[Engineer123]

I just want to ask in your personal experiences which benchtop milling machine is the best? I have been looking differents machine but they all seem the same.
Grizzly G0704, *Lathemaster LMT25L, Seig x3 milling machine, etc.

How can I know the difference between these machines and which one is the best for the price?

[lcvette]

I can only speak to the G0704, but I am very satisfied with the product and Grizzly's support, I would imagine that they all are very similar in their production for this range machine, I made my choice based on price and was lucky to have Grizzly deliver within 4 days of placing my order, others have had long wait times so this may be a big determining factor if the mills are not available for immediate shipment.

Chris

[hive8]

So far very happy with my G0704 as well... i think for the money you have a hard time to beat it. I also was very lucky and got it delivered 4days after placing my order.

[hoss2006]

Best at what?
What's best for your needs may not be best for mine.
However, I made a chart a while back comparing 5 popular machines and their most prominent advertised specs.
Many other machines could be added with many more specs though.
Hoss

[FannBlade]

Best at what?
What's best for your needs may not be best for mine.
However, I made a chart a while back comparing 5 popular machines and their most prominent advertised specs.
Many other machines could be added with many more specs though.
Hoss

any thoughts on this one? Vertical-Mill/G0678

[109jb]

any thoughts on this one? Vertical-Mill/G0678

That looks like an OK machine, but since it is a knee mill, I personally would go for a used bridgeport or other quality brand machine. A decent one coul be had for about 1/2 the price of that Grizzly mill.

Some of the pros and cons I see with that mill compared to a bridgeport are:
Pro - VFD controlled motor
Con - Smaller table than a bridgeport
Con - Ram does not extend like a bridgeport does
Con - It doesn't appear that the head tilt has a worm drive to assist in tilting/raising the head and tramming.

You expressed an interest in CNC, and having worked as a machinist on manual and CNC mills, I have the following observations. A knee mill can definitely be made into a CNC machine and I have worked on several that were. One that I worked with was X and Y axis only with manual positioning of the Z. Several were X,Y, Z with the Z axis being movement of the quill. One that I worked on had a goofy setup with X,Y,Z1,Z2 where Z1 was quill, and Z2 was the knee.

The X-Y only would be easy to do, but it is a bit of a pain to work with just X-Y.

The XYZ with quill feed works very well, but you are limited in Z travel a bit. On those machines I found myself haveing to raise and lower the knee sometimes to change tools, or get clearance, or similar. Worked pretty well though and since raising the knee is accurate and you don't lose XY position it wasn't that bad.

The machine that had X-Y-Z1-Z2 worked reallly well, but we never used Z1. All the guys that used that machine quickly found out that it was much easier to just program all of the Z moves into moving the knee. It worked really well.

The thing you have to consider strongly on converting a knee mill is what system you will need (servo or stepper), and what that means to cost and setting it up. They can be converted and make very nice capable CNC machines. Depends on what you want out of it.

Having said that, consider that a true VMC does not have a knee. They work by having a bunch of head travel. This is exactly how a square column mill drill works. Sure they have a quill too, but when CNC'd the quill is generally not used, so esentially you are mimicking the way a VMC works. They also work pretty darn well for a manual mill to if that is how you want to start out. The square column mill drills come in a variety of sizes from table top model that one guy can carry easily up to almost 1000 pound monsters. All of the mill in this range have been converted to CNC at one time or another.

If I were going to buy a mill right now for my own personal use, with the experiences I have had, I would buy a square column mill drill. Depending on what you want to do with it would determine the size you would go for.

It sounds like you may not have much machining experience, so might I suggest that you try the lower end of the scale instead of sinking $10K into something you may not need. You can get a mini square column mill like this one:

G8689 Mini Milling Machine

Then CNC it and have a whole lot less money into it than buying something that may be great but overkill for what you actually want to do. These can be made into pretty good little CNC hobby mills as has been shown many times by many people. Are they suited to mass production of large parts? no, but they can get you a lot of experience with machining and CNC.

Just like you don't need a sledgehammer to drive a finish nail, you don't need a CNC mill with a huge table if you want to make small parts.

My opinion (Worth what you paid for it)

[FannBlade]

Good point on the travel.
Also looking at this one G0720R
The one you listed is way to small. I'm converting a 3n1 now and looks like i'm going to dump the mill head and just use the lathe so need a suitable replacement.

The large part I need it for is 24x9x1 6061 with about 70% material removal.

Spent all day yesterday on the Tormach site and also think the 770 will suit me needs very well and is designed to be disassemble to move were the 1100 isn't. But will also cost 5 times the grizzly and I still need budget for the CRP4848 that I will use to do the finish cuts.
Converting doesn't bother me but sure is hard without a mill to cut parts.

[109jb]

OK. Knowing the size of the biggest part you want to do helps. That size part, if you want to do it all in one setup will need a pretty large machine. You are looking at the RF-45 size machine, but not all of them are created equal. The table size and travels differ from machine to machine. The G0720R lists table travel of 9-5/8 x 16-1/8 on the table. Not enough for the 24 x 9" size of your part. You can usually get a little more travel than the specs say by modifying slightly, but I don't think you will get 8" more on X on that one. You could fixture to do the part in 2 stages, or get a bigger machine. International hobbies sells a much improved dovetail mill that has 12" x 30" table travel. Not sure about price as they no longer have an online store, but they also offer a CNC version of their mill that uses closed loop feedback servo control. Might be an option. Here is their link.

IH CNC Mills & Machinery - Made in the USA

Another RF-45 clone that I have been looking at because of price is the Penn Tools top tech mill. At $1695 (May 2012) it is about the lowest cost RF-45 I have seen. It has 20 x 9 travel and by modifying and using a little overtravel I think you may be able to get the 24+ inch X travel you are looking for. You would also need to get a little more Y travel, but its already at 9" so shouldn't take much. I was able to get about an extra 1-1/2 inches on my little RF-25 clone. It may take a little doing though, so don't take that part to the bank so to speak. Here is a link. Top Tech Geared Head Mill/Drill Dovetail Column - Swivel Head 90° << Metal Working Machinery << Online Catalog << Penn Tool Co.

For the size part you are looking at, a used 9x49 Bridgeport would have the table travel you need. This might not be a bad option. If the part is only 1" thick, a Z axis quill could probably do what you want with manual positioning of the knee if necessary. A power feed on the knee makes this part not too bad of a compromise. If you decide to CNC the knee for the Z axis, I think a servo would be best unless you are willing to live with some slower Z-axis feed rates.

CNC knee mills are also easy to find on the used market. Might want to consider this route. Here is one ebay right now. Used machinery dealers will also have CNC knee mills.

Tree Journeyman 320 3-Axis 2HP CNC Milling Machine | eBay



Not knowing all of the particulars of your part (how many, how often, tolerances, etc.), it is hard to say, but doing the part in 2 separate setups may be a good compromise too.

One thing to consider with a part that large is holding tolerances. The motors and control software have good precision but the mechanics of the machine come into play. At the lengths you are talking about, you would be best with ground zero-backlash ballscrews $$$$ and then would still need to map the screws. If your tolerances are at all tight, you may just be best off with a real CNC machine with box ways, proven track record, etc. The Tormach may be a good choice in that regard.

[Mad Welder]

I just want to ask in your personal experiences which benchtop milling machine is the best?

Hi there Engineer123, welcome.... and it really boils down to what do you require your machine to do, and if you can be more specific as to your future machining requirements...well then someone here would be more specific in their recomendations for you too, otherwise you'll get multiple machine suggestions and each suggestion in it's self would be valid for each of us who suggested it because it suited our needs......

hope this hasn't confused you more either, but that chart Hoss suggested in post 4 below, I also looked at it before I made my decision......

[underthetire]

Went through this with my father recently. Found a lot of these mills didn't have tapered gibs, a nice feature to have. He placed an order from grizzly for the $3800 dollar one, they kept sending him emails saying its a new machine, shipment delayed for months. He then found a pm full size knee mill on eBay brand new. It was slightly shorter table than a Bridgeport, didn't have the Bridgeport mounting eye on the back of the ram so it fit better in the garage. Came with single phase vfd, DROs,a vice and collets and I think a clamp set. Was about 4200 delivered. Look around.

[FannBlade]

Defiantly going to look around. I would really like to just find the iron and build from there. I have a wholesale tool down the street think I will go see if they have a junk pile.
Saw some good prices on VMC's today on ebay in the $6000-$8000 range.
I hate to buy a new machine then replace everything with more new parts.

Sorry about hijacking this thread hope the OP doesn't mind.

[yooooda]

You may want to look at the Machine Tools Warehouse MD001. It is a clone of the IH mill. Square column, 12" X 30" travel (Y,X) and a good 20" plus of Z travel. It's heavy, nearly 1000 lbs and has a slightly wider spindle speed range.
On the down side, expect to do some tweaking to get things straight and square over the entire range.

[SCzEngrgGroup]

That looks like an OK machine, but since it is a knee mill, I personally would go for a used bridgeport or other quality brand machine. A decent one coul be had for about 1/2 the price of that Grizzly mill.

Some of the pros and cons I see with that mill compared to a bridgeport are:
Pro - VFD controlled motor
Con - Smaller table than a bridgeport
Con - Ram does not extend like a bridgeport does
Con - It doesn't appear that the head tilt has a worm drive to assist in tilting/raising the head and tramming.

You expressed an interest in CNC, and having worked as a machinist on manual and CNC mills, I have the following observations. A knee mill can definitely be made into a CNC machine and I have worked on several that were. One that I worked with was X and Y axis only with manual positioning of the Z. Several were X,Y, Z with the Z axis being movement of the quill. One that I worked on had a goofy setup with X,Y,Z1,Z2 where Z1 was quill, and Z2 was the knee.

The X-Y only would be easy to do, but it is a bit of a pain to work with just X-Y.

The XYZ with quill feed works very well, but you are limited in Z travel a bit. On those machines I found myself haveing to raise and lower the knee sometimes to change tools, or get clearance, or similar. Worked pretty well though and since raising the knee is accurate and you don't lose XY position it wasn't that bad.

The machine that had X-Y-Z1-Z2 worked reallly well, but we never used Z1. All the guys that used that machine quickly found out that it was much easier to just program all of the Z moves into moving the knee. It worked really well.

The thing you have to consider strongly on converting a knee mill is what system you will need (servo or stepper), and what that means to cost and setting it up. They can be converted and make very nice capable CNC machines. Depends on what you want out of it.

Having said that, consider that a true VMC does not have a knee. They work by having a bunch of head travel. This is exactly how a square column mill drill works. Sure they have a quill too, but when CNC'd the quill is generally not used, so esentially you are mimicking the way a VMC works. They also work pretty darn well for a manual mill to if that is how you want to start out. The square column mill drills come in a variety of sizes from table top model that one guy can carry easily up to almost 1000 pound monsters. All of the mill in this range have been converted to CNC at one time or another.

If I were going to buy a mill right now for my own personal use, with the experiences I have had, I would buy a square column mill drill. Depending on what you want to do with it would determine the size you would go for.

It sounds like you may not have much machining experience, so might I suggest that you try the lower end of the scale instead of sinking $10K into something you may not need. You can get a mini square column mill like this one:

G8689 Mini Milling Machine

Then CNC it and have a whole lot less money into it than buying something that may be great but overkill for what you actually want to do. These can be made into pretty good little CNC hobby mills as has been shown many times by many people. Are they suited to mass production of large parts? no, but they can get you a lot of experience with machining and CNC.

Just like you don't need a sledgehammer to drive a finish nail, you don't need a CNC mill with a huge table if you want to make small parts.

My opinion (Worth what you paid for it)

A knee mill with X, Y, quill and knee CNC'd can work quite nicely. You use the knee only to apply tool length compensation, and you then have full quill travel to work with on all tools. I've operated mine that way for years, and it works great.

But, if I had it to do all over again, I would not buy a knee mill to CNC....

Regards,
Ray L.

[Engineer123]

What do you think of this machine?
MILL DRILL ( e.g. RF-31, JET, BIRMINGHAM MACHINERY ) | eBay

[awerby]

Those round-column machines are difficult to use, because they lose position when you raise or lower the bed. And any machine with a drill-press type quill will be difficult to convert to CNC; you'd need to replace it with an entirely different mechanism. Keep looking...

Andrew Werby
ComputerSculpture.com &mdash; Home Page for Discount Hardware & Software

[109jb]

What do you think of this machine?
MILL DRILL ( e.g. RF-31, JET, BIRMINGHAM MACHINERY ) | eBay

The round column mills can work just fine if the parts that you are machining are flat plat type parts, but if you are buying a new machine then there really isn't a reason to go with the round column machine. This video shows what you can do with a round column mill if you take it to an extreme. As mentioned, the round column would lose position though if the head has to be raised. Also, the RF-31 you posted about only has 18-1/2" x 6-1/4" table travel. A G0704 can be made to have more than that. You had said your part was 24" x 9".

[Engineer123]

109jb, awerby

What kind of machine do you recommend instead of a round mill considering the price range ?

[FannBlade]

Look at something like this
G0704
It has a big following here

[109jb]

109jb, awerby

What kind of machine do you recommend instead of a round mill considering the price range ?

Sorry. I am getting confused. You started the thread, but another person was asking questions too and I am getting confused about which question came from which person.

In any case. I have been doing a bunch of reviewing of different conversions, different mills, etc. As I mentioned, I currently have a Harbor Freight round column mill that I am converting to CNC. I personally want to get a mill that has a dovetail column because of the problem of losing X-Y position when raising the head. I would love to get a RF-45 clone and then convert it to CNC. However, I am starting to come to terms with what I need vs. what I want. I basically need more table travel, which the RF-45 clone would give, but I can live with a lighter duty machine and take lighter cuts. So, I actually placed an order for a Grizzly G0704 just yesterday. I will be using my round column mill to make the parts for the G0704, and then I will sell the round column mill. The benefits of the G0704 machine as I see it are as follows.

1. Value - $1200 delivered anywhere in the USA and it includes the cabinet stand. From the research I have done, I believe this is a great value and is from a reputable company. I have bought other items, including machines, from Grizzly and they are pretty darn good in my book when it comes to customer service. They stock all the parts you would need and have a 1 year warranty. Some of the other importers likely don't stock parts for their machines and you would need to wait for them to get them from overseas. That alone is worth something. I said before I have a Harbor Freight round column mill and on that one I decided to take the chance. I haven't had any problems, but if I do I think I would be pretty much on my own.

2. Easy to CNC - Many followers, plans, kits etc. Hoss, a user on here has a great link and tons of information on converting to CNC, vidoes of the capabilities. His stuff is an excellent resource for this machine and what it is capable of. He offers conversion plans too.

3. Lower cost to CNC - The RF-45 would require larger motors, larger power supplies, etc. This makes the cost of converting the RF-45 clone higher than the G0704 which can very successfully use NEMA 23 motors, lower cost switching power supplies, and motor drivers.

4. Machine travels - The G0704 already has 18+ inches of x travel which is enough for me, and the Y-travel has been shown to be able to be increased to about 9". I personally have decided that this is sufficient for my purposes. Obviousy the RF-45 has this much travel to begin with, and in the same way, the travels for that machine could probably be increased some too, but I seldom need more than about 7 inches of travel. On my present round column machine, I have about 6" of travel and this has sometimes posed a problem for me as I sometimes use 6" wide stock. This is a personal choice that you will have to decide if the travel is sufficient for your purposes.

5. Variable speed motor - The variable speed motor that comes stock on the G0704 is a nice feature. I plan to eventually have the motor on mine interfaced with my CPu so that spindle on/off, speed and direction can be controlled via the machine controller software. I am using EMC2 on mine. Eventually, I will probably have a 3 phase motor with VFD on it, but that could be years down the road. The stock motor will serve well enough for now.

6. Mobile - The G0704 is a relatively light machine which makes it much easier to move around and even for some people to get in their basements. Usually, more weight is a plus in machines like this because it generally means more rigidity. However, more weight than is needed is just more weight. Looking at video's about the G0704, it seems to me that the machine is rigid enough to do a quality job if you don't get crazy with speeds and feeds. So, it is rigid enough for my purposes. The RF-45 clones are about 2-1/2 times heavier. I plan to put mine on a mobile base. I have an extra Shop Fox mobile base that I bought for a table saw I wound up selling. This will work out good for me for my shop situation.

Those are the main considerations I used before I ordered. Also, I managed to sell a few items in the last few weeks to get the money to purchase a G0704 with enough left over to start the CNC conversion. This enabled me to keep my round column mill for making parts for the G0704. If I had gone the RF-45 route, I would still not have enough money to buy the RF-45 clone mill all by itself. It was a tradeoff, but I think I'll be happy with the decision. I decided that I would rather build the best G0704 I can rather than a RF-45 clone with corners cut for cost reasons.

Hope this helps.

In the end, you will have to decide for yourself what fits your needs because none of us know all those needs.