CNC Hold Down Methods: Workholding and How to Clamp Material to Your Spoilboard

Hey CNC Woodworkers! This video covers 10+ different ways to do work holding on a CNC table. I have different techniques that I prefer for different types of CNC router work, which have evolved a bit over the years. I specifically discuss ways that work best for a t-track spoilboard table, but I used some of the same hold downs with my 1/4-20 pronged t-nut table. Some techniques are better for toolpaths that are only cutting in the middle of a workpiece, others are better for flattening the entire worktop, and some others are best when you are machining away the entire sides of a piece (like CNC'ing a bowl). I briefly discuss vacuum tables and chucks, but I personally do not have one of these (yet!).

You are free to copy my 3D printed designs, and would be a great exercise in CAD. If you want to just get the files I made, I have them available here:

*CAD Design / STL Files*

*Materials / References*

*NOTES:*

*Double Sided Tape:* I prefer the Intertape brand listed above for the reasons I listed in the video, but I have used the other tapes, and they do work, and are cheaper.

*Composite Nailer:* I have NOT used the composite nailer. Usually I only put links to things I actually use on a regular basis, but I want to give a full disclaimer that I have not tried them myself. I would definitely give it a try if I didn't have a vacuum table and was doing sheet goods on a regular basis.

*Blue Tape/CA Glue:* I don't like to use the Blue Tape and CA Glue method anymore, but it is worth trying if you have it around and don't have double sided tape, and you can find the materials locally (Home Depot, etc). I found that a higher quality blue tape works better than cheaper blue tape. Thin CA glue works best, and accelerator
"sometimes" causes issues, so I stopped using it. The glue also doesn't work as well as it ages, even in un-opened bottles.

thanks!
Corbin Dunn

*Chapters:*
0:00 Intro & Overview
0:29 1 - Low Profile Toe Clamps
3:12 2 - Slotted Wood Top Clamps
5:29 3 - Scrap Wood Top Clamps
6:36 4 - Metal Top Clamps
7:13 5 - Side Cam Clamps
10:21 6 - Wedge Clamps
13:47 7 - Double Sided Tape
16:42 8 - Blue Tape & CA Glue
17:41 9 - Screws & Nails
18:53 10 - Vacuum Table / Chuck
19:27 Conclusion

* The usual disclaimer - some links are Amazon affiliate links, where I earn a small commission from your purchase at no cost to you. If you only knew how much crazy amounts of time I spend making videos!

[MarkLindsayCNC]

Excellent video, Corbin! I guess it goes without saying that sometimes there is no single "best" method. They all have their place. We just need to learn the different application that works best for the job we're getting ready to run.

[mikegoins]

Thanks. I learned something new. I liked the good and bad for each hold down.

[dominaspina]

Wonderfully informative video. Thank you for going through the pros and cons of each method. As a CNC beginner I get to benefit from all your trial and error.

[samrix]

I really like your videos and content!

[Curtis-Randall]

This video was super informative! Thank you for going every method, it helped me decide which kind of bed to make for my cnc.

[maximazur]

Hi Corbin! Great video! I made a 100mm grid of tnuts that go through the spoilboard and the backing MDF, so I can tight any bolt lengths. Another great addition to my CNC router was to design an auxiliar spoilboard as a vacuum table: with a square grid, a hole in the center, a 3d printed adapter for my shop vac and a long gasket to close a perimeter. You should try that! Works like a charm

[robertyack]

Great job. I'm about to pull the trigger on DIY ATC based on your video series. I have a 5x10 Avid CNC. You may be hearing from me, sir. Love your style of teaching

[DavidBeede]

Love your videos. They're well thought out and executed, like your shop and woodworking! I was hoping you'd have a DXF file of your spoil board. Very generous of you to share your drawings and cut files, except I don't use Fusion, I'm a Vcarve and Rhino guy. I guess beggars can't be choosers and all that. I'll just have to draw it myself. Keep up the great work.

[RAPTORNailsStaples]

Great video! We (Raptor Nails) are a little partial to the composite nails method! 🙂

[bloho_design]

Another great video! I’m pretty scared about running into hardware so I’ve done nylon 1/4-20 hardware, and am lazy so will tap the hardwood for threads instead of embedding a nut (since I don’t want to use metal t-nuts..)

[KABATAPE]

I'm wet behind the ears, always listening for good advice, this was a great review and insight to the forces at play.
I will purchase the 3D toe clips.
The plywood stock I work with is always less than 0.75 and more than 0.65 Will the 0.5 clip suffice? or should I request a 0.625 clip designed?

[iderryan]

Depending on what I'm cutting, I can add a tool path for screw divots as the first cut. By doing this, I know that my screws aren't in the way of other tool paths. If I know the exact locations of my dog holes and t-track (because I have the file I used to create them in the beginning) then I can use those locations for nylon hardware. Mostly, I use maple, ash, or oak for simple bar hold downs. 0.75" thick, 1.25 wide, and 3-5 inches long. A slot in the center for the t-bolt, and then cut a rabbet on each end 3/8" square. This is super easy with scrap hardwood on the cnc, then just cut them to width on the table saw.

[braunproductions]

Love your channel. Since you are the youtube channel that most resembles what i would do with a router table I would like to know what you would order if you were to start over today? Basically tell me what to order from who and hopefully I can afford it and place my order right away. Thank you in advance

[dangoras]

That's one way to use a body hammer 😂.. Good information brother I think I will stick to double sided tape.. Keep it up brother

[AndyBlackman]

The AirWeights Workholding System seems to be promoting itself on the socials lately. Kinda pricey. Looks interesting though. I think its is directed towards more production level workloads.

[ClintonCaraway-CNC]

PwnCNC sells toe clamps with square washers for reenforcement.

[billysmether]

A vacuum will not hold down small parts. There is not enough surface area to create downward pressure. It can hold down a small part if it is connected to a larger base piece. I have tried them all. I screw everything to the machine bed (MDF). Super fast, super secure, and nothing for bit to jog into. Thanks for video!

[ChinJazz]

Hi Corbin,

First, a huge thanks for sharing all your methods for CNC hold downs!

I'm a Guitar Luthier, and moved into the world of CNC to help with certain operations (1st "Employee")..

This may add ideas to your tooling designing :) -> Pay it forward right?

Now, I need to find someone to print me come of your Side Cam Claps!!!

Any way, again, thanks for sharing!
Cheers, Adam

[maddogtungate]

I don't understand how people seem to always run in to their hold downs when you can program the cnc to go above them.

[cliffart]

The 1/4-20 you used is not a nut but a bolt. I have made mine out of wood.