I’m getting ready to install both X-Carve Upgrade kits, but just noticed if I install the Z-Axis upgrade kit according to instructions I will lose the ability to “align” the gantry to the Y-Axis rail mounting brackets at startup.
I’m one of those X-Carve owners who has to pull the gantry against a pair of spacer blocks at initial startup to ensure correct alignment of the X-axis. Otherwise, it starts up in a “skewed” orientation with the right side about 2 mm back of the left side.
I suppose I could always flip the brackets so they are installed (oriented) more like the original mounting brackets, but that kind of negates one of their design intents.
I’m just wondering if I’m missing something before I start the tear-down and upgrade process or if other users who installed the upgrade kit have a solution to a similar problem.
I just checked with @LukeWilson1, he mentioned trying to start blocking on the outside of the makerslide vs the inside.
I would address the root cause and elevate the need to use the blocks in the first place.
You could loosen the wasteboard and lower frame components and bring the frame into square better and this would also help to bring the gantry into square making the spacer placement a moot point.
There are other more involved methods to get the gantry to retain the correct alignment naturally, without the use of the blocks 
Thanks for that idea!!! I’ll look into it.
I agree, if only I can find the root cause.
As far as being square, I just checked & recorded results before tear-down, and I’m within 0.25 mm on the diagonal measurement of 1045mm. And that’s using four 1" x 1" posts at each inside corner. Plus I have made 2 spacers to fit inside the Y-rails front & back…both are equal in length and I’m satisfied with their fit, so the rails are parallel. I’m not sure I can get any better than that!!!
When I first reported this problem to Inventables during machine assembly in 20018, their support staff suggested the end cuts on the gantry rail may not be a perfect 90 degrees. Given that other users have reported a similar problem and use a similar solution, I decided to live with it.
Thanks for your response, and if you can suggest any other ways of confirming the X and Y axis are parallel and square, I’m all ears!!!
There is something causing the gantry being in a skewed position. You should not have to pull it forward to the blocks. If you are within a .25mm of being square then perhaps as you pull the gantry forward it is being pulled into the skewed position by that action
I did a little video to talk through the scenario and some possible solutions to a non-square gantry movement. Here it is:
Let me know if there are any parts that are unclear, but in a nut shell, it doesn’t matter so much that the frame is square as long as the spindle movement (X to Y) is square, so to get them square you may need to take the frame slightly out of square, and that’s okay.
I’m sure it’s not Ideal, but okay if it gets the cuts perfect, and eliminate the extra step of blocking every power up, right?
Thank-you so much for putting that video explanation together!!! I do know that the Y-Axis tracks perfectly, but if I don’t use my “start-up blocks” the X-Axis cuts will not be 90 degrees to the Y-Axis cuts. Since I have to essentially disassemble everything to install the 9mm belt & stepper motor upgrade, I’m going to take another run at aligning things, keeping in mind your suggestions as I begin the re-assembly process. I’ll pay particular attention when I re-attach the gantry to the RH stepper motor/v-wheel bracket
Square your machine without using a tape measure
the main input that I have is that not always does a square lower frame make a square gantry movement.
I would much rather have square gantry movement than a squared frame, so you can follow Phill’s squaring guide, but it is not necessarily going to produce square movement… it usually will, or close enough that most users won’t notice, but not always…
If a square frame fails to produce square gantry movement when started from its from the resting position, take note of how far off it is an adjust the squareness of the frame (by skewing it as needed) in order to get square movement without forcing the gantry into any stop blocks. 
I took your “root cause” suggestion to heart, and the more I thought about it, the more I remembered dealing with this issue when I first assembled my machine. That’s when my Forum research led me to the “alignment block” solution. The attached picture picture clearly shows the X-Axis makerslide LH end has not been cut square. Similar problem at the RH end…not quite as bad.
I just sent a support request to Inventables regarding a replacement X-Axis makerslide.
Thanks again for all your help!!!
