BF20LV Draw bar thread confusion

[marvin_schwartz]

I'm just about to buy my first mill and just before I placed the order I got totally confused.

The mill in question is the BF20LV.
The Hare and Forbes web site shows the spindle as MT3 M10.
But I can not find any MT3's with a M10 thread. They all seem to be M12.
Given this is a 9x20 very popular late I wonder why I can't find an M10 shank.

The next thing that confuses me is under accessories in the the manual it shows all the collet chucks as MT2 M10. Which I can find everywhere . But how did an MT3 taper suddenly become an MT2?

So is it an MT2 or MT3?
What's the thread? M10 or M12?

What am I missing?

 

[bazmak]

If you can go to R8 rather than MT its a much better fitting

 

[marvin_schwartz]

I don;t think this model can do that

 

[miglincit]

So is it an MT2 or MT3?
What's the thread? M10 or M12?

Mine has MT2 and M10 of course.

Thomas

 

[deeferdog]

Hi Marvin, I have the mill in question and I purchased it from Hare and Forbes a couple of years ago. Unless they have changed the spindle is MT3 and the draw bar 1/2" Whitworth. All my tooling was M12 so in desperation I ran a 12mm die over the thread and promised myself that I would make a new draw bar ASAP. I will one day. The machine, by the way, is excellent. Cheers, Peter.

 

[marvin_schwartz]

awesome.

thanks

 

[marvin_schwartz]

Hey Peter,

I assume you are running collets. Are you using a a collet holder with an MT3 or MT2?

The user manual on the H&F site shows the collet accessories as MT2 which sound wrong to me.

Any recommendation on collet size I hear ER32 are problematic in clearing chips when you right down the bottom of a hole. I was thinking ER20 or ER25. Any thoughts.

PS.
I think I've decided to do what you did and run an M12 over the draw bar and maybe make a new draw bar with M12 if I stuff it up. Could be a good first project for the lathe.

 

[grapegro]

Hello Marvin, I have a BL 17 mill which is a very good unit. The original makers design quoted an MT 2shaft, but the company I bought it from supplied an MT3 shaft which I needed to be able to use tools I already had. Problem was a 1/2 inch drawbar. The price of tools for this drawbar was far too high so made a 12 mm bar in my lathe and all is well . This the way I would advise by experience, Norm

 

[deeferdog]

Hi Marvin,

I use ER32 collets in an ER32 collet chuck with a MT3. The MT3 is the spindle size of the BF20LV that I own. I also have a set of ER11 collets with an ER11 collet chuck. This also has a MT3. ER11 collets range from 1.0mm to 7mm in 0.5mm increments and are especially good for holding small size end mills as the chuck is quite small and does not get in the way like the ER32 chuck does. I like ER32 as it goes all the way up to 20mm and I use this size for a lot of my tooling. I have posted some pics, you can see the difference in size between the ER11 and 32 collets. My face cutter is held in a 20mm straight shank arbor so I hold that with the 20mm ER 32 collet, likewise thw general purpose tool holder that I made.
I looked at the latest spec sheet on the BF20LV mill from H & F and they state the spindle size is MT3. https://www.machineryhouse.com.au/M650 I understand your confusion, some of the sales people at H & F are not as well informed about their products as they could be, I also sometimes get the impression that the hobbyist is a bit of a nuisance to their main business of selling "real" machines. Apart from that I have found them to be an excellent company to deal with and they have solidly backed their products when needed. I woulden't buy from anyone else.
Having said that, the mill is excellent and allows for extensive modifications. There are numerous sites about the machine, generally it is referred to as the Grizzly GO704 as this is the name it is sold under in the US. If you Google that you will find lots of information. Feel free to contact me if I can help further, Cheers, Peter.

 

[Wizard69]

Hey Peter,

I assume you are running collets. Are you using a a collet holder with an MT3 or MT2?

The user manual on the H&F site shows the collet accessories as MT2 which sound wrong to me.

Any recommendation on collet size I hear ER32 are problematic in clearing chips when you right down the bottom of a hole. I was thinking ER20 or ER25. Any thoughts.

PS.
I think I've decided to do what you did and run an M12 over the draw bar and maybe make a new draw bar with M12 if I stuff it up. Could be a good first project for the lathe.

If you haven't purchased the machine I'd suggest going R8, giving you far more flexibility. Here in the USA decent MT tooling and collets are actually hard to find compared to R8 taper. Now a lot of R8 tooling was originally designed for Bridgeport style machines but is still applicable on a small mill.

With R8 you get the ability to run end mills in R8 collets directly or use a host of different collet extensions.

I'm not sure what the demand in your country is for MT shanks in a mill, but such is not even salable over here. In fact some vendors have tried to move such hardware eventually dropping the machines for R8 variants.

 

[Wizard69]

Hi Marvin,

.......
Having said that, the mill is excellent and allows for extensive modifications. There are numerous sites about the machine, generally it is referred to as the Grizzly GO704 as this is the name it is sold under in the US. If you Google that you will find lots of information. Feel free to contact me if I can help further, Cheers, Peter.

In the USA the G0704 is sold with an R8 taper. I still haven't figured out is the usage of MT shanks in the UK is due too demand or companies like H&F forcing the taper on users. I just find it interesting that the same basic machine comes with entirely different spindle tapers on the other side of the pond.

 

[marvin_schwartz]

Thank Peter,

You have confirmed what I thought.
If you look at the manual for the BF20 on the H&F site, they call out MT2 for all the collet accessories for that machine, which you have now confirmed is rubbish.

I'll go with MT3 tooling.
I'll definitely get the ER32 as I already have a number of bit's that have 20 mm shanks.

Now the question is do I go ER20 or ER11? I never considered the ER11 but if it works well it could be a great idea as I'm planning to get a cheap CNC engraver for plastic and PCB boards, which would take an ER11.

Thanks again


Hey Wiz,

I agree the R8 looks like a better arrangement, but this mill doesn't come with an R8 option and the nearest Sieg is around $500 more. Given everything here is metric the Bridgeport is not as prevalent as in the states. Also MT is easy to get as long as it's MT3 M12. So I'll start with MT3 fingers crossed.

Shame the mini mill 2nd hand market is non existent down here otherwise I would have gone down that path.

Once I get the gear I'll post some pictures and what I did to make the draw bar work.

 

[deeferdog]

Wiz, I'm not sure R8 gets a lot of traction in Oz. Morse taper still seems to be the preferred style for bench top mills, larger machines use NT. Morse taper collets are readily available, I have some myself but I do like the ER system. My lathe has a MT3 taper in the tailstock and a MT4 in the spindle so it sort of made sense to stick with this for me. All my large drills are either MT2 or three, thus I can use them in both machines. I have never used R8 so I can't say which is better, my advice to any hobbiest would be to stick to the system that is the most popular in the country you reside in, that way you are more likely to pick up old tooling at car boot sales that will fit your machine, particularly if you are a bit of an old scrounger like me!
Cheers, Peter.

 

[deeferdog]

Hey Marv, check out this mob,https://www.banggood.com/search/er-collets.html I find them good to deal with. Cheers, Peter

 

[bruedney]

Have al look at James' thread on threads here http://www.homemodelenginemachinist.com/showthread.php?t=26059&page=2

 

[marvin_schwartz]

Thanks that post was exactly what I need to do.
The cad diagram was great, that will save a bunch of measuring.

I have some nice stainless which should suit this job well.

So all I need is get the gear and make the bar.
After I practice a bit.

Still don't understand how anyone can put a product on the market that requires you to modify it before it's really usable. 12 inch WW really what sorta rubbish is that.

 

[Wizard69]

If R8 isn't available locally or just not popular I can see why you might want to go to MT. Around here Bridgeport's are everywhere, in the summer I see many sitting in garages if the garage door is open. ( don't have one though, madness) That extreme popularity in the past has lead to a lot of cheap R8 shank tooling both used and new.

Wiz, I'm not sure R8 gets a lot of traction in Oz. Morse taper still seems to be the preferred style for bench top mills, larger machines use NT. Morse taper collets are readily available, I have some myself but I do like the ER system.

The ER system is nice but you do end up buying a lot of collets because you end up with a bunch of machinery all using a different ER size.

My lathe has a MT3 taper in the tailstock and a MT4 in the spindle so it sort of made sense to stick with this for me. All my large drills are either MT2 or three, thus I can use them in both machines. I have never used R8 so I can't say which is better, my advice to any hobbiest would be to stick to the system that is the most popular in the country you reside in, that way you are more likely to pick up old tooling at car boot sales that will fit your machine, particularly if you are a bit of an old scrounger like me!
Cheers, Peter.

I have to agree with this, it is just around here MT spindle tapers are very uncommon in milling machines. At least in small machines they are uncommon. Some of the older mills did have MT tapers but they are long out of production.

 

[marvin_schwartz]

Have to stop thinking about this mill. every time I do I come up with another question.

The latest is. Does the supplied drill chuck and shank come with a threaded taper?
If so is it a 1/2" WW that would match the draw bar?
Which means if I make an M12 draw bar the drill shank is on no use. Right?
Or is it a simple tang end which doesn't use the draw bar?

 

[Journeyman]

You are over-thinking it a bit Just use 2 drawbars one M12 and the other .5"whit, it is only a matter of a few seconds to swap them over. Failing that it is easy to change the arbour on the drill chuck to M12. I had this problem with my smaller mill, supplied with 3/8"whit drawbar but most of my tooling is 10mm. I just made a new 10mm drawbar and the 3/8" is there if I need it. I rarely use the drill chuck, just put the drills into the ER collet - gives you more headroom.

You also say in an earlier post:

I'll go with MT3 tooling.
I'll definitely get the ER32 as I already have a number of bit's that have 20 mm shanks.

Now the question is do I go ER20 or ER11? I never considered the ER11 but if it works well it could be a great idea as I'm planning to get a cheap CNC engraver for plastic and PCB boards, which would take an ER11.
​

You only need the one ER32 milling chuck (at least to start with). The collets go from 1.5mm to 20mm so will hold any cutter up to 20mm if you have the full set of 21 collets. Most of the cheap Chinese CNC routers come with the collet holder system built into the high speed spindle so don't need an extra collet chuck.

Good luck with the new mill
John

 

[marvin_schwartz]

Sounds like the best option is to have 2 draw bars. The 1/2" WW and the M12 this way I have the best of both worlds.
Easy