# First Milling Machine Choice:  PM 833T or 835S?



## ACHiPo

I'd really like to get a mill.  After thinking about getting a better drill press to replace my Atlas bench-top, I looked at drill presses.  Then started looking at the bench-top models from Weiss, and the WMD30 looked like it it would be a great drill press and get me started on machining.  Then I read about the PM833T and THAT seemed like the bees knees.  Along comes the 835S and I'm thinking it's perfect for me. (See a trend?)

So, why do I want a mill?
1)  So I can drill big holes in stuff (the Atlas belt slips or motor stalls when trying to drill holes approaching 1")
2) To learn about milling:  to make faces of things flat and square
3) To repair and/or make parts for my Cobra replica

I have limited space in my shop (a good sized 2-car garage), and multiple hobbies (woodworking, auto repair, metal working), so I decided on a strategy of putting everything on mobile bases.  This is working very well for me, and I plan to put the mill on wheels as well.

My plan for the WMD30 or PM833T was to get a sturdy steel cabinet with drawers that I could augment with a steel frame with casters--voila a mobile mill with storage space for tooling.  I still like this idea, although have pretty much dismissed the WM25 as too small.  ThePM833 would be about 1100 lbs on cabinet full of tooling, which I figure is about as massive as I want to try to wheel around.

The new 835S appears to have all the feature of a Bridgeport clone, but at 3/4 size (and weight).  The weight's about the same as the 833, but instead of extra storage, I get 17" of Z travel.

I've read the multiple recommendations to just buck-up and get a Bridgeport.  Given my interests, I just don't want to make that much of a commitment to a mill.

I'm not in any hurry, so I'm not terribly concerned that Matt only has a drawing of the 835 at this point.

Thoughts?  Comments?  I definitely want 3 axis DRO, but how many axis auto-feed?  What about chuck choice?  Collets?  Vise?


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## mikey

Man, every time I look at the PM site I get to drooling! 

I would seriously consider that 835S. What I especially like is that it has a real knee on it. That allows you to keep the quill retracted for maximum rigidity/accuracy and raise the work like a real mill. The tilt and nod is not usually used all that much but it makes tramming a whole lot easier than trying to shim a column. Very importantly, it looks like the spindle runs in a cartridge, as opposed to running in bearings held in the head casting. This is a more rigid and precise arrangement and just on this basis and the knee, I would opt for the 835S. 2HP is enough for most jobs you'll do on this size mill; if it had VS, that would be awesome and I have to wonder if the model to follow will have this option - might ask Matt. It gets up to 2720 rpm - very useful for small cutters and carbide tooling.

This mill has an R8 spindle taper so all the common stuff will fit it - collet chucks, collets, drill chucks, etc. The table looks just about right for a 5" vise but I bet even a 6" will fit okay - you have 9" of Y-axis travel. I would probably opt for the 5" vise, though. 

If you can swing the DRO, that would be awesome. You want (as opposed to need) at least an X-axis power feed. I'm not so sure you need power on the other axes but will let others who have it chime in. To my thinking, I would get the X-axis feed and use the money that would have gone to a power feed on the other axes to accessorize the mill. It would be nice if it had power down feed on the quill for boring or power tapping but you can live without it.

Brother, this ain't no drill press! This is one of them wet-your-pants benchtop milling machines and now you got me thinking!


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## ACHiPo

Mike,
Great feedback as always.  I'll give Matt a call next week and ask about availability, power downfeed, and variable speed.
Evan


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## wrmiller

I'll agree with mikey here, in that if you can afford it and have the space a knee mill of whatever size has advantages over a bench/bed mill. Both can do good work, but the knee makes most things easier.

And I'm very jealous. My dream was to get a decent garage shop set up and build a FF5 replica. Things didn't turn out the way I planned (do they ever?) so the only way I'll ever own a replica is for me to build a plastic model of a Cobra.

I did manage to get the lathe and mill I wanted so at least I accomplished something. 

EDIT: Went back and read the description on that new 835, and it says "full featured head". So I'll bet my lunch money it has PDF just like my 935TS.

SECOND EDIT: At the bottom of the page for the 835 (or any of his machines for that matter) there is a 'specification' tab. There Matt specs the 3 speeds for the PDF and says there are 8 speeds for the spindle (belt). So the head is basically like mine on the 935TS. Wouldn't be surprised if he's sourcing the head from the same factory.

Put a VFD on that thing like I did my 935 and you have variable speed belt drive without all the mechanical contrivances of a Reeves drive.


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## ACHiPo

Bill,
I hear you regarding the Cobra bug.  I came very close to starting a project 17 years ago--in fact if I'd had my checkbook with me when I visited ERA I would have written a down-payment check.  After one ride in an ERA I was hooked.  Well, life happened, and it's just as well I didn't go through with it as I would have had to sell it 3 years later due to a divorce (and it likely wouldn't have been completed so that woulda been expensive and difficult, although come to think of it if I HAD pulled the trigger, the divorce would have come much earlier, so a guy never knows ).  Fast-forward 13 years and I get relocated to CA from OR and end up with a 3-car garage AND a 2-car former guest cottage aka shop (with flowered wallpaper and ugly vinyl), so after getting settled and somewhat set up, I began restarting previous passions like audio, woodworking, cars, and now metal working.  At some point I hope to get rid of the vinyl and walls and turn it into a proper man cave, but I digress.  Hope you can figure out a way to at least some time with a Cobra--there's an active community of enthusiasts in AZ, and I know I love giving someone a ride whenever I can.  (By the way my daughter's boyfriend's parents are in Sierra Vista just up the road from you).

I suspect you're right about the head--it sounds like a standard set of pulleys with a belt (not a fan of that or the mechanical variable speed Reeves drive).
By the way, what does the "spindle down feed in 3 steps" mean?  Does it have a powered downfeed?  Edit:  Now that I re-read your post above I realize that PDF means power down feed not an adobe document.   The 835S is looking better and better!


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## wrmiller

ACHiPo said:


> Bill,
> I hear you regarding the Cobra bug.  I came very close to starting a project 17 years ago--in fact if I'd had my checkbook with me when I visited ERA I would have written a down-payment check.  After one ride in an ERA I was hooked.  Well, life happened, and it's just as well I didn't go through with it as I would have had to sell it 3 years later due to a divorce (and it likely wouldn't have been completed so that woulda been expensive and difficult, although come to think of it if I HAD pulled the trigger, the divorce would have come much earlier, so a guy never knows ).  Fast-forward 13 years and I get relocated to CA from OR and end up with a 3-car garage AND a 2-car former guest cottage aka shop (with flowered wallpaper and ugly vinyl), so after getting settled and somewhat set up, I began restarting previous passions like audio, woodworking, cars, and now metal working.  At some point I hope to get rid of the vinyl and walls and turn it into a proper man cave, but I digress.  Hope you can figure out a way to at least some time with a Cobra--there's an active community of enthusiasts in AZ, and I know I love giving someone a ride whenever I can.  (By the way my daughter's boyfriend's parents are in Sierra Vista just up the road from you).
> 
> I suspect you're right about the head--it sounds like a standard set of pulleys with a belt (not a fan of that or the mechanical variable speed Reeves drive).
> By the way, what does the "spindle down feed in 3 steps" mean?  Does it have a powered downfeed?  Edit:  Now that I re-read your post above I realize that PDF means power down feed not an adobe document.   The 835S is looking better and better!



When I moved from SoCal to the Bay Area (Mission Hills, SJ 1991-2000) I quickly got into track events. Built a nasty little gen3 RX-7 that could smoke the M3 tube-framed race cars at Laguna Seca. Then started playing with my Saleen and started doing time trials (Solo 1) at the various tracks in the area. The RX-7 was like a surgeon's scalpel on the track. Smooth was the trick to fast lap times in that thing. The Saleen on the other hand was like a bull-in-a-china-shop on steroids. The Saleen would post faster lap times everywhere except Laguna (more technical track), but man, hustling that thing around for a few laps was very tiring. 

At one Solo 1 event I was given the opportunity to do some test laps in a Factory Five race car. Didn't stop grinning for days. Wanted one REAL bad. Won't happen now, but that's OK. Not everything turns out the way we'd like them to. 

I read the specification sheet on that 835 and it does indeed have power down feed. With three different feed rates, just like my 935TS. It has a 2hp motor (according to the spec sheet). I don't see a 3-phase offering on the motor which would allow you to install a VFD and have the best of both worlds. You may be stuck with the stock 8-step spindle speeds. Not that this is a bad thing.


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## ACHiPo

wrmiller said:


> When I moved from SoCal to the Bay Area (Mission Hills, SJ 1991-2000) I quickly got into track events. Built a nasty little gen3 RX-7 that could smoke the M3 tube-framed race cars at Laguna Seca. Then started playing with my Saleen and started doing time trials (Solo 1) at the various tracks in the area. The RX-7 was like a surgeon's scalpel on the track. Smooth was the trick to fast lap times in that thing. The Saleen on the other hand was like a bull-in-a-china-shop on steroids. The Saleen would post faster lap times everywhere except Laguna (more technical track), but man, hustling that thing around for a few laps was very tiring.
> 
> At one Solo 1 event I was given the opportunity to do some test laps in a Factory Five race car. Didn't stop grinning for days. Wanted one REAL bad. Won't happen now, but that's OK. Not everything turns out the way we'd like them to.
> 
> I read the specification sheet on that 835 and it does indeed have power down feed. With three different feed rates, just like my 935TS. It has a 2hp motor (according to the spec sheet). I don't see a 3-phase offering on the motor which would allow you to install a VFD and have the best of both worlds. You may be stuck with the stock 8-step spindle speeds. Not that this is a bad thing.


Bill, 
You've got a lot more experience with these things than I do.  The only race track I've been on was running Rotax go karts.  I hope to take my "starter" Superformance Cobra up to Thunder Hill for a beginner's class this fall just to test its (and my) limits in a relatively safe environment.  My "final" Cobra will start construction in September and plan to have it completed and on the road by May of 2018.

I checked out your new digs--looks like you've still got a nice set up.  I wouldn't be surprised if you couldn't generate a build a nice little business--it seems there's always a need for machining, although I'm not sure how willing folks are to pay a fair price for it.

I was wondering how to do variable speed with a single phase motor--I guess I don't.  It will be interesting to see what Matt has to say next week.
Evan


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## wrmiller

Many people are too greedy, in that they want top shelf quality for Harbor Freight prices. Had a 'gentleman' ask me to basically build him a $6000 full-on custom pistol with months of work involved, but he wanted it for $2k. My first impulse was to kill the idiot and put his head on a pike out front as a warning to other idiots, but then I realized that we've not been allowed to do that since the medieval days...  

Never drove a Rotax. I did scare myself silly on the front straight at Willow Springs in a 250cc shifter cart. Something about doing triple digits, a few inches off the pavement, and looking between your feet to see where you're going. Right then I decided those guys are nuttier than the guys road racing on two wheels and dragging a knee in the corners (did that too for a bit).

If the 835 has a 2 hp single-phase A/C motor, then you're pretty much stuck with what you get, unless you decide to change motors. Which depending on personal preferences, may or may not be worth it. 

Let us know what Matt says about the new mill?


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## mikey

wrmiller said:


> Put a VFD on that thing like I did my 935 and you have variable speed belt drive without all the mechanical contrivances of a Reeves drive.



Hey Bill, did your 935 originally come with 8-speed pulleys? If so, how well did that work for you? Was it restrictive enough that it made you go to a 3ph VS setup?

I ask because this mill looks to be almost the ideal hobby class mill. In my mind, the only thing that it lacks is a VS motor but that might be an issue only in my mind, hence my questions. If a VS model is forthcoming, it might be worth the wait because while you can add VS later, it isn't that cheap to do if you use quality components, and it won't be covered under a warranty. Optionally, if Matt agrees to upgrade the motor at a reasonable cost if it becomes available later then no waiting is required.

It is not fun living vicariously through your experiences ... . Let's see - Evan, Bill, @Ulma Doctor, @darkzero - I hate all you guys!


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## ACHiPo

mikey said:


> It is not fun living vicariously through your experiences ... . Let's see - Evan, Bill, @Ulma Doctor, @darkzero - I hate all you guys!


Says the man living in paradise with a shop!


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## mikey

ACHiPo said:


> Says the man living in paradise with a shop!



Hmm, there is that ...

I forgot @Alan H  - hate him, too!


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## ACHiPo

mikey said:


> This mill has an R8 spindle taper so all the common stuff will fit it - collet chucks, collets, drill chucks, etc. The table looks just about right for a 5" vise but I bet even a 6" will fit okay - you have 9" of Y-axis travel. I would probably opt for the 5" vise, though.


Mike,
Used 6" Kurt vises are pretty  common,  5" not so much.  Why would you recommend the 5" over 6"?  I assume it's money well spent to go for a top quality Kurt vise, or would I be ok with a good quality import like Glacern?
Evan


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## wrmiller

mikey said:


> Hey Bill, did your 935 originally come with 8-speed pulleys? If so, how well did that work for you? Was it restrictive enough that it made you go to a 3ph VS setup?
> 
> I ask because this mill looks to be almost the ideal hobby class mill. In my mind, the only thing that it lacks is a VS motor but that might be an issue only in my mind, hence my questions. If a VS model is forthcoming, it might be worth the wait because while you can add VS later, it isn't that cheap to do if you use quality components, and it won't be covered under a warranty. Optionally, if Matt agrees to upgrade the motor at a reasonable cost if it becomes available later then no waiting is required.
> 
> It is not fun living vicariously through your experiences ... . Let's see - Evan, Bill, @Ulma Doctor, @darkzero - I hate all you guys!



My mill is the 935TS (Taiwan made, step pulley version), and to be honest I ordered it specifically with the 3-phase motor and the VFD that Matt sells because I had already gotten bit by the variable speed bug when I converted my Charter Oak to belt drive & VFD.

Step pulley BPs (and others) have been used for years. To use, I would select the best possible speed, and then vary DOC and feed rates to get a good cut/finish. While not eating cutters.  The adjustable spindle speed just adds yet another variable to help with tool life and part finish. It is a luxury, not a requirement IMO.

EDIT: On the vise question, this IMO is more of a personal preference than any kind of specific requirement. I managed to trip over a 5" Kurt in very good shape for my 935. Had that not happened, I would have still gone with the 5" as I don't care for all that extra weight of a 6" hanging off the front of the table. So, to compromise, I use oversized 6" jaws (stepped of course) in a 5" vise and get the clamping range in X without all that extra weight/size in Y that you get with a 6" vise.

Just my thoughts on this. YMMV...


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## wrmiller

ACHiPo said:


> Mike,
> Used 6" Kurt vises are pretty  common,  5" not so much.  Why would you recommend the 5" over 6"?  I assume it's money well spent to go for a top quality Kurt vise, or would I be ok with a good quality import like Glacern?
> Evan



Glacern makes a good 5" vise. I was seriously looking at these until I tripped over the used Kurt 5" for sale.


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## ACHiPo

wrmiller said:


> My mill is the 935TS (Taiwan made, step pulley version), and to be honest I ordered it specifically with the 3-phase motor and the VFD that Matt sells because I had already gotten bit by the variable speed bug when I converted my Charter Oak to belt drive & VFD.
> 
> Step pulley BPs (and others) have been used for years. To use, I would select the best possible speed, and then vary DOC and feed rates to get a good cut/finish. While not eating cutters.  The adjustable spindle speed just adds yet another variable to help with tool life and part finish. It is a luxury, not a requirement IMO.
> 
> EDIT: On the vise question, this IMO is more of a personal preference than any kind of specific requirement. I managed to trip over a 5" Kurt in very good shape for my 935. Had that not happened, I would have still gone with the 5" as I don't care for all that extra weight of a 6" hanging off the front of the table. So, to compromise, I use oversized 6" jaws (stepped of course) in a 5" vise and get the clamping range in X without all that extra weight/size in Y that you get with a 6" vise.
> 
> Just my thoughts on this. YMMV...


Bill,
Educate me--what's the downside of the larger vise?  Never having had a mill, I don't have a personal preference, so I'm trying to guess what I'll like best.  I don't follow the concern about additional weight and size in Y, especially given that the table probably weighs 300 lbs?  I know on bench top machines with limited Z the beefier >4" vises chewed up too much space and 3" vises were recommended.

Thanks,
Evan


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## mikey

ACHiPo said:


> Mike,
> Used 6" Kurt vises are pretty  common,  5" not so much.  Why would you recommend the 5" over 6"?  I assume it's money well spent to go for a top quality Kurt vise, or would I be ok with a good quality import like Glacern?
> Evan



I have an 8" wide table on my mill and use a Kurt D40 4" vise. The table slots are perfectly positioned to accommodate the vise without protruding into the Y-space and there isn't all that much hanging out on my side either so the 4" is perfect for my RF-31. I could have gone with a 5" but that would have projected into the Y-space a bit too much and there are times when you need every single bit of room you can get. 

I think a vise needs to be as big as you can comfortably fit on the table without being intrusive in any other way. The 835S has 9" of Y-travel (as opposed to my 7") and you can comfortably fit a 5" vise. It may even take a 6" vise but do you really need the width? I would bow to the experience of others as I do not own a 6" vise but I do know that it would be too big for my 8 X 28" table. So far, the little 4" has been more than wide enough for my needs. 

The more I see and hear about Glacern vises, the more I think it is a very good option. It can be had for a better price vs a Kurt and it is supposed to be just as accurate as a Kurt. When/if I get another mill, I will try a Glacern vise so I can see for myself but you might want to ask other owners what they think. 

There are cheaper options, too, Evan. I don't have personal experiences with the Chinese products but have seen too many comments about surface grinding the base to make it flat or otherwise having to correct defects. Not for me, I'm afraid. The vise is too damned important.


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## mikey

Thanks, Bill. My mill has 12 speeds and it is a hassle to stop and change belt positions. I have a Baldor 2HP 3ph motor that will go on it when I find the time. I want VS not because of the belt hassle. I want it so I can adjust speed on the fly because I know how that affects the quality of the cut.


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## wrmiller

ACHiPo said:


> Bill,
> Educate me--what's the downside of the larger vise?  Never having had a mill, I don't have a personal preference, so I'm trying to guess what I'll like best.  I don't follow the concern about additional weight and size in Y, especially given that the table probably weighs 300 lbs?  I know on bench top machines with limited Z the beefier >4" vises chewed up too much space and 3" vises were recommended.
> 
> Thanks,
> Evan



To many, there is no 'downside' to a larger vise. And that's fine. I'm just different and like to think things through on my own. Having said that...

I want a vise that is of a proper size such that it does not detract from the Y axis travel. Also, I like  to position the vise such that the reference jaw is near the center of the table as most of what I do is relatively small (gun/pistol work, work jigs, various small projects) and I prefer the saddle centered as much on the knee as possible. I then will periodically move the vise fore and aft to distribute the movements across a larger portion of the ways on the knee. A smaller vise allows me to do this and not detract much from my Y-axis travel, nor overhang too much over the front of the table. A 6" vise may only weigh 80 or 90 lbs, but with it not centered on the table you will bias the weight distribution on the saddle/knee way interface to some degree towards the front. How much the table weighs doesn't affect the imbalance. It's simple math.

Left like this for a number of years this will produce slightly more wear bias on the ways near the front of the saddle. How much, I cannot say. But it is something I think of and wish to avoid. I want my machines to last as long as possible. Or at least as long as I do. 

Also with a larger vise, you can literally clamp a work piece large enough such that it literally is unsupported by the table if you are machining near the moveable jaw. I'm not saying there is anything wrong with that, but I won't do it. IF I am working on a piece that large, it will be clamped to the table, centered and the vise will be on a shelf somewhere.

Lastly, I am getting older and I have no desire to drag a 6"x8" Kurt on and off my mill. Especially since I have no burning need to do so. While I do make good use of the oversized jaws when working on pistol slides and such, I rarely need a vise that opens more than 5". And when that rare instance happens, I have a set of jaws I made that are taller and can be used on the outside of the fixed and movable jaws.

There is no 'right' or 'wrong' here, just choices. Make it based on what you want to accomplish and how, not on what I or others tell you.


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## mksj

Similar comments to above, 835TS 3 phase with a VFD, otherwise the TV if RPC, or single phase TV version if no RPC or VFD. No substitute for size, if the budget and space allows. The 935 gives you work size of a full size knee, in a more manageable size and weight. Personally I prefer a 6" vise, something like the Kurt DX6, the reason many people go with a 5" is to see they can see the Y axis dial which is not an issue with a DRO,. Go 3 axis with a separate quill DRO, or 4 axis.  When you get into speed handles, parallels, etc. there is a much larger selection for 6" vises. I am a feather weight at 150Lbs, but still manage to get my 85lb 6" vise and 140lb rotary table on the mill table. But working smart, get a rolling table and set the mill table to the same height so you are just rotating from the mill table to the rolling table. Read the 935 reviews, 99% have given rave reviews, the 1% would probably not be happy no matter what the price. Lots of postings, read these as to what others have done/tooled up. I did end up with a full size knee mill, the numbers worked out better for what I wanted, but it is a bear to move.


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## ACHiPo

Heard back from Matt.  Mechanical variable speed will be an option on future shipments, but not electronic.  Sounds like he will outfit a 3 phase and VFD if you want.


Sent from my iPhone using Tapatalk Pro


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## mikey

I would opt for a VFD if I bought this machine.


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## mksj

To be clear, QMT sells you a 3 phase mill and a VFD, not one installed or how too instructions. You need to get additional parts, switch gear, wiring, etc., install it yourself and program the VFD. Not too difficult, but it is not a turn key system. There are also factors such as adding a power drawbar and other aspects that differ between the TS and TV models. The simplest is the single phase 935TV which would be plug and play, but the 3 phase 935TS should be more durable over the long hall, and a VFD has many nice features like soft start and braking. Long term single phase motors can have problems with their start/run capacitors in particular if started and stopped frequently. 

On the DRO, the 3 axis ES-12B works very nicely with this mill. Installing it yourself saves some $$, and is a good learning experience, but it may take 2-3 days to figure it out.

Some recent relevant threads, but you can dig through the PM forum for additional comments on the 935
http://www.hobby-machinist.com/threads/new-pm-935-coming-soon.54137/
http://www.hobby-machinist.com/threads/saunders-power-drawbar-kit-on-a-pm935tv.56209/
http://www.hobby-machinist.com/threads/maxi-torque-rite-and-the-pm935tv.55486/
http://www.hobby-machinist.com/threads/quill-dro-for-a-pm935.60162/#post-497796


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## ACHiPo

Thanks.  I think I'll just go with the stock single phase machine with pulleys.  When/if the motor dies I can contemplate a 3-phase with VFD.

I'm inclined to get the DRO and X feed installed, but we'll see.


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## wrmiller

ACHiPo said:


> Thanks.  I think I'll just go with the stock single phase machine with pulleys.  When/if the motor dies I can contemplate a 3-phase with VFD.
> 
> I'm inclined to get the DRO and X feed installed, but we'll see.



The power feed (PF) for the X-axis is easily installed, if you want to save a few bucks or just want to do it yourself. It is definitely worth having though, as it makes long(er) cuts along the X-axis so much easier (and better looking). If Matt will install the DRO for you, it would save a few headaches. And, if anything goes wrong it's on him. 

If the head is like mine, changing speeds is not a big deal really. While I mostly leave mine in the middle of the range and use the speed pot on the VFD, it only takes a few seconds to loosen the motor, pivot it slightly, and slip the belt onto a different ratio. Because I very seldom do it, I have a harder time remembering how to change from hi to low range. 

Of course you will be required to post copious amounts of pics if you buy this new mill...


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