Re: [CAD_CAM_EDM_DRO] Re: How to convert a Grizzly 1006 Mill to CNC

on 2007-10-18 18:43:58 UTC

Perolalars,

Many thanks in advance for your information. Yes this project can easily jump in price based upon the options selected. I have since writing this post have been in contact with Roland Friestad of Cardinal Engineering whom gave me some valuable insight as you did too! The same questions were asked of him and basically I can go as elaborate as the pocket allows. I think I am on the right road, I have the electronics side and software and computer side completed and I am down to the mechanical aspects of the project.

I settled on using 425-600 oz motors and have designed a couple of drawings already using motor mounts. I am in the process of inputting all of specifications into the drawing such alignment and orientation of parts that are to be used in a autocad. Then finally, I will then be moving into machining the parts etc. The last piece of the puzzle for me is deciding on ball screws or precision screws. Heck I am not making things for the aerospace industry so I can live with a little slop. I just need to machine a few parts and then repeat the process numerous times over. Eventually and as time and money allows maybe the more accurate option can be addressed. Again thank you for your information, it is greatly appreciated.

Todd
----- Original Message ----
From: perolalars <per.petersson@...>
To: CAD_CAM_EDM_DRO@yahoogroups.com
Sent: Thursday, October 18, 2007 11:46:25 AM
Subject: [CAD_CAM_EDM_DRO] Re: How to convert a Grizzly 1006 Mill to CNC

--- In CAD_CAM_EDM_ DRO@yahoogroups. com, hannu <hvenermo@.. .> wrote:

>

> Your mill (all typical medium milling machines) is about 0.02 mm

+/- in

> absolute precision, 0.01 mm +/- in resolution unless its damaged.

You

> probably have about 2-3 x that in backlash.

>

> Expensive ? this depends.

> You should use offset mounts and timing belts and pulleys for

various

> reasons - if you need better your price range and needs are 10x

higher,

> and you would know it. They are the easiest, best cheapest way

unless

> you want sub 0.01 mm precision, at which point your costs and

> difficulties are 10x higher. They will help with mid-band

resonance,

> set-up, and hunting. They are the best option, unless you need a

very

> very stiff set-up. If you do, you will need tighter nuts, and many

many

> other things, some of which are expensive. I don´t recommend it. Do

the

> cnc with belts first, when you get experience you can always change

it

> if you want, the belts were cheap. The only thing wrong with belts,

is

> if you are looking for less than 0.01 mm backlash and accuracy, in

which

> case you will want hard mounts.

>

> At that point, you would also like set-up jigs, you need to change

the

> bearings and bearing mounts in both ends, make a new, stiffer yoke

(3x

> more mass), preload the bearings, go to bigger motors and direct

drive,

> probably servos, probably ball-screws, error-map the screws, about

3000

> - 4000 $ in parts. This quality bearings will be 100-200 each,

mounts

> are 400 $ if bought, so 1600 for 4 etc. etc. And you still might

use

> belts, just bigger and tighter and more accurate.

>

> Whats expensive for you ?

> Your cheapest best solution is nema23 hi-quality motors 425 ozin

(2 for

> 110$), 2:1 belts (6$ belts, 50$ pulleys), 24 v psu (surplus),

> non-isolated basic breakout board (12$), surplus pc (free), mach3

trial

> (free), kit drivers about 2 amps 24 volts (30$ each, 60$) change

nothing

> else.

> About 1 week to fab motor mounts etc, use surplus flexible ethernet

for

> cabling.

> It will work, quite well, for 240 $. Not expensive, imho.

>

> You can use it to do work as good as the machine is capable of, 10x

> faster than manual, with excellent repeatability.

>

> If you want a recommendation for whats the best choice, how much to

you

> want to spend, ballpark ? If you can possibly afford it, isolated

bob

> (120), gecko 201s drivers (180) and you are good to go. Total 360

$.

> Still not expensive.

> If you want a very good choice, 48 psu (100), gecko 203v drivers

(260),

> newer pc (2.5 ghz plus, 300), total mach3 w. wizards (230), total

1060.

> This would be for "real " production use, easy and very reliable.

>

> If you need specific reasons, ask, but you can take it as a given

that

> the cheapest solution is already really good and will work. When I

> started, 5 years ago, there were, and still are, people saying they

> build everything for under 100 $. Just let them say it, and ignore

the

> fact that a decent chuck (m2 precision) is 40$, and decent endmill

3 mm

> 10$ with collet etc...

>

> The one thing most people don´t do, is turn the motors around, and

then

> put them under the axes to save space, which costs nothing extra

and

> works better and they are less in the way. I recommend it, if

possible.

>

> FWIW - Today I built a cnc rotary table as a lathe (mill?)

accessory

> (heavy 12 kg, 6", strong, about 120) with kit driver (30), sonceboz

> swiss modern motor (20$) for 190 $. I will now go hook it up and

hope

> for no smoke ...

>

> > Hello,

> >

> > I spent the better part of 2 hours looking for a kit or HOWTO on

this

> > subject and I found out that it is very expensive, not an easy

> > project and or simply very little information about it.

> >

> > I am looking information of others that have done this conversion

> > with this machine or like machines/clones etc. Let me also say

that I

> > can make all the motor mounts, motor coupling etc and I have

motors

> > and a controller and some software products to drive it.

> >

> > I recall a mod that was done that simply coupled the motors in

place

> > of the cranks and others use offset mounts with drive belts. Pros

and

> > cons would good information to have too.

> >

> > I dunno for sure how accurate the mill is in a manual process is

in

> > the first place, so that is a concern going that route. I

personally

> > do small projects like motor mounts, transmission mounts etc for

> > motorcycles. However I would like to perform pocketing too for

things

> > like right angle gear boxes etc. So eventually I would think

ground

> > precision screws are in order. I am no expert at this so I wanted

to

> > drop a few lines to the experts.

> >

> > Many thanks in advance.

> >

> > Todd

Hi hannu

Sorry for a newbie breaking in but what is "48 psu" and where can i

find it and what does a breakout board do and where can I find those?

Hope I am not posting wrong here but picking up knowledge where ever

I can find it for my own build.

regards

perolalars







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