Rails

[hknisely]

I happing trouble keeping my Shopbot prt 48x96 on the rails it keeps jumping off. I re measure everything and it's good when it starts there is a suppen jump any help

[bob_reda]

one of your axis either the x or more probably the y is out of alignment.

Bob

[rb99]

Could also be one of the X motors is not working properly.

[Mayo]

Before getting into electrical problems, it's easy to do visual checks.

It's possible there is something stuck in the groove of one of the V rollers. This could lift it enough to make it come off the rail.

I had a similar issue one time when a part lifted as it was being cut. The router hit the lifted part and raised up the entire gantry enough that when it came down on to the rail again, it was out of square. Make sure the Y assembly is still 90 degrees to your X rails.

Also make sure the V rollers are all sitting centered on the rails. It's easy to get one slipped onto the inside or outside of a rail if you crash into a part.

[gene]

I would disconnect the pinion gear out from the rack and see if the gantry moves smoothly

[gerryv]

Don't assume that the stop blocks at the end of the rails are in the right place. First disconnect your steppers from the rack by dropping them, then loosen off one of the stops, roll the gantry back until it touches the fixed one and use a light bungie or someone else to hold the gantry snug to it without putting any twisting force on the gantry. Then slide the other stop block up to where it just makes snug contact with the other stepper pinion and tighten it there. This eliminates unintentional forced racking.

[hknisely]

I found my problem ever since I bought this prt ( used)
it kept jumping the track I took every ones advise one motor wasn't turning
found out it was the control box have to get new one so. I'll just upgrade to the 4g thanks for your help

[rb99]

I found my problem ever since I bought this prt ( used)
it kept jumping the track I took every ones advise one motor wasn't turning
found out it was the control box have to get new one so. I'll just upgrade to the 4g thanks for your help

I got it on post # 3!