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

ACHiPo

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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
 

wrmiller

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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... :D
 
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wrmiller

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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. :D
 

ACHiPo

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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... :D
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
 

mikey

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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.
 

mikey

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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.
 

wrmiller

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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

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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.
 

ACHiPo

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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.


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