Simple skate bearing design. Will it work?

[bdahmet]

Hi everyone, I have attached some drawings of my idea of a simple skate bearing slide design. It consists of 2 5mm thick Aluminum plates that are machined from one side only. just some holes and 2 different depth channels.
The Skate bearings are squeezed inbetween the plates the channels are slightly smaller than the diameter of the pin of the skate bearings and centers the pin when bolted together. The bolts on the upper side allow for pretensioning the upper bearing.

Do you think that it will work?

[vlmarshall]

Instead of clamping the plates together and tapping the two split holes, why don't you add two pockets for captive nuts?

[teamtexas]

I like it! You could cut some out of foam if you have access to a cnc router. Then use the foam in a lost foam casting process to cast them out of aluminum.

Dan

[jalessi]

Looks good, kind of looks like a simplified version or spin on the link below:


http://www.buildyouridea.com/cnc/hbl...ototype_4.html

[bdahmet]

I actually was not intending to cut any threads. I think the aluminum plate and the sharp edges will serve as a bas for the bolts thread to bite itself in.
So with cast aluminium I think it would be too brittle.
Tha Idea was to being able to have it machined in a simple machine shop.

[bdahmet]

Originally Posted by vlmarshall Instead of clamping the plates together and tapping the two split holes, why don't you add two pockets for captive nuts?

Good Idea....

[LeeWay]

It looks good. Pretty easy mounts to make. The only issue I have with the design isn't in the design of this part at all, but in using unsupported rod.
I would only consider that on a Z axis or a very small machine. These rods will have flex. Back and forth especially toward the center of the cutting area.
Just not a rigid design from the getgo.
Many guys do build this way though.
I did a little testing before my first build and the amount of flex in a 4 foot rod was just unacceptable to me. I needed more precision than that. Once built, there is no fixing the flex unless you cam either live with it or redesign it.

A much more rigid idea is flat bar or tube. Still not perfectly accurate. I did a combination of those and my rails are very stout. I get very nice accuracy now on my router. I used a very simple bearing design using 1/8" by 3/4" aluminum tube.
I would say the cost was on par with your design with nice round rod.

[bdahmet]

The design can be changed to support support rails I think...

[cnc2]

Hi guys !

I've been inspired by the design shown by Jalessi a few posts before.

I'm a beginner non machinist & don't know how to use Solidworks yet (i'm having trouble with my graphics).

You can see my idea in the drawing below it's a very basic/crappy MS Paint drawing... i hope you'll understand !

I want to make the bearings of the right side adjustable by excentric for preload but will have to mod the design a bit...Any help ?

I don't know the effect of hardned steel bearings rolling on an iron dovetail, i'm thinking to use grey iron machined from solid. What do you think ?
How much will it cost in a basic machine shop ? (aprox price or expensive/lowcost or hours of work)

I want to build a cnc knee mill the size of an X2/X3 and use this design for XYZ, the mill will be cast aluminium. What do you think ?

The cool thing about this design is that you can lengthen/shorten it to suite your needs, IMHO.


Any input is much apreciated.

Thanks !

cnc2.

[Oldmanandhistoy]

Hi Bdahmet,

Nice idea but I would like it more if the two plates were thicker so they would clamp tight together.

John

[bdahmet]

Originally Posted by Oldmanandhistoy Hi Bdahmet, Nice idea but I would like it more if the two plates were thicker so they would clamp tight together. John

Actually I need the distance so the Bearings are centered and hold in place, if they clamped together the bearings would be loose..

This way I autumatically center and fix them...

[cnc2]

Originally Posted by bdahmet Actually I need the distance so the Bearings are centered and hold in place, if they clamped together the bearings would be loose.. This way I autumatically center and fix them...

I think it should work for a wood router for X&Y but you'll need two of them on each side of the X &Y; for Z i think it will take too much space & require four of them.

Try to design the whole router in solidworks, it will give you a better idea.

Thanks !

cnc2.