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Modifying the Kreg Pocket Hole Jig

23K views 25 replies 12 participants last post by  MT Stringer  
#1 ·
Some of you have probably seen my Pocket Hole jig set up (pics shown below). It works great. I have drilled hundreds of pocket holes with it. But, therein lies a problem. When I am drilling holes in panels such as plywood cabinet members, I have difficulty reaching around or over the panel to operate the clamp. In fact, on more than one occasion, I have scraped my arm. That is not good for a guy with thin blood.

So, in the words of Tim, The Tool Man Taylor “So I rewired it!” :)

I know what you are thinking – A new model has just come out with the handle on the users side of the jig. I didn’t want to buy a new jig when I have a good one already. It just needs to be Mikeyized! :)

My plan is to mount an air cylinder on my current setup that is actuated pneumatically by a foot operated switch.

Since the next step up from the manual jig is the Kreg Foreman ($849), I should be able to accomplish my modification for under $100 or maybe a little more.
My next round of building cabinets for our kitchen should be a lot smoother and make me a lot more productive.

Something I had on hand is a piece of 1/4 inch aluminum plate 3 inches wide x 12 inches long. I decided to mount the cylinder on it. But first, I made an exact duplicate out of 1/4 inch mdf so I could figure out how and where to mount everything.

After removing the clamp mechanism that came with the jig, I commenced to measure and drill mounting holes in the mdf. Then I transferred the holes to the aluminum plate by simply drilling through the holes in the mdf.

I don’t have a picture, but I used the original nuts that were used to secure the clamp. I used JB Weld epoxy to permanently mount them in the sockets underneath the jig.

I countersunk the heads of the mounting screws for the front and back cylinder mounts.

With everything fitted and working, I decided it was time for a new sled to mount the jig on. So, I recycled a piece of 3/4 inch plywood I have had since the mid 80’s. It was originally a box that pump parts had been shipped in and I salvaged it from the dumpster at work. Now it has a new life. Unfortunately, it wasn’t big enough so I added rear deck by gluing on a piece of maple. Once everything was dry, I added an edge all around and ran it through the drum sander until I had two smooth sides. I also needed new extensions for each side of the jig so longer material can be supported so I glued up two pieces of 1/2 inch Baltic birch. That turned out nice.

Final assembly and overview

Time to get this project wrapped up.
I covered the plywood deck with white Formica as well as the material supports and the rear support for the cylinder. After trimming the laminate flush with the plywood, I used a chamfer bit to bevel the edges slightly.

The original four 10-24×1 inch machine screws secure the front of the plate. Two 1/4 -20×1 inch round knobs attach the rear of the plate to the sled. If necessary, I can remove the cylinder as a unit.

And now for the good part. If something breaks, I can simply remove the four screws and the two 1/4 inch round knobs, remove the air cylinder unit and replace it with the original clamp!!! :)

But wait, there is more!

If I need to drill pocket holes in 2x lumber, I will have to reposition the air cylinder. To do that, I simply remove the four 10-24 machine screws which will free up the sled. Then I will need to remove the four wood screws on the bottom side of the sled which keep the rear cylinder support in place. After determining the position for the cylinder, put the screws back in the aluminum plate, and drill new screw holes on the underside of the sled so the rear support will stay put. No need to remove the two 1/4 – 20 round knobs.

I drilled a few holes and the jig is working great. I had the air compressor set at 80 psi. I think I can easily reduce it to 60 psi.

The only thing left is to get a filter for the air line. The specs call for a 40 micron filter. HF has one that should work just fine.

I hope you enjoyed reading about this build as much as I did building it.
Mike
 

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#2 ·
Holy crap Batman.. a pneumatic, foot actuated clamp. Now that has to be one of the coolest mods I've seen done to a Kreg rig. No doubt that this will be a very popular upgrade for alot of guys.

Outstanding!!!

bill
 
#3 ·
Nice job Mike. One question: that looks like a double acting cylinder. Is it, and if it is, why do you go with that instead of a single acting with spring return?
 
#5 · (Edited)
Thanks for the kudos.
@Chuck - yes it is double acting. When I started this project, I had little to go on, so that is what I bought. And the foot switch works well with it. I think a single acting cylinder would be OK if it has a spring to retract the piston.

If I was to do it again, I would prolly go with a smaller cylinder...maybe 1 1/2 inch bore instead of the 2 incher. The stroke is only one inch but that seems to be OK.

Yeah, I am a member on the Kreg Jig Owners forum. I don't know how well it would be received to post a jig that has been modified. I will browse around and see if others have posted anything similar. Personally, I haven't found anything on the internet like this. I have seem some shop made mods using wood but not pneumatically operated.
 
#7 ·
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#8 · (Edited)
Nice job Mike :)

Kreg will not have it on the market place would make it to high in price but if I recall they have one that's on the front side of the fixture.it may not be Kreg but some has one out in the market place for the short arm guys,, :)

Kreg - Home

Kreg K5 Jig Pocket-Hole Jig System

>>>>>
 

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#10 · (Edited)
I checked the new K5 out a couple weeks ago and to be honest, wasn't too terribly impressed with the "new" unit. No doubt it will maintain the standards we've come to expect but IMHO the new stuff has added to the jig just for the sake of putting a new version out on the market. I can't speak to the clamping mechanism since I didn't get to use the thing. I can't see it lasting long in a production type atmosphere. The little handy dandy tool holders are nice, just would have like to seem em a little sturdier. The ratcheting clamp may be the nicest new feature of em all. If it works as advertised and holds up. The set up block looked handy...
 
#15 ·
#16 ·
I see your photographic knowledge came into play.

Well lit shop.

In focus.

No hairy arms hiding the subject, LOL.

Also, I see that you used a corded drill. I, also, normally will not use a battery drill for tasks like that. Screwing in maybe, but not drilling.

Good video, Mike.
 
#17 · (Edited)
Ok just watched the video and I believe I now know what a pocket hole is .
Mike I can see where you can save mega amounts of time with your clamping system ! That is quite ingenious really. You missed your calling as you should have been an engineer !
I was waiting for you to get your pinky squashed there though :shout:
 
#19 · (Edited)
Had to watch it again as I really find that air cylinder fascinating . I'm easily amused I guess .
Gotta make me one of those . I love the sound for some reason when it's actuated lol.
The drilling looks like it would be quite a task for a cordless drill . I'm assuming the jig doesn't get damaged from the drill bit?

Ok just found a video on YouTube . I see that kreg thing at WindsorPlywood all the time and didn't know what it's purpose was . Looks like a must have item to me now
 
#21 · (Edited)
Well I'm going to buy one of those jigs this week . Not going to implement the air just yet though lol .
Probably have a hard time sourcing the parts anyways

I went to lordco to get a decent 50' air hose made and it was over $400 :(
 
#22 ·
Well I'm going to buy one of those jigs this week . Not going to implement the air just yet though lol .
Probably have a hard time sourcing the parts anyways
The newest model Kreg jig has the handle on the operators side. I don't know how it is made so I can't comment. My jig was the previous model and only four screws held it to the basic frame. Easy to remove or put back if the air cylinder were to fail.

Rick, I hate to show you this website because it may stimulate all sorts of ideas. But here is a pretty informative webesite that has everything you might need. Their videos describe the function of the air cylinder.

Pneumatics - FrightProps.com

Air cylinder
rear mounting bracket
front mounting bracket
rubber bumper and extension shaft
muffler for the footswitch.

The foot switch came from ebay. I could probably check my history and figure out where I got it.
 
#24 · (Edited)
I found an aluminium version of the 4 at HF. I have been impressed with its quality and its price was really good.

I have not done a lot of pocket jointery but it has been a handy way to work for some projects. That reminds me, I need to get more screws.
 
#26 ·
That's just too cool!! WOW, all I can say about that. I'd like to do that to my own jig. I don't know if you mentioned it or not, where did you get the foot switch and the other parts from?
Ebay -
4 way pneumatic foot pedal operated valve 1/4" NPT SHIPS FROM USA

Rear mounting bracket -
Bimba D 620 Cylinder Pivot Bracket New | eBay

Bimba dual acting cylinder
UP TO 7 NEW BIMBA 1" STROKE STAINLESS AIR CYLINDER 311-DXP

The parts listed above came from the seller "dockguys"

But, I think you can source everything from Freightprops.com. That is where I got the front mount and plunger.

It sure made life easier while I was building our kitchen cabinets.