For those who run with Dbl. Sided Sticky Tape as their preferred hold down method..... For smaller jobs, I have been using double sided sticky tape which has served me well. The only gripe I have with this hold down method is when I profile a cutout and it penetrates through the back of my workpiece and into the spoiler board (as it invariably does to a certain extent), it picks up a degree of tape and wraps around the milling bit. I have been cleaning it off with a blunt lead pencil and some WD40. is there a better process to release this gunge from the bit post profiling. Regards C
To be honest I stopped using this method for these reasons and now I usually screw hold down right into my waste board. It doesn't really hurt anything and it's a quick solution to get cutting. We are working on ideas for simple inexpensive hold downs that we can all use but in the meantime a couple of the guys here shared with me about how they use blue tape on both surfaces then a little super glow in between. They say it holds very well and is a quick and easy clean up after the cut is complete. I am looking forward to giving this a go. ========= < Material to cut ---------------- <Blue painter tape +++++++++ <Super glue (CA) ---------------- <Blue painters tape ========= <Spoiler (waste) board
I'm not convinced that method would work on my already furred up MDF spoilerboard. Painters tape now doesn't offer much by the way of adhesion these days it's designed to be tacky and easily removed so as not to pull paint off when peeled off. Therefore the only adhesion I see is the tape itself the superglue serves no purpose imo other than to stick the non adhesive side of the tapes together...I would be a little dubious about using this method if it was a long and intensive milling job...Imagine spending hours on a piece and it lifts on you ...I'd be well annoyed
You need to use the BLUE masking tape @Colin Mccourt. I haven't used the technique on my router, but I use the blue tape on my 3d printer - it's much stickier than the buff coloured stuff. You do need to clean as much dust off your spoiler board as possible though. Alex.
I use this technique on aluminum and plastics (to include HDPE which is slippery) and it works great .The two layers are also thick enough that I never cut into my spoilboard. I probably would not use it on a large 3D carving job.
Yep, lots of ways of doing this. For something small, like a PCB routing job, 2 sided tape is fine although I would mount it on a small sacrificial board because of the drilling. For regular wood routing jobs, I clamp it the old fashioned way but set Z zero on the CNC table surface. BUT, not exactly on the surface but 0.1 to 0.2mm above it. This leaves an "onion" skin on the bottom of the work piece after routing which is a breeze to clean off and no marks on the spoilboard. Occasionally, I would use a thin sacrificial piece as an intermediate board if I needed to use a twist drill right through the work but that's pretty rare. A vacuum board would be nice but that can wait for a future project!
I have my "P" clamps but get worried that the gantry router will crash into on especially on the finish and homing cycle
The graphic in UGS (if you use it) will tell you how the spindle exits the part on completion. Also, you could "manually" home the machine until its close to the end stops then press "Home" button. In other words, you can manually circumvent the clamps until the router is safely away from them, home machine and then put the axes wherever you like.
With the Duet you could home Z at the end of the job and then homeall. Your G - code for the job should leave your router over the workpiece and clear of any clamps @Colin Mccourt. You could also manually add g-code (with a text editor) to the end of your *. nc file to do this. Let me know if you want to explore that option and I'll let you know how to do it - IT IS NOT THE SAME AS STANDARD G-CODE FOR THE DUET. Alex. Edit - come to think of it - homeall home's Z first anyway.
I use the masking tape and superglue method. The tape I am using is made by Wurth. (we dont get fancy colors or types of tape here in Africa, so we just use what there is on the shelf). I have stuck foam to my MDF baseboard and surfaced the foam, an then stuck MDF , foam or even brass to the foam. I only allow a 1% of material thickness stickthrough so the bit barely touches the tape and I do not get any glue pickup. On bigger sheets I hardly ever fill the center of the sheet with tape, usually just doing the 2 short edges or even just one edge, then I put lumps of lead near the work area to hold it down during the cut.