RongFu RF 25 Drill/Mill

[gus]

With router down and WiFi dead for 2 days,I have time to window shop for Mill.
Apple to Apple comparison between a Sieg and Rongu RF 25, I am about to pick the robust RongFu over the Sieg.
Fotos are attached for evaluation. Your 2 cents worth is seeked to guide my decision to buy a robust vee belt drive Rongfu over the Elecronic Variable Speed Sieg. I mostly use 10mm and 12 mm EndMills. With the Rongfu ,I may use the 12------19 mm mills. I am a vee belt drive man for spindle speed change. Currently with the Sakai Mini Mill, by jobs size and work speed is severely hampered .
With the Rongfu RF25, I will be ambitious and going for the Howell V-4 Engine build.

 

[Gordon]

I had a similar round column Enco mill and one problem is that the spindle stroke (4"?) is rather short and once you move it you loose all orientation. This becomes a problem when you must change tooling even on a single hole. For instance spotting with a center drill and then drilling with a 4" long drill. Once you move the head up in the Z axis the X and Y are off.

 

[10K Pete]

I've spent a fair amount of time working with round column mill-drills
and I don't like 'em. As Gordon said, once you try to move the head you
lose vertical alignment.

For me it's a no-brainer: Get the square column machine!!

Pete

 

[ThomasSK]

Gus:
I have the round collumn RongFu machine, and I find 3 major problems:

• Y axis backlash difficult to compensate.
• Round colloumn looses orientation.
• Lack of low speed makes it hard to do gear cutting.

If you get one, make sure to carefully scrape off all paint on the bottom of the collumn, or the tramming of the mill will be difficult.
Also plan on tooling, that's the expencive part.

I think you should not be too afraid of the direct DC drive used in the Sieg machines. Electricity has the benefit of full momentum from 0.
Eventualy I plan on replacing the RF with a Sieg SX4.

 

[fcheslop]

Iv owned and abused a Rf25 since 1984 and the only parts changed are two sets of quill bearing and one set of feed screw nuts
Its never been very accurate and as mentioned the loss of location when raising the head is a pain but for the money £320 at the time its given very good service although now just about worn out and a crack developing around the lower locking bolt she is heading for the scrap yard once I find a replacement but what to replace it with Iv no idea
cheers

 

[ShopShoe]

Gus,

The Seig is not only square column, but dovetail with gib you can adjust. I have the Grizzly version of the X3 and I glad I chose it over a comparably-priced round-column machine (which, according to the specs, had more horsepower.) In my many learning exercises (screw-ups) I have managed to cause the controls to stop for safety, but the controller has survived for over five years at this point with no problems. Of course, I think I can get parts here in the USA and I do not know how hard it would be for you to get parts.

By the way, I love variable speed machines because I can adjust them on the fly. I also like forward-and-reverse. My machine is not sold as having a tapping feature, but I have done a fair amount of power tapping with the variable speed and spiral-flute taps. Drilling and tapping dozens of holes for a tooling plate was much easier than if I had to drill the holes, then hand tap each one. Similar jobs were ganging-up to make T-nuts and QCTP tool holders.

--ShopShoe

 

[gus]

Hi All.

Thanks for the valuable feed back. Will take another hard look at the Sieg and give it a fair evaluation. My worry is on the Variable Speed Drive performance and reliabilty. If I could buy the Sieg Mill from dealers comparable to ArcEuro etc, I would get a mill with best q.c. .The current Sieg importer worries me on backup with the Variable Speed Drive. As for precision drilling spot on the cross hair manually by scribing, center popping, spot drilling etc,my present skill is up to mark. Have survived 10 years with the Japanese Sakai mini will with 15mm quill feed. The Rongfu RF 25 gives me a quill feed of 100mm which will enough for the nearest future of 3---5 years. Gus is now 73 and hopefully by 78 ,my eyesight and heath remains good. The Spot Drilling and moving the mill head up to put longer tooling is another eye opener. The excessive weight of the Rongful Mill worries me on the floor loading compared to the Sieg Mill. Will do a 2 column yes/no review of both mills. Will be fun.Looks like it will be the Sieg. Would be great not losing the X and Y with Sieg. I did get around slyly with rather limited Sakai Mini Mill and stretched it beyond its capacity with nail biting milling jobs.

 

[driller1432]

Square column Square column I had the round column machine and it was a real pain as everyone else has said when you move up and down the column it swivels side to side and you lose orientation. The square column will be so much quieter and variable speed ----you will be much happier with the square column--- a real time saver.
Steve

 

[Niels Abildgaard]

Hello Gus
My 113 kg machine is this:

https://www.hbm-machines.com/produc...etaalfreesmachinesssub/hbm-bf-25-freesmachine

Do not wory about the variable speed.
It is a gift from heaven
It is put directly on the table plate over my washing machine with 2 M6 bolts.
It has just made the grinding jig shown for 2 times 2 mm carbide sticks that need a 85 degree corner.
Accuracy and silence is astonishing.
If the electronic go bust I put a 3 phase VFD on and is even more silent.

Better resolution
http://i.imgur.com/I0Cvetp.jpg
http://i.imgur.com/BxIejck.jpg

 

[Blogwitch]

Gus,

I survived for many years, and only just, using an RF mill drill.

It did everything I asked of it, but there was a lot I couldn't ask it to do because of the round column. There are mods you can do to them, but the column mod, I have yet to see an easy one done.

These machines are around 40 years old now, and have been long in the tooth ever since they were made as all they did was to stick a stronger quill on a drilling machine..

Get something with a square column and don't go through the suffering a lot of us have.


John

 

[grapegro]

Hi Gus,
I was guided by a highly qualified machinist when choosing my mill I bought an Optimum Bl 17, all movements are dovetailed and adjustable. Gear driven, variable speed and German design. Mine was made in Hong Kong or Taiwan, I fitted a mini DRO kit from Delos and ended up with a good quality accurate machine for well under $2000 Australian
Norm

 

[gus]

Hi Gus,
I was guided by a highly qualified machinist when choosing my mill I bought an Optimum Bl 17, all movements are dovetailed and adjustable. Gear driven, variable speed and German design. Mine was made in Hong Kong or Taiwan, I fitted a mini DRO kit from Delos and ended up with a good quality accurate machine for well under $2000 Australian
Norm

Hi Norm,

Please give me a foto shot of Optimum.

 

[gus]

Gus,

I survived for many years, and only just, using an RF mill drill.

It did everything I asked of it, but there was a lot I couldn't ask it to do because of the round column. There are mods you can do to them, but the column mod, I have yet to see an easy one done.

These machines are around 40 years old now, and have been long in the tooth ever since they were made as all they did was to stick a stronger quill on a drilling machine..

Get something with a square column and don't go through the suffering a lot of us have.


John

Good Advice. The Sakai Mini Mill too had a round column. There were some jobs which I had to do it other way which took long time. Had I gone into HMEM in 2004 before buying same mill,I too would have bought a Sieg or eqv. The RongFu RF 25 is a bit on the heavy side for our balcony. Will take another hard look at the Sieg Mill.

 

[bazmak]

Hi Gus I have just watched the 3 part review on utube of the Sieg sx 2.7
with tapping mode I was very impressed.I have the sx2 and I am very happy
Fixed sq column and variable speed very,very important.The sx2.7 also has tapered gibb to vertical.There are a few minor bad points but overall it
looks good.As I said I am very happy with the smaller Sx2 but if I upgrade I would go for the Sx2.7.My main problem would be if something went wrong with the electronics as did with the lathe then it would be the end for me.So far after a couple of years no problems.PLEASE LOOK UP THE UTUBE REVIEW
its in 3 parts just google .The z axis has digital readout which is good
I fitted a vernier to mine and would not be without it. Regards Barry

 

[gus]

Hi Gus I have just watched the 3 part review on utube of the Sieg sx 2.7
with tapping mode I was very impressed.I have the sx2 and I am very happy
Fixed sq column and variable speed very,very important.The sx2.7 also has tapered gibb to vertical.There are a few minor bad points but overall it
looks good.As I said I am very happy with the smaller Sx2 but if I upgrade I would go for the Sx2.7.My main problem would be if something went wrong with the electronics as did with the lathe then it would be the end for me.So far after a couple of years no problems.PLEASE LOOK UP THE UTUBE REVIEW
its in 3 parts just google .The z axis has digital readout which is good
I fitted a vernier to mine and would not be without it. Regards Barry

Hi Barry,

Your timely and good advice has swung me away from buying the Rongfu RF25 which has one disadvantage when the milling head is raised on the round column the X&Y get compromised. The truth was really the RongFu sells at S$1800 list and the Sieg 2.7 at S$2400 list. Cheapskate Gus was going for the lower price but after looking at ArcEuro's Sieg Super 3 which sells at S$2437 ex-UK. The local importer is willing to give me best deal.Feed back from the vets like John aka Blogwitch was very useful and postive. I have endured for last 10 years with the round column Sakai Mini Mill and its about time I switch. Most likely will buy Sieg 2.7 after the Melbourne trip to see my 2 grandkids at Glenhuntly and Paul Swift at Mount Martha. Where is Barry located?? See you.

 

[bazmak]

Hi Gus,im in Adelaide if your ever over this way call and see me.
Did you look at the utube review ??.I have just made a super loose jaw vice
that works really well.I mentioned your name but its a good early job for your new Mill.Will you go for the tapping model ?? If mine ever goes on the blink
I will upgrade to the 2.7 as I did with lathe.

 

[gus]

Hi Gus,im in Adelaide if your ever over this way call and see me.
Did you look at the utube review ??.I have just made a super loose jaw vice
that works really well.I mentioned your name but its a good early job for your new Mill.Will you go for the tapping model ?? If mine ever goes on the blink
I will upgrade to the 2.7 as I did with lathe.

Hi Barry,

Some years back when I was an employed high flier by Ingersoll-Rand,I took my wife to Adelaide. Very good Aussie Food and HongKong Chinese Food too.
Loved their baked oysters.

 

[bazmak]

I will stick with fish and chips,it was a very brave or hungry man who ate the first oyster

 

[grapegro]

Hello Gus,
Not sure what you are after, whether it is machine details or a picture of my fitted out mill. For details of Optimum milling machines, google Optimum BL17 mill and you will get their complete range.
Norm

 

[Niels Abildgaard]

Hello Gus,
Not sure what you are after, whether it is machine details or a picture of my fitted out mill. For details of Optimum milling machines, google Optimum BL17 mill and you will get their complete range.
Norm

Hello Gus



Google BF instead of BL

By the way the Optimum BF 20 is two times as expensive and less performant than my HBM BF25