Good Morning! I have a box making project I am working on and this is a fairly large project that I am running out of time on and would really appreciate any help the forum can offer. I am trying to use my Lead 1515 CNC router to carve out the area for my 90 degree hinges. My problem is that I can not figure out how to have any accuracy/repeatability in my attempts. I am running out of ideas for how to fix my problem. I started this project by flattening the bed of my CNC and drilling a dog hole area into the bed using the CNC machine itself so I assume that this is square and consitent relative to the machine and using the homing button will return the machine to the same starting point each time. I spent the time to calibrate the XYZ movements on the machine which to my surprise were all already correct. After this I checked the squareness of my machine and found that I am out 3/32" over the ~82" diagnol, an accuracy of .0011 which I am fairly happy with. My next idea is to learn how to test the backlash of the machine and see if that is causing my inconsistency. I have attached my dog hole grid file, my hinge cut file, and a photo of the results that I am getting in case it can help diagnose the issue.
Update, I have checked and tightened the backlash on the wheels. I had 5 wheels that needed to be thightened as they were basically free spinning. 2 on the y, 2 on the z and 1 on the x. Is it normal that some wheels that do not have the backlash adjustment on them to not be tight to the beam or is this a problem?
Hi Ethan, Can you explain the problem in more detail? What's happening with your cuts that aren't repeated? I can't seem to spot it from the picture. How are the cuts after tightening the wheels? Do you mean these Eccentric Spacer on the sets of wheels?
I am running into the issue of a lack of cinsitency in where the CNC is carving. Where I believe it should carve and where it does carve are in two different places. This would not be a problem if the postion of the inconsitency was the same for each box, however, where the CNC carves seems to change with each different run. It may be difficult to see even zoomed in, but if you look at the position of each carve, you will notice that do not fall in the middle of the piece of wood, some are not even in line with the other carves, and some are most are not the same length. I feel like I am trying to catch lightning in a bottle. Yet to test, was waiting to see if I should be looking else where for a solution, testing currently. These are the wheels I am referring to, the ones with just spacers, no eccentric nut.
Sometimes the brushes for the dust shoe are causing significant lift when the machine changes direction. Gary
Tested with the thightened wheels and the same issue persists. The top carve should have fell in the middle of that portion of the box wall and I do not know what to do at this point.
Id be doing test cuts on scrap until you figure it out. First you need to work out if its the machine slip, or something you or the app is doing, or the workpiece itself. I would run a couple cuts from the exact same start position on some scrap and just bump X or Y 10mm and re-run. Same results each time? Get out the calipers and make sure the distance on 1 cut is exactly the same as what's defined in your .crv and repeated on the next. The boxes themselves would also have slightly different specs, 1mm here and there over 9 boxes would be a significate issue. Clamping compression could potentially also be an issue. Wood does swell and compress with humidity, individually maybe not an issue but over 800+mm and 3 boxes it could. If you're cutting all 9 boxes at a time, scale it down, 1 box ok? increase to 3 in X Axis if that's good, add back 2 in the other axis. That way you could pinpoint which axis may be having a trouble if machine related. Is the inaccuracy being repeated each time in the same location? As a work around, until you figure it out and to keep production running, you could just run a single mortise cutout at a time, manually adjusting the location. Dustboots have a way of bunching up the bristles on direction changes, forcing either a lift or a axis slip if they are sufficiently firm or crammed enough. Try a cut without?
Is the cut file you are doing for the hinges based on everything being evenly spaced? If so, I looked at your crv file and I only see one box drawn. That and the dogs are not arrayed in an equally spaced grid across. Probably due to the T-track. Where are you starting the cut from (XYZ 0 point)? The reason I ask is that if you end up back at the XY 0 point after cutting then you are not loosing steps. I would then suspect it is a calibration issue, a CAM issue, or a mistake in the zeroing of the X nd Y axis. In other words, you tell the machine you have a 3.175 mm endmill when using the touch plate, but in reality it is slightly smaller, or slightly larger. But this would lead to an error on the first one and should be consistently off I would think. As mentioned above, if you are in a hurry to get them done and the first one is cutting right, just keep rerunning the file on each box in that spot. Then try to figure out the problem when you are not pressed for time.
Removing the dust shoe helped with a different problem i was running into, glad to see that solved, Looking forward to tomorrow when I get back to the hinge problem!
The Dog hole layout is saved as a template I can align to in Vcarve, it is the same file that I used to cut the dog holes. I am also using home as the X/Y zero and setting Z0 with the touch plate.
