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tonygagey
08-07-2014, 08:15 AM
Hi , I am thinking about keeping the cost down on my rockcliff styled ganntry build by using 2 nema 17 for the y axis and 1 fof the z and a 23 for the x, whats the general thinking on this, I will be using a boch 500 router and will be cuting upto 18 mm ply.
And I will be using Chinese moters and electrics from ebay, any thoughts on those please.

irving2008
08-07-2014, 10:47 AM
Don't see how you can use 2 motors on Y as Y is across the gantry. Also Nema 17 are generally lightweight, good for 3D printers but will struggle to pull a heavy router around through ply unless you're just tickling the surface. Anyway the cost savings will be negligible once you throw them all away and do it right... How big is this machine?

Neale
08-07-2014, 11:08 AM
I think that the OP is using the American XY convention, rather than the European. Do Americans stand in a different position when they use these machines? Just idle speculation!

irving2008
08-07-2014, 12:23 PM
Southport UK, 6 posts in 6 years, started the rockcliffe in 2009 then tried to sell it partially built in 2010, has asked about Chinese drivers before in 2010 as well... no point in reiterating the answer, it hasn't changed. Tony, try using the search function, the Chinese question has been done to death. And if your Rockcliffe is using threaded rod a pair of cheap Nema17s aren't going to move it fast enough to cut anything harder than butter...

JAZZCNC
08-07-2014, 02:48 PM
My input ends with the words "Rockcliffe".!! . . . Only good for burning and then still under performs.:hysterical:

tonygagey
09-07-2014, 10:03 PM
Southport UK, 6 posts in 6 years, started the rockcliffe in 2009 then tried to sell it partially built in 2010, has asked about Chinese drivers before in 2010 as well... no point in reiterating the answer, it hasn't changed. Tony, try using the search function, the Chinese question has been done to death. And if your Rockcliffe is using threaded rod a pair of cheap Nema17s aren't going to move it fast enough to cut anything harder than butter...
6 posts in six years? Tried to sell it partially built? What relevant's does this have to my question about using 2 nema 17 on a 4 axis machine ? I sold my first 3 axis carcass true , but had forgotten I had alredy asked about Chinese moters , please note 4 axis as I understand it = 2 moters on the y (?) Axis I thought 2 17 moters in sync would be =to the job , obviously not but still your answer was the only one anywhere near to my question.
So thanks!

Lee Roberts
09-07-2014, 10:25 PM
6 posts in six years? Tried to sell it partially built? What relevant's does this have to my question about using 2 nema 17 on a 4 axis machine ? I sold my first 3 axis carcass true , but had forgotten I had alredy asked about Chinese moters , please note 4 axis as I understand it = 2 moters on the y (?) Axis I thought 2 17 moters in sync would be =to the job , obviously not but still your answer was the only one anywhere near to my question.
So thanks!
I did wonder the same myself Tony and understood it to mean dual motor, single axis, I'm quite familiar with the Rockcliffe machines as I built a model A A few years ago now. Sorry about the response you received from others.

Have a search on the forum if your thinking about the TB driver system as there is two threads I know of that talk about this board, if it's another board let us know which and we may be able to advise, get yourself nema23 motors the 3Nm version, they cost more I know but they will serve you well and allow you to make use of them in the future if you do decide to build something new and quite a bit more substantial, their pretty much the "go too" motor for these machines.

.Me

tonygagey
08-08-2014, 09:00 PM
Well bullit bit! Ordered system 4 from roy at diycnc. Just waiting for him to post when power supply in.
Also going to build new carcase using Dave Gatton's Sidewinder plans. To ensure accuracy I am having the plans made as a pattern laser cut in 2mm steel. Expensive but I think it will be worth it !

Lee Roberts
08-08-2014, 10:48 PM
Cool look forward to seeing the results, keep us updated!

tonygagey
12-08-2014, 08:49 PM
Got motors etc from roy today, anyone know were I can get nema 23 mounts from that wont take 6 weeks or cost a small fortune !

EddyCurrent
12-08-2014, 10:29 PM
anyone know were I can get nema 23 mounts from that wont take 6 weeks or cost a small fortune !

Are you planning to use belt drive or a direct coupling design ?

tonygagey
13-08-2014, 03:21 AM
Direct drive

JAZZCNC
13-08-2014, 09:36 AM
To ensure accuracy I am having the plans made as a pattern laser cut in 2mm steel. Expensive but I think it will be worth it !

WHAT.!! . . . Are you for real.! Your going to waste money laser cutting steel templates to build a machine made from PAPER.!!

For the price of the laser cutting/templates you could buy all the steel needed to build the frame and have 50X stronger machine. Bolt it together if you cant weld or have someone weld it for you.

Also can I just say you are going about this all wrong regards the electronics. Roy's stuff is ok but it's more suited to smaller machines like Mills not routers. This is because the drives are low voltage with a Max of 40Vdc I believe. Routers run much higher feed rates than mills so we need more speed from the motors and steppers get there speed from volts. 40V max drives will be restrictive to a router machine unless you use a high pitch ball or lead screw and this will lower resolution so your getting a unbalanced machine.

Trying to cut costs on electronics is asking for trouble and never ends well.!!

EddyCurrent
13-08-2014, 10:30 AM
Got motors etc from roy today, anyone know were I can get nema 23 mounts from that wont take 6 weeks or cost a small fortune !

http://www.cnc4you.co.uk/index.php?route=product/product&path=78&product_id=445

Or you could make one from a piece of box section.

tonygagey
13-08-2014, 11:28 AM
Forgive my ignorance as I am new to cnc ,well , that is ithas taken me 6 years toget tothe pointwere I have bough nearly all the stuff I need.
And I was unaware that geting a steel carcase made up to order was going to cost me less than 145 , which is what it is costing me to get the cad files laser cut and laminating them to the 18mm birch ply.
But I am already committed to the system 4 set as that was here yesterday, and quite frankly was more than I could really afford, so I'm stuck with that, besides the machime won't be cuting anything harder than 18mm ply and mostly foam and wax patterns for castings in resin , aluminium, brass and hopefully in time bronze!

tonygagey
13-08-2014, 11:31 AM
To be honest with myself I'm building the bloody machine to prove I can.

phill05
13-08-2014, 12:33 PM
Are you for real.!

Also can I just say you are going about this all wrong regards the electronics. Roy's stuff is ok but it's more suited to smaller machines like Mills not routers. This is because the drives are low voltage with a Max of 40Vdc I believe. Routers run much higher feed rates than mills so we need more speed from the motors and steppers get there speed from volts. 40V max drives will be restrictive to a router machine unless you use a high pitch ball or lead screw and this will lower resolution so your getting a unbalanced machine.

Trying to cut costs on electronics is asking for trouble and never ends well.!!

It's not all about speed!!! From many years experience working Roy's 40Vdc drives I am on 1405 screws round supported rails, I profile 12 to 20mm aluminum with DOC of 2 to 3mm with great success also 2.5D relief's in aluminum & stone with DOC up to 4mm so I don't understand how you come to say "you would have an unbalanced machine" just not so there is no problem with Roy's drives.
For what the OP wants System 4 is a great system to use.

usual disclaimer only a very satisfied user.

Phill