[Feist92]

Hi
Sorry if this is the wrong place but has any one tried machining a linear slide along these lines:




I have tried searching but i couldnt find anything similar to this. its for a small 3d printer i want to make with 12mm shafting. Im having some problem deciding how to machine the angles on my mill (no cnc) so any ideas would be appreciated

Regards
Jonathan

[Al_The_Man]

Is there nothing in the Pacific Bearing line you could use?
Linear Bearings, Linear Actuators, Linear Guides, Roller Bearings, Linear Motion Solutions
Al.

[Feist92]

Is there nothing in the Pacific Bearing line you could use?
Linear Bearings, Linear Actuators, Linear Guides, Roller Bearings, Linear Motion Solutions
Al.

There probably is but wheres the fun in that?
Im the type of person who is loathe to buy anything if i can make it (even if im not sure how atm :P)

[PaulRowntree]

Here is a fellow who built a backyard Al foundry and used sand/lost styrofoam to produce pieces like this. He has a well developed projects website.

Home-brewed linear bearings

Cheers!

[louieatienza]

Isn't that an LM76 jet rail truck?

[hub]

Just my opinion.. In theory that would work fine. But practically, I think it would not wok very well. Because there is only "preload" adjustment (on the eccentric roller). The other two would have to be machined very very precisely because they have no adjustment at all.
Hub

[Feist92]

Yea it is the jet rail system.
What do you think of this design? The bottom bearing will be adjustable

[wildwestpat]

Not sure about the effect of tolerances on your design of truck. The variations in the rail diameter need to be accommodated along with variations on OD of the bearings or the shaft holes. The use of a needle roller as the main bearing might cause problems as the axial loading might be higher that you require for the life of the truck. Do the sums to find out.

One approach is to ensure that the kart is sprung onto the rail and that there is sufficient elasticity in the parts to accommodate the variations. I have use long axil shafts on the under side bearings arranged that the axle had sufficient flexibility and spring to exert enough force to ensure smooth running under full load.

I tried using a driven axle supported in out rigger bearings. The axis drive being the friction between the rolling axle and the support bar. Worked well provided the axle did not slip and was very low backlash. Several pounds force was required to induce slipping which was adequate for the application where velvety smooth operation was the main consideration.

I would use linear ball races rather than manufacture a kart with normal ball races.

Regards - Pat

[hub]

I think it would require adjustment on all bearings.
And it would be a lot of work to machine the blocks plus lots of adjusting.

Why not get a ready made linear bearing with a block. (I ended up doing that). There are many who sell them. For $10 - $30 each depending on type, I don't see it worth making your own. Money-wise that is. Not to mention time spent.

Hub