Thread: Metex Opti BF20L Mills?

BF20 aka G0704 are generally regarded as having a better column, which is a weak point on the X3 apparently.

Originally Posted by wm460

I was looking at these mills and wondering if any one has any experience with them, good or bad?

http://www.ebay.com.au/itm/Metex-Opt...item3f275603d6

They appear to be the equivalent to the Seig Super X3 is this correct?

Which is the better mill?

Both the Sieg X3 and the and the Optimum BF20 are rectangular column desktop mill/drills made in China in the 1.5 to 2K$ price class. That is where the similarities end. The X3 is much heavier, has no swivel head, MT3 or R8 spindle instead of MT2, and the whole design is different. The X3 column is indeed open at the rear, but IMO the weight difference alone would more than make up for this if compared to the BF20.

I do not think someone can easily tell you which one is the better mill. It depends what you want to do, how you personally like to do it, and which features you particularly value over others. If you can, go and have a look at both before deciding.

Hi Mark, one of the first things that I would do is to check what the gears are made from, as a lot of the smaller units run plastic gears for the hi/low reduction, a replacement set for the X2 is around the $55.00 plus postage, which gets expensive, if you are a bit heavy handed. DAMHIKT as I've gone through about 6 sets
Kryn

Originally Posted by wm460

I was looking at these mills and wondering if any one has any experience with them, good or bad?

http://www.ebay.com.au/itm/Metex-Opt...item3f275603d6

They appear to be the equivalent to the Seig Super X3 is this correct?

Which is the better mill?

That is the same mill as mine ! Just a different brand name and green in color.
I ended up making new steel gears for mine after a jam ripped the teeth off the plastic gears. Apart from the usual crap tapered gibs the only problem I have at the moment is the front of the table seems to be about 3 thou higher than the back. Mine is in bits at the moment while I find out what has to be done to get everything square.

Almost forgot I'm on my second motor. The first one just started smoking. The supplier replaced it FOC. I've recently repaired the second motor after the brushes failed and damaged the wiring inside causing a short to the case. I made new brush holders and fitted new brushes. Its back in service now.

Originally Posted by cba_melbourne

Both the Sieg X3 and the and the Optimum BF20 are rectangular column desktop mill/drills made in China in the 1.5 to 2K$ price class. That is where the similarities end. The X3 is much heavier, has no swivel head, MT3 or R8 spindle instead of MT2, and the whole design is different. The X3 column is indeed open at the rear, but IMO the weight difference alone would more than make up for this if compared to the BF20.

I do not think someone can easily tell you which one is the better mill. It depends what you want to do, how you personally like to do it, and which features you particularly value over others. If you can, go and have a look at both before deciding.

Mine is MT3, but you can have R8 if you want it.

Originally Posted by BaronJ

That is the same mill as mine ! Just a different brand name and green in color.
I ended up making new steel gears for mine after a jam ripped the teeth off the plastic gears. Apart from the usual crap tapered gibs the only problem I have at the moment is the front of the table seems to be about 3 thou higher than the back. Mine is in bits at the moment while I find out what has to be done to get everything square.

Almost forgot I'm on my second motor. The first one just started smoking. The supplier replaced it FOC. I've recently repaired the second motor after the brushes failed and damaged the wiring inside causing a short to the case. I made new brush holders and fitted new brushes. Its back in service now.
[/FONT][/COLOR]

Like with many other Chinese machine tools, there are sometimes big quality differences between the genuine thing and its clones. We recently had a thread about a Tormach clone, sold in Australia as a Titan where the dealer said it was made in the same Tormach factory, but the castings had extreme and unacceptable defects. I would be careful comparing a Tormach or a Sieg or an Optimum with identical looking clone machine tools sold under other than the genuine brand name. They may not come out of the same factory, or/and they may have been made using main components rejected by the original factory. Not saying its always like that, but it may, especially if the price difference seems almost too good to be true.

That said, like all low cost Chinese made machine tools, the genuine Optimum BF20 is not free of problems. I think this mill sells a lot in Germany, so much info about it is in German language (Optimum being a German company, manufacturing their cheaper range in China). The plastic gears and the motor are often mentioned in German machining groups.

There are aftermarket steel gears for the Optimum BF20, and these should also fit the Optimum BF20 clones that are out there.
- See here a video: hhttps://www.youtube.com/watch?v=v_b0-p6V
- You can buy the aftermarket steel gears on Amazon for 74 Euro: http://www.amazon.de/Ersatz-Zahnrad-.../dp/B00OLVOYQA. The seller claims they will also fit many BF20 clones such as the Bernardo KF 25 D, Holzmann BF 20 D, Elmag MFB 15, Epple BFM 20, Swisstec ST 25.

There are also several conversions on the net from the DC motor to 3-phase motor/VFD for the Optimum BF20. Plenty of examples and pictures if you google for "Optimum BF20 motor" and "Optimum BF20 getriebe".

Thanks for your replies every one.

The X3 column Being open at the rear, could covered by steel plate to rectify this problem?

The gears, every thing I have been reading on the internet says that converting the mill too belt drive is the better way to go, is this correct?

I presume that the gears in the mills are made from plastic because it is cheaper to manufacture and are quieter when they are running.
This bloke is making conversion kits for Sieg mill, he hasn't got X3 in stock atm.

http://www.ebay.co.uk/itm/Sieg-X2-mi...item3cf426f1c3

Optimum BF20L from Redfox Machinery is net weight 103kg
Optimum BF20LV from H&F is net weight 163kg
Seig X3 from H&F 190kg

H&F BF20LV Is available in 3MT

ATM H&F have a sale on the Optimum BF20LV is $1,529.00 and the Seig X3 is $2,189.00

Is the Seig worth $660.00 more?

Baron J sounds like you have had a run of bad luck, is the table a major problem to fix?

Is it worth getting the stand to suit or not is it possible to put these on wheels like you get for wood working machinery? Interesting H&F delivery charge estimator, both machines cost the same also no difference in price whether here or 500km south.

BTW Kryn, the wife doesn't know any thing about this, if you see some one bandaged up like a mummy if a couple weeks time you know she disapproved.

Hi Mark, when you come down, I'll give you a copy of the details to convert to belt drive in case you are interested later on, that is if you'll be able to drive. The reason people go for belt drive, is that it is quieter, even though the gears are plastic, the system is very noisy.
Regards
Kryn

> The X3 column Being open at the rear, could covered by steel plate to rectify this problem?

But... who says this that this is a problem at all? I have had my X3 for 11 years now and never felt it lacking column rigidity. Of course, the whole column is enclosed sides, rear and top by a steel housing. I actually thought the open column is a good thing, easy to access the innards of the column. I even put the whole Z scale inside the column.

I think that the open column is a problem with the much smaller and lighter Sieg minimill. That does not automatically make it a problem for the X3.


> The gears, every thing I have been reading on the internet says that converting the mill too belt drive is the better way to go, is this correct?

I spent a lot of time improving the X3 gearbox. Its all metal gears, but not precision ground nor hardened, and very noisy. After about 6 years I gave up and upgraded it to belt drive and VFD. Muuuch quieter, much smoother, yes its the best way to go. See here how I did it if interested:
http://www.homemodelenginemachinist.com/downloads/files/X3_VFD_Part1_version2.pdf
and
http://www.homemodelenginemachinist....2_version2.pdf



> I presume that the gears in the mills are made from plastic because it is cheaper to manufacture and are quieter when they are running.

Correct. In the past that was different, good quality hobbymills used precision ground steel gears meshing with "plastic" gears made from cotton reinforced phenolic resin (Tufnol and many other trade names). But such top quality plastic gears actually cost more than steel gears, the material itself is quite expensive.


> This bloke is making conversion kits for Sieg mill, he hasn't got X3 in stock atm.
> http://www.ebay.co.uk/itm/Sieg-X2-mini-mill-belt-drive-conversion-kit-/261794230723?pt=LH_DefaultDomain_0&hash=item3cf426f1c3

I did not know that somebody now makes a commercial belt drive kit for the X3. Are you sure?


> Optimum BF20L from Redfox Machinery is net weight 103kg
> Optimum BF20LV from H&F is net weight 163kg
> Seig X3 from H&F 190kg
> H&F BF20LV Is available in 3MT
> ATM H&F have a sale on the Optimum BF20LV is $1,529.00 and the Seig X3 is $2,189.00

You are confusing the Sieg x3 with the Sieg SuperX3. The X3 is $1750 at H&F, the SX3 is $2150 at H$F, both plus GST.


> Is the Seig worth $660.00 more?

The Sieg X3 is 178kg and is IMHO good value for $1750. The Sieg SX3 has some extra features and is IMO good value too.
The Optimum BF20LV is on special at machineryhouse right now, $1390 plus gst, and I think is good value too. You choose the features you want and pick any.

But be warned, they all are low cost Chinese hobbymills, and they all WILL need some tender loving care to become good.

Hello Mark,

My mill has a solid column with an opening at the front for the head to move up & down the dovetails. It weighs 170Kg and has an extra long bed.
The gears that Cba links to are the plastic ones. There is a thread somewhere where I did a wip of the making of the new steel gears. I've not yet found any commercial manufacturer of a set of steel gears. I purchased four individual gears from HPC and machined them to suit.

I discovered that when I bought the mill, the spindle was quite tight to rotate. I initially thought that it was because it was new it just needed running in. One thing that I did notice immediately was when the mill was running, there was a regular, "thump, thump". After the gears failed, I discovered that the plastic gear was bored at a slight angle, making the gear eccentric. My conclusion is that this was making the spindle tight to turn and causing the thumping sound.

I did give very careful consideration to trying to do a belt conversion. But due to the way that the mill is constructed, it would be very difficult if not impossible to do.

When I bought my mill, I had the choice of MT3 or R8. Either works for me. Actually I had quite a bit of R8 tooling which I foolishly sold, but that's another story.

Noise ! Everyone says that a belt conversion is good because it reduces the noise generated. The mill is no more noisy than the lathe ! I have noticed that the spindle runs on a lot longer than it originally did, but that is no surprise considering the original gear problem. The finish on the work is better and I can push the mill quite hard. 0.5 mm on a 70 mm fly cutter across 35 mm surface in mild steel or a full mm in aluminium, is quite respectable.

As far as the table issues are concerned, I purchased a new 90 mm wide precision milling vice. This was because I found that I couldn't square up a piece of stock in my old "Record 404" vice. Then I found that I couldn't do it in the new vice. I always found that I got a few thou of taper, both across and down the length of the work.

At the moment the mill table is with a local engineering company that has offered to have a look at it for me. I will be going to see them on Monday to see what they have found. More about that later.

Hope this info helps.

> The gears that Cba links to are the plastic ones. There is a thread somewhere where I did a wip of the making of the new steel gears. I've not yet found any commercial manufacturer of a set of steel gears. I purchased four individual gears from HPC and machined them to suit.

No, both the links that I gave were for real genuine STEEL gears (made of C45 steel) to replace the BF20 plastic gears. Trust me, German is my mother tongue. Check it out:

http://www.amazon.de/Ersatz-Zahnrad-.../dp/B00OLVOYQA

If you already replaced several times the plastic gears, you should probably consider upgrading to these steel gears next time.

PS: this seller does not post to Australia, but probably to other EU countries

Originally Posted by cba_melbourne

> The gears that Cba links to are the plastic ones. There is a thread somewhere where I did a wip of the making of the new steel gears. I've not yet found any commercial manufacturer of a set of steel gears. I purchased four individual gears from HPC and machined them to suit.

No, both the links that I gave were for real genuine STEEL gears (made of C45 steel) to replace the BF20 plastic gears. Trust me, German is my mother tongue. Check it out:

http://www.amazon.de/Ersatz-Zahnrad-.../dp/B00OLVOYQA

If you already replaced several times the plastic gears, you should probably consider upgrading to these steel gears next time.

PS: this seller does not post to Australia, but probably to other EU countries

Apologies. My German is next to non existent. I only recognised the word "Plastik". Thanks for the link and correction.

I got this email from General tools In Adelaide a H&F reseller, it may be of interest to you.


Hi Mark
Thank you for your enquiry. The Optimum range of machines has only just been released (as a replacement for the Sieg range), and while we have received a BF-16A into our showroom (which looks like a very good build), we have not yet seen a BF-20LV in the flesh. I have checked stock around the country, and there are now no Sieg Super X3's left (there are a couple of standard X3's in Sydney and one on display in Melbourne).
The X3's are very nice machines. Well put together for precise work but not heavy duty as they only have a 3/4HP motor. The BF-20LV seems like it would be a bit more robust with a 1.13HP motor (Face Milling Capacities are X3 50mm and BF-20LV 63mm). The X3 has a fixed head, while the BF-20LV tilts 90 degrees left and right, which is a must for milling in my opinion. Travels are similar, though the X3 has a bit more vertical. Both machines are, however, for light work like model engineering. If you are looking for a "workshop" machine you should consider the HM46 or HM-48.
Best regards
--
Darren Redman
Sales & Marketing Manager

I have both mills. A Sieg X3 and the Optimum BF20L.

I've actually never used the X3 and its still sitting there, I bought it with other stuff in a sale.

The BF20 I have has been a nightmare. Well the issue more lies in the seller who refused to warranty the item (Ausino Engineering Supplies in Coburg). Mine has a terminal defect in that the Z column dovetail that the head rides on is not parallel. ie. it's narrower in the middle than at either end (both sides dish in about 10 though). As I result I can not tram the head as head position varies in different positions along the dovetail. If you adjust the gib strip the head is tight/binds at the top/bottom of travel but yet it sloppy in the middle. If you lock the gib strips it will kick the head one way or the other depending where you are. Forget about being able to mill anything flat. If you put a drill bit in, given the length of the tool quite often your hole would be 1mm+ out of vertical alignment.

So mine has just sat there. Done a few basic jobs where precision didn't matter but its been too stressful for me to deal with and I nearly feel ill when I see it sitting in the shed. Its fantastic that Hare and Forbes stock them now as they might at least back them up. The good news for me is that I just may be lucky enough to try and chance my luck with possibly buying a replacement vertical column from Hare and Forbes and changing the bits over. Again that's a crap shoot but at the moment I wouldn't even sell mine to anyone. But it could be throwing good money after bad.*

I do like the design of the mill in the whole, more so than the X3 (which I have still yet to use. X3 has MT3 tooling, my BF20 has MT2). I tooled up for the MT2. BTW I'd get it in R8 but it wasn't an option for me. General reports are that people are happy with them and they are a better mill than the X3.

I'll get back to doing something about it eventually but I just wish I'd never bought the thing from that seller. He screwed me right and proper and still sells on Ebay and Gumtree.

*Looking at H&F pricing, depending in how much the column casting alone might cost me I'd probably nearly be better off just buying the whole lathe milling attachment for ~$700 and bolting the whole unit onto my current base/table.