Re: Yet Another RF45 Build
We want pictures . Keep us informed. My project is on standby. Lack of funds.
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Re: Yet Another RF45 Build
Well it's nearly time to send out the spindle quill assembly to the machinery rebuild service. I'm going to need bearings such as Nachi 7207CYP4 Abec-7.
Then I'll need to start working on the the gas cylinder doohickey, which I don't know exactly how it's configured -- n I know I'll need a 5 gal airtank and the gas cylinder. Need more research. Have to weigh head - I already know the 1.8kW spindle servo weighs about 32 lbs and aluminum mounting brackets, pulleys & so forth for it are about 15, but will weigh the spindle quill assembly soon before I send it to the rebuilder. Then it's time to take down the head from the column at which time I will weigh it. Much work to do on head;
So I'm trying to get a handle on what size servo l need for the Z axis? I can pretty well guess it need not be larger than 1 kW
Re: Yet Another RF45 Build
750 watts for z axis should do just fine.
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Re: Yet Another RF45 Build
Thanks for the reply. Actually I'm going to try to press out the spindle bearings myself, at least. So I'm off to Horror Freight to get a hydraulic press.
In other news we are going to drill & ream the end brackets for the table for 1/4 dowel pins. Going to swing the Bridgeport head round and stand the table upright on the floor I think. Never did anything like that before so in a few days I'll post pictures of that operation. Unusual setup to say the least. Then later will drill and ream for dowel pins in the base for the Y axis as well, which will also be an unusual setup on the Bridgeport. As you all know the asians used taper pins (and some weren't even perpendicular !!) so the idea is to get rid of them and replace with proper dowel pins. I may or may not do that on the top of the head ... don't know yet.
*side note: well my local Harbor Freight couldn't accept any credit cards; their machine was broken so I couldn't buy the 20 Ton Press. Didn't have my 20% Off coupon with me anyway so... so-much-the-better.
well here's a photo milling the grooves in the non-gib angled faces of the dovetails (the oil circuit of the adjacent flat supplies the angled face as well):
https://www.cnczone.com/forums/attac...d=406032&stc=1
Re: Yet Another RF45 Build
So the next problem will be how to accurately locate the X & Y brackets for the ball nuts. I imagine I can install the supports and ball screws and then take measurements from the ball screw to the flat of the dovetail. But that only gives me Z. Looking at the photo above in post #5, getting the Y dimension on the saddle is the problem. How do you accurately locate the ball nut bracket in Y and Z directions?
Then you have the same problem for the other axis on the underside of the saddle in the picture above, for an X dimension, and again Z direction.
Re: Yet Another RF45 Build
To remove the lower spindle bearing race there is two small holes drill in the quill. A small driver will work to push out the race.
On the Y slide if you enlarge the little cutaways they cast in for the X end plates you can get a extra inch of travel.
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Re: Yet Another RF45 Build
Quote:
Originally Posted by
arizonavideo
To remove the lower spindle bearing race there is two small holes drill in the quill. A small driver will work to push out the race.
On the Y slide if you enlarge the little cutaways they cast in for the X end plates you can get a extra inch of travel.
Thanks for that tip on the bearing race!
>> "On the Y slide if you enlarge the little cutaways they cast in for the X end plates you can get a extra inch of travel"
You mean these at each end?
https://www.cnczone.com/forums/attac...d=406414&stc=1
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Re: Yet Another RF45 Build
OK -- so day before Thanksgiving, we have the table now affixed to the Bridgeport table ready to locate the hole features, bolt hole features and capture and record these dimensions as well as the location of acme screw relative to the front side dovetail: (notice we have head swung round and we are indicating it in for three planes)
(note: the table is not touching the 2-4-6 blocks or the dolly - they are there for safety in case there is any slippage while we get the setup done)
https://www.cnczone.com/forums/attac...d=406418&stc=1
So the plan is, like I said, to capture the dimensions of the features relative to front dovetail, go back then and drill & ream for 5/16" standard dowel pins and abandon the taperpin ones. Just going to keep the old bolt holes, they're fine. Then I will carry over the captured acme screw dimension/location and the newly added dowel pin locations to the other end of the table, referencing the same front dovetail. That way when I make up the new end plates that should locate the ball screw parallel to the front dove tail in X,Y and Z. Then it remains to find out how to locate the ball nut bracket on the saddle w/ respect to the ball screw.
Does this sound like a good plan?
(hope all of you had a Happy Thanksgiving!)
Re: Yet Another RF45 Build
Almost forgot to add that I have to mill about 1/4" off the "arches" on the ends of the table as the ball nut will not pass under it when it comes time for assembly and or disassembly -- Like a highway tunnel that's too low for a truck! I'm talking about the "roof" of the table that extends in the first 4" from each end of the table. (hope that make sense)
Secondly this is bit more disjointed then I would like i.e. I would have rather documented the work I did on the saddle first, one shot oiler, oil line fittings metering valves etc. And then moving onto each axis. In a progressive logical manner, like reading a book. But the table and the base (Y axis) has to interject and take precedence & be done rather quickly while I have access to a few strong arm friends and their Jet mills - what with the Holiday, then Christmas too. MUST STRIKE WHILE THE IRON IS HOT !! The work in post #9 will resume on Monday. So it's turning into rather a hodgepodge documenting here on CNCZone. Oh well, at least I'm moving forward !!
--- and thank you ALL for all you input, observations and feedback!
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Re: Yet Another RF45 Build
Thinking more on the X axis brackets, apparently Bridgeport used roll pins, aka spring pins instead of dowel pins. Taiwanese imports apparently use no pins at all, just 4 bolts, such as Jet (see picture above in post #9). So I got to thinking that I will just use four bolts on each end. (see the bracket in the attachment below shown in red )
I found that the servo motor mount assembly with the angular contact bearing supports sold by Automation 4 Less just don't work well for a milling machine application. I was looking for a plug n' play arrangement but I can't find any.
<Sigh> So I will have to make the servo motor mounts myself. (shown in yellow):
https://www.cnczone.com/forums/attac...d=406490&stc=1
Basically just a 3" section of 3x3 A500 square tube with a 3/8" thick cap welded on one end and a 1/2" cap welded on the other suitably bored out and drilled on either end. So I have to make two, one for X, one for Y; and a similar but larger one for Z. These motor mount assemblies will then mount to the X and Y brackets shown in red (Y will be a bit different in outer shape naturally, as will Z). I'm trying to get as compact a direct-drive design as I can, so I think this will work out fairly well.
Re: Yet Another RF45 Build
I have the ENCO YZ-7045. Basically an RF-45 with a 2HP 220V Single phase motor.
One problem you're going to run into is "Stick-Slip". Dovetail ways were never designed for oil, They need grease to function smoothly. Without the heavier grease to ease friction under slow movement, your table will stick initially, then jump when torque buildup overcomes resistance.
I have Mach3 , an ESS, and a CNC4PC C-62 BoB
My motors are 900 once/inch with DG4S 08020 drives from CNCDrive.com
Still looking at how to mount the system and retain the manual capability.
Keep us posted.
Re: Yet Another RF45 Build
Quote:
Originally Posted by
Uguessedit
Any updates on your build? Did you go with cyp or BMI bearings? A lot of folks have used the cheaper bearings with success and .0002 runout. Curious to know and see final build.
Haven't checked this thread for a good 2 months or so: actually a while back I was about to quit posting on my build thread because for a long time it seemed no one stopped by, no one cared, so I was about to say "Heck with this, no one cares anyway. I'll just post all of it over on Chaski."
So I'm glad somebody stops in to comment.
Well you have to wait a fairly amount longer to " know and see final build".
I have my day job, so its catch as catch can. If I didn't I could probably do all this by the end of August. And I'd really like to because I really want to start on my 7.5 gauge steam locomotive (2-8-2) ! But the mill MUST come first. I can't afford to be side-tracked (and getting sidetracked, btw is just too easy for me)
I machine parts over at the University makerspace when chance presents itself, for the most part. (otherwise this build wouldn't even be possible unless I bought a second mill). They have a CNC mill I use from time to time
No, not BMI or cyp (not sure what cyp is). Haven't got to the spindle yet - I put that off for just the time being.
So I have the 20 mm 5mm lead ball screws, zero-backlash ball nuts , and FK FF supports. The DMM Dyn4 Servos & drives are received. The Centroid Acorn received. Still need 3 micron limit switches ($60 each) Still have to fabricate the X, Y, and Z, ball nut mounts. Still have to lower hole on front of mill base to accomodate the ball screw arrangement ( Y ball nut mount is taller so the relative position of the Y axis ball screw must be lowered in the -Z direction)
Upcoming will be to install a pair of 75 lb. gas cylinders INSIDE the column per KCJ's build.
Well that's all for now. Not any pictures (YET)
Re: Yet Another RF45 Build
Quote:
Originally Posted by
WHITEHORZE
I have the ENCO YZ-7045. Basically an RF-45 with a 2HP 220V Single phase motor.
One problem you're going to run into is "Stick-Slip". Dovetail ways were never designed for oil, They need grease to function smoothly. Without the heavier grease to ease friction under slow movement, your table will stick initially, then jump when torque buildup overcomes resistance.
.
In fact I've never heard of anyone using grease on manual milling machine ways. Heck as an example, the Bridgeports I use over at the University use an automatic oiler with metering units on each way and a smaller metering units on the ball nuts -- utilizing AW32 way oil. Mine will be a manual pumping unit - maybe someday I will make it automatic. I'm definitely not inclined to use grease because it attracts more grit --- on a total loss oil system the oil eventually washes grit away ( as new oil replaces that which is "lost" )
Stick slip is NOT because of oil vs. grease; it's because of poor lubrication perhaps or poorly adjusted gibs, both perhaps.Maybe the ways are in poor or mediocre shape.
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Re: Yet Another RF45 Build
Well I actually DO have a picture or two.
Here we have the proposed Belt Drive system sporting a 1.8 Kw servo motor.
the spindle drive adapter w/ associated mounted double pulley isn't done yet. Neither is the step pulley on the servo shaft.
Everything else is assembled (except the black adjustment handle)
shout out to arizonavideo for teh belt drive. guys you may want to look to him for a belt drive conversion!
This uses the original cast-iron top to the mill shown transparent (boy that saved me a lot from making a whole new aluminum top - and I was going to! Whew!
https://www.cnczone.com/forums/attac...d=422648&stc=1
the big nut thing you see on top of the front spindle pulley is called a Trantorque made by Fenner Drives. It allows you to fasten a pulley onto a shaft by clamping action - no need for broaching keyways, set screw or anything else. And they are removable and reinstall-able !! And when torqued to spec they can handle way more HP than we'll ever develop.. Check them out! There's one on the Servo shaft /pulley too.
You might ask "what about the draw bar, might it not be tall enough to clear the Trantorque?" Make a new one that is tall enough, not that hard.
The pulleys are 1:1 and there's a 2:1 step too. Requires two different belts to have on hand. Someone (ninefinger) convinced me to retain the 2:1. I didn't think I really needed it - DMM servos have a flat torque curve. But I thought "well it doesn't cost me a whole lost to implement the 2:1 step, so if I ever need it in a situation requiring a lot more power, I can take off the 1:1 belt and slip on the smaller 2:1 belt." If I have to run a tool at say, 600 rpm, with just 5/8 HP available on the 1:1 ratio, for example.
I may need it, perhaps. It's there if I ever need it. Doesn't hurt anything and is not overly time consuming to make.
I really don't see how I'm much worse off now than with a 2 HP 1750 rpm Baldor, VFD and a 2:1 step pulley instead. And then too: as far as the Bridgeports at University: none of them I know of, including the CNC, at 2-1/2 hp go above 3000 rpm or below 250 rpm anyway.
Another point about my shop: This is all about building scale steam engines and small projects - I'm not a job shop (I already have a dang job!! What do I need another one for ?? Besides I'm retiring end of next year). So lighter cuts are the order of the day. I don't care if it takes 1-1/2 hours to do 45 minute job. So what. Not to mention if you're running a slow program takes a long time...well if you're building say a 7.5" gauge steam loco, there many things you can be doing in the mean time -- many!
Food for thought.
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Re: Yet Another RF45 Build
Now notice the spindle drive adapter in previous post (that has the big Trantorque on it !!).
I had to find a spline of some sort to fit the spindle's male spline shaft. Metric 6-23-28. Looked high and low. Sure I could have got one from Europe way expensive but they are very difficult to find here. I definitely didn't want setup a dividing head on my South Bend shaper to cut the internal spline !! Real PIA.
I should have thought of this 6 months ago :
https://www.cnczone.com/forums/attac...d=422650&stc=1 https://www.cnczone.com/forums/attac...d=422652&stc=1
This insert was cut out of a piece of scrap SS on the waterjet at the University !! Turned out nearly perfect within .003". So now all you do is turn a mandrel on the lathe to fit the ID of the spline insert and then turn the OD for a press fit into the spindle drive adapter. Process came in REAL HANDY !! Cost me $14 -- fine by me!! I love it! they have to charge for the Garnet abrasive.
So when I do my 54" long steam loco frames, I'll waterjet them - will SAVE A TON of setups on the mill and machining.
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Re: Yet Another RF45 Build
Well, one more picture....
You can see here the spline insert (light blue) shown above in post #17, pressed into the spindle drive adapter, pointed to by red arrow
https://www.cnczone.com/forums/attac...d=422662&stc=1
You also can get a better look at the pulley arrangement; notice also the Servo/pulley has a 7/8" Trantorque as well. Hidden behind the buttonhead cap screw, but it is there, hard to see. I may or may not the use larger Trantorque on the spindle-just not completely sure, but I am definitely keeping the 7/8"Trantorque on the Servo pulley.
And I may go for a 2:1 and 1:2 step pulley arrangement as originally planned. Don't know. Mulling over. That will be the very last thing to be decided. And even so, I think I will make TWO 2:1 step pulleys during the machining stage and just set one aside. That way if I ever decide that a 2:1 and 1:2 step pulley arrangement is better, I already have the stuff on hand.
Well so long, that's all for now, folks!
Re: Yet Another RF45 Build
Quote:
Originally Posted by
Uguessedit
You can also purchase a 6 spline PTO adapter for $20 off eBay and it’s 3” long to boot. They fit perfect and don’t need to make at that point. I’ve press fit them into pulleys and spindle wrenches and they hold forever. That’s how I’ve made all my spindle collet wrenches.
Have a link to that 6-spline adapter so I know what you are talking about ?
*as an aside when I post a quotation I try not to include all the OP's pictures and so forth, only just the essential pertinent part of the OP's post --- else it needlessly wastes bandwidth, takes up too much room in the thread for redundant stuff. Just sayin.
