I seem to be getting a lot of vibration. The machine has been leveled and all of the feet are solid on the ground with no gaps.
Is this normal or is there something wrong?
Thanks in advance!
Normal. There is a fair amount of mass being slung around. It can get a LOT worse if you increase the speed. It is not unusual for me to reduce feed speed to reduce vibration.
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I can’t see any images but I do hear sound on your video. Maybe a problem on my phone. I’m guessing it’s your table that’s vibrating?
Many Altmill owners have stiffened the legs using a variety of methods: bracing, cabinets, shelves, etc. I made leg stiffeners on three sides (left, right, rear). I was going to do the front, but with the 3 stiffeners on the legs and the Baltic birch table, I figured it would be stiff enough. I may make one for the front eventually.
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I built a 2x4 and 1/2” ply shelf in the legs at the halfway point; stacked a pile of stone to dampen the racking. It helped, but there’s still a gantry changing direction a half a dozen times in a second. Don’t feel like you have to be fast.
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i own a Longmill 30x48 . I made my cnc table from an old kitchen table with long legs. i never bothered to firm them up and i think as a result it has movement in it as the spindle changes direction , especially on rapid direction changes. i am going to leave it like that because it acts as a shock absorber and there is not as much G force on my x and y rails. i have machined some very small lettering and it seems to be very precise and accurate. just a thought .
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Be sure the guide blocks on the Y rails are tight.
When I put my Altmill together I mistakenly used the wrong bolts (too long) and had a lot of vibration. Now I check them regularly to make sure they are not loose.
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@JDWW I’ve checked all the frame bolts but I will re-check the guide blocks as well! Thanks
I noticed that when i put my 1 1/4” surfacing bit and I don’t insert it into the collet deep enough it has some vibration. I always make sure now that I clean my collet from debris or dust and insert the bits as deep as I can with regard to how deep I’m machining into my workpiece.
This is incorrect procedure. You need to leave room for the sliding action of the collet.
In general, you should insert the bit so that it just clears the upper (inside) portion of the collet.
If you go a bit beyond that, no harm done … but if you slide the bit in far enough to hit the end of the collet cavity, you will not be able to properly tighten the bit.
From the limited testing I have done, it seems that if you are near the area where the flutes start (but still on the solid shaft) you are golden. Of course that doesn’t apply to a surfacing bit as there are no flutes. In that case, and to be sure, loosen the collet nut all the way, remove the collet, insert the shaft of the surfacing (or whatever) bit into the collet until it just peeks out of the back of the collet and make a mental note how far the bit is inserted. Remove the bit, reinstall the collet, insert the bit to the same position and tighten the collet nut.
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What @Jens said. Plus, you want to stay away of any radius where the shank meets the head of the bit. If the shank doesn’t bottom out before you reach the head, pull the bit out a bit to stay clear of said radius. Otherwise you won’t tighten it properly in this situation either.
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Is the table vibrating or just the display?