Considering a PM-833T or maybe a PM-935TS 3PH

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I'm new here and about to pull the plug on a new mill. The 833T is a better fit for my budget and my floor space. However, the 935TS 3P is inticing and I would enjoy building a simple VFD system for it. I read Dave's comparsion between the two. Other than the 833's lacks PDF and no nod adjustment , it seems to be a well made and capable machine. If I went the 935 route, what VFD do you recommend, where's a good place to buy the other components and what is a good total cost estimate?
 
A lot of us buy the Hitachi VFD from PM with the machine. @mksj is the one who is most knowledgeable about what’s required. But the VFD is about $300 and the remainder of the control components would be anywhere from $200 to $1,500 depending on how many bells and whistles you build into the system (like coolant, E-Stop, spindle light, backgear sensor, depth stop auto-reverse, tapping jog, etc).
 
I don’t have either machine, but my mill doesn’t have a power downfeed and that would be nice to have for boring holes. Some of the holes with my boring head I hand feed on leave a lot to be desired. The other difference is the 933 has a much higher spindle speed, that will be handy if you use smaller end mills in aluminum.

A mill doesn’t need that much in the way of controls, I use three wire control with a DIY pendant that has start, stop, forward, reverse and speed adjustment. I have a Teco L510, it doesn’t have the ability to add a braking resistor, but that is only necessary if you are trying to stop large tooling fast. The internal braking will work in most situations, but stepping up to something that allows for an external braking resistor would be a good idea.
 
I have a 936TS 3PH and love it. @mksj helped me with the VFD setup. I have a few bells and whistles, speed control, two speed braking, fwd and rev jog, back gear sensor and a couple things I don't have completed. I did install a coolant switch and a tach neither of which are complete.

This is my first mill, so, I can't comment on any kind of comparison. I don't have a real break down on the cost of the VFD, I bought supplies to complete two VFD installations at the same time. One for the mill and one for the lathe. I would guess somewhere around 6 to $700 bucks, maybe a little more the way I have mine setup.

Here is a photo of mine, I have since tied up all the cables.

20220406_122132.jpg
 
Hummmm? This looks vaguely familiar. LOL Have you considered replacing that nut-busting Y-axis handle? Have a look here:

 
I struggled with this choice a few years ago and chose poorly. I was concerned with taking apart the 935 to get in the door. With what I know now, I should have got the 935 and took the table off. The 833 can get the job done, I'm just not thrilled with it. If it were me, I would get the 935 if you can afford to.

If you do get the 833, the z power feed is a must. I couldn't imagine how tiring it would be manually raising and lowering the head. Plus you can use it as a power down feed.

Get a vise from Precision Matthews when you buy the machine along with the R8 collets, a drill chuck, clamping set, and boring head. I bought an inserted boring bar to use in the boring head. The rest piece together as you get jobs/needs for them. You'd be surprised what you can run across used. I also got a ER40 holder for the mill from Precision Matthews as I settled on one collet series for the mill spindle, collet blocks, the lathe spindle, and lathe tailstock. So I also got a standard ER40 collet set from them as well.

There's plenty of places to order all the miscellaneous tools that you will need/want and end up spending more on them than the machines themselves. Maritool, Little Machine Shop, Ajax Tool... Read enough posts here, you'll learn new companies to buy and tools you will want.

Like a goober, I got a 5/8 drill chuck for the lathe tailstock and a 1/2 one for the mill... needless to say I wasn't saying nice things about myself when I wanted to use a 5/8" drill in the mill and had to swap the chuck for a reamer when going up in drill size.
 
I have a 936TS 3PH and love it. @mksj helped me with the VFD setup. I have a few bells and whistles, speed control, two speed braking, fwd and rev jog, back gear sensor and a couple things I don't have completed. I did install a coolant switch and a tach neither of which are complete.

This is my first mill, so, I can't comment on any kind of comparison. I don't have a real break down on the cost of the VFD, I bought supplies to complete two VFD installations at the same time. One for the mill and one for the lathe. I would guess somewhere around 6 to $700 bucks, maybe a little more the way I have mine setup.

Here is a photo of mine, I have since tied up all the cables.

View attachment 430373
 
I have a dedicated 240v 20amp 12ga circuit which I think is what the 935 calls for. However, the Hitachi VFD indicates I need 30amp breaker and 10ga wiring for the VFD. Would i be safe staying with what I have?
 
I reread your original post. I probably misunderstood the question about other components... If you were talking about VFD components, I used Automation Direct for everything but the VFD on the lathe. I purchased my VFD from Wolf Automation.
 
I have a dedicated 240v 20amp 12ga circuit which I think is what the 935 calls for. However, the Hitachi VFD indicates I need 30amp breaker and 10ga wiring for the VFD. Would i be safe staying with what I have?

I don't think I would chance it but I suppose in the worst case it would just to the circuit breaker.
 
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