# Horizontal Milling Adapter for a Bench Top Vertical Mill



## blanik (Dec 17, 2022)

Greetings,

I have a small bench top vertical milling machine (a Sieg SX2.7 photo attached for info) that I've owned for seven years now.  It's proven to be a very capable machine for the work that I do.  Recently, I've started on a new project that requires me to machine three gear racks, with each rack being 350 mm (~ 14 inches) long.  I made a flycutter type gear cutter and successfully made a short gear rack as a test.  However I don't have enough vertical travel on the mill to cut a 350mm long gear rack.  

Ideally, using a horizontal mill would be the solution - but I don't have room for a second milling machine in my workshop, and in any case - if I managed to find a suitable used machine in Australia, cost of machine and tooling would be prohibitive anyway.

So, I'm wondering if anyone has ever seen a design or plans for a Horizontal Milling Adapter for a bench top Vertical Mill.  I know that this type of adapter is available for some full size mills, so the concept is obviously feasible.

So over to the experts.  Has anyone seen a design (or have some ideas for a design) for a shop made Horizontal Milling Adapter for a benchtop Vertical Mill?

Best regards,

Roy G


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## RM-MN (Dec 17, 2022)

There are times to make your own designs and there are times when it is more practical to just buy.  Unless you expect to do a lot of these racks, buying one from someone who is already making them in quantity will be the better choice.  You have already proven that you can make a shorter one but the expense of a horizontal milling adapter will be high if they are even made for your mill.


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## Brian Rupnow (Dec 17, 2022)

Chuck Fellows built his own 90 degree adapter to change his vertical mill to a horizontal mill, and did a complete thread on this forum a few years ago. Do a search for Chuck Fellows and maybe you can see how he did it.---Brian


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## djc (Dec 19, 2022)

As you say, you can buy R8 right angle heads for larger machines. If you search for 'R8 right angle head' you will see what they look like and cost (e.g. AliExpress is circa. $400 US + plus shipping).

They work by clamping onto the quill of the machine, but if you look at how they are made, the part that clamps onto the quill is removable, so you could adapt to your own machine (bush down or make anew).

It would be difficult to make one for the price of buying one - you need a male R8 taper to go in your spindle, a set of bevel gears and a complete female R8 spindle.

With some ingenuity, it would be possible to cut the rack on your existing machine. Mount the rack blank vertically on an angle plate, cut half the teeth and then flip it over.

Once flipped, blue up the highest tooth space and adjust the head up and down until the cutter enters the tooth space centrally.

While the rack you want has to have 350mm travel, why does it have to be one piece that spans that distance?


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## rick9345 (Dec 19, 2022)

blanik said:


> Greetings,
> 
> I have a small bench top vertical milling machine (a Sieg SX2.7 photo attached for info) that I've owned for seven years now.  It's proven to be a very capable machine for the work that I do.  Recently, I've started on a new project that requires me to machine three gear racks, with each rack being 350 mm (~ 14 inches) long.  I made a flycutter type gear cutter and successfully made a short gear rack as a test.  However I don't have enough vertical travel on the mill to cut a 350mm long gear rack.
> 
> ...











						McMaster-Carr
					

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Many Choices and lengths


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## MRA (Dec 25, 2022)

If you want to see a daft way to do this using an attachment (which I bought, but I guess you could make one) on a lathe or a miller, have a look towards the end of this thread






						Adapting a pillar drill for vertical milling - new chuck
					

Hi folks  I have an old Elliot Progress No1 bench drill which is clamped up to a small 3 axis table - which looks like it came from an equally ancient small milling machine.  The drill is quite good - heavily made cast iron body, large spindle for a small bench drill, very little run-out...




					www.homemodelenginemachinist.com
				




I did say it was daft - but it works.


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## toolingjim (Dec 26, 2022)

There were two articles in Home Shop Machinist magazine in the March/April and May/June 1995 issues that detailed a fairly simple right angle milling head. The information there might help inspire someone as it did me.
Inspired by the above and the commercial Bridgeport right angle head, I built a right angle head for my rf-30 mill drill with all the bells and whistles: Timken (tapered roller) bearings, r8 spindle, 1/2 speed commercial helical bevel gears, drawbar, alignment surfaces on both sides. It turned out beautifully---and I have yet to use it. The project I built it for went away, and I have yet to find another. Every once in awhile I take it out of its case and turn the spindle. It does prove that it can be done.

Jim
(just a guy who likes to build stuff)


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## Drawfiler (Dec 27, 2022)

Another solution would be to make, grind or buy a suitable endmill and mill the rack by using x axis feed, the cutter is a simple V shape ground to  the pressure angle of the gears.


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## Poppy Ott (Dec 27, 2022)

I think I have cut gears and racks by just about every method there is except with a Fellows Gear Shaper.  With regard to cutting racks I have cut them on my Atlas shaper, using the  horizontal spindle on the mill, and with the vertical spindle using end mill cutters reground to an included angle of 29°.  Right now I am in the process of cutting rack teeth in one of the tube rails of my ancient ShopSmith using a right angle head on the vertical spindle.  The name plate of the attachment is Tree; I don’t know if these are still made but it wouldn’t hurt to look for a used one.  However, if you have a tool and cutter grinder, Blanik, I’d recommend you do what Drawfiler suggested and regrind an endmill.  I used this method years ago when making the rack & pinion talestock for my lathe.  I went on an explore and sure enough, even though I have not used this method since, I still have the repurposed end mills.  They did a good job of making the rack. 

Lacking a T&C grinder, a variation of the method is to make a ‘D’ bit from drill rod.  It will take at least two passes to cut each tooth space with the end mill, and more with a D bit cutter, but the D bit it will do the job and as you appear to be at the same point in equipping your shop as I was 30+ years ago when I modified my lathe, I think the vertical milling approach to cutting a rack is your least complicated option.


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## blanik (Jan 3, 2023)

Poppy Ott said:


> I think I have cut gears and racks by just about every method there is except with a Fellows Gear Shaper.  With regard to cutting racks I have cut them on my Atlas shaper, using the  horizontal spindle on the mill, and with the vertical spindle using end mill cutters reground to an included angle of 29°.  Right now I am in the process of cutting rack teeth in one of the tube rails of my ancient ShopSmith using a right angle head on the vertical spindle.  The name plate of the attachment is Tree; I don’t know if these are still made but it wouldn’t hurt to look for a used one.  However, if you have a tool and cutter grinder, Blanik, I’d recommend you do what Drawfiler suggested and regrind an endmill.  I used this method years ago when making the rack & pinion talestock for my lathe.  I went on an explore and sure enough, even though I have not used this method since, I still have the repurposed end mills.  They did a good job of making the rack.
> 
> Lacking a T&C grinder, a variation of the method is to make a ‘D’ bit from drill rod.  It will take at least two passes to cut each tooth space with the end mill, and more with a D bit cutter, but the D bit it will do the job and as you appear to be at the same point in equipping your shop as I was 30+ years ago when I modified my lathe, I think the vertical milling approach to cutting a rack is your least complicated option.


Many thanks for your suggestions.   I especially like the idea of regrinding an End Mill, or making a suitably shaped D-Bit.   (Luckily I do have a Chinese made D-Bit Grinder that I was given after it was flood damaged - new bearings everywhere and a thorough clean and some general fitting work got it running like new ... maybe better than new.)

Thinking about the geometry of an endmill ground down to a 29 degree point ...    I assume that the 29 degree end mill would not be center cutting, and so I would need to first cut a slot to the required depth of the rack gear, then use the 29 degree end mill to shape the teeth.  Would there be any benefit if I choose to grind a slot milling cutter (maybe also called a center cutting end mill in some countries)?

Thanks for the ideas.
RoyG


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