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ajclay: IVTAAG for the X axis (Gantry) and IVTAAS for the sides......they discontinued the IVTAAS for some reason, and this really sucks if i need a replacement!
--John
John, I've been going through PBCLINIER's web site and I can't find the vee rail set up you have for the gantry. Do they still make that design? Can you put your hand on the part number? Thanks for the trouble...Originally Posted by johndjmix
Aj
ajclay: IVTAAG for the X axis (Gantry) and IVTAAS for the sides......they discontinued the IVTAAS for some reason, and this really sucks if i need a replacement!
--John
Coming along. I notched 2" angle and made the slat holders. Unfortunately it was late at night, and i was tired and rushed..... so, not thinking, i welded the angle on in that rush. The next day looking at it, it was so off...it was in almost a wave kinda levelness on both sides. I couldnt cut the welds since a 4 1/2" cut off wheel couldnt get that low AND i had allready bed-linered the thing. F**k!!!
Couldnt think of a solution. So I stopped working on it for a bit and went running. Somewhere around mile 4 of a nice 6 mile run it came to me. Grind a tiny strip off the outside of the angle and weld a 3/8 round on the outside of the slat holder and let the slats bottom out on it. As long as its as high as the highest slat they will all be touching it. Then align it using the gantry and z axis so its all the Exact same height in relation to a set point on the Z everywhere on the table. Did just that and its TOTALLY level now. Posting pics in case someone else makes this mistake.
I coated the entire water table with Rust-Olium Bed Liner. It seals any cracks in welds, and creates a really durable surface. Seems durable, but a bit flammable!...so i hope that part goes away as it drys out!
Candcnc has shipped and will be here next week. Im off on a trip to Colorado Tuesday, so it will have to wait till when I get back on the 18th.
--John
hey your table is looking great im building the same thing but im having trouble designing the water table and the location of the water table from the water table to the top of the table you think you can send me the dimensions ? it would be greatly appreciated thanks
Thanks for the complements guys!
duramaxer: Here is the measurement you need. Its 9.5" on mine. However, I would go 10.5" instead, mines a bit on the low side, i only have 4.5" clearance to the bottom of the TNG plate. (But i can raise it by putting blocks under where my rail tubes bolt to those plates.
--John
Crazy difference. I went 15" for the same measure and with my water table in place and the Hypertherm (if others are different- dunno) machine torch head will be able to bottom it onto the slats.
I maxxed out the vertical travel so that I could pull as much Z as possible for other functions.
I'm just posting some pics on my build now.
http://www.cnczone.com/forums/plasma...ml#post1096905
I'll need to install the torch head collar pretty low on the TNG slider but I'll have tons of vertical travel for 3D printing, routing and general recreation.
You've passed this stage of the build but the attached wire sag chart was something I looked high and low for... Keep a copy of it just in case you need it down the road.
I used a battery light bulb set up to slide under the wire and when it touched the light would come on showing contact.
Real accurate to say the least. Sorry no photos of my little light rig.
A couple more photos showing my slat set up and some other details. I tried to bolt everything together so I could be more in control of warping. Nothing is straight to start with that's for sure.
Anyway, just fuel for thought.
You're doing good!
Aj
I forgot the wire sag chart.....
The easiest things are the hardest sometimes!!
This photos shows the simple rig I made for the wire. The drill bit was for the spacing above rail....
Aj
Last edited by ajclay; 04-09-2012 at 09:45 PM.
I get what you did with the wire. I'm pretty perfect on alignment but at the gantrys far end of travel I can "rock" it slightly. Makes about 1/8 movement at the bottom of the tng plate. I spent about 5 hours to see what was off and for the life of me can't figure it out.
It's not that big of a deal, but since I basically have full adjustment in every direction. I should be able to get the rails perfect. I just can't seem to figure what the heck is off! Both are level (digital level to .1 deg). And they are parallell but being sure those v bearings are perfectly centered is a big tough. I'm close but want perfect. I'm sure I'll figure it out.
--John
John, If I follow what you're saying it sounds to me that you have a little twist in the two gantry rails. That digital level isn't as accurate as you think it is. Through in a couple feet of length and it can easily be off .100 or so.
To get it closer you'll have to diagonal two wires from the corners and look at the gap or where they cross in the middle..... OR....
You could use a "machinist" level and a straight edge from one rail to the other and compare the two readings you get from the ends..
At least the rails aren't welded to the vertical posts so you can shim.
I bolted almost everything to gether so things could be adjusted. Welding is fast but harder to achieve accurate results in the end.
you can make a couple of rods to compare things too... I used a rod to adjust my main slat beams the same distance from the top of my gantry rail.
Just fuel for thought...
Also can use a piece of tubing with a dial indicator stuck on the end for a comparator too..
Simple tools to go one step further on looking at things.
aJ
I bet that the bearings will run-in a bit over the first few full hours of cutting. Until then, every 1/1000th difference in distance between the rails will force an unloaded (light) ganrty into being a tricycle.
Also, are your ends of the ivtaag X 100% square? Until I removed a hanging bur from one bolted on end plate, I had one v-groove roller that I could see light through- it wasn't sitting down on the rail and a small teeter was evident.
My hex pan head screws from McMaster arrived yesterday so I'll be drilling next weekend. I'm off volunteering my time for a week so I miss all too precious home and shop time again.
My gantry rolls 100% now, but I figure I'll see something weird crop up in how the gantry rolls, perhaps, after the c-clamps disappear and the ivtaas rails are bolted down... Yeah, a gloomy thought but something's got to go wrong yet!
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