis flex's giving poor finish quality.

Really the two don't fit together nice unless designed very strong with a lot of adjust ability built into them. A machine built to be an all round machine will never be the best at anything and there will always be a compromise.

If most of your work is Wood then I'd build a router just for that purpose where it will excel then buy a Milling machine with 4th axis for the gear hobbing etc if really needed.? Or just buy the HTD pulleys ready made has most of the time unless specials or very large it's there not worth time and effort making them.!!

Give more info on this Willy bloke with possibly a pic or link and will gladly have a look.!

irving2008
10-09-2012, 08:44 PM
Jazz... this is the book, from 2003: http://www.amazon.co.uk/CNC-Robotics-Build-Your-Workshop/dp/0071418288/ref=sr_1_1?ie=UTF8&qid=1347302375&sr=8-1

I didnt realise there were so many books on the subject:

The CNC Cookbook: Amazon.co.uk: Edward J Hess: Books (http://www.amazon.co.uk/The-CNC-Cookbook-Edward-Hess/dp/0982110308/ref=sr_1_4?ie=UTF8&qid=1347302375&sr=8-4)

Build Your Own CNC Machine (Technology in Action): Amazon.co.uk: James Floyd Kelly, Patrick Hood-Daniel: Books (http://www.amazon.co.uk/Build-Your-Machine-Technology-Action/dp/1430224894/ref=sr_1_5?ie=UTF8&qid=1347302375&sr=8-5)

Building the KRMx01 CNC: The Illustrated Guide to Building a High Precision CNC Router: Amazon.co.uk: Mr Michael Simpson: Books (http://www.amazon.co.uk/Building-KRMx01-CNC-Illustrated-Precision/dp/1938687108/ref=sr_1_6?ie=UTF8&qid=1347302375&sr=8-6) (I like the title of this one!)

CNC Machining Handbook: Building, Programming, and Implementation: Amazon.co.uk: Alan Overby: Books (http://www.amazon.co.uk/CNC-Machining-Handbook-Programming-Implementation/dp/0071623019/ref=sr_1_1?ie=UTF8&qid=1347302569&sr=8-1)

The Kiwi Bloke: Easy Home CNC eBook: Paul Oliver: Amazon.co.uk: Kindle Store (http://www.amazon.co.uk/The-Kiwi-Bloke-Easy-ebook/dp/B0074YV4KA/ref=sr_1_9?ie=UTF8&qid=1347302569&sr=8-9) (kindle only)

http://www.amazon.co.uk/CNC-Handbook-Hans-B-Kief/dp/0071799486/ref=sr_1_29?ie=UTF8&qid=1347302631&sr=8-29 This one due out Dec 2012

JAZZCNC
10-09-2012, 09:29 PM
Jazz... this is the book, from 2003: http://www.amazon.co.uk/CNC-Robotics-Build-Your-Workshop/dp/0071418288/ref=sr_1_1?ie=UTF8&qid=1347302375&sr=8-1


Errrrr . . . If that pic on the front is anything to go by then I'd say only use it for propping the door open.!! Very Dodgy looking machine and even dodgier looking wiring. . lol

After seeing that book then I'd say have a look around the forum and then start a "build thread".?? Yes "Build thread" even thou you haven't started building or even have a design yet.

The best Build threads (and often machines) to me are not just the ones showing the pics of the machine but the ones where it's took from a seed of an idea to the finished article.
Start by giving details of your ultimate wants, desired materials to cut and machine size required and all the info to build one will soon follow. The design and best style to suit your requirements will soon follow that and before you know it the build will under-way.?

irving2008
10-09-2012, 10:49 PM
Errrrr . . . If that pic on the front is anything to go by then I'd say only use it for propping the door open.!! Very Dodgy looking machine and even dodgier looking wiring. . lol
...

I thought this 'review' was telling: "There is one specific useful area for the newcomer. 53 pages of the 307 pages in the book are given over to a reproduction of a data sheet for an SCS-Thompson L297 motor controller chip." Although why an out of date and largely outmoded controller chip needs to take up 1/6 of a book on CNC I fail to understand. Anyway, who builds controllers these days? It certainly isn't any cheaper than buying them.

Seriously Aquila, if you want to build something as a starter machine pre-designed from a set of plans (and from the reviews it seems the book is lacking in that area) have a look at the Rockcliff machine: DIY CNC Router Plans (http://www.rockcliffcnc.com/Pages/CNCRouterPlans.aspx)

However, as Jazz says, you'll get more capability for your money and something bespoke to your own needs, if you work through your own design with input from the guys on the forum.

aquila787
10-09-2012, 10:57 PM
Thanks guys. I might have jumped the gun a bit as I ordered some of the electronics at the weekend.. I've since seen complete controllers for reasonable price. Anyway I plan to log it all with plenty of photos etc. I'll come back here for advice when I need it.

Thanks again.

John

JAZZCNC
10-09-2012, 11:09 PM
Thanks guys. I might have jumped the gun a bit as I ordered some of the electronics at the weekend.. I've since seen complete controllers for reasonable price. Anyway I plan to log it all with plenty of photos etc. I'll come back here for advice when I need it.

Thanks again.

John

John honestly what you have done is "THE" most common mistake folks make in CNC and just about everybody has done it, me included.

Best advice I always give is BUY NOTHING untill you have the design settled upon, esp the electrics.
Electrics are the last thing you need and seen has most builds are done over many months not weeks then all your doing is wasting warranty and potential for technology to change and price drops in the parts you've already bought.
This technology change/price drops is happening now with the introduction of Digital drives and they are starting to drive the price of analogue drives down already so in another 6-12mths time they could be half the price you'd pay now and you'll probably buy digital drives for the same money has analogue drives are now.?

Plus what you think you need now will be completely different to what you actually need.??

Seriously start with a design then only after you fully understand whats needed then start buying.!