I had been using carpet tape from Lowes as a two sided tape for hold downs. Then my roll ran out and I tried one from Home Depot and it was a horrible gooey mess. At about the same time I got a comment on one of my videos suggesting the blue tape/CA glue method, which I’ve tried and never liked. Jonathan Katz-Moses sums up my reasons for liking double sided tape better than blue tape pretty well here: Double Sided Tape VS The Blue Tape Trick - YouTube
I watched a few peoples videos and realized there is a huger difference in tape, and carpet tape is not meant to come off as easy and the main thing people hate about two sided tape is the goo, and if you have the right tape made for temporary hold down, it comes off very nicely. JKM in the above video recommended one brand of tape, but they were sold out so I just tried one I found on Amazon that was made for woodworking hold down. It works great so I thought I’d pass it on. I holds very well, but comes off perfectly clean unlike the tape I was using before, and its relatively cheap.
Its called XFasten and comes in various widths. I got the 1" wide and that holds very well. You still want to avoid putting the tape in the path of the cutter if possible to keep the tape from getting on the bit, but at least it pulls off clean without leaving little pieces that you have to pick off.
But if you follow Mark Lindsay, his main reason for sticking with the blue tape method is that you can burnish down both pieces (your spoil board and your workpiece) to make sure you get very good tape adhesion whereas with double sided tape you can only really burnish one side and the other side you have to press down on your workpiece pretty hard.
I personally am on the fence and can see the pros and cons to each.
Well, if you have to do that you applied it wrong, doesn’t matter which kind of tape. Remove it and apply new tape. Now if you want to apply pressure to firmly affix the tape, it’s not sticky on the other side until you take the backing off.
I have never had a piece of double sided tape come loose while machining. Usually, I have the opposite problem where in some cases I really have to pull to break it loose when I’m done. I think the burnishing is important for the blue tape because it doesn’t have much compliance, and the glue is not very sticky.
You can usually set it down wiithout pressure and still move it around, and then when you rap on it a few times its sticks very well (see the above referenced video, he demonstrates that pretty well).
Maybe a dumb question, but how do you make those shorthand reply boxes at the top of your replies with the originators name and a short piece of text that can be expanded into the whole orginal post?
The CA and blue tape works great for metal and plastic on metal worksurfaces. I use it all the time on difficult to clamp metal and plastics for the little Sieg X3 conversion.
When I first started cutting wood that is what I used and had an unacceptably high failure rate which is where I found XFasten.
But, truth be told, what I spend yearly on tape paid for 4 Lamb 122178-18 motors and a basic MDF table top. So the flow-through fixturing project is very much 80% along in design and will be the next thing I release. After that I am working on the 4 axis stuff and then the Plasma (true hole, water table level management).
If you already have masking tape and giant bottles of CA glue for other shop purposes there’s no need to get double sided tape just for CNC work.
I can see if you are doing hand-held template routing on a router (not CNC) table then the double sided tape might be more conventional for pre cut parts and templates, but for CNC work, blue tape and CA glue is the way to go.