New to me RF-45 help

[Kscar3318]

A few months ago I picked up an RF-45 square column gear head mill and I can't for the life of me find much information if any about them. With machining and all being relatively new to me I have a few questions about this mill in particular and would greatly appreciate any help or insight anyone could offer:

1) what's the best way to clean all the gunk and grease and grime off of everything so that I can get a good idea of what Im working with? Anything I should avoid stripping the grease from/if so what and what should I use to replenish it?

2) While trying to tram the head to the table yesterday, I had about a 10 thousandths tilt to the right (if looking at the machine from the front). So I loosened the 3 nuts around the head and tried tapping it with a deadblow and it wouldn't budge. I tried loosening everything I could think of and still the head wouldn't budge? Am I missing something?

3) when I got the mill the depth gauge was broken/missing, does anyone know where I could track down replacement parts?

4) my fine feed seems to have a couple thou of backlash and it will "drop" sometimes during milling causing my parts to be off. Is there any way to tighten that up?

5) general maintenance, what and when should I be doing? I really want to take care of this machine like it deserves but just don't really know where to start other than squirting some oil on the ways every now and than and cleaning the chips off. Thanks for the help!!!

 

[mickri]

Welcome to the forum. We are a friendly bunch. Lots of really knowledgeable people on here that will help you solve your problems. Don't be afraid to ask any question no matter how simple you may think it is. You will get good answers.

You can use just about anything to clean it. Any type of automotive degreaser will work. Once cleaned up mineral spirits in a spray bottle works good to keep things clean. That's what I use on my lathe and RF31 clone.

Sounds like you need to take the mill apart for a good thorough cleaning. You might find some broken/worn parts during the tear down and cleaning.

Quill down feeds are notoriously inaccurate. All kinds of solutions from inexpensive calipers to DRO's with more bells and whistles than you can imagine. The slipping you mentioned is probably cause by dirt and grime not allowing the quill lock to function properly. Or it could be worn. Again a complete teardown and cleaning may solve the problem.

 

[Kscar3318]

Thanks for the quick response!! I tried to take the table and the head off when I first got it and didn't have much luck. That said, since this was my first piece of machining equipment I didn't want to just tear into it without really knowing what I was doing. I'm reasonably comfortable welding and fabricating and with general shop work, but this realm of "precision" equipment is all new to me.

1) What's the best way to get the head off without damaging it? It's a fairly heavy piece I worry about dropping it.

2) how do you disassemble the table? Do you have to loosen a nut for the cross slide from the underside of the machine? If so, I'll have to figure out how to get it off of the stand it's bolted to....

 

[Ken from ontario]

Quill down feeds are notoriously inaccurate.

I thought that the round column ones were supposedly "inaccurate" but this one, (the mill OP has) seems to have a square column, just wondering if the square column RFs are better /much more accurate.
BTW, Kscar3318, welcome aboard.

 

[epanzella]

As far as quill backlash goes you'll never get rid of it but you can work around it. When you lower the quill don't push it into the work Just gently touch to get your zero. Get the work out from under your quill and drop to your desired DOC then lock the quill. Now you can proceed with an accurate cut. Don't expect to plunge accurately without a DRO to monitor the exact quill position. If you can predict the sum of the backlash in the fine feed worm and of the rack with different quill extension values you are a better man than I, Gunga Din.

 

[Reddinr]

I built a cradle for mine that the head will rest on and be supported by. I made it out of 4x4s and 2x4s I think. I just lower the head onto the cradle and unbolt it. From there you can pick it up with an engine hoist or whatever. It is a top-heavy thing so watch it.

For the left-right tram there are just the two bolts to the left and right of the head. It may be rusted or gunked in place.

 

[Kscar3318]

I built a cradle for mine that the head will rest on and be supported by. I made it out of 4x4s and 2x4s I think. I just lower the head onto the cradle and unbolt it. From there you can pick it up with an engine hoist or whatever. It is a top-heavy thing so watch it.

For the left-right tram there are just the two bolts to the left and right of the head. It may be rusted or gunked in place.

Thats what I was thinking about doing, I'll have to go rent me a engine hoist tomorrow, I definitely would rather error on the side of caution. You say there's only 2 bolts what's the 3rd one for?

Also, one lest question, there use to be a small nut here (circled in picture) and when trying to loosen it a while back it snapped off but the bolt is still there. Could this be something that functions as a "lockdown" for the rotation of the head?

Again thank you for all the responses guys!! I've been a long time lurker and I wish I had posted about this machine months ago!

 

[Kscar3318]

As far as quill backlash goes you'll never get rid of it but you can work around it. When you lower the quill don't push it into the work Just gently touch to get your zero. Get the work out from under your quill and drop to your desired DOC then lock the quill. Now you can proceed with an accurate cut. Don't expect to plunge accurately without a DRO to monitor the exact quill position. If you can predict the sum of the backlash in the fine feed worm and of the rack with different quill extension values you are a better man than I, Gunga Din.

Okay I will try that going forward! Thanks! What's a "typical" DOC for this kind of machine? For example, when milling 6061 aluminum I think the most I usually push it with a 1/2" HSS endmill is about .030 or .040 thou. Same setup with mild steel is probably about half that.

 

[epanzella]

Okay I will try that going forward! Thanks! What's a "typical" DOC for this kind of machine? For example, when milling 6061 aluminum I think the most I usually push it with a 1/2" HSS endmill is about .030 or .040 thou. Same setup with mild steel is probably about half that.

My machine is an RF 30 so I can't give you exact values. Different materials, different stick out, different feed rates, different speeds will require different DOC limits. What you quoted is conservative but no one ever hurt a machine by going too easy on it. I'm just a weekend warrior but my machine can talk and it will tell me if it's happy or if I'm pushing too hard.

 

[Reddinr]

I just looked at my mill. I have three large bolts, not two. (Obviously have not trammed my mill in a while. ) I have a bolt located on each side and one on the bottom of the circular mounting plate. It does not have the smaller bolt you circled. If I had to guess, I would guess that the smaller bolt you have is a binding bolt. Does not seem that useful to me.