[YouFoolishBoy]

Hi all,
Im at my wits end fiddling around with this and Id really appreciate some hints about how to solve it.
The basic issue is with a Solidworks assembly.

I have a frame made from ITEM aluminium profiles (its pretty similar to 8020 but metric).
I was gifted a load of it along with a set of linear guides by a very decent fellow. After sitting on it for a good while as I accumulated other bits I've made a start at last. The linear bits are 14mm ground rod that sits in a sort of cup extrusion that sits in the profiles slot with trucks that have 2 types; one with fixed wheels and one type with adjustable wheels.

To model my frame I used the CAD models from the ITEM catalogue, its an installable bit of software and as well as doing loading calcs etc it'll export to just about any CAD system.
Service

The trucks are exported as pre done assemblies, and Im really struggling to mate the wheels to the rod. I want to be able to work out clearances and dimensions from the model so I want to have proper contact between the parts rather than an approximation.

I've attached a couple of screengrabs, one I've MSPAINTed to highlight the areas of interest.
Im also going to try attaching a zipped up copy of the assembly with its parts.
The top level assembly is called BaseAndGantry.

I've seen this thread:
http://www.cnczone.com/forums/solidw...s-rolling.html
but its not a completely analogous situation.

I suspect part of the problem is that the inside face of the wheel may have been modelled as 2 truncated cones facing each other with a cylinder joining them, and solidworks doesnt want to mate the cones in the wheels with the cylinder of the rail.

I would have thought a tangent mate was required, but its grayed out (over constrained?). I've tried every mate option I can find and Im pulling my hair out.

Hopefully someone has faced this sort of thing before, but I've searched the net, viewed a ton of videos, and searched a load of forums with no luck.

Thanks for having a look, JHAttachment 244610Attachment 244612

[alan_3301]

remodel the roller wheel with a curve to match the rail, then a tangent mate should work.

Otherwise, fix the roller wheel model so that the planes are on the center of the model, the mate the planes so that they are coincident. Then set a distance mate to get the wheel the right distance from the rail.

[steelspinner]

Here is what worked when I tried it.

1. Use Width Mate and mate the center flat of the wheel with the shaft diameter.
2. Tangent mate the shaft diameter with one of the inside top (large) angled sides (use the top circle NOT the face).
3. You may have to mate the shaft perpendicular to one of the shafts running through the wheels.

I just tried it and it worked for me. Movement gets a little wonky. Should be just fine for dimensioning

[Mike 1948]

What I would do is: First, make all the parts in the double bearing assembly "Fixed" . Imported assemblies may come in with the parts in the right place, but if the are not "fixed" the parts can move until they are mated up. This way "all" the parts in the assembly move at the same time when used in other assemblies.
Second put a "axis in the "wheel" part along the plane the you want to match to the shaft. Use a sketch on that plane with a circle same size as shaft and make it tangent to the v sides of wheel. Use the plane and the center of circle to establish the axis.
Third, put a axis in the center of the shaft.
Then mate the two axis's "coincident"
You may need additional mates to get the base and gantry correct. There are other ways to do this(flexible vs rigid assemblies) is just one. BIG thing is to get your "imported" subassembly mates in order or make all the parts fixed.
Just my 2 cents.

Mike

[BuckNaked31]

Just make the sketch that has the revolve visible, then mate both lines that represent the mating surface tangent to the rail, then turn off the sketch visibility and mate your bearing plate parallel to the extrusion

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[bhurts]

Wow I think I'm to young for this thread. There's way to much mating going on.