Machine Alignment
Reply with QuoteRance,
I have taken a few of the posts I saw and assembled them in one document. I can't tell you which posts but at least one of them was JGRO's.
None of this is my work but it is an alignment proceedure
Here's the Document text
I usually made my holes larger to allow for inaccuracies/adjustment. If you made your holes to size and your holes are off by .010, it probably won't work. Here is how I assembled the linear bearings:
For assembly #8, clamp a piece of wood to the side of the angle parallel to the bearing that you want to assemble. Stick a bolt through the hole and put a spacer on the other side. Put the bearing on next. Screw on another nut to hold the bearing on. Don’t tighten the bolt yet. Put a Vise Grip C-clamp on as shown in the image below to preload the bearing and tighten up the nut making sure that the bearing does not pull away from the piece of wood. Tighten up the bolt.
{The Diagram goes here}
Take a 4 blocks of wood that are cut to the same height and place these under the rails. Use a large carpenter square and set one of the rails square to the base. Next cut 2 pieces of wood that can be used as spacers to place between the two rails to keep them parallel. Check with your square to make sure that the second rail is square to the base when you are done. That should get your rails close. You may need to adjust one of them later to get them to mate up with the bearings on the gantry. To set the gantry, this is what I did. There are 4 drilled and tapped holes in the bottom piece of the gantry shown on the drawings. These are for jack screws. Set the bearings up as I showed in post #66 of this thread. That is your starting point. Next set the gantry into position as close as you can, adjust one of the rails if needed and screw some bolts into the jack screw holes. Screw the jack screws down until they just touch the base. Loosen all of the bearing bolts. Measure from side to side to make sure the gantry is set into the center of the machine. Next place a level or something that you know to be straight and stiff across the pipes behind the gantry and measure from the level to the bottom of the gantry. Adjust the jack screws until both sides read the same. Do the same thing for the front of the gantry. Once all the measurements are the same, take 2 wood screws and screw the gantry down tight to the base. Now you can tighten the bearing bolts. I used a Vise Grip C-clamp to clamp the bearings tight to the pipe and preload the bearings. I hope this all makes sense.
Alternative Method.
I did not use the bolts you have circled to adjust the tracking of the gantry. And this was the trickiest part of the assy. I used the two bolts holding the Aluminum angle to the MDF gantry frame. What you are attempting to do is to get the two long gas pipes to be absolutley parallel and level and seperated exactly at both ends. That is the easy part. What is difficult is to get the gantry set up so the center axis of the two linear bearings are co-linear with the axis of the gas pipe tracks.
The problem is it is near impossible to "see" and thus hard to set the axis of the linear bearings. I used the gas pipe to do this. I took the gas pipe out of the base assy, then set the gantry (all by itself off of the tracks) and set it on the work bendh. I took the two long gas pipes and used several strong bungie cords to pull then into the side bearing assys so the pipe extended out in both directions. Imagine the drawing you have attached above, except only the gas pipes are installed into the linear bearings with no support at their ends.
I then used a level to get both pipes (only being supported by the gantry's linear bearins mind you) in the same plane. Then I used a tape measure to get the two end of the gas pipe equa-distant from each other. Then I tightened every thing down. Once the gantry linear bearings were square, I put the whole thing together into the base and using the level and a tape again made sure the pipes were level and square in the base.
Sorry to the authors that I could not specify the actual Posts but I hope this helps.
