Gap between X axis rails not parallel

Was thinking about ways to do the X axis rigidity mod, and noticed the gap between the two rails wasn’t consistent. On one side it was .125", and on the other .161". I think the wider end is correct, as the distance between the V-wheel rails on that side is 1.750. Although the narrower side is on the left, where I have been doing my cuts, as I haven’t cut anything to large yet.
But I wonder if I do cut something with a long X scale, if this will cause any problems, and what would be the best way to true it up.

as I was getting ready to do a stiffening upgrade of the x axis i noticed the same thing and when I moved the carriage across the x, i could see the v wheels riding up slightly on the maker slide as the two of them became spaced further apart. I have a set of machined brass set up bars that I use in my woodworking and with the 3/16" bar, I set each end at that spacing and discovered the center to be narrower by as much as 1/32".

I acquired a 3/16" piece of aluminum flat stock 1 3/4" x 39" and did the stiffening upgrade.
i also added angle brackets to the y rails in the center and anchored them to the wasteboard.

After finally gettign my new 48v 300w spindle installed and wired up, I lettered a sign in white oak using a 1/4" core box bit to a depth of 1/8" in 3 passes with virtually no chatter or tearout.

I am stoked that this mod paid off!

Here is the thread that gives real good info on this mod.

According to the STP file, the gap should be 0.163", and the mounting screws are on 0.951" centers

With a 3/16" filler my v wheels are spot on. and since the furniture connectors are not available to me locally I used #10 black pan head machine screws and hex nuts with loc-tite. The carriage clears just fine after cutting the bolt flush to the nut with a dremel cutoff wheel.

On second thought, the bolts may be #12, they 'just" slip through a 3/16" hole without binding up.

To drill the holes, I clampes the rails and spacer into a sandwich and used a good quality square to make sure the rail surface where the v wheel contacts are square to the front edge of the rail.

Using a drill press, i made sure My setup was square and drilled each hole in one pass, installing bolts as I completed each hole. I worked from both ends toward the middle with 5 bolts installed in total.

Thanks for the info. I had seen that thread which was why I was measuring that gap. Did you measure the thickness of your spacer, was it actually exactly 3/16"? As Tony pointed out, it seems to be designed to have a gap of about .160". I guess with V-wheels it could be slightly wider or narrower, as long as it was consistent. You didn’t have to slot the holes in the mounting plates? Seems like I might have to a little.

I did run a caliper over the aluminum plate before i installed it. It was within .002 overall. a couple of thousandths isnt going to make any noticeable difference.

The front holes in the mounting plates on mine were not slotted but the back holes were and no mods were needed to put the plate in.

I did drill a pair of holes in the plate that correspond with the top slot in the front makerslide. This is for the cross over stepper wire which I hot glued into the slot,

Ah, the plate is already slotted. Totally forgot, and couldn’t see it with the screw in place. Well that makes truing up the gap easy. And I just ordered a piece of 3/16" aluminum to do the mod.