Inventables Community Forum

Help to hold down 18 internal cut through shapes

Hi Guys : new to XCarve and need some help. Carving all the way through ( 6mm MDF) a split monogram letter with added flourishes. Using easel cut outside format im going to be left with qty 18 small internal shapes that will be scrap. The size of the monogram is 22x22 inch. How do you hold down all these internal shapes to prevent them from flying off everywhere once through cut is complete. Please dont suggest that I use tabs for each shape. Does that mean I have to tape the entire 22 x22 inch back with tape and super glue.? Anyone had any experience with holding down a large number of shapes that are formed during through cutting. ? Thanks

Double sided carpet tape or double sided duct tape?

https://www.lowes.com/pd/Shurtape-1-88-in-x-12-Yard-S-Blue-Heavy-Duty-Duct-Tape/3014450

The other thing I do is not rout all the way through but leave a few thousandths of material to cut away with a hobby knife.

1 Like

how can you get that accurate? Ours is always at least .0625 into wasteboard or .0625 above… and thats a lot of sanding, or at least seems to take forever.

Hi Thanks for the reply. To reiterate im only starting out but have heard that using a 1/16" bit inodrer to get into the tight spots, the glue on the backing tape gums up within the cutter flute.havent tried it but are prepared to give it a go. The other issue is that I find I have to put in a material thickness greater than it actually is in oder to get breakthrough into the waste board.I dont believe I could achieve a depth accuracy you stated and with a 22 inch x 22 inch board with a multitude of cutter paths cutting it at the end with knife would be a pain and sanding it into tight fine corners almost impossible.?

Use a lot of tabs then use a razor knife to cut them out, after running your monogram, rerun the project at full depth that will clean up the edges a bit. I use a 1/8" bit on mine. Yes you get rounded corners but remember step back and look at it from the distance you would look at it when it is hung. at 22" inches the fine corners are not noticeable. I set my material thickness .03 thicker than the actual board. I gave up n MDF and solely use 1/4" PVC board a lot easier to deal with on monograms. Paint it first, cut it then you get a nice clean look with white edges.

1 Like

I have a cnc4newbies Z axis.

Cutting through the tape does get gunk on it. I cut a script logo out for a friend with a 1/16" bit recently. I paused the cut and router when it needed cleaning. I carefully used a piece of wood as a scraper and pushed it gently downward along the edges… I used a different cnc router though, not an x carve.

The only other thing I can think of, and I’ve done this too, is not cutting it through the material and running it through an abrasive planer ( performax like sander) until the area between the pieces are nearly transparent, then break them off.

1 Like

Thanks Steve : Brilliant idea on rerunning the program to clean up edges will try it. Have seen some of your work especially the white and pink dog training sign.Absolutely sensational.If you can achieve that level of detail and POP in your signs im inspired. Will try and get my hands on PVC as my interest is to do signs for outdoors and im researching what timbers or acrylics are best suited . Thanks again for the great advise appreciate it.

Use the Blue painters tape and CA Glue Method, also use a piece of 1/4" MDF below your project and on top of your wasteboard so you can cut all the way through and not damage your original wasteboard.

1 Like

I totally agree with Robert10. Best and the only way I do it.

Hi Robert : Thanks for the response. So in order to capture and hold all the internal shapes I would have to put painters tape across the entire 22" x 22" piece which I can do.That’s OK. But wouldn’t you have to apply CA glue to entire surface area of the painters tape to ensure the glue is present under all the internal scrap pieces to prevent them from coming away during cutting… Do I use a brush and flood it on ?.Dont you use a lot of CA glue that way . Why I ask this question is that currently ill have approx 18 internal shapes that I need to hold down.The big picture, is that I also want to ,in the future, cut out a large 30" circular dia with a “circle of life tree” in the centre. Thats going to create a massive number of internal scrap pieces between the tree branches/leaves and roots. Literally 100’s of pieces I guess. How to best deal with it ?

In this case I would likely still use the painters tape method but I would also use another cutting path to completely hog out the small waste pieces rather then profile cutting them and having a bunch of floating waste. The CA glue generally needs to be in thin stripes and will spread out, full coverage would not be recommended as that could be a nightmare trying to get the parts off.

If you will have a ton of small waste like I say above, set a tool path to route out the waste rather then hold the waste with tabs and tape. Experiment with a scrap first.

1 Like

I think this is where my current limitation becomes a problem. Im using Inkscape to drag in a tree image. Creating a bitmap trace as a vector and saving it as an SVG file. Dragging the Inkscape SVG file into easel .All good. If I choose a cutter path cutting outside all the scrap pieces are recognised and can be removed during cutting. If I change to pocket.The tree then becomes the pocket hence the waste pieces cannot be pocketed or routed out separately as you suggested.Should I be looking at other software that will do as you suggested.?

Whenever I need an SVG image I go to Etsy.com and search for that image which inevitably somebody has already created. I’ve not ever paid more than about two dollars for a perfect crisp SVG image.

Give that a try, you may find exactly what you want already exists in the format you need

1 Like

I second the Etsy recommendation. Really solid, well done designs there for cheap.

I made a couple of signs once carving through half inch PVC and did NOT do tabs or tape. The pieces starting popping up and interfering so I stood there for the duration of the job using a pencil to hold down the pieces while they were being cut out. Next one I put in tabs … I find that if you spend a few minutes dragging them to a good spot, they’re not to hard to cut out.

I agree! We use this method a ton.

The pocket change as you are describing it can be done easily in Easel most of the times, if you want to PM me or share your file I will look at it and see if we can make it work for you and show you how to do it, Steve

Darren 1
When ever i cut out shapes of any size or what ever I always use a 1/16 downcut end mill and cut through with that the chips are pushed back into the groove or cut and hold the item in place.

2 Likes

I created a vacuum board to hold stuff down, essentially cut a hold for a vac hose in the bottom of your waste board and insert a shop vac. Then, create a second waste board with a grid cut out of the bottom and holes in the top and mount it above your vac hose. Mount your parts to cut on this vac board, turn on the vac and start cutting.

Double sided tape to hold things down, use a v-carve toolpath (90 degree v bit) for the first .125 to get the sharp corners on the surface, then cut it all out inside the line with a .125 bit. You won’t notice the rounded corners