[bjones]

yes the smaller round column has the footprint i think you need but is heavier duty than the x2, many people start out with these and usually keep them after getting something else to cnc because they make great drill presses too. if you choose to cnc a retrofit later the round column can help with that too. cncing it can also be an option later, there are many builds here or as you mentioned getting a skyfire or tormach. look on craigs list if you don't want to spend retail, some good deals can be found.

[NewHobby]

Ok well..... I find it very difficult to find fault or issue with your suggestion. It is quite good. Worst case it become a drill press which I would need with a smaller CNC. I "could" also get the LMS solid column and retrofit it on to that base ala asammons link below or just but a dang skyfire to compliment it. Either way your suggestion is sound and given my needs and parameters that is not a bad place to start, and I'd have time to think. Sold my box retailer bench top drill press so I actually need one now unrelated to CNC.

asammons franken mill. http://www.cnczone.com/forums/bencht...t_44991_a.html

Thank you again and I appreciate your time and opinion all of you.

[handlewanker]

handlewanker, not disparaging all Chinese mills, this is why I specifically mentioned Grizzly and their variants by other names I. I know Tormach and Skyfire are Chinese, but those are not grizzly "variants" by other names. I know what those are and what they are not and why low cost mills are the way they are. For the price you are sacrificing something of course.

Anyhow any chance you'll stick a spacer under the column of the Skyfire?

Hi, no way would I even contemplate putting a spacer under the column.......but that does not mean I wouldn't like more Z travel specifically for the same reasons you stated..........getting drills and chucks out etc.

The SMV-0 is a different kettle of fish than the other mills, being already totally CNC, so what I thought about was to extend the Z travel by fitting longer rails and a bracket at the top of the column to enable a longer ball screw to be fitted.

This retrofit for more Z is not rocket science or surgery, as it entails just replacing the existing rails for slightly longer ones.......the existing ones already extend beyond the top of the column and making a bracket to mount the stepper motor and add support to the back of the rails where they go beyond the top of the casting.

This will give 100mm more Z travel and as it's within the design envelope of the whole mill it will not affect the overall scale of the mill.

At the very top you wouldn't want to be doing any machining as such so extending the rails would not put any strain on them, but the extra travel for tool maintenance etc would come in handy and the bracket is a simple welded affair easy to do...........just have to wait and see if it's really necessary.

I don't like the idea of a spacer as it's down where the column is bolted to the base and that is where you need to have the most integrity for rigidity.....that is my opinion for what it's worth, but there's no other way you could have more Z travel without a spacer on the other column mills like the X2 etc, due to them having dovetail ways which cannot be extended above the column top.

The previous post with the video about the Continental guy and the BF30 bolted to the wall was a good way to eliminate most of the column problems, and if a spacer was on the cards for the X2 I'd think that the bracket would also help a lot too.

Going to another option X2 wise, and I would have to think about the possibility of adding a dummy extension to the top of the column complete with dovetails and stepper motor mount.......the stepper motor has to be mounted at the top with a bracket anyway so it may as well be a block of aluminium with dovetails just to allow the head to move off the column and still be in line with the column dovetails.....there being no machining done at the very top as it's only to get the height etc.

The top of the column being a rough un-machined casting would need to be machined flat to accept the extension.
Ian.

[NewHobby]

Very good, thanks!

[NewHobby]

Alright, need a project don't want to wait, size is an issue thus I bought the LMS Solid mill and and additional $1500 or so in tooling thus far from various sources, as well parts for oilier and powered draw bars etc etc..

I will definitely be doing a spacer under Z. I've read and looked LOT and a small plate here and there helps for bracing but I have BRACING plans. The first trick is how do you have a bunch of metal off it and tighten it down without pulling it out of tram. Second requirement is how to do it without extending the depth of the mill too much. Third requirement is it has to be removable like a slide on jig. This aspect will be WAY over engineered. We'll see what I have planned there and if it works out.

Won't bother posting endless pages of me scraping and lapping, I'll post when I make progress as it were but in another thread.

[handlewanker]

Hi, best of luck, sounds like you're going to be pretty busy......it certainly does pay to devote time to a project to mget it right.
Ian.

[NewHobby]

Indeed.... Thanks for the tips and advice!

[mduckett]

Congrats on the new machine and tooling. Wish they had the solid column when I bought mine. Looking forward to seeing your build. --md

[NewHobby]

So thus far my base, saddle and table is less within .0005. Got about 30 hours of scraping in it. It was pretty far off relative side to side especially. One way would be higher and sloped differently. Don't know how people lap, it does almost nothing when I do it. When I get it all back together however the X Axis one one half is effectively 0 travel the .0005 indicator needle flickers a bit but it never hits the first increment then half way across the table travel it gets high sloping from 0 to .0035 over 6 inches. I suppose despite things being really square and level independently something is going on I"ll have to work out figure out. I took it all apart and all the parts are square and true and level. Odd. I'll figure it out. Then on the the x axis which is easy. Then I'll make new gibs out of brass.

Anyhow made manifold for an oilier but I have to remake it to clear the trick spickets I got for it to control flow. 1/2 the enclosure table is made as well. Got parts for the power draw bar too.

I will most definitely be putting a 2" spacer under the column and adding a brace. Frankly when you shim the column combined with the limited flatness of it the column is likely floating with just a few touch points. I'll be lapping my mount areas but with shims it really affects the contact area. I milled some steel and it shudders quite a bit when conventional milling. I did use a crappy Chinese bit though. Anyhow need a brace at least how I see it other may see differently and that is quite fine. Mine is getting braced.

I suppose 2 years of metalworking and fabricating make me look at column bracing issue just a bit different. The base plate the whole mill including the column brace sits on is a 2 foot by 9 inch 3/4 inch thick plate. When welded and thru bolted with backing plate on both sides of the column and base foot it will not be moving a lot.

Speak peek, checking for general fit. Need to make a few tiny tweaks then I'll be welding it up. Those holes in the bottom foot you see are for 1/2" grade 8 bolts that mate it to the 3/4 plate. Awwww look at the cute little column it comes with in the background ...

[NewHobby]

Found the problem. I scraped the table ways flat while it was laying face down on the marble. Well turns out the table surface is not that level. Unfortunately I scraped the ways flat so now that it is on the waggle with the gibs I Need to redo it and based on the saddles flatness. Lots of work. One side is now .0005 across the entire x travel the other side is still in progress. 8 more hours or so, sucky part is I have to take table on and off take out and out in gibs over and over. Painstaking. Ohh once I get the table flat again them I have to take down an entire side to level the y and then correct that sides x again. Fun......

[handlewanker]

Hi, I know how you feel, I once had to hand plane .013" off of three Vee slides and two flat ways, top and bottom to get the saddle of a lathe to fit properly.

The lathe was a 1920/30 Colchester Bantam and had seen many years of work hence the .013" wear in the ways which was mainly down at the chuck end.

It took me about 2 weeks evening work to plane the bed then 4 evenings to scrape the lot in again.

At the outset you have to have a target that you intend to achieve and that is what drives you on to get there.

If you know what you're doing the end is just a few hours labour.

The other side of the coin is building a house to spend just one night in........you have to have the end plan to decide if the amount of work is justified as opposed to buying outright a commercially made job.......cutting your losses also comes into the picture.

As a matter of interest what made you decide to go for an X2 and retrofit it?
Ian.

[NewHobby]

I wanted to work on something as a project, unfortunately this will not take that long. I wanted and still do want to do some manual milling first. Skyfire was 3 months out still. I wanted more z than the skyfire has and as mentioned a spacer with a column brace is no problem when doing a retrofit. Tolerances are so whacked out and loose on these small mills despite bjones whacked out rumblings to the contrary, maybe he has far lower expectations than I do, anyhow they have to be taken down and rebuilt anyhow so some fab work to lift the column is no biggie. I would not do it with a commercial properly tuned cnc.

I suppose in the end I want to do a project and this mill was the right size. Cost was not an issue in the end this will cost 50% more than a sky fire. He'll that steel and water jetting for the column brace and base plate will most definitely cost more than the mill does. The steel alone was. Still got more parts to make for it the the base has x any x adjustability so it does not pull the column then I have to take it to get surfaced flat since heat distorts metal.

My table will be as roughly .00002 level what done I'll post video when done. Frankly it is not hard just time consuming. My carbide scrapers are getting dull.

[bjones]

Tolerances are so whacked out and loose on these small mills despite bjones whacked out rumblings to the contrary, maybe he has far lower expectations than I do, anyhow they have to be taken down and rebuilt anyhow so some fab work to lift the column is no biggie. I would not do it with a commercial properly tuned cnc.

man you are whacked, i warned you that the siegs are worse than the bf20 types contrary to what you were claiming having no experience at all. glad to see that you have proven me correct and are having to do far more work than if you'd have listened to me in the first place. funny how you read a couple bad posts about bf20's and decided they all must be that way even though others chimed in to the contrary but couldn't believe any negative posts about the x2. welcome to a good dose of reality, it does bite. LOL

I suppose in the end I want to do a project and this mill was the right size. Cost was not an issue in the end this will cost 50% more than a sky fire. He'll that steel and water jetting for the column brace and base plate will most definitely cost more than the mill does. The steel alone was. Still got more parts to make for it the the base has x any x adjustability so it does not pull the column then I have to take it to get surfaced flat since heat distorts metal.

Don't forget you'll also have to have that weldment stress relieved otherwise warping over time will make all your work pointless. more money to throw at this.

[handlewanker]

Hi, for what it's worth, I think the bogey of welded structures is very over rated in that it appears that if you weld something then it walks around as it twists and bends......for some reason.

I worked in the industry making linear transfer machines for the car industry......they are long machines that have, in the one I worked on, 21 stations, each station doing a separate operation....total machining time for the job passing through the machine is determined by the slowest station operation, which in this case was the inlet manifold for a Holden 4 cylinder engine......40 seconds.....a raw aluminium casting is robotically loaded and unloaded in 40 seconds totally finished machined.

The various stations were ALL built up from welded plate material and aligned separately in the manufacturing facility.

These machines run for several years and I don't think they have weldment distortion problems during that time.

When a structure is welded it DOES get stresses locked in, but they only become apparent when you subsequently machine chunks out of the structure and the contained stresses pull the frame out of wack.

The worst you can do is to clamp a welded structure and twist it before machining.

It is advised after welding a structure to mill all surfaces that require to be connected accurately with another part.

Provided you don't remove significant amounts of material then distortion is not a problem.

Therefore, when you proceed to machine a welded structure, use packing material under the points that sit on the table to keep the structure in it's finished welded state, then you can machine it without the frame twisting back after the clamps are released.

Practically all the distortion I've seen in welded structures is caused by incorrect clamping prior to machining.

On the subject of the X2, it's not a bad mill as mills go, made down to a price etc, but it does give you a basis to start with when you want to improve it by extra work and fitting........the extra cost is minimal if no new parts are added.....labour is only a figure for accountants to worry about when you are being paid to do the work.

I think I could state correctly that if the dovetail slides are not accurate in their surfaces then it probably was so when the castings were machined and the finished machine part was released from the clamping forces.

If you have to apply manual alignment for setting up a casting on a machine prior to machining the raw casting, as opposed to just putting it into a jig and clamping it wherever it sat, then the cost would double if not more.......and I think most if not all of the time the person doing the machining will be an operator who just loads the part to a jig and presses the green button whatever may be the state it gets clamped in.

This is OK for an economical machining cost factor, but totally hopeless if you want to have a precision machine that is good to go from the box, but it's a good starting point as long as the initial purchase is cheap.

You wouldn't want to take a precision manual mill that cost 2 or 3 times a much because it was precision, and then hack it about to retrofit it for some CNC purpose.
Ian.

[NewHobby]

man you are whacked, i warned you that the siegs are worse than the bf20 types contrary to what you were claiming having no experience at all. glad to see that you have proven me correct and are having to do far more work than if you'd have listened to me in the first place. funny how you read a couple bad posts about bf20's and decided they all must be that way even though others chimed in to the contrary but couldn't believe any negative posts about the x2. welcome to a good dose of reality, it does bite. LOL



Don't forget you'll also have to have that weldment stress relieved otherwise warping over time will make all your work pointless. more money to throw at this.

I am well aware of the metal quality difference between the Sieg ans Weiss. Thus far I am having all kinds of fun and that thin column on the BF would be getting braced the same maybe even more. Infact I bet the column on this SX2 is thicker than the BF20. It is 1/2 thick. I knew EXACTLY what I was getting with the SX2, frankly it was better than I thought. Actually the SX2 column does not ned bracing, I was kind of disapointed. I am doing it beacsue I like building. I tis not needed it is wanted.

I went along qwith you to shut you up. Seems like being polite does not work.
I have way more experience and knowlege that you think.

[NewHobby]

Hi, for what it's worth, I think the bogey of welded structures is very over rated in that it appears that if you weld something then it walks around as it twists and bends......for some reason.

I worked in the industry making linear transfer machines for the car industry......they are long machines that have, in the one I worked on, 21 stations, each station doing a separate operation....total machining time for the job passing through the machine is determined by the slowest station operation, which in this case was the inlet manifold for a Holden 4 cylinder engine......40 seconds.....a raw aluminium casting is robotically loaded and unloaded in 40 seconds totally finished machined.

The various stations were ALL built up from welded plate material and aligned separately in the manufacturing facility.

These machines run for several years and I don't think they have weldment distortion problems during that time.

When a structure is welded it DOES get stresses locked in, but they only become apparent when you subsequently machine chunks out of the structure and the contained stresses pull the frame out of wack.

The worst you can do is to clamp a welded structure and twist it before machining.

It is advised after welding a structure to mill all surfaces that require to be connected accurately with another part.

Provided you don't remove significant amounts of material then distortion is not a problem.

Therefore, when you proceed to machine a welded structure, use packing material under the points that sit on the table to keep the structure in it's finished welded state, then you can machine it without the frame twisting back after the clamps are released.

Practically all the distortion I've seen in welded structures is caused by incorrect clamping prior to machining.

On the subject of the X2, it's not a bad mill as mills go, made down to a price etc, but it does give you a basis to start with when you want to improve it by extra work and fitting........the extra cost is minimal if no new parts are added.....labour is only a figure for accountants to worry about when you are being paid to do the work.

I think I could state correctly that if the dovetail slides are not accurate in their surfaces then it probably was so when the castings were machined and the finished machine part was released from the clamping forces.

If you have to apply manual alignment for setting up a casting on a machine prior to machining the raw casting, as opposed to just putting it into a jig and clamping it wherever it sat, then the cost would double if not more.......and I think most if not all of the time the person doing the machining will be an operator who just loads the part to a jig and presses the green button whatever may be the state it gets clamped in.

This is OK for an economical machining cost factor, but totally hopeless if you want to have a precision machine that is good to go from the box, but it's a good starting point as long as the initial purchase is cheap.

You wouldn't want to take a precision manual mill that cost 2 or 3 times a much because it was precision, and then hack it about to retrofit it for some CNC purpose.
Ian.

In this case, the brace the facing plate the the column will be getting surfaced level, heat of welding, especially MIG welding distport metal complelty undetstood. A rough estiamte is 5 thousandths or so need to be taken off to surface it frat psot welding. The 1/2 plate whith me welding at 3/8 power relly held up well actually. I could have used tigg but this is such a tericila applicaion with aalmost zero stress all it does is aid in head tippind or twisting. Ever so slight a twist I got after the welds. Only so much you can do with C clamps for a ne off project. I planned on surfacing it. I do have an oven that is used to stree relieve Chromoloy suspension and what not I can stess relive the brace as well but frankly is is simply not needed in this type of applicaion. I'll surface it and call it good.

Actually yes the SX2 is better than I hoped I was pleased with it. Definitly room for improvment like all of them. I decided to order another table and use the current one to practice some random techniques to see thier cause and effect. A big part if the journey for me so ti s all great fun trying to levelt hign thing. I am really enjoting the frustration of it all.

The dove tails are an off 56 degreesn and all of the gods make contact at one thins part of the gin, hte gids are scoed liek someone drew a lin on them. Pretty typical seent his with 0704 and waht not. I will be making new gibs as well using oil impregnated brass when it get is all scraped and I can then memasure the size needed. The ways will be oiled with one shot oiler.

[ger21]

It's funny, the member's here who report the most posts, are constantly reporting each other. Which means that they themselves are the problem members here.
If I have to delete more posts, I'm going to ban with no questions asked.

[jdrew1]

WOW, I'm always surprised at the vitriol directed at people who try to solve problems in ways not considered "proper" or "traditional". I came here so many years ago in search of quality info to improve my X2, but I hardly ever come back this way because every other thread seems to disintegrate into personal insults and shaming now. I don't want to spend my limited forum time sifting through flame wars to find the good stuff. There exist other forums where the friendly dissemination of knowledge is encouraged. NewHobby, check your PMs.

BTW, thanks ger21 for trying to keep things somewhat civil.

Drew

[NewHobby]

It's funny, the member's here who report the most posts, are constantly reporting each other. Which means that they themselves are the problem members here.
If I have to delete more posts, I'm going to ban with no questions asked.

Wow this explains why we have trolls out here. I'm out.

[NewHobby]

It's funny, the member's here who report the most posts, are constantly reporting each other. Which means that they themselves are the problem members here.
If I have to delete more posts, I'm going to ban with no questions asked.

Ahh OK, well this explains a lot about this site. Ok I will just ignore stuff and let it go on. I'm good.