Mini Mill vs Round Column Mills

For the last couple of months there has been a guy trying to sell a Hardinge horizontal with a Bridgeport head mounted to it for $1800. Seems like a good deal if the two units are in good shape and how the head was mounted is good. It’s funny that there have been drill/mills come and go(presumably sold) for around that. For me it’s just a curiosity because even though it’s pretty close to the size of my rig I can’t justify the expense. Bridgeport heads come up every once in a while in the LA CL.
 
Something to consider when looking at any mill is the amount of Z axis travel.
When I was looking for my mill I discovered that the amount of Z travel was about 13". That seems like plenty but when you add a vise, and some kind of tool holding, the 14" is quickly used up.
As an example, distance from the table to the top of my 4" Glacern vise is 3.625".
I use a ER32 collet chuck which takes about 1.75". My drill chucks are are even longer at about 3". Add in stick out for the tool and it's easy to lose another 3" to 6".

My mill/drill has 19" from the spindle nose to the table.
 
Chandler -
You were asking about work envelopes and vises. Here's what my mills have:

Harbor Freight 44991 mini-mill: X9.0", Y4.10", Z10.30" (X&Y slightly less than factory, because of a DRO and X axis power feed I've added). Vise is a Little Machine Shop (3767 or 3257) "screwless" style. Bottom of workpiece is 1.07" above the table when held in the in the vise.

Grizzly G1007/RF-30 round column: X17.77", Y7.25", Z5.54"(quill) + 10.75"(head). X is slightly less than factory. Vise is a 5" Enco, minus the rotary base (which would cause a loss of about 1.4" of Z). Bottom of workpiece is 2.53" above the table when held in the in the vise. I once bought a 6" Kurt through Craigslist, but it was significantly too large for the mill, so I re-sold it.

Photos: (1) LMS vise, (2) Enco vise (held in LMS vise on mini-mill) while I was adjusting the ears. Probably shoulda done this on the Grizzly, but I couldn't figger a way to hold the vise in itself :)
kHPIM1082.jpg
kHPIM3492.jpg
 
You've all swayed me... This place is a bad influence on my wallet! This came up for sale in my area for $800, I'm going to pick it up Friday. The vise is total cheese grade but the machine looks nice.
 

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It's a good mill and can be accurized to perform quite well. I suspect you will be surprised at how capable it really is.
 
Well done.
Gents, time to get serious and spend some of his money!


Sent from my iPhone using Tapatalk
 
hman said:
Enco vise (held in LMS vise on mini-mill)
Click to expand...
Great photo — makes me think of the old circus strongman posters as he balances an elephant on his shoulders or something... :)
Question on your LMS vise: I notice a series of hash marks along the top ledges that I’m guessing were scribed in by the clever John Herrmann to remedy some annoying shortcoming. I’ve never seen them on any other vises. Care to expand on their purpose?

-frank
 
Happy to do so. This was part of an extensive mod to the vise I did in 2009. Unfortunately, the Yahoo mini-mill group whare I posted the description is now history. I did describe most of the changes in this HM post in 2017:
https://www.hobby-machinist.com/threads/screwless-precision-vises.55048/#post-455018 - post #10.
The lines were scribed to give me some indication of which hole to put the cross pin thru for a given range of movable jaw positions. Turns out I don't use them that often. I just take out the cross pin, slide the movable jaw against the workpiece, take out the workpiece, and look for which hole is closest.
 
I was wondering if based on the images anyone could tell me if I'm dealing with an RF-30 or RF-25? Mostly just so I know how much weight/physical size I should expect to be dealing with. I was also wondering what the base of these machine measure so that I can start searching for an appropriate piece of furniture to mount it to, I was thinking some kind of rolling tool box would be nice if I could find one of the appropriate dimensions
 
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