[diyengineer]

Grizzly called me today and confirmed that G0704 parts are going to be available on a confirmed date of December 3rd. He said no more, estimates its a for sure locked in date. (my order and some prices below, to change my random Mt3 taper grizzly over to R8, i got it at there tent sale, i don't believe they offer any MT3 parts FYI). Those are the prices though if anyone is interested, or just wondering how much they charge for stuff. Maybe more G0704's will come in with that shipment if anyone else wants to buy one?

1 P0704246 SPINDLE R8
EA 60.00
1 P0704246-1 DRAWBAR
EA 7.50
1 P0704246-2 RETAINER CUP
EA 3.00
1 P0704247 SPINDLE RING
EA 4.50
1 P0704249 QUILL SLEEVE
EA 54.00
1 P0704250 RUBBER RING
EA 1.25
1 P0704251 ADJUSTER NUT
EA 6.00
2 P0704252 ADJUSTER NUT SCREW
EA 1.25 2.50

[bill south]

Hoss;
An off topic question for you if I may!! I'm tooling up with the tormach type tool holders using your prints since there maybe a possibility of an ATC down the line! My question is, is there a reason for the .1" counter bore on the back of the tool holder body? I have a set of original tormachs and noted the originals have the same recess. But in my R8 holder, I can't figure out why a solid back wouldn't work just as well. Have you considered this?
I don't have a decent tool for cutting that recess so it's just a PITA.
What am I missing?
Thanks for all of the Hoss entertainment I've enjoyed for years!!!
Bill

[mrcodewiz]

I had the same question for Hoss a while back on the TTS holders. I don't recall his answer but I think it is to clear the R8 collet if it sticks out. That is the part that has been hanging me up (and breaking cutters). I think I will just recess the collet more and leave them flat if that will work.

On yet another unrelated note - has anyone completely trammed their G0704 in yet? I started doing mine this morning and I am sure I am doing it the wrong way but here are some observations:

I do not have a cylinder square so in order to determine how perpendicular the column was to the table, I mounted a DTI in the spindle and ran it up and down an angle plate mounted to the table.

1) The column was pretty good in the X plane - under .0005
2) The column was out .003 to .004 over 4" or so in the Y plane. To fix this, I shimmed a small amount between the column and base (behind the Y dovetails). This brought it to under .0005 over the same distance

Once I thought the column was perpendicular to the base, I wanted to tram the head so I used the same indicator on the spindle and swept the table. I first just concentrated on the reading at 3 o clock and 9 o clock to get the head into the right position. This is a pain unless I am doing it wrong because you have to first loosen the head's upper bolt (which will allow it to fall out from the column a little), then loosen the swivel bolt in order to move it, then re-tighten it and take your measurement.

Once the 3:00 and 9:00 read the same, I then looked at 12:00 and 6:00 which vary by a good .005". I really hate to shim the head since it swivels and it would be a pain to have to do that every time. Now I am wondering if either I did the column to base adjustment way wrong or it is now fixed but they initially squared the head in with an unaligned column.

any thoughts?

[angelballer]

Hoss;
An off topic question for you if I may!! I'm tooling up with the tormach type tool holders using your prints since there maybe a possibility of an ATC down the line! My question is, is there a reason for the .1" counter bore on the back of the tool holder body? I have a set of original tormachs and noted the originals have the same recess. But in my R8 holder, I can't figure out why a solid back wouldn't work just as well. Have you considered this?
I don't have a decent tool for cutting that recess so it's just a PITA.
What am I missing?
Thanks for all of the Hoss entertainment I've enjoyed for years!!!
Bill

Just thinking aloud and I may be completely wrong so take this for what it is worth... If you turn the tool holder to a shoulder, wouldn't there still be a slight radius depending on the turning insert used? This would cause repeatability issues as the mating surface is no longer flat. By adding the recess, you remove the edge with the radius meaning the mating surface is now completely flat.

[LeeWay]

Tormach sells an R8 collet that is flat on the end.
The recess isn't always needed on these, but needs to be there for other collets with a proud face. The extra clearance is good to have. To do this correctly, I had to mill my spindle face a bit to get the holders to seat properly. Not much material was removed, but once done, the TTS holders slipped in and out much easier. I had to check the tram, but was still close enough for me.
Mine is not a 704, but I suspect the same may need doing.

[photomankc]

I had the same issue with tram in the Y plane in my PM-25. I had to shim a bit to bring it in to about 0.002" over the width of the table. As I know I will almost never tilt the head I'll just have to live with it. When I go to CNC the Z axis I plan to drill holes for two more bolts to hold the head and that should allow me to pull out the last thousanth or so of nod in the mill's head, hopefully without the shims.

I did have to shim my column as well to get it back into tram after I tore it down to move to the basement. As for X tram:
http://www.cnczone.com/forums/769033-post14.html
Make these, there is really no way to describe how much easier it is to tram now. I made one for each side and now tramming in is a simple matter of loosening just slightly turning opposing set-screws and then retightning. Beats the hell out of pounding with rubber hammers. Also helps hold tram even through the occasional too-heavy cut or bump.

[mrcodewiz]

I saw that thread - I think I will make those tonight. How did you check the column? Did you use a cylinder square or another method?

[photomankc]

Couldn't obtain a good cylinder square so I ended up using the blade edge of a 8" china square to set it. I clamped it lightly in the vise and got the Y set with shims and then moved it to the X direction and tapped the column in. It's still not perfect, but I don't trust the square completely either. I don't seem to have much problem with hole locations between small and large bits though and that was all I wanted to avoid.

[rowbare]

Regarding the undercut on the TTS flanges see section 1.2 Principles of Operation: http://www.tormach.com/document_libr...TTS_Manual.pdf

bob

[bill south]

Thanks Guys for the TTC information. I was not aware that Tormach had two different R-8 adapters. My model is the flat faced model so it didn't make sense to have a recess. I'm going to order a spare and if the new adapter has a rounded face, I'll end up buying a grooving boring bar and doing the work.
Thanks again.
Bill

[wmacky]

So, do the G0704's come with inspection reports like some of the other BF20's come with?

Hoss, do your z gibbs look any better that some that have come with the BF20's?

[hoss2006]

So, do the G0704's come with inspection reports like some of the other BF20's come with?

Hoss, do your z gibbs look any better that some that have come with the BF20's?

Either I didn't get an inspection report or I missed it, I got one of the first G0704's, maybe they forgot, I don't remember seeing one.
I yanked it apart immediately so it didn't matter.
The gib strip is machined on 3 sides and scraped on one side, nice and flat.
Hoss

[mwood3]

Either I didn't get an inspection report or I missed it, I got one of the first G0704's, maybe they forgot, I don't remember seeing one.
I yanked it apart immediately so it didn't matter.
The gib strip is machined on 3 sides and scraped on one side, nice and flat.
Hoss

i didnt get an inspection report either...

my gibs look very nice also, the Z gib looks like someone bit it off to length rather than cut it...but it works good...nice and smooth

[Wmacky1]

Thanks guys, That's good news. Even if I were to get a bad one, it sounds like a probable good replacement gibb would be possible.

I'm getting nervous about the whole freight thing. Never had a "freight" shipment before! I'll need to request a short notice day off work, and I hope I can get lift gate delivery. My current vehicle is a Jeep!

[diyengineer]

So, do the G0704's come with inspection reports like some of the other BF20's come with?

Hoss, do your z gibbs look any better that some that have come with the BF20's?

Both of mine came with full inspection reports and someone actually wrote out all the specs of accuracy in each test. I can snap a pic if you want, its kinda nice cause it basically tells me how the heck to verify all these measurements with pictures haha. <----nooob

[mrcodewiz]

Would anyone mind making a video of how they adjust the Z gib? No matter how I do it, it just doesn't feel right. And even when it seems tight (or even too tight), tightening the lock will cause the head to deflect.

[photomankc]

Would anyone mind making a video of how they adjust the Z gib? No matter how I do it, it just doesn't feel right. And even when it seems tight (or even too tight), tightening the lock will cause the head to deflect.

Welcome to my world on the PM25. If I don't lock it then surface finish suffers, if I do then the tool deflects about 0.002" to the side give or take. I have to tram the thing to the locked condition and know that it's out of tram and out of position when unlocked. All tightening it down does for me is change which lever causes the head to shift. I have a new gib strip ordered. I want to see how they compare to each other but I may just make my own down the road to see if I can shape it to fit better. When I turn the top lock I can see the gib actually flex a bit so I think it just doesn't fit well. When I take the head off again I plan to double check for any grit or debris but I'm pretty sure that this is just a bad fitting gib, or more ominously a poorly cut recess for it.

[mrcodewiz]

Aren't the gibs scraped in for the specific machine or is the scraping on them purely cosmetic?

[photomankc]

One would hope they were custom but I'm not sure I would expect it to have been done that well if at all for these Chinese machines. We'll see when my replacement gets here in Nov.

[kanton]

At some point in the future I might purchase a G0704 and CNC it. At present I have a Taig Mill with a Deepgroove1 Gecko G540 control box which I would like to use in the conversion. I know that I would have to get a larger power supply for it but I am would like to know the best available stepper combination to use with the G540.

On this page G0704 Electronics Hoss suggests:

"Bare Minimum Recommendation - This runs at 50 Volts but only 3.5 Amps
Should be easier for newbies to setup but is definitely weaker. Don't expect
to be able to hog as much metal with this setup.**

(1) Geckodrive G540 4 Axis driver - $249 (with other purchase)
(2) KL23H2100-35-4B 381 oz-in stepper motor (X and Y axis) $49 / $98
(1) KL23H2100-30-4BM 495 oz-in stepper motor (Z axis) / $59.95 *
(1) KL-600-48 48V/12.5A power Supply / $129.95

Total = $536.90

* Run with a 1.33:1 pulley ratio (24 and 32 tooth pulleys) for 658 oz/in output."

But on Keling's page Page Title one of the packages is:

"G540 3 axis package (one G540 + one KL34H295-43-8B, 906 oz-in +
Two KL23H2100-35-4B (1/4” Dual shaft with a flat) 381 oz-in + one
KL-600-48 48V/12.5A 115V /230V
power supply): $581.95"

It would seem that the Keling package would not require the 1.33:1 pulley ratio that Hoss suggests. In fact it would allow a Z axis stepper larger than the 570 oz-in stepper Hoss uses now. I realize that this probably not the optimum combination but it would speed up the Z axis.

Bottom line question, is there a better stepper combination for the G0704 using the Geckodrive G540 4 Axis driver that would perform better than Hoss's Bare Minimum Recommendation?