# Build my own milling machine



## Traian Dumbrava (Sep 5, 2019)

Hi everyone
I'm new here and even wit website but this is different story
So my intention to build whole milling machine and need some informations about cast iron used I have chosen grey cast 250 grade or sG500-7 and don't know witch one to use for , even for column any help here thanks


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## ddmckee54 (Oct 4, 2019)

Have you checked out either the AlloyAvenue, or Home Foundry forums?  They're casting forums and love to hear from anybody casting iron.

Don


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## tornitore45 (Oct 5, 2019)

Keep a good log of your expenses, and when your machine is complete compare with a brand new Chinese import of comparable capabilities.
Is common attitude among HSM to spend $200 to make a tool that can be purchased for $50.  Do not ask how do I know.


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## kwoodhands (Mar 31, 2020)

Traian Dumbrava said:


> Hi everyone
> I'm new here and even wit website but this is different story
> So my intention to build whole milling machine and need some informations about cast iron used I have chosen grey cast 250 grade or sG500-7 and don't know witch one to use for , even for column any help here thanks



I think you are making a mistake building your own mill. There probably are many used mills or even new ones that would cost less than trying to make your own. I have an acquaintance who bought a new South Bend lathe, deep pockets I suppose. Now he wants to save money and build his own mill. I tried to talk him out of it but apparently he knows more than me.
He bought a new 20" Grizzly DP and wants to convert it to a mill. 
He could of bought a mill for the money he paid for the DP. 
I stopped trying to help him, his money and time.  I admire your penchant for casting your own tools but how about casting something like a rotary table or engine blocks etc. This would be more efficient use of your skills.


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## Apprentice707 (Mar 31, 2020)

I can understand you wanting to build anything for yourself, but there comes a time when self build becomes a chore and not a pleasure. I once converted a small drilling machine into a milling head for use on my Myford Super 7. It took a long time and did not really achieve what I was looking for, in the end, I found a Chinese made milling machine on a stand for sale on eBay for £500, a bargain and a lovely machine.
Incidentally, I still use the drilling machine as a drilling machine but with much better accuracy since I replaced the bearing system and reworked the rack feed. 

Good luck, but think carefully about homemade machine tools.


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## jacobball2000 (Mar 31, 2020)

I have a sears craftsman lathe from the 60's 6in beautiful machine. And a Harbor freight  lathe from China "junk" I have to be constantly working on it to keep it going! I built my own horizontal mill from two heavy channel iron. The first thing you have to do is make sure it is very square at the base. Like building a house if the floor is not square nothing else will square up. The problem I had most was cutting the quarter inch channel down the length of the spindle.  I found at a local store called "barring belts and chain" one inch electric motor shaft collects that worked good as alignment and holders for my cutting wheels. The cross slide I got for 50$ the collects for 11$ a piece. The spindle from scrap yard for .30 per pound. It was two feet long so you can figure the weight from that. On my big mill I got from a friend has attachment for vertical mill. Which I will try to make later. I don't have room in my very small shop for the big mill yet.


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## threesixesinarow (Mar 31, 2020)

It might be a little less impractical to make something that would be difficult to buy, either because it’s rare, expensive, or has never existed before - S_J_H’s boring mill, and Jackary’s ‘Stepperhead’ are great examples:

Cnczone boring mill build thread


			Stepperhead Machine
		



Here’s my more ordinary home made mill, I’d mentioned it on the other, ‘home made lathe’ thread:







I cheated and reused many parts I already had.


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## BIGTREV (Apr 1, 2020)

I looked at milling on my Colchester Chipmaster lathe, but buying all the parts,(and still wouldn't be really up to the job) would cost more than I could buy an older/proper milling machine, one in need of restoration. I bought a Pallas HO universal milling machine for £300.
Cheers.


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## Peter Twissell (Apr 1, 2020)

Hi Traian,
If you're building a mill only because you need one, then I agree with others that it would be much quicker and cheaper to buy a used machine.
If you're building a mill because you want to build your own machine, then I'm sure you will get plenty of support from this website.
I have not built my own mill or lathe, but I've made a number of attachments for both and various other tools, including a large set of bending rolls for steel plate and tube.
Please post photos and details of your progress.


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## jacobball2000 (Apr 2, 2020)

This is what I built. The only problem I have had was dulling the blade on steel which is funny considering it is a HHS blade. The one thing I didn't know was the support arm was to be solid steel bar. The knee adjustment was an old screw jack inverted and welded in place also making sure it was very square with the support. There's more that can be done to it ; ) but it works for now.


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## Jrcfiero (Apr 2, 2020)

jacobball2000 said:


> This is what I built. The only problem I have had was dulling the blade on steel which is funny considering it is a HHS blade. The one thing I didn't know was the support arm was to be solid steel bar. The knee adjustment was an old screw jack inverted and welded in place also making sure it was very square with the support. There's more that can be done to it ; ) but it works for now.


Seeing the size of your pulleys and the diameter of your cutter, I would guess that you’re dulling your cutters because your speed is way too high.


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## jacobball2000 (Apr 2, 2020)

The smallest pulley on the motor is 1"in" the spindle shaft pulley is 3 "in" making the cutting tool rpm to only 583.  The motor run's at 1750. So that should be slow enough for the tool.


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## rick9345 (Apr 3, 2020)

jacobball2000 said:


> The smallest pulley on the motor is 1"in" the spindle shaft pulley is 3 "in" making the cutting tool rpm to only 583.  The motor run's at 1750. So that should be slow enough for the tool.


Much too fast,if that cutter is 3", RPM needs to in the 50-100 Rpm. Machinery Hand Book would get a better RPM. Just my intuition.


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## jacobball2000 (Apr 3, 2020)

Looks like I need to get that book. The large blade I have is 6 to 8 in. The blade you see in the pic is 5" the I dulled was 6" But I seen slitting blades on here look like it was ran above 1750 rpm.


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## Jrcfiero (Apr 3, 2020)

jacobball2000 said:


> Looks like I need to get that book. The large blade I have is 6 to 8 in. The blade you see in the pic is 5" the I dulled was 6" But I seen slitting blades on here look like it was ran above 1750 rpm.


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## Jrcfiero (Apr 3, 2020)

A good speed to start at for mild steel is 90 surface feet per minute (sfm). If your cutter is 5” and your speed is 583, then sfm = .262 x 5 x 583 = 763 sfm. Too fast. 
That cutter should run about 70 rpm.


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## jacobball2000 (Apr 3, 2020)

Some of the math I been doing which is 35 (sfm). My speed should be 28 rpm. But that depends on the type of metal being milled. That's a lot of pulley changing. I have a auto-transformer. But I think I going to have to hook up some type of tachometer. What about vertical mill's they run at higher speeds right. I am reading a book on "how to use a milling machine" They talk about chip size- chip per tooth- tooth per inch. And it all ended up to a rpm of 2,400. making me think I need to build a vertical mill to.


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## awake (Apr 4, 2020)

Jacob, as a comparison, my Bridgeport has a range from 60 rpm up to 3000. For a 1/2" diameter High Speed Steel cutter in mild steel, the proper speed is around 500 rpm. For a 1/4" cutter, double that to 1000; double again to 2000 for a 1/8" cutter. Conversely, halve that to 250 rpm for a 1" cutter.

For cutting tool steel, speeds drop; for aluminum they increase. If using carbide cutters, the recommended / possible speeds are much higher - but I rarely use carbide, so I don't have those off the top of my head.

As I understand it, rpm is based pretty much entirely on type (HSS or carbide) and diameter of cutter in a certain type of material. Chip load is a different issue; this has to do with how many flutes the cutter has and the speed of travel. Or to say it another way, to change the chip load, you change the speed of travel, not the rpm. Again, as I understand it - I claim no expertise, just some home-shop experience.


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## clockworkcheval (Apr 5, 2020)

For whatever its worth, there is a distinct negative about a milling attachment to a lathe. You bang your head against it. After banging my head for three years I sold it to somebody who was really interested in a multipurpose machine. I never heard from him again.


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## MrMetric (Sep 21, 2020)

If your passion is to build machinery, then go for it! If your passion is to build other things and need the machinery to do it (in other words, you really don't *want* to build machinery but *need* to so you can build other things), then I echo the other postings saying that there is a LOT of good iron out there which would probably serve you well.

You would be surprised what you can find in junk yards.  In fact, it can bring tears to your eyes sometimes.  If you were in the US, there is what was probably a beautiful Hardinge HLVH lathe on a government website right now.  The only problem is that it is in Georgia (I think) and clearly was left out in the rain for the last 5 months.  The thing is one giant rust bucket.  In fact, the tray is full of water.  Ironically, in this case it is not a typical DoD auction either because their "starting bid" is $1500, while most auctions start at $5 (from what I recall).  But not all junk yards are like that.  And sometimes you can get lucky with just CraigsList

I was casually looking at CraigsList once and saw a nice, but older, CNC bed mill. I contacted the guy and told him up front that I really was interested only in checking out its size in real life, but that I already had a mill.  I was not someone who could justify getting rid of my other and buying his.  Well, 6 months later the guy called me.  He had a proposal.  He didn't know the machine (but knew it worked because his father had bought it new) and wanted the space.  If I paid for a rigger to move it out and then reposition two large machines, I could have it for free... with tooling.  He even let me keep the machine there for almost 4 months while we figured logistics out and we each had vacations.  In the end, I got a really nice machine for about $400 (and then spent another 1K doing stuff to it that I felt needed to be resolved... but that was my choice).  

Now, those types of deals are rare enough that you can't wait for them, but there definitely are a lot of less sweet, but still very good, ways to purchase very good iron out there.  And if you are willing to scrape ways, then that opens up a whole new avenue... And don't discount the cost of gears in a threading box either.  They are expensive.  On a machine you buy, however, you'll likely have all of that already.... unless you are planning on an electronic leadscrew, etc.

If you are truly interested in making your own machine because you love machinery (a very viable love, I might add... a hobby in its own right) then there are some excellent videos/sites out there which chronicle people's progress.  Most of these are CNC bed mills, but not all of them.  And some of the designs are really really good.  I happen to love machinery and I have often felt that if I had room, I'd like to build a bed mill.  But, I only have so many hours (and space).

In summary... It is all really about your motivations. If you *want* to build, then do a bit more searching on the internet.  Otherwise, you are probably better off searching the back corners of used machinery dealers.  They'll likely have some smaller manual machine that has been sitting there for years.  Sure, they'll ask $4000 for it, but they very well may take $500.


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## SmithDoor (Sep 21, 2020)

Today it would be welded steel 
The drawback  is you have to stress relief  be for any machining. 
Just A big BBQ pit and let set for few day covered .

Dave 



Traian Dumbrava said:


> Hi everyone
> I'm new here and even wit website but this is different story
> So my intention to build whole milling machine and need some informations about cast iron used I have chosen grey cast 250 grade or sG500-7 and don't know witch one to use for , even for column any help here thanks


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## MrMetric (Sep 21, 2020)

I always love your backyard machinist's approach to "getting stuff done", Dave. Most of us don't have access to heat treaters with giant ovens, multi million dollar plants, etc.  So, yeah, dig a big hole, dump some charcoal in there, light 'er up, and cover it.  It is outside my knowledge of how well this works, frankly, but I always enjoy the alternative approaches you frequently put out.  There were some good posts you had recently regarding the amount of shrinkage and expansion on different material.  I printed out those charts and put them in my booklet of, "before you take a hammer, idiot, try this."  Sure, I know the fundamentals of this, but now I have it backed up by some tangible charts to understand how much tolerance is available...


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## MrMetric (Sep 21, 2020)

Good God! It actually sold for some serious money!  I am really quite surprised... Here is the machine I was talking about:









						Hardinge HLV-H Lathe
					

1.5 Horsepower, 460 Volts




					www.govplanet.com
				




This will make any machine lover roll over and cry... I bet the guys who used to work on the machine would just shake their heads and ask "why on *earth* would you stick that out in the rain?"


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## SmithDoor (Sep 21, 2020)

I had heat treating a large weld steel jig. My largest oven up to 15" ID.

You can not machine a large part with stress relief or it will twist as machine the part.
This also happens with aluminum too but this takes 30 days. 

1) Ship out of town to larger oven
2)  Think outside the box look how backyard shops do the job. 
3) Look a kiln use for potty but try find any has big kiln that will put steel in kiln. 

Will someone  got lucky and dug a big hole. The get job was done. It save on shipping and the cost of heat treating and no cost for backhoe.

Dave 



MrMetric said:


> I always love your backyard machinist's approach to "getting stuff done", Dave. Most of us don't have access to heat treaters with giant ovens, multi million dollar plants, etc.  So, yeah, dig a big hole, dump some charcoal in there, light 'er up, and cover it.  It is outside my knowledge of how well this works, frankly, but I always enjoy the alternative approaches you frequently put out.  There were some good posts you had recently regarding the amount of shrinkage and expansion on different material.  I printed out those charts and put them in my booklet of, "before you take a hammer, idiot, try this."  Sure, I know the fundamentals of this, but now I have it backed up by some tangible charts to understand how much tolerance is available...


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## Chiptosser (Sep 22, 2020)

What tools or equipment, experience do you have ?
There are a lot of factors and knowlege, reference base involved in building a mill.  Do you have somone available close at hand to help you? It gets mighty expensive scraping material and discouraging to boot.


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## goldstar31 (Sep 22, 2020)

Chiptosser said:


> What tools or equipment, experience do you have ?
> There are a lot of factors and knowlege, reference base involved in building a mill.  Do you have somone available close at hand to help you? It gets mighty expensive scraping material and discouraging to boot.


I agree with with Chiptosser and I simply don't think for a moment that most posters here have even got near to 'making a milling machine'
There's and an old saying that one needs a lathe to make a lathe and i have no doubt that this applies to making a mill.
As a non engineer, I have 'sort of done it' by making a Westbury Mill Drill but not from scratch.

The castings were dropped at the local college and rough machined there. Apart from the headstock- that is. I bought that from the then Woking Precision Models at Queensferry jusst a stone's throw from the City of Edinburgh. I bored the thing at the college as an evening class student - and slit it to clamp to the column------AND IT NIPPED!!!!!!! It took hours to scrape it in.
The rough castings were done against 'references' which have yet to be mentioned here- and by HAND.
This was llong before the arrival of  home workshop mills mainly from China.

To answer the most obvios question-- NO I would not reppeat the exercise.
Just to whet appetites, might I humbly suggest that you buy a scrap mill and scrape it back to a sort of perfection

When you think that you have seen it all-- make a Quorn tool and cutter grinder. It CAN be done on a lathe with a 7 inch swing-- which is what I used. 

My thoughts---- and experiences, naturally


Norman


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## Richard Hed (Sep 22, 2020)

jacobball2000 said:


> Looks like I need to get that book. The large blade I have is 6 to 8 in. The blade you see in the pic is 5" the I dulled was 6" But I seen slitting blades on here look like it was ran above 1750 rpm.


You can download old copies of Machinery's Handbook


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## mikelkie (Sep 22, 2020)

Traian Dumbrava said:


> Hi everyone
> I'm new here and even wit website but this is different story
> So my intention to build whole milling machine and need some informations about cast iron used I have chosen grey cast 250 grade or sG500-7 and don't know witch one to use for , even for column any help here thanks


Like  MrMetric say if you like building machine tools go for it, or you will be wasting time and and get frustrated and may even loose enthusiasm. if you were close by and with the strong pound you could buy a working Bridgeport from me for thirteen hundred pounds incl. vice and feed on X axis.
I would look around first for a used machine since they were build in your country


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## SmithDoor (Sep 23, 2020)

I agree.
It may time find the size you looking for mill.
The Bridge Port type mill is simple to find but the weight and size may not fit your shop or needs. The small size harder to find.

To rebuild  is simple 
The machine tool rebuilds use Devcon epoxy, brass  flat bar or  plastic  for worn slides and reshaping 

Dave 



mikelkie said:


> Like  MrMetric say if you like building machine tools go for it, or you will be wasting time and and get frustrated and may even loose enthusiasm. if you were close by and with the strong pound you could buy a working Bridgeport from me for thirteen hundred pounds incl. vice and feed on X axis.
> I would look around first for a used machine since they were build in your country


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## dazz (Sep 24, 2020)

Hi
Rather than build a machine, an easier route would be to rebuild an old worn out machine.    They are cheap and would provide a good foundation to regenerate a sound machine.

Dazz


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## MrMetric (Sep 24, 2020)

If size is a concern, here are a few alternatives beyond the new, Chinese mill/drill machines:
1. Emco Maier Super 11 with a milling attachment (not exactly small, but has both mill/lathe capacities, for better or worse)
2. Deckel FP1 - an awesome machine which has been around for almost a century. Older ones that need help can be amazingly cheap
3. Small belt drive BridgePort. These are substantially smaller than the normal ones
4. Rockwell mill. Comes in a H/V flavor, if desired.  I had one for a while and it worked quite well
5. Hardinge horizontal mill..... and then put a Rosnok vertical head on it (or similar)
6. Sherline... These are quite a bit smaller than the machines above, but are very inexpensive, widely supported, and really very capable.  You'll find a lot of people here that have them and I think you'll be surprised what can be done with one.
7. Aciera... probably not a great option because these are pretty small (F1 was for the instrument/watch trade) and are now sold for a premium.  They are nicely built if you want tiny though and sometimes you can get them for cheap (or even free... I know!!!!)

There are many others too... I'm just giving you some ideas.  And, in fact, if you really have some specialized thing you want to make that is small, Sherline sells parts for reasonable prices.  That is also an option.  I don't own any Sherline stuff (well, other than a rotary table), but I give them really high marks for balancing availability, cost and capability.  I think they provide an excellent way for people to get into the hobby, and they have an excellent creative eye towards different tooling...  They also seem to have one of the strongest financial foundations in the small machine market.


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## TSutrina (Sep 25, 2020)

Concrete bridge port milling machine has been built as other big commercial machines.  Concrete is typically made with epoxy replacing concrete. Machine Casting – Castinite However actual concrete machines were build during WWII to produce production parts.  The base line is patent 1154155 by L. I. Yeomans  Sept. 1915  Articles on the web can be found.
The Multimachine Open Source Concrete Lathe Project is a standard concrete machine found on the web.  Sorry do not know the full site address: Build a Metal Lathe, Drill, and Milling Machine | Make:...      Other sources include Vintage Projects and Building Plans  CNC concrete casting:  

Popular Mechanics has many builds often by Romig  small mill concrete base it is horizontal  Popular Mechanics  Turned it into a shaper also PM article 
*Popular Mechanics - May 1930 - Page 870*

*Popular Mechanics - May 1923 - Page 86*

*Popular Mechanics - Jul 1922 - Page 129  lathe*


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## SmithDoor (Sep 25, 2020)

Back around 1810 they used wood with cast iron slides. By 1860's they used bricks and cast iron slides.

I have use concrete  in China made tools in the columns. See downloads 

Dave 



TSutrina said:


> Concrete bridge port milling machine has been built as other big commercial machines.  Concrete is typically made with epoxy replacing concrete. Machine Casting – Castinite However actual concrete machines were build during WWII to produce production parts.  The base line is patent 1154155 by L. I. Yeomans  Sept. 1915  Articles on the web can be found.
> The Multimachine Open Source Concrete Lathe Project is a standard concrete machine found on the web.  Sorry do not know the full site address: Build a Metal Lathe, Drill, and Milling Machine | Make:...      Other sources include Vintage Projects and Building Plans  CNC concrete casting:
> 
> Popular Mechanics has many builds often by Romig  small mill concrete base it is horizontal  Popular Mechanics  Turned it into a shaper also PM article
> ...


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## SmithDoor (Sep 25, 2020)

Look at all the drawings on Vintage Projects is the battery charger 3 different places. I guess  that is one that worked. 

Dave 



TSutrina said:


> Concrete bridge port milling machine has been built as other big commercial machines.  Concrete is typically made with epoxy replacing concrete. Machine Casting – Castinite However actual concrete machines were build during WWII to produce production parts.  The base line is patent 1154155 by L. I. Yeomans  Sept. 1915  Articles on the web can be found.
> The Multimachine Open Source Concrete Lathe Project is a standard concrete machine found on the web.  Sorry do not know the full site address: Build a Metal Lathe, Drill, and Milling Machine | Make:...      Other sources include Vintage Projects and Building Plans  CNC concrete casting:
> 
> Popular Mechanics has many builds often by Romig  small mill concrete base it is horizontal  Popular Mechanics  Turned it into a shaper also PM article
> ...


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## TSutrina (Sep 25, 2020)

Concrete is about ten times stronger in compression as tension.  A great starting point to understand concrete is Tyler Ley  youtube videos.  Primary goal is to keep concrete in compression.  when that isn't possible then fibers of may types are used to carry tension so that the tension in the concrete is lower.  If below the yield strength the concrete will not crack.  If it does crack the fibers help minimize the width of the crack.  The big advantage is the reduction in vibration of concrete for the same strength is much better then cast iron and much better then steel or aluminum.  The problem is that the machine is heavier when the strength is the same.  Thus few parts that move are made from concrete.  The knee of a mill is moved but not dynamically so it can be made with concrete.   the table for a hobby hand powered machine could be a mix of concrete and steel.


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## MrMetric (Oct 2, 2020)

I would guess that another problem with concrete in production products is that it is also fairly brittle.  If you need to move/ship a machine, there is probably a much greater chance that the machine could be damaged due to cracked concrete.  This could be mitigated, of course, by additives  which also increase the tension component that TSutrina refers to.

I love the idea of making a concrete machine.  I think it is a neat (and inexpensive) product.  I don't know that I think it makes *sense* to fabricate your own machine (as mentioned previously), but if the OP wants to do so, I hope he does.  I further hope that he chronicles his achievements (and frustrations) here.  In the end, we all share a common interest here in this forum, so hearing what others are doing is always fun.


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## goldstar31 (Oct 2, 2020)

I seem to recall that all of this has been hacked about here with the mention of epoxy resins as a binder for  filler for lathe and milling machines.

We seem destined to suffer  're-invent the wheel' syndrome.
---------------------------------------------------------------------

23Rd June 2018.  Epoxy filled granite by Niels Abildgaard!

I learned Pelmanism at a very tender age. At 90 it is still sort of working.

Write the name down in case you forget it

Norman


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## MrMetric (Oct 2, 2020)

Well, if we keep coming up with the same ideas, then we are obviously all geniuses or raving lunatics.  You decide.


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## clockworkcheval (Oct 3, 2020)

A good friend once explained that if you don't try to re-invent the wheel you won't really understand it.


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## TSutrina (Oct 4, 2020)

MrMetric said:


> I would guess that another problem with concrete in production products is that it is also fairly brittle.  If you need to move/ship a machine, there is probably a much greater chance that the machine could be damaged due to cracked concrete.  This could be mitigated, of course, by additives  which also increase the tension component that TSutrina refers to.
> 
> I love the idea of making a concrete machine.  I think it is a neat (and inexpensive) product.  I don't know that I think it makes *sense* to fabricate your own machine (as mentioned previously), but if the OP wants to do so, I hope he does.  I further hope that he chronicles his achievements (and frustrations) here.  In the end, we all share a common interest here in this forum, so hearing what others are doing is always fun.


Concrete or rather bricks held together with concrete building have been move without cracking the concrete or plaster, also brittle, in the building.  My parents two floor home was moved about 5 blocks without a single crack in the home.  Picked up off a foundation, rolled over a basement, onto the street, the 5 blocks, off the street, and over a new basement.  Then set down with in 1/4 inch of the ideal location.  Moving concrete structure takes care.


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## TSutrina (Oct 4, 2020)

I have been interested in building my own machines since I saw the Gingery designed home made machines: lathe, Mill, and shaper.  There are others all made from aluminium castings and steel ways that are flat bars.  Gingery-style homemade metal lathe builds | Make: But casting seem to be a complication that doubled the complexity of building a machine. And I do not see a significant supply of aluminum, a second complication.  
Concrete on the other hand, stone and sand are cheap and plentiful.  Also reinforcement components out of steel are also cheap and plentiful.  Casting patters are also typically wood.  How to make concrete less likely to fail, crack is understood and the information is available.  For example Tyler Ley has many videos on how to keep concrete from cracking.  Post stressing concrete is one of the best and easy to do for small items.  You can find a bench made with fiber filled concrete with a few theaded rod in plastic tubes bent into a shallow "U" shape to keep the concrete in tension.  Two inch thick and like 4 or 5 foot long strong enough for a two pound person to stand in the center.  Here is a reinforcement video from Tyler:     NASA had a contest to 3D print housing which using Mars materials would be the printing of concrete.  This is the video made by the second place team:  
Note that the stresses are always highest at the surface of the structure so cast iron components of machines are hollow.  Concrete machines also should be make hollow.  Say a wall thickness of 2 inch and maybe 3 to 4 inch around the active post stressed steel and the cast in place reinforcement steel.  To prevent cracks fibers of steel, glass for concrete or besalt would be used.  Bamboo has also been used, plant fibers.


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## MrMetric (Oct 4, 2020)

I've seen that done.  It is interesting.  I've also taken apart an unreinforced brick chimney that was in the middle of my house.  It was the opposite experience of your parents.  I live in earthquake country, and let me tell you.  I was stunned at how easily that chimney crumbled once the cap was off.  Yes, as a composite structure it was strong, but after the the top was off, a few whacks and the whole wall started crumbling away.  I don't miss that chimney at all.

Your parent gave a whole new meaning to, "I like this house... I don't want to leave!"


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## MrMetric (Oct 4, 2020)

There are a few 3D printed housing technologies that are being started up.  It is pretty nascent, but I personally think that they are really cool.  Ditto with ICF (insulated concrete forms).  I may do that for a basement sometime if I move.  I think that is kind of the cat's meow.  Very neat stuff.... You are right, though, concrete is an amazing substance... There are some really nice counters you can make with it.  Best of all, it is relatively inexpensive and eminently recyclable.


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## TSutrina (Oct 5, 2020)

I fixed the top of a brick chimney also.  Snow, ice, and rain destroyed the concrete holding the bricks together.  Took it down to the roof and then rebuild it up.  There was not reinforcement in the chimney thus any side forces would put the chimney in tension, break the bond to the bricks.   The shape of the Mars structures is to use gravity to keep the concrete in compression.  All the Roman stone and concrete structures are design to put the concrete in compression since their is no reinforcement.  The majority even in the earth quake prone Italy have survived for centuries and surviving earth quakes.   The Mars structures are not reinforced.  Fibers could easily be added.  Basalt was one of the materials mentioned as well as plastic brought to Mars.  Basalt fibers and plastic fibers are both used in concrete to keep cracks small and not growing.  Then a person could insert short metal reinforcement into the concrete so long as the nozzle doesn't hit it when the next layer is added.  The plastic and metal could be taken from scrap material.  The parachute and other landing components are scrap.

Reinforcement is easy to do.  Here is the DIY possible table design which is the size more typical of a machine out of concrete.     The majority of information is for building and bridges.  Civil engineering but it works just as well for smallers structures.


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## WmRMeyers (Oct 5, 2020)

TSutrina said:


> Concrete bridge port milling machine has been built as other big commercial machines.  Concrete is typically made with epoxy replacing concrete. Machine Casting – Castinite However actual concrete machines were build during WWII to produce production parts.  The base line is patent 1154155 by L. I. Yeomans  Sept. 1915  Articles on the web can be found.
> The Multimachine Open Source Concrete Lathe Project is a standard concrete machine found on the web.  Sorry do not know the full site address: ...
> 
> SNIP!




The MultiMachine group is on Groups.io, now.   multimachine groups.io Group There are files and photos there of the machines Pat and others have built. I'm a member and moderator there. No cost to join, and not much activity at all these days. It would be nice to have some new members!

Bill in OKC


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## ajoeiam (Oct 6, 2020)

TSutrina said:


> I fixed the top of a brick chimney also.  Snow, ice, and rain destroyed the concrete holding the bricks together.  Took it down to the roof and then rebuild it up.  There was not reinforcement in the chimney thus any side forces would put the chimney in tension, break the bond to the bricks.   The shape of the Mars structures is to use gravity to keep the concrete in compression.  All the Roman stone and concrete structures are design to put the concrete in compression since their is no reinforcement.  The majority even in the earth quake prone Italy have survived for centuries and surviving earth quakes.   The Mars structures are not reinforced.  Fibers could easily be added.  Basalt was one of the materials mentioned as well as plastic brought to Mars.  Basalt fibers and plastic fibers are both used in concrete to keep cracks small and not growing.  Then a person could insert short metal reinforcement into the concrete so long as the nozzle doesn't hit it when the next layer is added.  The plastic and metal could be taken from scrap material.  The parachute and other landing components are scrap.
> 
> Reinforcement is easy to do.  Here is the DIY possible table design which is the size more typical of a machine out of concrete.     The majority of information is for building and bridges.  Civil engineering but it works just as well for smallers structures.




The stuff holding the bricks together is not actually concrete. 
The technical term is 'mortar'.
It is similar to concrete but not the same thing.


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## Wizard69 (Dec 28, 2020)

I'm not sure how the original posters build went but hope that he has had some success.    I entered the machine too rebuilding industry real early in my career and then moved to automation.   In any event that early fist exposure to all sorts of lathes and mills made me think seriously about a DIY build.    That was years ago and frankly time and maybe more importantly money never materialized in a way to allow me to do such a build.    I look at such a build as a potetnially "fun" project.

There are issues however that can causes serious problems.   For one you need superior stiffness even in a small machine to get good results in metal.   It is pretty popular to build routers and even there guys struggle to get enough stiffness to get good results you would suffer even more trying to get good results in steel or other hard to machine materials.   In a nut shell it would certainly help to have some machine tools to start with to make building robust structures easily.    In any event one of the best book series on DIY machine tools was written by Dave Gingery, worth a look if DIY is in somebodies future.   

There is a lot of negativiity about DIY machine builds but we are on a forum where guys build engines so I'm not sure if anyone here really has a cause ot complain.    As a builder you just need to understand what you are getting into.    There is also the possibility of reworking commercially made stuff so don't leave that out.


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## MrMetric (Dec 28, 2020)

LOL... You are right on all fronts.... Fun to make, hard to make stiff, lots of negativity.... and, in this forum, most people will bend over backwards to say, "that is awesome", "good job", "wow... looks really nice... congratulations!"  It is the reinforcement that counteracts the rolling of eyes typically provided by our spouses!


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## SmithDoor (Dec 29, 2020)

Looks great 

Dave 



threesixesinarow said:


> It might be a little less impractical to make something that would be difficult to buy, either because it’s rare, expensive, or has never existed before - S_J_H’s boring mill, and Jackary’s ‘Stepperhead’ are great examples:
> 
> Cnczone boring mill build thread
> 
> ...


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## goldstar31 (Dec 29, 2020)

For those who want something  a bit different the Murad Bormilathe  was available. The wrote up is in Lathes.co.uk.
As A DIY alternative, I was always interested in a New Zealand design in a book called Improvements and Accessories for your Lathe with the author J.A Radford.
He called the two items-- Elevating Heads.
For those who want other things, there are delights in  and Indexing Attachment for the Lathe and a Worm Wheel Hobbing Tool.  Jack is a really different read.


In the Golden 'oldies' lathe variants, I've I've just bought a homemade 'Potts' Vertical slide with a  Myford nose and No2 MT arbour and a 9 hole division plate.

Again, Lathes.co.uk has  a section on  the numerous variants.  According to Christmas greetings, JCSteam has one which he was given.
Mine was obviously made from castings and drawings  from G P Potts and intially sold by Woking Precision Models who lived under the Forth Road Bridge , North of Edinburgh.  It was there that I  bought the casting for the Edgar T Westbury  Mill Drill which I made up from castings dropped by students at Gateshead Technical College. Later there were improvements known as the  Dore Westbury. Continuing the them, Dore Engineering was owned by an Arnold Throp who wrote his Vertical Milling in the Home Workshop. This involves a mention  of the Amolco  milling attachment and JCSteam seems to have one of these too. He's busy playing with a  Hornby train set which he claims is 'for his young son'   Believe that if you will.
Just a few bits and pieces to add to a thoroughly interesting post.


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## goldstar31 (Dec 29, 2020)

I've just spied a U Tube presentation for the Potts Milling Spindle. Neither are really like my version but nevertheless very interesting. Worth looking at

Best Wishes to all for a better New Year

Norman


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## TSutrina (Dec 29, 2020)

I just viewed the Potts Milling attachment for a lathe mounted to the cross slide.   I have a desk Rong Fu RF40 milling machine with a vertical round column like the Potts mill.  This means that you can not raise the mill spindle while cutting with the Potts device which limits my use of the mill.  If I have to raise the head on the RF40 I have the same problem of loosing alignment due to rotation around the column can not be prevented. 

But this article is focused on building a milling machine not using a milling machine  or a lathe milling machine attachment.   Stiffness  and vibration caused motion are the keys to any cutting machine including a router.    The gantry style routers all place the cutter off the center of the supporting beam thus cutting forces in any of the three primary directions cause motion in two and likely all 6 degrees of motion, 3 Cartesian directions and rotation in each.   Not one of the present gantry approaches places the spindle between two beams or a U channel at the center of the cross section.  This eliminates some of the multiple direction deflections, the beam torsional stiffness can be reduced and thus weight. 

I think the Maslow router for cutting into a basically flat surface is the most cost efficient and deals with the forces issue the most creatively.  It uses the flat surface of the work to locate the face of the router base plate and weight to provide counter torque and a third  force for moving in the plain of the work surface. 

I have though this a a starting point and by flipping it over and provide a flat surface reference for the router.  Vacuum suction and liquid film bearing to hold the router or spindle against the reference with a significant force so weight can be less.   The travel of the spindle is the limit of depth possible unless the motor can fit into a cavity already cut  while cutting further.  And a large flat surface is a problem to create and maintain.  Nothing is easy.


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## hanermo3 (Dec 29, 2020)

I´m possibly the worlds leading expert on "building a milling machine" ...
having spent around 18000 hours and about 16 years at it, mostly near full time.
My current gear is worth about 100.000 € as insurance replacement value, and for about the 12th time "I´m real close now..".
Grin.

The current version is a full on industrial VMC with a huge volumetric work area, 500 mm vertical  travel, 1600 table, 1000 x 500 mm travel, ISO30 spindle.
And the current problem is making a new servo motor mount, because the current AC servo is too small (400 W 1.27 Nm) to move the bridge up/down more than 3 secs, as it uses servo "peak current" rather than rated current.

The bridge is about 500 kg in mass - 2 pneumatic lifters one on each end help reduce the load on the screw.

Building a *good* milling machine is quite hard to do.
Imo.
Ime.

Should have built a smaller one, but now that it´s about running ...
I have commercial uses for it, like making lots of small accurate widgets in one run, like 200-400 at once.


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