Information On G0728/9

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Rick H

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Hi All: I am in Springfield, MO on a three week work assignment. While I was here I wanted to stop in at the Grizzly Store and look at the smaller Grizzly milling machines that I want to use for home hobby projects. Let me say that I have little experience working with milling machines but I think I can have fun with one and perhaps accomplish making some useful projects.

I went into the Grizzly store today to look at the mill that I was most interested in, the G0759. Unfortunately, they did not have one in the store and per the salesman I spoke with they don't expect any until September or October....Rats! While I was looking at a G0704, which is the G0759 less the DRO, I spied a G0728 which is a benchtop style knee mill. I walked over to it and gave it the once over and I can say I really liked this machine. The mechanical controls felt very nice compared to some other machines. Another customer told me the reason they felt smoother was due to the fact the ways are given more attention when the machine was put together. True it is about $1,000.00 more than the G0759 and it doesn't have a DRO, but it seemed like a well made machine.

So here is my question to the group: does anyone here own or use a G0728/9 Grizzly mill and if so do you like it? Also, how does one tram the mill in the "Y" axis? It looks like it's pretty straightforward to tram the "X" axis, but I couldn't figure out the "Y".

Thanks for any help and information.....

Rick H.
 
OK, I guess I can assume by 30 views and no replies that no one owns or may have used a Grizzly G0728/9 mill on this forum. Be that the case, has anyone heard anything good or bad about this mill? How about adjusting the Y-axis tram?

Thanks in advance.....Rick
 
No personal experience here other than to say I looked quite hard at these when I was searching for a milling machine. I liked the knee style better than the square column/movable head style but for most other aspects I preferred the RF45-clone style machines.

The 6x26 style of mill/drills have quite a following and for most home machining jobs the table and travel is adequate.

That said, I ended up going with a 2/3 style full featured BP head machine as I really wanted a knee mill and more Y-axis travel.

Sorry I couldn't be of more help. With as many of this size machine are being used I am really surprised no one has chimed in with some personal experience/input.

Mike.
 
Thanks for the reply Mike. By saying you went with the 2/3 style BP head what machine are you referring to?

Rick
 
I purchased the PM935TV from Matt @ Quality Machine Tools in PA.

Here is a link.
http://machinetoolonline.com/PM-935HighPrecisionMills.html

It is a Taiwanese Bridgeport style mill. Things I liked about it are that it was made in Taiwan, smaller footprint than full-size Bridgeport yet has a 3hp motor, full-featured Bridgeport head including tilt and nod functions, also has three speed power downfeed. It is similar in size to the Jet 836 model but one thing I have not seen in any mill this size is the Y-axis travel, it is 12" where as the others are around 9-9.5" is all. Only one like this in a smaller physical size that I was looking for.

Check it out. I should have mine any time and I will be doing a full review once it is in the shop and set up. At that time I should be able to provide some better feedback.

Mike.
 
Rick, I had a G0704 and traded up to the same mill Mike has. To answer your tram question, on the G0704 you need to shim the column (a bit of a PITA.) On the G0728 style you can't really adjust for Y tram unless you somehow shim the column where the head mounts. Maybe you won't need to for what you are building or because it's okay as is. No way to know until you get your machine, I suppose. I had great service from Grizzly when the rpm display died on my G0704, but it was difficult to buy a replacement nylon gear that shears easily and is often out of stock. I'd buy from them again.

When I decided to move up, I was going to get the larger 8x30 Taiwan-made version (G0730), but figured for the extra money the Bridgeport style head was a better deal. Unfortunately, since you either don't know what you want to make or simply haven't mentioned it, it's hard to suggest which mill is best for you. Maybe you're like me and need to actually use something (like a mill) for awhile before you figure it out.

One possible option is to buy a smaller and cheaper machine like the G0704 and use it for a year or two to see what you do with it. If you want to step up in size later, there are tons of guys who want them for CNC conversions and you probably won't lose more than a third of your purchase price if the machine is in good condition. That's essentially what I did, and I don't regret having taken that path. Good luck!

-Ryan
 
Thank you all for your responses, you have given me food for thought. I will just be using this for small home and model projects and some firearm work where I really need precise drilling ability.

Rick
 
Just a little follow up to my original question about tram adjustment on a G0728, G0729, G0730, G0731 and G0678. I called Grizzly Tech Services and asked how one goes about adjusting the Y-axis on these mills. The gentleman I spoke with, Frank?, was very helpful. He told me the Y-axis can be adjusted, but it's a bit of a job. There are "doors" on the back side of the columns that can be removed and access gained to bolts that hold the baseplate to the column. Once you know how far out the Y-axis is you can loosen the bolts and shim between the column and baseplate to adjust tram. I looked at several of these mills here in Springfield, MO at the Grizzly store and it certainly looks like this can be done on these mills. Unfortunately, there is a filler of some sort placed around the outside of the column, perhaps for cosmetic reasons, that would have to be split in order to allow the column to move freely. I feel much better now about purchasing one of these mills. Thanks to all for your help.

Rick
 
Not to resurrect a long dead thread, but I thought I would give some long term results on my Grizzly G0729 milling machine. I have had it for over four years now and have done quite a few of small odd jobs on it. I added a DRO PROS 4 axis digital readout system and that was that one outstanding thing that I did. The digital readout made my life so much easier. Aside from the DRO, the mill has been a constant love/hate relationship. There are three things that crop up with this mill over and over again. First is adjusting the Y-axis tram. It is a major pain to accomplish this task without help from someone. After multiple attempts at this process I finally have it set at about .001" to .002"out. If I try for better than that I go over, so it is where it is. I think being a little bit off affects surface finish, but it is what it is. Some may recall that I asked Grizzly before I bought this machine about adjusting the Y-axis tram and they first told me it was easily done by splitting the column and the base and shimming it. That bit of information wasn't quite right and when I called them back to tell them their idea didn't work they had no clue on how to tram the darn thing.

The second item of anguish is the Z-axis adjustment mechanism. It is about as rudimentary an adjustment system as one could possibly make and install on a milling machine. A rope and pulley setup would work better. When I first received the machine you could literally feel every tooth in the gear set especially when raising the table. Going down with the knee was an experience in terror too because the table would drop a bit and stop and then drop a bit and stop. I also figured out that the table would move around going up and down. It's better today than four years ago, but it is still aggravating.

Last but not least is the table itself. I probably made a mistake thinking a small table would be in my best interest, but that smallness hurts table stability. If you forget and put a little too much weight on one side of the table or the other the tram goes right out the window. More than once I have been doing something and leaned on one side of the table, or the other, a little too hard and next thing I find out is the part I am working on just went south with the tram and yes the gibs are properly adjusted. I have yet to put the belt cover back on the machine which I took off a long time ago. I found out the hard way that if you inadvertently dropped the cover when closing the thing it could impact the X-axis tram. So off went the cover and the problem. Just have to remember to keep your hands out of the belt area when the machine is running.

So that's about it for the long term report. More than once I have wanted to send this machine to a scrap yard, but just kept tinkering with it and usually somehow or other the current problem gets rectified or almost so. I admit it, I am more of a perfectionist today than I was four years ago and I envy those that have a good working, proper functioning knee mill. My main purpose when I bought this mill was for dead accurate multiple hole drilling and tapping on X-axis items. If I only used the machine for that purpose it would be okay especially with the DRO, but only okay. I have learned through experience that the fine downfeed for the quill is worthless and the only way to maintain decent accuracy of drilling depth is to use the course quill feed handle while keeping some tension on the quill lock, but not enough to truly impede movement. I have tried the knee in the past for this, but the herky-jerky knee adjustment doesn't bode well for accuracy.

If I had it to do over I would never have purchased this machine. It has left a bad taste in my mouth for anything but drilling and tapping holes. Maintaining accuracy during any sort of milling operation is nothing but a crap shoot and there is little fun in the process. The worst part is knowing at the start of a project that everything is set with the machine, only to get halfway through the job and something moves or changes and you have to start the job all over again. For anything more than drilling I simply must check tram beforehand or face complete exasperation. Yes, I know what I bought when I purchased this machine, but hope springs eternal. I could see a PM 835 in my life if I wasn't so darn old. Just thinking about hauling the Grizzly out of the basement and bringing a new machine in makes me want to take a nap.

Happy Trails...….
Rick H.
 
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