Jack 112 Lite, (x2)

[kekani]

Okay, venturing into an area I haven't seen yet, and that is the Jack 112L. I did the same thing with these plans that I did with the previous 2 builds (Jack 112 and Wedgehorn 6), which is I unintentionally visualized and mentalized the build on a daily (dare I say, hourly) basis. I remember doing this when I first built my `ukulele.

This thread is probably going to be more real time than the others (where I took a bunch of pics and posted later).

First impressions of the plans: Definitely glad I got tools. Haven't seen much use for the sliding miter saw like the Wedgehorn 6, but the table saw and router (in the table) is put to good use. I don't want to say this is not for the meek, as Bill incorporates some play in the build. As with the other builds, I've changed a few process to suit me. I'm not saying this is THE way to do it, its just the way I find I need to do it to give me confidence to complete a good build.

Caveat: This thread will probably mean nothing to anyone if you don't have the plans in front of you. Completely different from the non-Lite version. Then again, if you know how Bill designs his plans, you can figure out the process - again, just trying to help others (if its possible), and get help myself.

Starting at the beginning, I still get a kick out of the full sheet of bending poplar curled over in the truck bed.


Milled down, all straight cuts. Still need to trim to exact size, which I've done as of this post. There's one angle I forgot about, which you'll see. Note: Painted Wedgehorns in holding pattern.


I bought a full sheet of 1/4" MDF a while ago from the scrap pile to make template. It is getting good use here, and I'd do it again if I had to (was only $10). Here's the circle template for the side braces.
Detour: I cut out a rectangle for the outside dimensions of the side braces, my concern was my ability to keep the straight edges square.


Using the router table as a circle cutter again, the 1/8" bit is very specific for this cut. I'll use the outside cutoff later as a template for another piece.


Not even sure if you can see this, but following the plans, I drew out the bottom and top.


Here's how I got the radius for the horn braces. You can see the cutout for my horn brace template.


Here is the horn brace template stapled to my circle template. It'll be pattern cut for the proper brace radius. Yes, a template to make a template. In this build, I think the templates are the MVT.


-Aaron

[Dan30]

Very cool. I wonder where these come in on the difficulty scale.

[Grant Bunter]

Very cool. I wonder where these come in on the difficulty scale.

Jacks = 3
Jack lites = 7

[mikell128]

Awesome. I've been hoping someone would do a jacklite so I can watch. It's made me want to build one myself just to see how the process is different. Looking forward to your progress!

[kekani]

Okay, back in the shop today, after cleaning it out and throwing away (giving away) all of my old jigs and stuff for building `ukulele (and bass). Unfortunately, there was another project I had to side step and complete, for my brother.

I believe things happen for a reason, and there must be a reason I found this site, at this time. My brother asks me to make him a "Rogue" style Plyo Box (google it, he's the athlete now that I once was, sort of). And of course, I have 3/4" ply (for my jigs), and now I have a plate jointer (acquired when doing my Jack), and what is the KEY ingredient in putting this all together? PL adhesive. If I had never been here, I would never had a need to even look at adhesives in a tube, much less use it on my brother's box. I can't even imagine what it would be like putting it together with a bottle of Titebond from my refrigerator.

Anyway, back to the build, here is the brace template, on a brace blank. Not sure why this happened for any reason, but my POS little bandsaw lost its bottom tire, and I had to go to Joint Base Pearl Harbor/ Hickam to use the wood shop. Guess what, their bandsaw was down as well! Why do things like this happen? Well, I don't have any parts ordered yet, that's probably why. Anyway, a drill press, scroll saw and 1 hour later (which should've taken me no more than 20 minutes including cleanup) I was on my way, with the braces cut close (as well as some other parts). You can pretty much tell where we go from here, template route to size, and cut the triangle piece out on the resaw (don't throw it away). BTW, this is a detour - I wanted to have the bottom and height square, so I knew I was going to used a template to trim these out. We'll get back to the braces later.


Remember the offcut from the circle, well here is it used as a template to draw out the duct plate.


Here's another, smaller circle template, that I'm going to use the radius to make another template for the throat sheath braces. As a side note, the duct plate blanks were not in my original milled wood pic (neither was a whole bunch of other stuff I found out).


Throat brace template stapled to the circle template. Another blank throat brace on top just to show that I'm going to cut the brace template a little short. The plan has it a little long, designed to shave it off once its glued in. I just as soon take off the 1/32" or so (less) right now.


Here the throat brace template is where it should end up, no trimming needed.


If you wonder why a lot of my pics is on the table saw, its because my bench is full with other stuff. Besides, I use the fence on the table saw to square everything up, especially templates to blanks. Here's the throat braces, with the bottom duct plate.


Now that the duct plates are trimmed, time to template them to size, with the offcut from the big circle. Used more than one when I could.


My friend decided instead of cutting my baffle template on his laser, a trip through Korea to Thailand was more important. So, even though this looks ridiculous, one advantage of having square offcuts, means I can use them as a template guide (this is where the scroll saw REALLY came in handy>


Of course, once the first baffle was done, that was used as a template for the other baffle. Not saying how long the first one took, but the second one took all of a minute and a half. . .


I KNEW I was missing some parts from my milling day. Here's some familiar parts, and some not so familiar (for Jack builders). Change that, I was missing a LOT of parts. And I still need to make the woofer spacer and phase plug extension (foam will hopefully save me).


I said it before, the Most Valuable Tool for this build were the templates.
I feel like throwing them away (which I will after I'm done), along with some other scraps.


I'd be lying if I said I wasn't eager to start gluing so I did the bottom. Then I just finished up the other pieces ( tops and bottoms). The brace spacing jig is a leftover measuring stick - used the Center Finding ruler a Lot, but when it came time to mark lines, this scrap stick with a mark at 10" sped things up a LOT.


Aaron

[kekani]

Note to self: Write out a complete cut list so when you have to do a large piece like the driver spacer, you don't have to glue up off cuts. Of course, this is probably why Bill describes a way to join two panels to make a larger piece. Here is 1/4" BB being doubled up for the spacer, as well as the phase plug extension. Yes, the piece on the left with the cutout is going to be cut off in the final piece (octagon on the outside). Its at this point I'm really realizing the benefit of the stapler.


In my zeal to get the bracing glued, I failed to make the hole for the top hat. Yes, template again. For you left brainers out there, I did the math. . . took an outside measurement with a micrometer (1.585"), divided by 2 for the radius, and converted that to my custom circle cutter of the laminate trimmer edge guide/circle cutter. Initially, I bought this Grizzly trimmer to do only 1 thing (well, two), and that is route the rosette channel in the `ukulele and cut the soundhole. Anyway, I made a template of the circle (tophat), drilled out a hole with a Forstner in the bottoms and throat plates, and pattern routed to the edge. You can see the laminate trimmer with the edge guide/circle cutter turned backwards (had to lengthen the slot, and drill another hole for the pin). Tophat holes are done in both bottoms, and the lower throat brace.


More math. In order to pin the brace from the outside, I decided to make up spacer templates, which will serve 2 purposes. The first purpose, I'm laying out the markings for where the side braces will be once they're glued in. The markings go on both the throat/mouth piece, as well as the sides - shoot above the line, hit the brace inside. That's the plan anyway. The second purpose we'll see later - used to actually space out the bracing on the inside when gluing up. That's the plan anyway. It came out close, just under 1/32" too long.


Here's the marking on the outside of the sides, where the line only goes where the brace actually touches.


How did I get to this point? Followed the plan, exactly. I didn't see how it would keep everything square, but it (the plan) does. Obviously, we're working from the bottom up, with the top going on last. Pretty neat how the plan squares it up - it works!


And then there were two. I made the back almost to the exact dimension of the box (not the plan) and used it to help square it up. Didn't really need it. Also test fitting the top hat and the lower throat plate.


While its drying, I need to start finishing up my Wedgehorn 6's, so a little pause for a bit.

-Aaron

[67baja]

Great job on your builds. It is really helpful the way you describe what we are looking at in the pics. It is all very much appreciated!

[LelandCrooks]

Probably one of the most technically thought out builds I've seen. Nice work.

[Philip Kelley]

MUST stop looking at this build thread now.

I've got a pair of J110s that I built last year, and absolutely love'em, but these Jack Lites are just too cool. What a fun project!

[bassmonster]

Great work! You are one of the first three Jack Lite builders ever I think, Bill being first of course.

[Harley]

Now if your workshop's as tidy as your parts piles, you might just be in for a reward kekani. However pics are a must

[kekani]

Now if your workshop's as tidy as your parts piles, you might just be in for a reward kekani. However pics are a must

My workshop is my garage, with bicycles, martial arts bags, a stack of wood stickered on the floor - no vehicles. Hence, no pics. Actually, my bench stays fairly organized, except now when I'm making cabs. . .sheer size of parts take over.

And, being first is not always best. I'd be doing another pair of Jack 112's had Bill not come out with the Lite. My current 112 is 34lbs. So I'm looking at possibly dropping it to around 27lbs with these. More pics to come (Wedgehorns are being glued right now).

[kekani]

Preparing to glue in the horn braces - guide w/ wax paper clamped in, & the bracing dry fit. You can see where the previous pics of the spacers and the marked lines will come into play.
P

I had a real problem visualizing the gluing of the horn braces. The brace jig(s) helped a lot. If I failed to mention it, jigs and templates go hand in hand with this build. By the way, this was a really easy glue up, even if the spacers were not "solid", meaning, it's just 6 pieces of scrap wood, cut to size. It went so fast, I found it easier to put glue on the 3 braces at one time, then just place the spacer, brace, nail, nail, nail, spacer, brace, nail, nail, nail, etc.


Rubber meeting the road. . .this is the dry fit to set the guides clamped to the baffle. You may be able to make out the lines on the horn that tells me where to nail (above the line, hit the brace, that's the plan).


I must admit, I was thinking of making a complete inside jig to do this glue up (instead of brads). Followed the plan process of nailing and bending. . . overkill on the brads, but it ain't going anywhere. It was easier to nail with the cab on its side. Glad I got the heavy duty brads with the larger head - I think the light duty would pull out. I also cut the horn larger than plan (read: sized to fit with no gap) on the verticle measurement. There needs to be overhang to cut off later; this helps in the glue up process.


Left to cure face down. Even with 4 clamps inside, this thing is light.


Rookie mistake: I searched and searched for the braces to glue up, only to realize that I'm not smarter than a fifth grader. Question, if you need 10 braces per cab, and you build 2 cabs, how many braces do you need? Answer, "I'll make 1 extra for a total of 11." Good thing I didn't fly the templates.

Thoughts at this point: it took a while to cut the parts, especially since I template routed. However, the time it took to mill parts manifested itself in the glue up so far, which is fast compared to the "normal" Jack.
It's also square, without biscuits.
Don't mistake fast for easy. I'm mentally exhausted. Could be I'm working on Wedgehorns at the same time that's taking a toll.
By the way, there's a LOT of parts. Still got more to cut, specifically the back flanges, tweeter array supports, and frame for grill cloth ( haven't figured out how I'm going to do that one just yet).

-Aaron

[Bill Fitzmaurice]

Glad I got the heavy duty brads with the larger head - I think the light duty would pull out.

The plans call for 1/4" wide staples on the 1/8" parts.

[kekani]

The plans call for 1/4" wide staples on the 1/8" parts.

Another reason why it's not good to be first. And why there is much value to this forum- great guidance.

Actually, my POS stapler/nailer is really bad with the accuracy of the staples; nailing being MUCH more accurate. I figured I had about 1/8th" leeway to hit the brace in the center, so I went for accuracy. I would/should definitely switch back to staples for the edge of the horn. Definitely know what I'm doing we the throats sheath.

-Aaron