# Benchtop mill for mitering



## sepp21321 (Apr 9, 2020)

Won't get a real mill down into the workshop. Any thoughts on benchtop mills such as this one:
https://boltontool.com/milling-machine-ZX45

2hp, R8, 700lb.

Anybody using such a size mill for mitering?

Best,
Sebastian


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## redoctober357 (Jul 8, 2016)

Damn, that looks like a good deal. I was looking at the smaller Grizzly 0704 for the same purpose. People miter on the Sieg x2 clones so that would be more than adequate.


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## Erichimedes (Jul 30, 2010)

I've seen several builders use a mill like that for mitering. You just have to use slightly higher speeds and you'll probably go through hole saws faster. Careful on the feed rate as well.

If you're anywhere near a city, stay on the lookout for used small horizontal milling machines. They come at half the price and often are much stiffer. I believe my Diamond 22-M is only 1000 lbs, and you could probably disassemble it to get that weight down a lot.

But it depends what you want to do with it. If you also want to do toolmaking, a vertical milling setup is easier to work with. Tradeoffs...


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## pvd (Jan 4, 2006)

That would not be my top choice. Milldrills really suck. As a guy who's been using milling machines for over 30 years, not having a Z on the table is a deal killer. Why waste the money.

Search around for a Rockwell/Clausing 8520-8525. Harbor Freight has a copy but I can't speak to that.

https://www.harborfreight.com/vertical-milling-machine-40939.html

A buddy of mine got a Rockwell/Delta and put some cheap chinese DROs on it. About the best you can do until you get a real vertical mill.

If it's just for mitering, most of the common framebuilder horizontals are small enough to get into basements and home power. Look for the Nichols or Hardinge units.

Anything that you buy will need to be tightened up for good work anyway, so you may want to look around well.


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## sepp21321 (Apr 9, 2020)

Thanks, will have a look at the clone and keep looking for a small sized horizontal.


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## Racecar (Oct 10, 2019)

I have a Grizzly mill about that size. It is 110/220, I'm Running on 110V, it works great. I'm sure it would miter steel tube just fine. Hole saws do wear out fast. If you could find the right size shell mill with carbide inserts, that would last 10X, then replace inserts.
I have a 2" cutter with square inserts, 4 cutting edges on each carbide.


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## wayold (Nov 25, 2017)

pvd said:


> That would not be my top choice. Milldrills really suck. As a guy who's been using milling machines for over 30 years, not having a Z on the table is a deal killer. Why waste the money.
> 
> Search around for a Rockwell/Clausing 8520-8525. Harbor Freight has a copy but I can't speak to that.


I have a Clausing 8520 (I don't think Rockwell had anything to do with these). I don't know anything about the HF clone, but the R8 spindle taper seems like a significant benefit. The 8520 uses Morse taper (MT2) and the 8525 Brown-Sharp. I've been able to accumulate all the tooling I need in MT2, but in some cases had to hunt for a long time. BS taper tooling is even less widely available. In contrast R8 tooling is everywhere.

FWIW the 8520 breaks down into (somewhat) easily moveable 200 lb chunks. When I was younger I was able to manually herc these parts into place in my garage (where they still live), but would want to use a hoist to move it now. Total weight is around 800 lbs.

Just as a quick review, the 8520 is a nice light duty machine, but the earlier comments about slow feed rates were spot on. Particularly in harder materials like steel you have to take it much slower than is possible on a full size mill - or even one of the heavier duty mill-drills. I've only used horizontals once or twice, but for a given size machine they seem to be a lot more rigid and capable of removing a lot more material in a hurry.

My old-guy shop (lathe and mill both built in 1967):


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## pvd (Jan 4, 2006)

wayold said:


> I have a Clausing 8520 (I don't think Rockwell had anything to do with these). I don't know anything about the HF clone, but the R8 spindle taper seems like a significant benefit.


I'm no expert on these so I may have referred to the wrong numbers. I would advise against buying anything that doesn't have an R8 spindle for sure. That's as important as having a Z-axis.


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## dr.welby (Jan 6, 2004)

The Grizzly version of the Clausing 8250 is the G0729. I've got one, and these little bench knee mills are a good sweet spot for the garage builder. You get a real knee, R8 collets, runs on 110 or 220. Easily moved with an engine hoist.


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## adarn (Aug 11, 2009)

most old horizontal benchtops you can find used for cheap are great for mitering. A lot of them are MT2, but you can just get an ER32 collet chuck and easily run any tooling (or just 3/4" hole saw arbors) that you want.


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## sepp21321 (Apr 9, 2020)

Thanks for all the valuable replies. Will try to get a smallish horizontal or go for sth like a 8250 clone. A first looksy in terms of horizontals left me quite optimistic. Should be possible to get sth like a Steinel SH4 here in Germany for cheap.

Thanks everyone,
Sebastian


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## Erichimedes (Jul 30, 2010)

Yes, a Steinel SH4 would be leaps and bounds better than any modern mill drill you would be looking at. Don't worry if it doesn't have an R8 taper, most of these old mills will have either a MT2 or MT3 or ISO 30 or 40 taper, all of which you can definitely find tooling for. Adam's comment about getting the adapter to ER32 is spot on, that's what I have in my Diamond for if I want to use collets.

Do your research about the weight however, these things can weigh more than you think. A good example is I bought a Nichols mill thinking it would be 1400lbs like many of them, but only learned later that it's a "heavy duty" model and clocks in at 2200 lbs, making it heavier than my Bridgeport or my Cincinnati lathe! But keep in mind they can be disassembled to move them.


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## Leafy1 (Feb 17, 2019)

Why are these style tube notchers not more popular with bike builders? They can do the smaller than the advertised 3/4" tubes with a V block in the jaws. And they'll certainly do a better job than a drill-mill at notching a tube.


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## Erichimedes (Jul 30, 2010)

Leafy1 said:


> Why are these style tube notchers not more popular with bike builders? They can do the smaller than the advertised 3/4" tubes with a V block in the jaws. And they'll certainly do a better job than a drill-mill at notching a tube.


Nope. They're a nightmare with thin wall tubing, much less heat treated thin wall tubing.


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## smashysmashy (Oct 18, 2013)

pvd said:


> I'm no expert on these so I may have referred to the wrong numbers. I would advise against buying anything that doesn't have an R8 spindle for sure. That's as important as having a Z-axis.


The rf45 style mills have a precision Z axis. They are one of the prime cnc conversion candidates. I'm not sure why you think the knee type z is mandatory. You might be confusing it with the rf40 round column machines, which do not have a precison Z (they are more like a drill press).

The only thing that you really "need" for mitering is lots of clearance and table room for fixtures, and a pivoting head with generous quill travel - and of course a precision x, y, and z.

If you have room and power and willpower, HGR surplus often has used bridgeports in good condition for $1000-$2000. These might be a better choice than any of these mini machines. If you have any inclination for and on the cheap cnc conversion later though, the RF45 types machine, the G0704 types are ideal.


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## Leafy1 (Feb 17, 2019)

Erichimedes said:


> Nope. They're a nightmare with thin wall tubing, much less heat treated thin wall tubing.


I never ran into issues with 049 wall 4140. The clamping doesn't look any different from most of the tube jigs I see for use in mills. I guess if you need to make paper thin tubes you could just make your own round tube clamp inserts in a drill press the same way I've made various size shock shaft clamps.


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## pvd (Jan 4, 2006)

smashysmashy said:


> The rf45 style mills have a precision Z axis. They are one of the prime cnc conversion candidates. I'm not sure why you think the knee type z is mandatory.


In manual milling, we need both a z-axis and a quill. They do different things. Just a quill is total bull$hit. CNC is a different animal.


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## smashysmashy (Oct 18, 2013)

pvd said:


> In manual milling, we need both a z-axis and a quill. They do different things. Just a quill is total bull$hit. CNC is a different animal.


The mill in the link in the OP has a Z axis.


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## pvd (Jan 4, 2006)

smashysmashy said:


> The mill in the link in the OP has a Z axis.


No. That's a quill. In manual vertical milling we need both a quill and a z-axis.


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## smashysmashy (Oct 18, 2013)

pvd said:


> No. That's a quill. In manual vertical milling we need both a quill and a z-axis.


I don't think you know what you are looking at. It has a quill and a z axis with 15" travel or so. The crank for the Z is on the column, lower right side. it moves the whole head up and down precisely on dovetail ways. the quill is in the head and moves a few inches like any other mill or drill quill.


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## pvd (Jan 4, 2006)

smashysmashy said:


> I don't think you know what you are looking at.


I know exactly what I'm looking at. A mill-drill without a z-axis. The height is adjustable, but that's not the same as having a precision lead screw.
I've been working in machine shops for 30 years. I know a toy when I see one.


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## smashysmashy (Oct 18, 2013)

pvd said:


> I know a toy when I see one.


Clearly you don't and 30 seconds of googling would have got you 1000 pictures of the uncovered z axis assembly.










It has a precision lead screw on the z, you can buy these with dro's and power feeds as upgrade options. The entire reason these are the original CNC conversion choice is because they have a precision z axis. just replace the hand crank with a stepper, and done. these machines have exactly the same milling motions as any knee mill, just upside down.

There's a number of machines that for this category of "mini mill" - technically benchtop bed mills, NOT mill drills. The rf45 is the first, the original, made by rongfu in Taiwan and copied by everyone since. On the smaller end is the BF30, BF20(g0704) and Bf16(g0758) made by Weiss, originally designed by Optimum Germany. The bf16 might be a little too small for mitering though, it only has 7" z travel and 2" on the quill.

Machines like the original X2 and RF40 are the ones that don't have a precision z axis. The X2 has a low grade rack and pinion, and the RF40 has a keyed round drill press column.

When you are giving people advice on expensive things to buy with their money, you need to make sure it is accurate, otherwise it isn't very helpful and can cost them money and time. You don't have to LIKE the benchtop bed mill style of machine, but it is absolutely every bit as capable as a knee mill of similar size (at least for xyz moton).

I haven't been a machinist for 30 years... But my TOS Kurim FNK25 is from 1976... so, do I win that pissing contest?


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## pvd (Jan 4, 2006)

smashysmashy said:


> Clearly you don't and 30 seconds of googling would have got you 1000 pictures of the uncovered z axis assembly.


I reffered to the owners manual for the machine in question. It was very clear.

https://boltontool.com/pdf/ZX45.pdf


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## smashysmashy (Oct 18, 2013)

It is very clear in that manual that is has a precision lead screw z axis with a crank on the lower right (item K page 4, screw assembly seen on page 18 item 45, identical to the one I posted above). I do agree they don't explicitly state "z travel". They give you nose to table, which is 17".


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## pvd (Jan 4, 2006)

That's a jack. Not useful during actual machining. No dial, no registration. I know that folks are desparate to imagine that a mill-drill can be used for machining but they really are a waste of money.


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## pvd (Jan 4, 2006)

Have you actually used the system that you are espousing? For real machined parts?


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## smashysmashy (Oct 18, 2013)

pvd said:


> That's a jack. Not useful during actual machining. No dial, no registration. I know that folks are desparate to imagine that a mill-drill can be used for machining but they really are a waste of money.


it has a scale up the side of the column. its nor more a jack than the crank on a knee mill.


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## smashysmashy (Oct 18, 2013)

pvd said:


> Have you actually used the system that you are espousing? For real machined parts?


I have a BF16 which is similar but smaller, my friend has that exact RF45 mill. I also have a TOS FNK 25, which is a 4000lb knee mill (imagine a Bridgeport, then put that Bridgeport on the table of my TOS). The TOS is nice, but other than size, it cant really do anything the mini bed mills cant. In some ways the RF45 is more rigid as well, because the turret ram on the TOS introduces a lot of flex.

Do you own an RF45 variant?


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## pvd (Jan 4, 2006)

This is a ZX45


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## smashysmashy (Oct 18, 2013)

pvd said:


> This is a ZX45


It's an rf45 clone. rf = rongfu, so yes, they give it a different name. Same machine.

This isn't a debate here. you're just wrong.


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## pvd (Jan 4, 2006)

According to the manual and the construction of the tool in question, I'm not. The real point here is that you really shouldn't waste your money on mill-drills. That's the point.


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## smashysmashy (Oct 18, 2013)

to add some clarity for other people...

This is a pic of the side of the machine I have, the wmd16v (bf16, g0658)









Because my machine is small, they put the hand wheel at the top, with no side crank. It has a lead screw, and a dial set, like the x and y axes, plus a scale on the side of the column. Head can swivel 90 degrees to make it horizontal although not as useful as a horizontal in the long axis. This machine is identical the bf20/g0704/wmd20/wmd25 except smaller, about 160lbs.

The RF45 (zx45, bf45, ta45, za45, and whatever other name it has) it basically identical, except it had a crank on the size, because it would be hard to reach a handwheel on the top of the column.


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## smashysmashy (Oct 18, 2013)

You suck... 



There is indeed no scale on the one in the OP, and no dial on the crank. Well isn't that lame. Its still a precision z with lead screw, but tis not going to be super useful without measurement. Every other one I've seen has a setup like mine - like the grizzly. Maybe the people that made this one are catering to conversion (where the people throw away most of the mechanicals so there is no point paying for them)


You're definitely wrong about mini mills as a general concept, but that one in the OP, maybe not the one to buy.

/me runs away


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## Erichimedes (Jul 30, 2010)

Leafy1 said:


> I never ran into issues with 049 wall 4140. The clamping doesn't look any different from most of the tube jigs I see for use in mills. I guess if you need to make paper thin tubes you could just make your own round tube clamp inserts in a drill press the same way I've made various size shock shaft clamps.


.049 isn't thin wall. Even .035 is pretty thick for bikes. I'm talking about .028" wall heat treated stuff. Trust me, you want a milling machine.


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## smashysmashy (Oct 18, 2013)

Erichimedes said:


> .049 isn't thin wall. Even .035 is pretty thick for bikes. I'm talking about .028" wall heat treated stuff. Trust me, you want a milling machine.


(unrelated to mill type) does anyone use abrasive hole saw instead for hard tubing?


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## Little_twin (Feb 23, 2016)

I have to agree with PVD here. Even though there is a column with a scale I find it very hard to believe you could hold anywhere near the accuracy you can with a precision knee.

Beyond the argument of precision of adjustments, bench top mills are small and the work envelope will become very limiting very quickly. When I was searching for a mill it was recommended by a friend who is millwright, “buy the biggest machine you can”. I ended up with a series 1 Bridgeport with a 3hp variable speed head. I’m glad I got it, I’ve already realized how limited my work would be had I ended up with a smaller mill. Now I’m looking for another because I want to have machines set up for dedicated processes, and still have a machine free for general use. 


Sent from my iPhone using Tapatalk


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## Cord (Dec 10, 2006)

How dull, I preferred this thread when there was arguing. I know a lead screw when I see one, and I’ve been a machinist for 34 years.


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## smashysmashy (Oct 18, 2013)

Cord said:


> How dull, I preferred this thread when there was arguing. I know a lead screw when I see one, and I've been a machinist for 34 years.


it has a leadscrew dumbass, it just doesn't have a dial for measuring how far that lead screw has moved.

better?


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## Cord (Dec 10, 2006)

smashysmashy said:


> it has a leadscrew dumbass, it just doesn't have a dial for measuring how far that lead screw has moved.


But I know what a milling machine is. I've seen more swarf than you!!!

This is more like it!


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## smashysmashy (Oct 18, 2013)

I design and manufacture milling machines.

Do I win?


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## Cord (Dec 10, 2006)

smashysmashy said:


> I design and manufacture milling machines.
> 
> Do I win?


Prove it! Where's your portfolio.


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## smashysmashy (Oct 18, 2013)

Cord said:


> Prove it! Where's your portfolio.


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## smashysmashy (Oct 18, 2013)

So I was looking for a terrible image of a cnc and I found that for $200.. Kinda amazing you can get something that nice for $200.

This one on the other hand... Not $200....


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## Cord (Dec 10, 2006)

glad this thread is keeping you entertained now !!!!


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## smashysmashy (Oct 18, 2013)

I made a chainring!









OK, half a chainring... I may have selectively used a blurry picture taken before something bad happened (don't use alcohol for coolant on an mdf fixture).....


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## pvd (Jan 4, 2006)

smashysmashy said:


> I design and manufacture milling machines


You make routers. Those aren't really milling machines. Anyway, you seem like some young "maker" that's never set foot in a real shop. There's a big difference with cosplay machining and real machining. That's all fine, just stop faking in front of others.


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## smashysmashy (Oct 18, 2013)

pvd said:


> You make routers. Those aren't really milling machines. Anyway, you seem like some young "maker" that's never set foot in a real shop. There's a big difference with cosplay machining and real machining. That's all fine, just stop faking in front of others.


Would be kinda hard to make those machine frames without setting foot in a real shop, but you can believe whatever you like if it makes you feel better.

Speaking of pizza... I just noticed how expensive grizzly machines have gotten because of the tariffs on Chinese equipment. Haven't looked at them in many months. The G0704 is double what it used to be. Makes looking at used "industrial" machines more appealing if you have room and power.


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