New Pocket Screw Joinery

[Chris Larson]

Hi All,

It looks like Build 12 has some cool additions. I am most interested in the new pocket screw joinery. Are there any instructions or tutorials for this anywhere? Will we be able to develop our own customized pocket screw hardware patterns? How will we get the pockets to appear on the opposite face of the default setting? How do people like this feature? Is it effective? Any information on this would be greatly appreciated.

Thanks,

[Josh Rayburn]

Let me know how you like it once you've tried it out Chris
jnr

[Scott G Vaal]

Chris,

Thanks for your interest in this feature. The pocket screw hardware pattern is fixed and cannot be changed. To switch face sides for the pocket screw, simply go to construction parameters for the part in question and select the side you want them on (it can be different for each part and each edge per part). You can also decide per edge if you want the mating part spot holes (I’ll explain a bit later).

The challenge for this joinery was efficiently fabricating special angled pocket-screw holes using a standard, 3-axis CNC machine, without the need for specialized drilling heads or tooling, and without the need to remove/handle the part for additional discrete operations.

The following drawing gives an idea of what the result at the Thermwood machine will look like when ran through Control Nesting (In eCabinet Systems, it will look boxier).

We use a 3/8” flat router bit to create the main angled pocket hole. This tool ramps down at an angle and then drops to create needed clearance for the screw head and then ramps out to create a perpendicular wall to the main ramp in move. As an option before this main pocket machining is performed, we can take a 1/8” or up to 5mm flat router bit and plunge a hole to create a ledge in the screw head surface. This ledge is used to locate the tip of the screw and guide it at the correct angle. After the ledge hole cut, there is yet another option to use the same tool to create a clean-up along the two outer edges of the screw head surface to create a flatter surface for the screw head. This clean up pass may not always be necessary, however it proved to be helpful in preventing cracking/splitting of melamine or pre-finished material surfaces. If this is not a concern, it can be left out. The screw tip ledge has proven to be very useful for guiding the screw at the correct angle. The result will looks similar to the drawing above. This method does not have a pilot hole through the part, so a self-drilling screw is recommended and seems to perform well. The following cut away view shows more detail on how this works.

The head of the screw lays on the main curved ramped in surface and the tip sits in the ledge thus aligning the screw to the proper angle. Now, you attach your driver bit and let the self-drilling action of the screw lead it through.

Another component of this joinery is an optional shallow spot hole that is created on the mating part. This option is defined in eCabinet Systems and can be turned on/off per part edge. See picture below (picture shows lock dada with pocket screw).

This spot hole serves two main purposes. First, it clears any hard melamine, laminate, or pre-finished surface that tends to prevents the screw tip from easily getting started into the mating part. Second, it helps minimize the chance of the material surface chipping and bulging up hindering a tight connection and also helps provide a relief for any bulge out from the screw exiting/entering the connecting parts.

Hope this helps explain the joinery a little better and thanks again for your interest.

(Machine user note: Only supported in Control Nesting version 5.78 or newer. Please refer to Control Nesting manual for tooling setup requirements.)

[Chris Larson]

Thank you Scott,

I didn't notice the selection box for top/bottom of part before you mentioned it. Now I see it and it is obvious. This is a lot of good info. Just what I was looking for. We will be testing this joinery soon and I will post about our experience once we have some results.

Regards,

[Forrest Chapman]

Chris and Josh, we have been cutting some jobs with this feature and everyone including us are raving about it. When we first tried it was painfully slow to machine because of how the code was written but they have since made changes and it works like a charm. It is very fast to assemble and cheaper than camlocks but is still very strong with or without glue. I do not use the side cleanup holes only the center one.

Forrest

[Michael RA Greschuk]

Hi
Is this joinery going to be available for the shopbot link?

[Ray Jorgensen]

I just got done cutting my first pocket hole.

Fantastic!!!!!!!!!!!

I can't imagine the challenges the programmers had in figuring this one out, but Kudos's to them!

I haven't even explored the other additions to e-cabs, but this tickles my fancy.

Thank you very much

[Kerry Fullington]

I am a little late replying to this thread but wanted to throw in my 2 cents.
During Beta Testing I posted that the new pocket screw holes took to long to machine and we were going to use our old system of just a slot applied as a KD/RTA fitting. Since that time I performed a couple of tests and found that the Thermwood holes take about 12 seconds per cycle (with tool changes and machine travel) and our slots were only about 6 seconds. With an average of 500 holes per job this is quite a bit of difference.
Recently I tried the Thermwood holes again on a melamine job and the assembly guys really like the shoulder for positioning screws and the fact that the router "pecks" through the melamine on the mating piece which made the screws grab easier. I have now decided the benefits for the assembly guys makes up for the machine time and we are using the Thermwood holes.

[Forrest Chapman]

You know Kerry I took your joint and added that little center drill to make the shoulder and the peck drill on the adjacent part. The only added time to your cut is as a dado it goes around twice where as with the pocket slot it only ramps to depth as 1 pass. I would think that is a little faster.

Forrest

[Jim Carter]

This is a good thing!! If I can get it to work.
I have noticed that the lock dado tenon gap setting is not in the same line as the inset and max dist. Settings for the right and left edge of the kd/rta lock dado, pocket screw placements settings. To get a tenon gap on the left edge of the top I must set the tenon gap on the right edge.

I have Question about tooling. What tools have you been using to complete the three steps in the pocket hole route and how are you setting them up in control nesting?

[Scott G Vaal]

This is a good thing!! If I can get it to work.
I have noticed that the lock dado tenon gap setting is not in the same line as the inset and max dist. Settings for the right and left edge of the kd/rta lock dado, pocket screw placements settings. To get a tenon gap on the left edge of the top I must set the tenon gap on the right edge.

I have Question about tooling. What tools have you been using to complete the three steps in the pocket hole route and how are you setting them up in control nesting?

Jim,

Seems like the lock dado tenon gap has been reversed for top/bottom and right/left since the beginning of the lock dado joinery in V6 Bld 10. Apparently most people are using the same gap all around, which I would guess is the most common. Nevertheless, it is an issue and we will get it resolved.

As for the tooling, here at Thermwood we have been using the same 3/8" cutter that is used for the dado operations (a real short up-cut compression spiral) to machine the main pocket. I prefer a 5mm drill/router bit (up-spiral) to create the screw shelf/ledge, but an 1/8" drill/router bit can also work for this. The 2 clean up moves with the same bit are optional. I like using the 5mm because it is the same tool that typically performs shelf/hinge holes and is also used for the spot holes for the pocket screw joinery. This way you can do all of them at once without an extra tool change. Please refer to the Control Nesting manual for how to set the tool names up for this. Just make sure you create/set the tool names on a separate operation or it will not use the tool for anything else. Hope this helps.

[Jim Carter]

it helps thank you Scott

[Terry Hall]

Hell, Michael we can't even get the tabs fixed, which has been screwed up for the last year and a half, and you're asking if this is going to be available for the shopbot link, get real. Apparently it's okay to sell the shopbot link and make a few bucks, but to support, nope. And that makes no sense since Thermwood seems to react to problems posed by non-machinists who've paid nothing, as opposed to those who have ponied up and paid something.

[Steve Detina]

Hello Thermwood team,

Great work on the new joinery, looks good. I have been playing around with it and would like to know if there is a way to extend the mortise and tennon tabs. For example. Below is a image of the back of a cabinet. Is there a way that another dado can be machined above the top pocket screw and below the last or bottom pocket screw. I ask this only because if you place the screws to close to the ends it has a tendancy to split the plywood. If you keep it further up, there is no joinery to keep it secure.

Kepp up the great work.

Steve

[Scott G Vaal]

Hello Thermwood team,

Great work on the new joinery, looks good. I have been playing around with it and would like to know if there is a way to extend the mortise and tennon tabs. For example. Below is a image of the back of a cabinet. Is there a way that another dado can be machined above the top pocket screw and below the last or bottom pocket screw. I ask this only because if you place the screws to close to the ends it has a tendancy to split the plywood. If you keep it further up, there is no joinery to keep it secure.

Kepp up the great work.

Steve

Steve,

No, it does not allow for that. I did not really have much of an issues with it splitting the plywood when testing (We used self drilling screws). I of course made sure my drill clutch was set properly. I did tests in melamine, plywood, and MDF. In most of the tests I had the insets set to 1 1/4" from the ends and it worked very well for me. I used 1/2" and up to about 7/8" thick materials. You may want to cut a few sample pieces at different insets and see how they behave for you (you may be surprised).