# CNC Conversion Grizzly G0704 V.S.  G0759



## angelfj1 (Mar 17, 2014)

Well, I finally decided on the B20 size mill.  I will place an order this week to take advantage of the Grizzly 10 percent off sale.  The plan would be to purchase a manual mill, either the 0704 or 0759, and machine the conversion parts per Hoss Machine Phase II.  Based on the photos, manuals and parts lists, the G0759 is identical to the G0704 with the exception of added DRO and DRO scales.  The difference in price is $500, but I was hoping that the DRO would help me do a more accurate job of milling the CNC conversion parts.  Is this a valid assumption?  After I convert to CNC, and begin to use Mach3, I suppose the DRO would become redundant?  However, I may be able to sell the DRO and scales to a manual G0704 owner at an attractive price.  I could not find any details regarding the DRO on the 0759 mill. I phoned Grizzly tech support.  The 0759 mills will not be available until late May at the earliest.  The tech could not confirm that the DRO is one of their standard models such as the H6091 ($832.).  If you look at the online photo of the 0759 mill, there are a few close-up photos showing the DRO.  One photo shows a DRO just like the H6091 but the other photos show something totally different.  I would not be surprised if the Chinese engineered a cost reduced DRO for this new machine to keep the price lower.  The one photo showing a H6091 type DRO may have been for the prototype photo only.  

So, I can either order a G704 mill alone or with the H6091 DRO or order a G0759 mill and wait a couple of months ( and hope that a new desighn DRO has reasonable performance).  decisions, decisions


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## Ray C (Mar 17, 2014)

DRO is always a good thing and yes, it will help make parts faster.  Accuracy and precision is your job though...

It will be hard (if not next to impossible) to install DRO scales as well as home and limit location switches on a CNC machine.  DRO is largely redundant when you have CNC and you'll be chasing your tail when you see one reads slightly different from the other.  CNC machines know position by relative coordinates and expected location based on signals sent to the motors.  DRO reads by dead reconing via sensors.  The two will not likely agree consistently.

Also, as part of your conversion, you'll need to convert to ball screws.  My CAM software will do small amounts of hill climbs for stock removal even when the job is setup to do primarily conventional cuts.  To get away with hill climbs, you're better off with ball screws.  Try that with ACME screws and you'll be in for a surprise.

As far as looking closely at advertisement photos to identify components, I would not put much faith in what you see.  In almost all cases with all vendors, the accessory items could be different than what's shown in the photos.  It's largely impossible to keep the advertisement photos up to date with the actual shipped product.


Ray


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## dave2176 (Mar 17, 2014)

Get the G0704, build simple mounts to get cnc running and then build super cool cnc controlled mounts.

Dave


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## SEK_22Hornet (Mar 17, 2014)

Since you are going CNC, another option would be to buy the G0704 and get a couple of the Igaging DRO's from Davidh.  You'll be out less than $100 that way. It already has a digital readout on the Z axis (quill only), so you only need to add the X and Y. I bought a 6" and a 24" from David and am getting ready to install them now that warmer weather is coming.  I have seen people use epoxy and VHB double sided tape to install them (search this forum for Igaging or DRO mounting), so you should be able to do a quick temporary install pretty easily. Order an extra gear or two for the G0704 drive - it is part number P0707209 and it is $10. You may never need it, but some of us have, and it is out of stock a lot (has taken 3 months to get sometimes). It is the gear that strips if you push the mill too hard.


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## angelfj1 (Mar 18, 2014)

SEK_22Hornet said:


> Since you are going CNC, another option would be to buy the G0704 and get a couple of the Igaging DRO's from Davidh.



I just got off the phone with Grizzly tech support.  As I am about to order a G0704 mill, I asked about the iGaging DRO's, and specifically which ones to order for a G0704.  This guy said he didn't know.  Of course I was surprised by this answer.  I went to the iGaging site and could not find any application info for their DRO's either, just the model listings. 

These are the four DRO's listed:

35-706-P:  0-6” DigiMag Digital Scale and Magnetic Remote Readout 
 35-712-P:  0-12” DigiMag Digital Scale and Magnetic Remote Readout 
 35-724-P:  0-24” DigiMag Digital Scale and Magnetic Remote Readout
35-736-P:  0-36”     DigiMag Digital Scale and Magnetic Remote Readout

So, can someone tell me which of these to order for my G0704 x and y axis?

Thanks,

Frank


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## angelfj1 (Mar 18, 2014)

ok ignore this


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## bloomingtonmike (Mar 19, 2014)

You can cut the igaging scales so just order the size longer than your travel.

Look up Yuri's DRO project - igaging scale wireless DRO project for a bluetoothed android tablet and an arduino. Readout as large as your screen and scales powered by arduio's powersupply - no more battery issues and little readouts.


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## SEK_22Hornet (Mar 20, 2014)

angelfj1 said:


> I just got off the phone with Grizzly tech support.  As I am about to order a G0704 mill, I asked about the iGaging DRO's, and specifically which ones to order for a G0704.  This guy said he didn't know.  Of course I was surprised by this answer.  I went to the iGaging site and could not find any application info for their DRO's either, just the model listings.
> 
> These are the four DRO's listed:
> 
> ...



I bought the 0-6" and the 0-24" to put on my G0704. I don't have them installed yet, but hope to get started on that in a week or so. Based on a recent post by Davidh, the scales are about 2" longer than the range, so the 0-24 is about 26" long.


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## kd4gij (Mar 20, 2014)

If you my the G0759 I would by the dro when you go CNC at an atractive price.


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## angelfj1 (Mar 21, 2014)

kd4gij said:


> If you my the G0759 I would by the dro when you go CNC at an atractive price.



OK  I'll keep that in mind.

Frank


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