Does anyone use a Bump Stop to quickly set their material?

I am thinking of putting a Bump Stop on. I cut repeated patterns, Place, clamp, carve, & repeat. I believe a Bump Stop at the zero of X & Y would speed up my progress. Has anyone done this?

I just leave a couple of “clamps” screwed in all the time:

Yes, the X-carve is mounted directly to the top of my table, which is a very strong torsion box. It massively improved the stiffness of the machine, and made it really easy to square up with my big drywall square. I also intend to eventually change out the end plates and hold-down blocks to give myself more Z depth. Right now, it is very close to stock Z height available. I removed the wasteboard and extrusion thicknesses, and replaced it with 1.5" of particle board to provide screw-down surface and extra rigidity, with a thickness great enough that even a really spectacular crash with my longest bit can’t get to the top of the torsion box. lol

@PhilJohnson: I have my G28 position set at the lower left-hand corner of my clamping fixture. So I fire up the machine, home it, send G28 from the console, and zero out. Perfect corner alignment, every time. Then just jog to X1Y1 (or there-abouts, it doesn’t really matter at all) to clear the stops and make sure the puck sits neatly on the top of my work, and touch off the Z with the touch-probe setup you see sitting on the front left of the table there. I can go from cold shut-down to ready to cut in less than a minute with this setup. :slight_smile:

EDIT: Incidentally, the piece you see on the fixture there is one of these:

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@PhilJohnson - I had planned to do roughly 6 screws per MDF strip as well, but I was in a hurry to get cutting so I just did 3. They hold just fine, I’m not planning on going back to add any more, I don’t feel they’re needed.

I did cut the strips to be pretty tight between the T-Track, so there’s no side to side movement at all, and it takes a bit of pressure to slide them into place, so the screws are just there to hold it down really…

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Correct. G28 is a position in space that you set with the command G28.1. It is based OFF of the homed position, so you absolutely must home your machine before using it. Any time you issue the “G28” command, the machine will go directly to the position you set with G28.1. The position is saved in static memory, so it persists even after a power-down, permanently until you re-set it to another spot by sending another G28.1.

Fusion uses it as the beginning and end of each program, etc. It’s extremely useful, one of the best reasons to have homing switches, I think. :slight_smile:

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Agree with @DanBrown - When I bought my XC I bought the switches, but again, in my haste to start carving I just skipped them.

I’ve been doing a lot of repeat cuts (childrens’ name puzzles and signs) so I bolted down the square in the corner, which helped, but I was still doing the ole’ “manually jog the bit, stick paper under for the Z” and that’s just not consistent, or fast.

So, I wired up the switches, made sure I can home the machine, then set the G28.1 for the absolute X\Y position of my stop.

With @CharleyThomas’s zero probe, I can do Z in no time and I’ve decreased my setup time for the work 0 position to almost nothing…

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My original plan was to hog out an L shaped pocket in the lower left corner, then make an L shaped piece that sits down into it…

Then I saw that square sitting there and decided to just screw it down and call it a day :smile:

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I use a bumper board and a long clamp at the bottom. It makes setting up pieces super easy.

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Just a small clarification. The G28 command (and G30) are referenced to Machine Zero. So, you can use them effectively without homing your machine, but it is much nicer and easier to use them if you do home your machine.

I’m a big fan of homing, but those who don’t home can use G28 effectively as long as they know the rules.

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The answer is - it depends on your configuration and point of view.

During homing grbl moves all co-ordinates in the positive direction. When homed the machine co-ordinates for the work area are all negative.

There is a compile time option to have X and Y reported as positive numbers. Most of the .hex files (but not all) in the Inventables fork have been set for X and Y to have positive co-ordinates for the work area.

if you accidentally bump your spindle or move it manually you are screwed though

Doesn’t matter a whit. If you want it at 0,0, that is entirely fine. I can’t fit mine there due to the width of the fixtures and the clamps, but I could easily move my endstops to give myself more room if I wanted to. It’s entirely valid! You still want to set G28, though, especially if you’re using Fusion, so that it has the start-and-end point correctly assigned. :slight_smile:

Well, that might just fall under the category of not following the rules.

If you do bad things, bad things happen.

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I set my work home position using XY and Z
Coordinates I got after homing and then finding a good spot to use as the origin for my part. I touched off the Z, recorded that number ( as a negative #) and now I don’t even have to touch off my work pieces. When I start up the machine, I just jog to X0 Y0 Z1. and use my 1-2-3 block to make sure nothing’s gone screwy. Having the Acme Z is a big help, I’m sure. Using the G10 command loads this into memory, and I have it in every program I run.

Approximately how much travel do you have? Usable, I mean.
Really wishing I had bitten the bullet and got the 1000.

After I get ahead of this order, I will either upgrade or buy a second machine. Thanks.

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My X-Carve 1000 has 760mm travel in X and Y. Currently a few mm’s less (in X) as I’ve added dust guards.

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I just cut some strips out of a foam poster board I got from the dollar store. That stuff is amazingly handy!!

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Corflute (fluted polypropylene) is good stuff cheap but I manage to pick up a few pieces for nothing courtesy of a local election, It’s what candidates have their promises and photo printed on.

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Who knew something good could come of elections?