Anybody got any experience building a router using these wheels. Please tell me how it worked out and show some pics if you can.

Thanks
Walt

This one here used them. Unfortunately, all the pics in the thread are gone.
http://www.cnczone.com/forums/showthread.php?t=33124

http://ww.mechmate.com

http://www.cnczone.com/gallery/showphoto.php/photo/114

http://www.cnczone.com/gallery/showphoto.php/photo/232

.

http://www.cnczone.com/forums/showthread.php?t=24582&highlight=wcarrothers1

Don't know if these are the type of V wheels you are thinking about how ever I can say they work well on my machine

b.

Yeah those are the ones, what do you guys think of this for x and y made out of MDF and Angle iron.

While I believe the ones I have are dual row bearings I would not consider them lateral contact races. By that I mean loading them sideways the way you are may not exactly be the direction they have the most support. having the load to their shaft is the way they are suposed to ride far as I know. They might have a chart you can figure out what their vertical vs sideways loads are rated at.

I would not do it like that my self.. I'd make them ride as I did.

b.

Also the larger ones like I used are not all that cheep (depending on how lucky you get getting them) so keep in mind they add up (cost wise) quick...

b.

How do you mount a spindle to that?

I do like the horizontal rail idea, though. I may incorporate that for the X rails on the machine I'm designing. Looking at the BWC catalog, it looks like as you widen the rails (from angle to angle), the axial load decreases, if the load is in the center. After some quick math, it looks like as you double the width, the axial load decreases by half. The #2 size rollers are rated at 140lbs axial load.
Based on the formulas I see in the catalog, a 200lb load gantry, with the load centered on the carriage, with the rollers axles at 4" OC (2-5/8" across the points of the angles), would give an axial loading of about 38lbs/wheel. Well below the 140lb rating.

Unfortunately, where the loads are actually coming from during motion is a bit more tricky to figure out, and not so simple. And feel free to check my math. Download the catalog at www.bwc.com

So what would you do different to make it a viable idea? As far as mounting the z I would mount it to the carriage on the y axis.

I am not done with the drawing, I was just playing around today and came up with that. The best way to mount the z might be to turn the y on its side and build a torsion box. I am no engineer, Just want to build a nice router and looking for ideas.

Thanks
Walt

I know not the best drawing but how bout something like this? you could use rollers on both the top and front to keep the z from any movement.

Walt

Sir,

Attached are some pix of my Z axis usiing vee wheels. We used vee wheels and hardened ways for X and Y axes of one of our smaller machines (production work) and they did well.

Regards,
Jack C.

I still think making the X bearings ride on their side like that is not the best idea becides it makes the machine much wider then it would otherwise have to be if they were upright.

Course after thinking about it you can say that yours are now taking the lateral loads that the router will put on them when running and just have to carry the weight sideways.

Course in my design I was going to put 3 bearings in (one above and one below as I currently have then another faceing 90deg to those on the rail to deal with the lateral loads. How ever I never put them in because it would have made things more complex especially while trying to adjust height and calibrate the machine then I though it would need to be and I don't think at this point it would have been better with them.

b.

b.

What do you think of this. Uses DualVee's the y axis carriage will use 2 vee rollers at the top back and 2 on the front bottom, with z mounted to it.

Walt

Walt,

I like this design for the X-axis much better. Agreeing with many of the people here, the dual Vee's are designed to carry the load through the axis. Of course the wheels can sustain a certain amount of lateral load which will vary depending on their rating.

The wheels would probably not fail under these loads. However, the axles and the structure supporting them would be under constant stress from the moment (torque) that the lateral loads would cause.

This could deform the inner raceways of the V-wheels or something else which could cause slop in the system over time.

I am still unsure of what you mean by the Y-axis design. Also just curious, what is you major reason for using V-wheels? Not that thats a bad thing, just curious.

Keep up the good work, its getting there!

I think you might get some flex, due to the slot that the nut goes through. It would be better if the rails were solid.

I think you might get some flex, due to the slot that the nut goes through. It would be better if the rails were solid.

Walt,
This is true solid is always better. If you give me the dimensions, material, and an estimated gantry weight, I can stress it for you and quickly tell you how much "flex" or deformation you will encounter.

That goes for any of you!

Well, the reason for the DualVee wheels, I dont really have one. I have been trying to come up with a router that I can build with my existing tools that I have at home(tablesaw, router, CNC'd Minimill. I have looked at Joe's and it looks great but I haven't had any success building accurate parts with my home tools. The minimill travel is just to small. So I am just trying to come up with something that can be built easily and still be accurate enough to build something better. Does that make any sense at all? The DualVees looked like they would work fairly well and they still would not cost as much as buying linear rails etc.

Maybe I am barking up the wrong tree though, I am open to suggestions.

Your input is greatly appreciated!!

Walt

Walt,

I wasn't trying to imply that you are "barking up the wrong tree", I was just curious.

What is the overall size of the machine you are wanting build and what kinds of tolerences (accuracy and precision) are you wanting?

There more designs and more experience with home brew linear motion systems using "skate" bearings and angle aluminum and/or tubes. Many of them only require you to cut square pieces and no odd shapes. I can post some on my website or email them too you.

Again, I am not trying to drive you away from your design at all. I have only used V-wheels in 2 machines and do not have the same amount of experience as other designs.

I will keep my eyes peeled though and if I see any machines using them I will be sure to let you know.


Regards

I would like to have about a 36x24 cutting area, as far as accuracy goes, of course it can never be accurate enough. I just want a reasonable amount of accuracy without spending a lot of money. I did not take it that you where trying to talk me out of the DualVee's. I am opened minded and am not ruling anything out at this point. Just doing a lot of exploring my options.

Any plans that you have would be great!

Walt

I have only used V-wheels in 2 machines and do not have the same amount of experience as other designs.

I will keep my eyes peeled though and if I see any machines using them I will be sure to let you know.


Regards

ShopBots have used them for years, and the Mechmate uses them as well.
www.mechmate.com

I'm currently designing a machine to use the Dual V's. They're much stronger the rollerblade bearings, and much cheaper than linear rails.

ger21,

As I stated, I ( me personally) do not have as much experience with V-wheels as I do other designs.

I am also aware of shopbot and mechmate. However, I believe they do not run their v-wheel on stock angle iron (could be wrong). I think they now use a machined surface steal angle and then actual tracks designed for these wheels called track rollers. They also use them in the upright position as per their designed use.

I was in no way implying that the design would not work.

A linear motion systems "stregnth" is determined by all components and not one. The v-wheels themselves are indeed stronger than skate bearings since they are made for this type of application.

However, if I had a choice between skate bearing running on hardened precision rod or V-wheels running on aluminum angle stock then I would go with the skate bearing setup.

I have built 2 CNC routers that use V-Groove Wheels on the X-axis alone, using the mill surface angle steel that you can purchase from Mcmaster part number 9017K44. Which is still cheaper than alternatives by the way. It works well and I would prefer that to skate bearings for that orientation.

But for the Y-axis using only 2 rails with the V-groove wheels, I am still unsure because of the lateral loads.

ShopBot uses the size 2 wheel. For years they used them on "soft" rails and there was some rail wear. Now they use the size two wheel on stainless steel I believe.

For the MechMate, I recognized that the size 2 wheel was too small, and ploughing into the narrow edge of the SB rail. So I went to size 3 and widened the rail. Excellent results.

The folk at MechMate wanted the option of using hardened rails, so this (http://www.mechmate.com/forums/showthread.php?t=21) was made available. (See last pic in thread 5-Oct.)

But the folk have now warmed (YouTube) (http://www.youtube.com/watch?v=j0RN_C-iosU) to grinding a neat V-profile on top of angle iron. See these threads:
The JR Skate (http://www.mechmate.com/forums/showthread.php?t=19) was being brewed while I was looking at moving the rails over a grinder (http://www.mechmate.com/forums/showthread.php?t=440). Since we use lasered parts all over the MechMate, it made sense to include a lasered "skate" in the design. See here (http://www.mechmate.com/forums/showthread.php?t=479).

Anyway, to cut a long story short, the plan is coming together nicely for very economical rails, that are self-cleaning.

PS. Get the rollers from Rick at Superiorbearing.com :)

However, if I had a choice between skate bearing running on hardened precision rod or V-wheels running on aluminum angle stock then I would go with the skate bearing setup.


You can't run them on aluminum angle, it probably wouldn't last more than a few days. I plan on running mine on steel angle or SS angle.



But for the Y-axis using only 2 rails with the V-groove wheels, I am still unsure because of the lateral loads.



The #2 wheels are rated at 140lbs axial load. Using the formulas in their literature, I calculated that my ~75lb Z axis only places about 35lbs of axial force on the wheel. Even if you add 100lbs of cutting force (which is a lot if using a handheld router for a spindle), that load is carried by two wheels, so you only be at 85lbs axial force per wheel, which is only 60% of their rated capacity.

Kevin
If you would, I would take you up on your offer of e-mailing me those plans.

Thanks
Walt
wdp67@yahoo.com