[MechanoMan]

Anybody familiar with this guy's Kickstarter?

Aluminum V groove rails for cnc. Truly affordable at last. by brian h ? Kickstarter

He's got a website at:
v groove rail

And is vending on eBay.

So aluminum is nowhere near steel, esp for the type of harsh point-loading you get with v-bearings' small contact patch. That doesn't mean it won't work, and he DID go to the trouble of getting it hard-anodized which is fairly serious.

He acknowledges that these won't work with steel bearings, and to use Delrin, which makes sense in itself, but if you've got stiffness issues with a router then supporting through a small-contact area on Delrin raises questions with me.

I'm skeptical of his claims that you can just join smaller pieces into longer pieces. Well it's physically possible of course, I'm skeptical it's a good trouble-free solution.

[JerryBurks]

I can not answer your question directly but here my experience for an 8-foot extension table that I added to my machine (the machine itself uses 20mm linear supported bearings).

I did use 1.5"x1.5"x8' anodized aluminum angle as rail but instead of a v-grooved bearing I mounted a pair of small diameter skate wheels of very hard Polyurethane (99A hardness) at 90 degrees running on the aluminum. With a bit of preload that works very well and is precise. I did not use it very much yet and can not vouch for durability but I expect this to hold up well if cleaned regularly. These skate wheels have a very wide (about 17 mm) contact patch on the aluminum.

For the question of Delrin on aluminum I would expect this to work well for a light duty machine provided there is some reasonable contact surface.

[mactec54]

MechanoMan

This would be ok for a laser or 3D printer machine setup,(For very light work only) but not much good for much else, no matter what they say, there are others that have done a better job than this, long before this was done, most extrusion companys have been doing systems like this for years, & are a lot better than this but cost for it is high

If you want a cheap linear system the round supported rails work ok for a beginner machine

[kevincnc]

Yep, I was going to say it would work for a fast light duty machine, a PCB router at best. If they are cheap enough and you don't need much speed, it seems to me that solid sliders made out of Nyloil, UHMW, or acetal would be much more rigid than v-rollers.

[dertsap]

He acknowledges that these won't work with steel bearings, and to use Delrin, which makes sense in itself, but if you've got stiffness issues with a router then supporting through a small-contact area on Delrin raises questions with me.

.

delrin is quite tough and it would most likely work well for a wood router , but the delrin wouldn't be at all forgiving of other matter such as metal chips or hard grit which would get imbedded into the rollers . In my workshop it would be destroyed in no time .
steel v bearings are cheap and it's easy to make your own rails . I built a good sized table with v bearings , the y axis bearing run on angle iron , the x bearings run on steel square tubing . It plenty solid for wood , I've cut plenty of aluminum and even cut steel with the sears router that is mounted for a spindle . It was relatively cheap and won't be wearing out anytime soon if ever

[kevincnc]

delrin is quite tough and it would most likely work well for a wood router , but the delrin wouldn't be at all forgiving of other matter such as metal chips or hard grit which would get imbedded into the rollers . In my workshop it would be destroyed in no time .
steel v bearings are cheap and it's easy to make your own rails . I built a good sized table with v bearings , the y axis bearing run on angle iron , the x bearings run on steel square tubing . It plenty solid for wood , I've cut plenty of aluminum and even cut steel with the sears router that is mounted for a spindle . It was relatively cheap and won't be wearing out anytime soon if ever

The rails in question are only 3/16" wide, I'm guessing your setup is much more substantial.

[dertsap]

The rails in question are only 3/16" wide, I'm guessing your setup is much more substantial.

it definitely is . And that was more or less my point , those rails would probably work for a wood router that isn't run completely animal , but there are better options . The availability of rails , ballscrews and general cnc building equipment has shot thru the roof over the past few years . Mine was built before the flood of china stuff , it was butchered together on a tight budget , I love the v groove bearings on the crude rails , and I wouldn't change anything about it , except maybe a water cooled spindle and probably a few other things that I'll eventually dream up

[MechanoMan]

steel v bearings are cheap and it's easy to make your own rails

How would you make steel v-rails in significant lengths for a router?

I could see mounting them against a tilted block on a large mill, but the length I'd need would exceed the width of the mill by several times, making discontinuities likely where I have to remount and reindex.

[kevincnc]

How would you make steel v-rails in significant lengths for a router?

I could see mounting them against a tilted block on a large mill, but the length I'd need would exceed the width of the mill by several times, making discontinuities likely where I have to remount and reindex.

Square tubing is pretty accurate and comes in 20-24ft lengths.

[CarveOne]

How would you make steel v-rails in significant lengths for a router?

I could see mounting them against a tilted block on a large mill, but the length I'd need would exceed the width of the mill by several times, making discontinuities likely where I have to remount and reindex.

The MechMate Forum users have various ways to make them from cold rolled steel flat bar stock using mechanically guided angle grinders. I think there is a forum here that has discussions related to linear guides that may also have some info.

Two of my local friends successfully built a 5' x 10' MechMate using the home shop ground rails and V bearings.

[dertsap]

How would you make steel v-rails in significant lengths for a router?

I could see mounting them against a tilted block on a large mill, but the length I'd need would exceed the width of the mill by several times, making discontinuities likely where I have to remount and reindex.

As Carveone stated , lots of guys have had success grinding the rails , I didn't modify my rails at all , the v bearings ride the top of the angle without any problem what so ever , and they are pretty solid . When I built my machine I considered the fact that the rails may need to be machined , and at the time I worked on mills large enough to easily machine an angle to the 6 foot rails . But it works so well as it is that I never bothered

[vjeko]

dertsap, I sent you a private message as I'm interested in a few more details about your setup,
but I guess you haven't had time to see it,so I'll ask here anyway, probably others may be
interested in some more details.

Could you give some more info on the rails / bearings and a picture would be much appreciated.
One thing I was curious about was your comment on machining/grinding the rails - I presume you
are using ordinary mild steel angle -I would have thought the biggest problem would be that
it was soft compared to industry rails(I have read a lot of people using alu angle - that certainly
can't last long). I guess the v-bearings would outlive the rails, so only benefit of machining
would be to avoid run-in / the bearings doing the machining (or have I missed something ? )

I'm interested in making a manual driven x/y axis for drilling holes (both axis are to be 32mm indexed)
for furniture / rough planing wood and am looking for a cheap solution (igus quoted me 900 Euro )

I've been throwing all sorts of ideas in my mind but maybe someone has tried all this so I'm not re-inventing
the wheel or doing something which doesn't work too well:
- v-bearing on plate cut with cold saw (would like v-bearings mounted in horizontal plane
so I can drill holes in plate and index with indexing pin through the carriage)
- v-bearing on angle
- v-bearing on stainless round rod (just tack rod on each side of square steel tube eg 30mm*30mm*3mm))
- bearings (top & side) running on square steel tube)

[dertsap]

Sorry for not replying to your pm , I saw it and meant to reply but I've been swamped and haven't had much chance to stop lately . I used angle iron and v bearings , I also used v-bearings on square tubing which worked incredibly well . you can see some pics in my build thread http://www.cnczone.com/forums/diy_cn..._router-8.html
The pics in the thread are the last to be seen of the router , it's since been torn down to make room for my mills , it was a fun little butcher job though it's life was short

[vjeko]

No probs , time is scarce for everyone - thanks for replying ! Had a look at your build but maybe I missed
it - what size v-bearings /where did you buy them / what wall thickness is the tube/angle ?
I was thinking of 30mm*30mm*3mm for the tube - maybe even 25mm*25mm*2mm would be
good enough as the axis are manually moved - what do you think ?

Would you have any opinion based on your experience with v-bearings/steel tubes on
whether a horizontal plane mounting of the v-bearings may be workable since
it may make indexing easier (holes 32mm spacing in tube length/ indexing pin through carriage into holes) ?
(could put an indexing flat in the vertical plane - got to think out of the box )
One other alternative as I mentioned would be to use stainless rod - not sure how
good that would be eg tacked on two sides of a square tube.


Just curious - you mentioned scrapping the router to make room for your mills - did you
opt for cnc adapting industry milling machines instead ?

[dertsap]

No probs , time is scarce for everyone - thanks for replying ! Had a look at your build but maybe I missed
it - what size v-bearings /where did you buy them / what wall thickness is the tube/angle ?
I was thinking of 30mm*30mm*3mm for the tube - maybe even 25mm*25mm*2mm would be
good enough as the axis are manually moved - what do you think ?

Would you have any opinion based on your experience with v-bearings/steel tubes on
whether a horizontal plane mounting of the v-bearings may be workable since
it may make indexing easier (holes 32mm spacing in tube length/ indexing pin through carriage into holes) ?
(could put an indexing flat in the vertical plane - got to think out of the box )
One other alternative as I mentioned would be to use stainless rod - not sure how
good that would be eg tacked on two sides of a square tube.


Just curious - you mentioned scrapping the router to make room for your mills - did you
opt for cnc adapting industry milling machines instead ?

The router ate a lot of space which is why I tore it down , it's in a state that I could slam it together again in a day . I've got 2 x2 mills which run pretty heavy over the weekend , a g0704 which is waiting for parts , and my plan is to have at least 1-2 more of the 704's by the end of the year , industrial machines will be in a few years , maybe sooner depending upon how things go . wood was fun but metal is my thing
the tubing i used was 1 inch
my bearings are similar to what is in the link below , after paying 45 bucks for a 3 week delivery of a few bearings I refuse to post anything regarding the company that I bought them from (screw them) , these are the same thing .
I wouldn't recommend mounting your bearings horizontal , all your wear and force will be on one side of your rail

[vjeko]

much appreciated ! Now thinking cap on and off to the drawing board.