Looking for a benchtop mill... found RF-31

better-lathe-than-never

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Found this locally: RongFu-31; looks rusty, and neglected - it needs some work, according to the seller; when I asked he said some of the cranks are bent. I can't tell from the pics but it maybe more than what can be considered a benchtop mill - it looks tall and pretty heavy. Still, it's in my budget and I can probably find room for it (once my wife stops wining at me about buying another piece of equipment with no place to put it...). Looks like it maybe 120V judging from the cord that's hanging in that photo. That round column isn't a big plus either...

It comes with no tooling - which is a bummer. I figure I'll still need: good 5in vice, drill chuck, collets, collet holder (I think they are separate). I have a bunch of mills my dad left me from the Bridgeport knee mill that he worked on - it would be nice if I could use them as they look to be of fine quality. I'm guessing at least $500 for a basic set of tools to start with.

About my work aspirations: I'm just looking to flatten some surfaces with a fly cutter, cut some slots and maybe some v-grooves, make hex bolt heads, splines, etc. Not looking to build a space ship... My work will be mostly in aluminum and mild steel, maybe stainless steel occasionally.

Is it worth spending about $1000-1100 for such a thing and bringing it back to a working order as a starting mill?

Update - you can click on the link above to see the pics.
 
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Pictures if you have them....
 
It looks like a later model 30/31 from the photos.
will need detailed cleaning & oiling.
i have one, I’ve made peace with the round column, I have no problems, you just need to plan ahead. And there‘s ways to deal with that.
it is pretty heavy for a bench top, but the weight works in your favor most of the time, and they are a solid machine.
in todays market I think the price is not bad. maybe bargain a little. 800-1000 wkold be better.
you should be able to use your Dad’s tooling, it has an R8 taper.
YMMV
EDIT: Ask him how he managed to break all the handles
 
In my opinion, that's a perfect mill for hobby use. It all depends on how you feel about cleaning it. A little bit of wd40 and a rag will probably go a long way with this one. I'd probably replace the belts, scrub it with an oily rag and you're good to go.
 
I have a RF 30/31 clone. You can do a lot with it. You can go nuts buying stuff for it. It will either have an R8 or a MT3 spindle. I use ER32 collets for everything on mine because they seem to have the most space when changing tooling. Start slow on buying stuff. Get a 4" machinist vise. Consensus seems to be that anything bigger than 4" is too big. I got my 4" vise from Shars. It came with a swivel base that I made a backing plate for that has the same threads as on my lathe. Very handy for milling stuff at an angle and for drilling precise bolt circles.

I have no idea if $1250 is a decent price. I bought mine years ago and haven't looked at prices for these machines in awhile.
 
Did they leave it out side and the drip pan got full of water or did they run coolant on something and just never drain the pan and that’s why the crusty rust and yuk around the base?

My main concern is the Y ways look dry as a bone. So who knows if they ever lubed the X either. I know he’s going to give the rap that the new ones are $$, but that is probably twice what they paid for it when it was new. Obviously YMMV, but I’d check it over real close like see how much play there is in the X & Y and make sure like the X gib is adjusted and run it from stop to stop and see how tight it gets at the end of travel. That should tell you how much wear is in the X. From my experience one of the the first things you’re going to need besides all the things you mentioned is X drive. That cranking’ back and for gets real old.
 
To me it looks kind rough for $1250.


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I guess it wouldn't take too much to clean it up though. A little steel wool and WD40 would probably go a long way on the machined surfaces.

That is more than I paid for my used 8x30 knee mill ($1000) in similar condition. That was about 5 years ago though... and I looked for many years before I found the 8x30.

Mill1.jpg

It took a few hours to clean off all the rust and make it look respectable. Now that I look at the RongFu and my Husky when I purchased it the RongFu does actually look in considerably better condition than my 8x30 started in.
 
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That machine has good bones, I think. Yeah, it's all rusted but I suspect it was used as a drill press instead of a mill and I suspect the ways are still quite good. His price is a bit high but how high depends on your budget and the cost/availability of machines in your area. I would certainly use the busted handles and bent chip pan as ammo to get him down to $900-1000 where this machine belongs.

If I bought that machine, I would tear it down to the last nut and bolt anyway. An electrolytic bath would take care of everything except the column; that will clean up with WD-40 and extra-fine Scotchbrite. You can probably fix the broken handles yourself if you have a lathe.
 
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