Kreg Jig Mini Measurements?

[Dan Coes]

Hi All...

I purchased the Kreg Jig Mini today, planning on joining some 1" (actual thickness) hardwood stock. Is there a chart that lists jig position and depth collar information for stock with an actual thickness other than 3/4", 1/2", and 1 1/2"?.

I've spent the last hour scouring Google and these forums, and cannot for the life of me find any information about this. Without this simple information the jig is basically useless to me :(

I would drill some test holes to try and figure it out, but I'm making a table out of an old door and therefore don't have any extra wood to use for testing...

Thanks for any help you can provide!

-Dan Coes-

[KregRep]

This should be what you need, Dan! It should have came with your jig... but sometimes it gets lost along the way http://www.kregtool.com/prodImages/mini_kreg_jig_1.pdf

[Dan Coes]

Thanks - I did actually receive and read these directions. However they only tell you where to position the tool and collar for the three "standard material thicknesses" - 3/4", 1/2", 1 1/2".

As you can read in my original message, I'm apparently using a "non-standard" material thickness of 1". The manual does not tell you how to position the jig and depth collar for this material thickness. This information is nowhere to be found - not in the manual, on the Kreg site, or anywhere in the forums.

Kreg obviously knows this information, because the more expensive tools do it for you.

[Matt Thompson]

I could use this info too.  The manual only mentions three thicknesses...and I need to know the measurement for actual 1" thickness.

Anyone?

[John Schaben]

I just use a little interpolation. If it need to be flush for 3/4" material, 1/4" beyond for 1/2", I would inset it 1/4" for 1" stock and check for center. Realisticly, I think the centering  only needs to be an approximation anyway.

[Mandodad]

I checked the settings on my R3 Jig & for 1" material the collar is 3-7/8" from the bit shoulder & the jig setback is between 3/8" & 7/16".  I use my "mini" frequently for repair work & always use the settings from the R3 Jig to set it up.

[Matt Thompson]

Thanks for that info Mandodad!

[John James]

Having just taken delivery of my Mini Jig, I had the self-same question.  I emailed Kreg Customer Support, but they were unable to provide this information, which really surprised me.  So I thought I'd try to work it out.  Essentially it's a problem in trigonometry.  After taking a couple of key measurements from the jig (Kreg could not, or would not, provide these dimensions, other than the angle of the drill at 15deg), and making a couple of assumptions* based on the figures Kreg have supplied on the jig's user guide sheet, I worked out a couple of formulae.

I've knocked up a SketchUp diagram of the key measurements used, and an accompanying Excel 2003 Spreadsheet to calculate values for offset and collar settings for timber (lumber) between between 12mm-75mm thickness (and convert to Imperial measures for our US members).  The spreadsheet is attached.

Change the timber thickness using the Spin Button; the resulting offset and collar setting will be calculated.

I'd be interested in any feedback on it's accuracy, particularly as it gives a different value (-11mm) for the offset for 13mm (½in) timber compared to Kreg's -6mm.  Values for 19mm and 38mm agree with Kreg's.  Unfortunately at the time of posting I have not yet had an opportunity to test these values.

* The assumption, based on Kreg's figures, is that the depth of wood left from the bottom of the pocket to the timber face is equal to the thickness of the timber. Length of the drill guide in the jig is 70mm, and the distance from the point where the drill first hits the wood, to the face of the jig is 35.45mm.

[Ken Darga]

This 1-1/2" coarse thread, #2 square drive washer head screw works well in 1" thick, softer material.

[John James]

I've tried using the 1½" coarse #2 Kreg screws on the logstore I'm building, which is (over-engineered?) in 1" Western Red Cedar throughout.  Have to say I've been disappointed with them in this project - they are quite thin, and consequently are very easy to over-screw in the cedar, causing them to spin and lose grip, even with my driver on its lowest torque and speed settings.  I reverted to Turbogold 4.5 x 45mm (1¾"), and find they work far better (for me, at least).

The Mini Jig is good, though, and I've also been using the jig setting for 1" to 1" calculated in my spreadsheet above (11mm jig offset, 95mm collar), and find it works well.

[Ken Darga]

John,

Cedar is a very soft wood material.

Installing screws in cedar, will strip-out, when over-torqued. 

I'd recommend installing the screws in ''cedar'', using a hand-held-driver, 

ease into it---

don't over-torque it---

just snug-it-up,

and followed by 1/4 turn of the driver.

Some power-drivers, even on a ''low'', or lowest torque setting, may provide to much torque, for some applications.

Make test specimens on sample pieces, before proceeding to the finished product.

What is your power-drivers ''output torque'', (''in-lbs of torque''), at it's lowest setting?

The users manual may provide that info. If not, contact the OEM.

All fasteners have ''torque limitations'', for the applicable material, pilot hole size, etc.

Make an ''output torque'' chart, for each setting, and affix it to your power-driver.  (Very helpful for future uses, when it's needed).  A chart as simple as file card stock, with the markings noted, cut-to-size, and affixed to the machine, (using transparent packaging tape, or the like).

It's also beneficial to have a drill-speed chart, for power drilling tools.

''Engraved'' markings can be added, in a suitable location, right on the drill case housing.

Very handy to have the markings, for an ''at-the-ready'' reference use, for some applications. 

(A Dremel power engraver is a very handy tool, for this purpose.  The adjustable stroke feature allows for engraving onto a variety to materials).

[John James]

@Ken Darga, thanks for the helpful advice.  I might have done a smaller project by hand, but this has so many screws (and intermittent carpal tunnel syndrome doesn't help) so driving the larger screw instead worked for me.

[Ken Darga]

John,

There are small right angle ratcheting type hex drivers, on the market.

Some models include a variety of tips.

The 1/4'' hex fits Kregs square-drive bit perfectly.

The tool handle length is only about 4'' long and has a reversing feature---very useful tool, for many small tasks.

It makes for easier installation, over a screw-driver type handle, for many application/uses.