[scarr]

Hi all,

I am about to purchase a benchtop mill and before I did I wanted a little feedback on my choice.

http://www.cncmasters.com/cncbaron.html

I will have to have it imported as I live in UK and after working out total cost it will work out at about £6700 (GBP)

Please feel free to coment and even suggest anything better for price.

I intend to prototype, make molds and do one off special work in Aluminumum, plastic and mild steel. I might even attempt making PCB's with it. I like this mill because it looks easy to get up and running quickly, I'm more of a "do it on CAD and then just let the machine get on with it" person.

Thanks

[Cube3]

This looks pretty much exactly the same machine I have just bought from Warco UK. I have bought a manual Machine, GH Universal. There are quite a few of these machines around branded under different names. It seems quite a good machine with just a few drawbacks, the spindle speed is too slow for carbide cutters so HSS only and the Z axis has quite a heavy gearbox and motor to deal with. If you order this machine, let me know how you get on, be very interested how a CNC'nd version works out. Simon

[scarr]

OK after posting I searched the forum for the Baron and found people saying that the "Personal CNC 1100" and "SmithyCNC" are better, I thought I had found what I wanted now I'm confused again

Anyway please comment and I'll try to understand / take onboard what your saying, wouldn't it be just great if 30 people posted a reply saying "get XXX machine its the best" then I could simply buy it with confidence, but I suppose life is not that easy

Thanks on advance.

[philbur]

5" z-axis travel on the quill, 1600 rpm spindle with 60hz is going to be proportionally lower on 50hz and for mold making and work in alumiium it's going tbe a real pain. It doesn't appear to have a complete set of way covers or a one shot oiler. Also I can't find details of max feeds or rapids.

Well here's vote 1 of 30. Buy a Tormach PCNC1100, I shipped one to Norway and love it. Check the Tormach forum on here and on Yahoo, plus the Tormach web site.

IH is another possibility but more expensive if you want "out of the box up and running". I don't have any experience with this machine but many users seem to be very happy with it.

Regards
Phil

Hi all,

I am about to purchase a benchtop mill and before I did I wanted a little feedback on my choice.

http://www.cncmasters.com/cncbaron.html

I will have to have it imported as I live in UK and after working out total cost it will work out at about £6700 (GBP)

Please feel free to coment and even suggest anything better for price.

I intend to prototype, make molds and do one off special work in Aluminumum, plastic and mild steel. I might even attempt making PCB's with it. I like this mill because it looks easy to get up and running quickly, I'm more of a "do it on CAD and then just let the machine get on with it" person.

Thanks

[SCzEngrgGroup]

What on earth is the logic behind making a small mill with only a 2000RPM spindle? So many of these small machines have such limited spindle speed they'd be nearly useless! A little machine like this should have a 6-10K RPM spindle.

Regards,
Ray L.

[philbur]

It's because the base machine is a manual mill/drill with a gearbox.

I think this will be the next big change since the introduction of the square column. Surely a VFD and belt drive can't cost that much more to make than a gearbox. Then your speed limit is only dictated by the price you are prepared to pay for the spindle. I quess machines like the X4 are already moving in that direction, I think the rest will soon follow.

Phil

What on earth is the logic behind making a small mill with only a 2000RPM spindle? So many of these small machines have such limited spindle speed they'd be nearly useless! A little machine like this should have a 6-10K RPM spindle.

Regards,
Ray L.

[ataxy]

yep i think to, you can allready see IH is offering there mill with an optional vfd motor

[MichaelHenry]

I think this will be the next big change since the introduction of the square column. Surely a VFD and belt drive can't cost that much more to make than a gearbox.

Looks like they already have a VFD option - $750, I think.

In addition to the spindle speed and Z travel limitations you mentioned, the claimed accuracy of 0.003" in 12" doesn't sound so hot either.

Mike

[philbur]

Hi Mike and ataxy,

My point is that the gearbox should be dumped and replaced with a VFD and a couple of pulleys. The gearbox costs $$$, consumes hp stirring oil and limits the max rpm. Most RF45’s are limited to 2,000 rpm or less. The IH does very well to get to 3,600 rpm but that’s it. The only advantage of the gearbox over a VFD is that it gives you massive low-end torque, which is great on a heavy-duty horizontal mill with outboard spindle support. On a low-mass vertical mill it's a mismatch, you can't use the low end grunt due to lack of rigidity. Machines with relatively low rigidity perform best with small diameter cutters running at high rpm. This argument applies even more to very low-mass machines, like an X2 for example.

Just some personal thoughts, not trying to upset anybody, but interested to here other reasoned opinions.

Phil

Looks like they already have a VFD option - $750, I think.

In addition to the spindle speed and Z travel limitations you mentioned, the claimed accuracy of 0.003" in 12" doesn't sound so hot either.

Mike

[ataxy]

Hi Mike and ataxy,

My point is that the gearbox should be dumped and replaced with a VFD and a couple of pulleys. The gearbox costs $$$, consumes hp stirring oil and limits the max rpm. Most RF45’s are limited to 2,000 rpm or less. The IH does very well to get to 3,600 rpm but that’s it. The only advantage of the gearbox over a VFD is that it gives you massive low-end torque, which is great on a heavy-duty horizontal mill with outboard spindle support. On a low-mass vertical mill it's a mismatch, you can't use the low end grunt due to lack of rigidity. Machines with relatively low rigidity perform best with small diameter cutters running at high rpm. This argument applies even more to very low-mass machines, like an X2 for example.

Just some personal thoughts, not trying to upset anybody, but interested to here other reasoned opinions.

Phil

i totally agree with you
edit: by the way that 5'' of travel is a bit ridiculous in my point of view

[philbur]

Agreed but the 5" limit depends on the class of work you intend to do. For me the big issue with using the quill for Z is lack of rigidity when extended plus how do you adjust slack when it wears, or more probably when it arrives new with slack already in it. The sloppy rack and pinion drive doesn't really lend itself to precise CNC control either.

Phil

edit: by the way that 5'' of travel is a bit ridiculous in my point of view

[SCzEngrgGroup]

"by the way that 5'' of travel is a bit ridiculous in my point of view" - You do realize even a Bridgeport has only 5" of quill travel? Seems to be quite adequate for them....

Regards,
Ray L.

[ataxy]

i know, and i find it a limiting factor to unless you always work with part that are never thicker then 4.995''

[philbur]

Yes but a Bridgeport also has a knee with something in the region of + or - 16" of Z travel.

edit: The discussion is regarding the inadequacy of CNCing the 5" quill travel. It is my impression tha most serious CNCers of a Bidgeports CNC the knee.

Phil

"by the way that 5'' of travel is a bit ridiculous in my point of view" - You do realize even a Bridgeport has only 5" of quill travel? Seems to be quite adequate for them....

Regards,
Ray L.

[SCzEngrgGroup]

Yes, and the machine we're talking about here also has a moveable head, with max of 18" from spindle to table, so I'm guessing the head has about 11" of travel. It's not a knee, but so what? It performs the same function. So what's the problem?

Regards,
Ray L.

[philbur]

See the edit to my past post.

At the end of the day a quill is for drilling not for increasing your reach when milling, at least not if you are trying to achieve your best work. The point is that the machine under discussion should have the head cnc'ed for Z travel not the quill.

Phil

Yes, and the machine we're talking about here also has a moveable head, with max of 18" from spindle to table, so I'm guessing the head has about 11" of travel. It's not a knee, but so what? It performs the same function. So what's the problem?

Regards,
Ray L.

[SCzEngrgGroup]

See the edit to my past post.

At the end of the day a quill is for drilling not for increasing your reach when milling, at least not if you are trying to achieve your best work. The point is that the machine under discussion should have the head cnc'ed for Z travel not the quill.

Phil

Again, the vast majority of Bridgeport CNC conversions move the quill, not the knee, including nearly all, if not all, of the factory-built CNC machines. It's easier, cheaper, faster due to the much lower mass being moved. There are those, like me, that choose to CNC the knee, but either way works fine. When you change tools, you *have* to move something to compensate for tool length. Whether you move the head/knee, the quill or both, to compensate is really just a matter of personal preference. There is no single "best" way to do it. For every argument one person can make to do it one way, another person can make an equally valid counter-argument for doing it another way.

Regards,
Ray L.

[philbur]

I have to give way to your greater knowledge. However, so that I can leave this thread knowing more than when I entered can you give the reasons why you personally prefer to CNC the knee and not the quill. It's not intended as a catch question but an honest interest in improving my understanding. I though I had a good grasp of the limitations of a CNC'ed quill but now I am not so sure. Is it possibly that a CNC'ed quill on a Bridgeport is the least painful solution for a machine that was never designed to be CNC'ed. It seems that a 3 axis (quill) CNCed Bridgeport gives up a lot of its jack of all trades nature in order to meet a more narrow, specific production purpose.

Phil

Again, the vast majority of Bridgeport CNC conversions move the quill, not the knee, including nearly all, if not all, of the factory-built CNC machines. It's easier, cheaper, faster due to the much lower mass being moved. There are those, like me, that choose to CNC the knee, but either way works fine. When you change tools, you *have* to move something to compensate for tool length. Whether you move the head/knee, the quill or both, to compensate is really just a matter of personal preference. There is no single "best" way to do it. For every argument one person can make to do it one way, another person can make an equally valid counter-argument for doing it another way.

Regards,
Ray L.

[SCzEngrgGroup]

Phil,
It's all trade-offs. CNC'ing the quill is mechanically rather complex, but due to the smaller mass, lesser friction, etc., allows use of a smaller motor, and allows greater acceleration and speed. CNC'ing the knee is mechanically very simple, but requires a very strong motor, and speed will be limited, due to the enormous weight and friction in the knee. As an example, my X/Y axes will move well over 300 IPM. The same motor on the knee, even with an additional 4X reduction, is only good for about 70 IPM. I originally intended to do my quill, but doing the knee was so easy (I did it in a single day), it was the quickest means to my end. Eventually, I will do the quill as well. When I do that, the knee will be used for tool length offsets, and most of the actual "work" will be done with the quill. There are relatively few jobs where a single tool is required to move more than 5" in Z. In fact, I've never had one that came close.
Unless you have a tool changer, CNCing the quill makes perfect sense, since you will have to manually set tool offsets anyway, and you can do that just fine with a manual knee. Some will argue the quill will provide better accuracy (due, presumably, to inaccuracies and slop in the Z axis ways), others will argue that the knee will (due, presumably to slop in the quill bushings when the quill is extended). Really, it depends on your specific machine, and your specific requirements and expectations.
There are a number of threads on the Bridgeport forum where you can read all the arguments for and against both methods. As far as I can tell, it comes down to personal preferences as much an anything else. I don't think either approach is inherently better or worse than the other.

Regards,
Ray L.

[philbur]

Ray thanks for that.

I guess it has corrected my simplistic view in that there isn't one single correct answer, at least not for a Bridgeport, which of course I should have realized from the outset. One last question for anybody. In my limited view of the CNC world I have never come across a VMC with a quill. Do they exist, or are the two equally valid solutions for a Bridgeport only applicable because of the weight of the knee.

Regards
Phil

Phil,
It's all trade-offs. CNC'ing the quill is mechanically rather complex, but due to the smaller mass, lesser friction, etc., allows use of a smaller motor, and allows greater acceleration and speed. CNC'ing the knee is mechanically very simple, but requires a very strong motor, and speed will be limited, due to the enormous weight and friction in the knee. As an example, my X/Y axes will move well over 300 IPM. The same motor on the knee, even with an additional 4X reduction, is only good for about 70 IPM. I originally intended to do my quill, but doing the knee was so easy (I did it in a single day), it was the quickest means to my end. Eventually, I will do the quill as well. When I do that, the knee will be used for tool length offsets, and most of the actual "work" will be done with the quill. There are relatively few jobs where a single tool is required to move more than 5" in Z. In fact, I've never had one that came close.
Unless you have a tool changer, CNCing the quill makes perfect sense, since you will have to manually set tool offsets anyway, and you can do that just fine with a manual knee. Some will argue the quill will provide better accuracy (due, presumably, to inaccuracies and slop in the Z axis ways), others will argue that the knee will (due, presumably to slop in the quill bushings when the quill is extended). Really, it depends on your specific machine, and your specific requirements and expectations.
There are a number of threads on the Bridgeport forum where you can read all the arguments for and against both methods. As far as I can tell, it comes down to personal preferences as much an anything else. I don't think either approach is inherently better or worse than the other.

Regards,
Ray L.