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DeereGuy
12-09-2003, 08:13 AM
I am looing for input from someone who has experience with both of these mills. I am moving from the RF31 to one of the above. I want the repeatability that the dove tail offers. I am going saturday to pick up a RF45 from Wholesale Tool unless I get feedback that there are major drawbacks to the RF45 vs a knee mill.

Thanks

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Bob

JCHannum
12-09-2003, 08:43 AM
I would never recommend a mill drill above a knee mill. If you have the room and budget, get a knee mill.
I am not familiar with the Rong Fu line, and really don't care to be. You are apparently in the Detroit area if you are headed for Wholesale Tools. There are many dealers in the area, down here in Toledo, or Cleveland who can probably fix you up with a good used Bridgeport for the same amount of money.
You are apparently dissatisfied with the RF31 for some reasons. The RF45 will probably still have many of the shortcomings of the 31, or any other mill drill. It will have some advantages, but will still come up short when compared to a good knee mill.

debequem
12-09-2003, 11:25 AM
I also have an RF-31 that I want to replace. You know the story if you own one. I wouldn't put myself through it again with another mill/drill. Why should you?

After sorting through a whole host of choices I am settled on getting a used Bridgeport Series 1.

You can get a much better mill for the money if you find the right Bridgeport. There are a large number of them for sale used since the economy has been forcing many shops to downsize or go out of business. It is a buyer's market, but probably not for too much longer.

Just make sure you evaluate your purchase carefully!

Good luck.

Marv

Excitable Boy
12-09-2003, 11:48 AM
Count me on the list as well. I have an RF-30 in the garage waiting to be picked up by it's new owner. It's Bridgeport Series 1 all the way from here on out. Now I just need to find the right one.

John

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Pursue Excellence and the rest will follow.

DeereGuy
12-09-2003, 01:25 PM
The only grip I have about the RF31 is the round collumn. Loosing the index anytime you raise or lower the head turned out to be a bigger PITA then I had anticipated. Other than that it has served me well and would have otherwise been quit happy with it.



<font face="Verdana, Arial" size="2">Originally posted by JCHannum:
I would never recommend a mill drill above a knee mill. If you have the room and budget, get a knee mill.
I am not familiar with the Rong Fu line, and really don't care to be. You are apparently in the Detroit area if you are headed for Wholesale Tools. There are many dealers in the area, down here in Toledo, or Cleveland who can probably fix you up with a good used Bridgeport for the same amount of money.
You are apparently dissatisfied with the RF31 for some reasons. The RF45 will probably still have many of the shortcomings of the 31, or any other mill drill. It will have some advantages, but will still come up short when compared to a good knee mill. </font>

BillH
12-09-2003, 01:31 PM
Using my HF Micro mill, I realized how nice the dovetail column is on it. I allways heard people bash the round columns, something about losing their setup. After using mine to counterbore holes, I realised, Ah thats what they are talking about. I can move my head up, chuck in the bigger drill or endmill, and lower it down and not have to reset the position!

MAN!, HOw do you guys stand it with those round columns??

DeereGuy
12-09-2003, 01:42 PM
Bill, your fortunate that you can get away with that minimill. My projects were a little to large for it. I startd with the minilate in March. Bought a 9 x 20 in August and now just set up a new WT 13 x 40 gearhead. This one is a keeper.

I just did an ebay search for the Bridgeport the others are talking about and all the ones I seen were about twice what I expected to pay. Live and learn.



<font face="Verdana, Arial" size="2">Originally posted by BillH:
Using my HF Micro mill, I realized how nice the dovetail column is on it. I allways heard people bash the round columns, something about losing their setup. After using mine to counterbore holes, I realised, Ah thats what they are talking about. I can move my head up, chuck in the bigger drill or endmill, and lower it down and not have to reset the position!

MAN!, HOw do you guys stand it with those round columns??</font>

debequem
12-09-2003, 01:55 PM
I would not put much faith in eBay. I regularly see BPs going for under $2,000. I am looking at another one or two tonight.

I don't do large parts, but it isn't hard to exceed the grasp of the mill/drill. Add to that is the fact the mill/drill can't hold a candle to a Bridgeport for robustness and performance. If you can handle the larger machine you should consider doing it and save the RF-31 as a drill press.

Also, try a Bridgeport and see what you think.

You also stated that it cost you three lathes to get the keeper you have now. So, what was the total cost of all three? How much did the last lathe you bought cost (the keeper)? The difference between the two numbers is how much you overpaid.

Were you planning on buying three mills, too?

Not being a smart-butt, I just wanted to look at it from a different angle.

Marv

DeereGuy
12-09-2003, 02:19 PM
Actualy Marv I got lucky with the first two. Both failed within the 30 day return window with Harbor Frieght.

If I got a knee mill it would be in the 8 x 30 table size. I just don't have the room left in my garage/shop for a large BP. And do know where there is an Index for $1000.00 but it is in really rough shape looks wise and is missing some parts plus it is not and R8 Collet.



<font face="Verdana, Arial" size="2">Originally posted by debequem:
I would not put much faith in eBay. I regularly see BPs going for under $2,000. I am looking at another one or two tonight.

I don't do large parts, but it isn't hard to exceed the grasp of the mill/drill. Add to that is the fact the mill/drill can't hold a candle to a Bridgeport for robustness and performance. If you can handle the larger machine you should consider doing it and save the RF-31 as a drill press.

Also, try a Bridgeport and see what you think.

You also stated that it cost you three lathes to get the keeper you have now. So, what was the total cost of all three? How much did the last lathe you bought cost (the keeper)? The difference between the two numbers is how much you overpaid.

Were you planning on buying three mills, too?

Not being a smart-butt, I just wanted to look at it from a different angle.

Marv</font>

sch
12-09-2003, 02:30 PM
Have you looked at the Grizzly G 0519, not
a knee mill but a dovetail drill mill with
a claimed 18" vertical clearance. Has a
"tapping" mode though it is not entirely
clear what this amounts to. Also has a
3phase motor so a VFD would be essential for
most of us, but this seems a clear benefit.
Priced about $1500, and at 6-700#, easy to
move. This machine appeared on the RongFu
web site about 3yrs ago. Steve

JCHannum
12-09-2003, 02:33 PM
The knee mill is a true milling machine. The mill drill, regardless of upgrades is a glorified drill press that can be used for milling.
There is nothing wrong with a mill drill for what it is, and I am not bashing them. If that is the machine you want, buy it. I am sure it will be capable of doing good work.
If you ask which machine is better, the answer is the knee mill.
If you do not have the room for a Bridgeport, the smaller knee mills are still better machines than mill drills.

DeereGuy
12-09-2003, 02:50 PM
Thanks SCH, that is what I am referring to as a RF45 or a RF45 clone.


<font face="Verdana, Arial" size="2">Originally posted by sch:
Have you looked at the Grizzly G 0519, not
a knee mill but a dovetail drill mill with
a claimed 18" vertical clearance. Has a
"tapping" mode though it is not entirely
clear what this amounts to. Also has a
3phase motor so a VFD would be essential for
most of us, but this seems a clear benefit.
Priced about $1500, and at 6-700#, easy to
move. This machine appeared on the RongFu
web site about 3yrs ago. Steve</font>

DeereGuy
12-09-2003, 02:53 PM
Acutally, I was hoping to find someone that had actuall hands on experience with both and would be able to directly tell me from experience rather than hearsay what would be the benefits/drawbacks to both. I do appreciate all the feedback regardless if its opinion or experience.

Thanks All


<font face="Verdana, Arial" size="2">Originally posted by JCHannum:
The knee mill is a true milling machine. The mill drill, regardless of upgrades is a glorified drill press that can be used for milling.
There is nothing wrong with a mill drill for what it is, and I am not bashing them. If that is the machine you want, buy it. I am sure it will be capable of doing good work.
If you ask which machine is better, the answer is the knee mill.
If you do not have the room for a Bridgeport, the smaller knee mills are still better machines than mill drills. </font>

debequem
12-09-2003, 03:16 PM
I understand. I have the RF-31 and have 2 years of experience with that mill. My experience with the Bridgeport is long ago. However, I can cite some trade offs.

Besides the obvious (size, weight, and mechanical operation), the RF-31 has a potential for the head to shift laterally if too heavy a cut is made and your registration will change. The square column won't do that, but you can't rotate the head laterally to do special milling operations off of the mill table. That may not be an issue, but you don't have that option with the RF-45.

I found the Chinese bearings to be problematic in the RF-31 (just replaced mine after 2 years). I also have problems with the lead screws and the table ways on my Rong-Fu. I was not impressed with the quality. I was concerned that the RF-45 may not offer much improvement since I want to replace my 31. If you are buying a clone I would be concerned that the quality will be even worse. Given that the RF-45 gear head is much more complex, I would expect that the probability of incidents over time will be higher still. No data to support that.

You will need to get a spindle wrench (or make one) for the RF-45 since you don’t have a belt to grab or a brake to lock the spindle when you tighten the draw bar. I have heard of a few problems where the collet wasn’t tight on these mills and the end mill creeped out.

One large advantage of a heavier mill is stability when making tough cuts. The mass really is your friend. You get better finishes and save time by making deeper cuts. The RF-45 does have a tiny bit more mass, so it should help with rigidity, but I would expect that to be small. The 45 is larger, but only proportionally heavier. The true rigidity may not be a lot more, but got to be better than a round column. Then again, what would be worse, piano wire?

There are a number of larger knee mills out there, but you didn’t state your budget. Sounds like it is low. I also don’t really know your short and long term plans.

Since I was carefully considering the 45 as an upgrade because I couldn’t fit a full size mill. However, after reviewing all of the options I decided to modify my environment to accept the larger and heavier Bridgeport. I think my total cost will be the same as a Rong-Fu RF-45, but I expect to have a much better mill long term. That is why I am touting the BP solution.

Good luck, I hope you get something that works fo ryou.

Marv

DeereGuy
12-09-2003, 07:15 PM
Marv, great response and I appreciate the time you took to post it. Your thinking is pretty much along the lines that I have been fighting with. I am going to look this over a little closer this weekend when I go to Detroit.

Bob


<font face="Verdana, Arial" size="2">Originally posted by debequem:
I understand. I have the RF-31 and have 2 years of experience with that mill. My experience with the Bridgeport is long ago. However, I can cite some trade offs.

Besides the obvious (size, weight, and mechanical operation), the RF-31 has a potential for the head to shift laterally if too heavy a cut is made and your registration will change. The square column won't do that, but you can't rotate the head laterally to do special milling operations off of the mill table. That may not be an issue, but you don't have that option with the RF-45.

I found the Chinese bearings to be problematic in the RF-31 (just replaced mine after 2 years). I also have problems with the lead screws and the table ways on my Rong-Fu. I was not impressed with the quality. I was concerned that the RF-45 may not offer much improvement since I want to replace my 31. If you are buying a clone I would be concerned that the quality will be even worse. Given that the RF-45 gear head is much more complex, I would expect that the probability of incidents over time will be higher still. No data to support that.

You will need to get a spindle wrench (or make one) for the RF-45 since you don’t have a belt to grab or a brake to lock the spindle when you tighten the draw bar. I have heard of a few problems where the collet wasn’t tight on these mills and the end mill creeped out.

One large advantage of a heavier mill is stability when making tough cuts. The mass really is your friend. You get better finishes and save time by making deeper cuts. The RF-45 does have a tiny bit more mass, so it should help with rigidity, but I would expect that to be small. The 45 is larger, but only proportionally heavier. The true rigidity may not be a lot more, but got to be better than a round column. Then again, what would be worse, piano wire?

There are a number of larger knee mills out there, but you didn’t state your budget. Sounds like it is low. I also don’t really know your short and long term plans.

Since I was carefully considering the 45 as an upgrade because I couldn’t fit a full size mill. However, after reviewing all of the options I decided to modify my environment to accept the larger and heavier Bridgeport. I think my total cost will be the same as a Rong-Fu RF-45, but I expect to have a much better mill long term. That is why I am touting the BP solution.

Good luck, I hope you get something that works fo ryou.

Marv</font>

PeteM
12-09-2003, 08:03 PM
Bob, Since it's about 100:1 in favor of a Bridgeport, I thought I'd lend a little support to the new iron underdog.

I don't own the Taiwan-made RF45, but have a friend who does and is happy with it. As you know, the problem with a mill drill isn't so much the milling, as the loss of location, and the lack of such amenities as a tilting head, quick speed changes, etc. The RF45 solves many of these problems.

Certainly, a full size Bridgeport in great condition will beat it, but this isn't an option for many. It's more than twice the weight and, unless you're lucky, usually more costly or priced about the same and beat up. Given what's happening to US job shops, now is a good time to get "lucky," but that's another thread.

The RF45 has more power than many early Bridgeports and a comparable working envelope to the short table Bridgeport. Compared to a 2/3 size machine like a Clausing or Millrite it has much more cross travel. That's important for things like bolt circles.

At the risk of heresy, I don't think the 100 year old practice of raising the table with a massive knee rather than lowering the head on a dovetail is sacrosanct. Lots of machine makers have found ways to make lighter weight machine tools, without sacrificing throughput or cut quality. The analogy isn't perfect, but a couple decades ago woodworkers were saying that they needed 1200 pound planers to surface wood without chatter and snipe. I happen to have one of those beasts, but must now ackowledge that 120 pound lightweight (wood) planers are doing a pretty nice job. I'd suggest that the RF45 is kind of like the first lightweight planer -- the basic design is a decent idea. By abandoning the massive lower support and knee it should be able to make a rigid machine with less weight and lower cost than a comparable Bridgeport type mill.

Of course, if you find that mint Bridgeport for $1395, grab it quick.

Thrud
12-10-2003, 12:47 AM
Considering the cost difference between a half assed good knee mill and a RF45 - get teh RF45. It is a heavy well made machine for its price. The ones sold here are nice machines. I would consider a VFD and 3phase motor for it. They are available with NT30 spindles instead of R8 - if it was me I would get an NT30. It is a nice size for the size restricted shop and still a serious chunk of iron. If I had the room, I would have one myself.

That being said, if you are patient you can get good deals on older BPs that need some TLC and paint.

DeereGuy
12-14-2003, 09:05 PM
Thrud and all, I picked up my RF45 knock off at WTtools saturday morning. Once I got it bolted to down its new home I checked the tram. Luckily I had no measureable differences with idicator which is on good to .0005. I let it run in all the gears except for high for about 4 hours with no load. Once everything settled in the gears noise quieted down to a subtle whiring. Initial checking of the repeatability of the head after raising and lower was great. Again no measureable difference. So far it seems to be a very sold smooth machine and I look forward to using it. I also lowered the spindle enough so I could put the indicator of in from the front and the side then pushed up the head in the front and then on the side. No deflection could be measured. I was very pleased with this because the RF31 had nearly .002 deflection with just a gently push upwards on the head from the front. The friend that helped me check this out before purchase has an older index and has just under .0005 deflection with the same test. Course his is almost 60 years old. It's a very nice smooth machine also.

Have a good evening all
Bob

torker
12-16-2003, 07:52 AM
Bob... can you keep us posted after you use your new mill. I'm seriously thinking of buying one of these machines also and am very interested in how it works out for you. Thanks.

DeereGuy
12-16-2003, 09:55 AM
Torker sure, I will wait till I have had it awhile and really put it though some actual projects. Things always seem to crop up good and bad after you have used the machinery some.

mbensema
12-16-2003, 10:13 AM
Deerguy, have you thought of writing an article for HSM on the new mill? There was a thread recently about the lack of machinery reviews and this sounds like a great opportunity to write about your experiences. If you are not good at writing, I'm sure there is someone who could help you with it.

Mike

DeereGuy
12-16-2003, 01:30 PM
Actually I have helped do an article, just a critiqe actually after the writer for Farmshow Magazine had written it. This is a Feature article that FarmShow magazine did on the bucket I designed and built last Winter.

http://www.farmshow.com/issues/27/04/270401.asp

I am not sure what kind of time I am going to have but if HSM wants to do an article maybe they could start by sending me and outline and we could go from there.

Bob

lunkenheimer
12-16-2003, 02:04 PM
I have one of the RF-45 clones on the way; maybe we could do a two-sample review and co-author an article. It's not due until February, though :-(

DeereGuy
12-16-2003, 02:24 PM
Sure, Keep in touch. You anywhere around the Lansing Mi area?

Bob

BillH
12-16-2003, 02:50 PM
To me, I used to use features as the over riding factor in the machine I buy. Now however, since I picked up my southbend lathe, and compared it to my chinese one, the over riding factor to me is who made it.
Ofcourse im still just a newbie at machining, but there is a huge difference between American made and Chinese made that I can see. I am now hard pressed to buy a new machine when I can find a used one locally that is better quality and much cheaper. Sure it may need new paint, or a few parts.
I see exceptions though to mills. My southbend lathe weighs 250lbs and is easy to move, where as your not going to find a used American made mill that weighs less than 1000lbs I don't think.

JCHannum
12-16-2003, 02:58 PM
I am curious. There are two mentions of RF knockoff or RF clone.
I thought that Rong Fu was a manufacturer of economically priced machine tools. Is it my understanding that these machines are lower priced knockoffs of an already inexpensive machine?

Joel
12-16-2003, 03:35 PM
JC, I believe the Rong Fu machines are basically the same. The quality control seems to be better, so the fit, finish, and tolerances are improved over the less expensive import machines.

Thrud
12-17-2003, 12:31 AM
It is important to note that all of these similar machines may in fact be made by Rong Fu itself. The difference being what level of quality the buyer ("Name Brand") is willing to pay for. I learned this in a article written in Fine Woodworking a very long time ago when they talked to Delta and visited the overseas plants that made their equipment. You pays your maney and gets what you pay for.

xxdarby
12-22-2003, 10:42 PM
I have been following with great interest as to your purchase of the rf45 and the various responses from the crew! I too have been looking for a mill/drill and came across the 20" square column mill/drill from enco.Did you happen to compare the two?
I agree with an earlier comment whereas a piece of metal in the vise dosent know if it is taking a ride up on the knee or if the head is comming down to eat it!

DeereGuy
12-23-2003, 07:27 AM
Actually I did look at what Enco had to offer. After looking first hand at the one WTtools had to offer and listening to it run on the show room floor I was pretty happy with what they had. I bought my new WTtool 13 x 40 gearhead lathe and this at the same time and they made me a really great price on everything. I saved on shipping because I am close to Detroit. I brought the lathe home one weekend and went back two weekends later to pick up the mill. I am going back this Saturday to pick up my table feed and some other goodies and they made me a special price on the table feed. After having this mill for a while I think I was better off getting this over one of the smaller knee mills. I have a larger table, more spindle to table clearance and I think this mill seems to be more rigid. It was mentioned that perhaps I might write a review on this mill and I am making notes to do that someday. I can tell you that Wttools has been great to work with. There have been some minor things I needed taken care of and they were right there to take care of me.

Happy Holidays all
Bob

[This message has been edited by deere_x475guy (edited 12-23-2003).]

mendoje
12-23-2003, 08:53 AM
The RF45 and even the tabletop HF mini-mill are small versions of bed mills, like these:

http://www.servoproductsco.com/html/sam_6_cnc.html

http://www.clausing-industrial.com/Products/CNC/Atlas/cnc_atlas4and6bedmillhome.htm

http://www.cncauto.com/prod04.htm

Jeff