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Charles Jenkinson wrote:All stapled up. My wife thinks it would make a nice lamp shade.

It wouldn't look out of place in a finnish sauna

Seriously, looking very good. And great to have a helper like that.

Finally got into the garage again, and put the mouth side sheaths in. They are stapled toward the front. I'm not sufficiently flush with big clamps that would reach the depth of the cabinet, so staples it was.

Here's how not to do it. My fillet faux pas. Bad idea to use expanding adhesive to make a fillet. Need to use a different substance. not sure what yet.

Charles Jenkinson wrote:Here's how not to do it. My fillet faux pas. Bad idea to use expanding adhesive to make a fillet. Need to use a different substance. not sure what yet.

It works just fine, in appropriate quantity.

Charles Jenkinson wrote:Bad idea to use expanding adhesive to make a fillet. Need to use a different substance. not sure what yet.

The trick is not to try and smooth it down with fingers AT ALL! Wait 12 hrs, then trim with a box cutter and/or sharp chisel. You can also prepare the curved syrface by applying maksing tape, but I found this wasn't really worth the effort.

Apply - do nothing, then trim in 12 hours. DON'T use any other types of glue!

Ok. I'll cut off the mess I have made, and put one healthy bead down as a 'fillet', and then leave it till tomorrow. This feels counter intuitive in terms of it doesnt feel like its going to give a neat radiused fillet.

Charles Jenkinson wrote:Ok. I'll cut off the mess I have made, and put one healthy bead down as a 'fillet', and then leave it till tomorrow. This feels counter intuitive in terms of it doesnt feel like its going to give a neat radiused fillet.

Why do you think you need to make a fillet? Is it purely out of cosmetic reasons you want it?

The PL expands into the plywood and thus making an airtight seal. And since the PL is so strong, you don't need a fillet to make a strong bond.

Yes, I think the fillets would be for cosmetic reasons. The concept of radiused fillet comes from two areas; my background in engineering, and making stitch and glue boats using epoxy resin, where the fillets are glass-sheathed afterwards so a good blend is necessary.

I would imagine I don't particularly need a fillet for strength or air tightness, but at the same time wouldn't presume air tightness and would do the test.

Cutting through the air bubbles in the curing PL when dressing off the glued seams at the top and bottom of the sheaths leaves an uneven finish. I'm guessing these are just re-filled with PL to be dressed again at another stage.

As for the radiused fillet, do people not bother doing them, or find that they can achieve them with PL? My take is either caulking or thickened epoxy. I've found the polyester car filler (bondo?) doesn't stick well to wood.

The other point is I could be getting anal, and duratex sorts all this out....

Charles Jenkinson wrote: The other point is I could be getting anal, and duratex sorts all this out....

Now you've got it figured out...

I on the other hand did somewhat of a fillet. I say somewhat because I rubber gloved and used to finger to "press in" the PL along that joint to assure a better seal. Truth be told, i just made sure I had enough on the backside so the squeezout would be mostly on the inside.

I know the plans say not to do that, but I did. Leftover anality from my plumbing days.

Shouldn't have mattered in any case because I put a cover/grill on anyway.

Charles Jenkinson wrote:Yes, I think the fillets would be for cosmetic reasons.

As for the radiused fillet, do people not bother doing them, or find that they can achieve them with PL? ..

Yes, I have done just that - radiused fillets on my latest J112 Lites. I cut the PL out as I described above ( after 12 hrs ) and used MSS ( modified silicone sealant ) for the fillet. This was AFTER I sanded the curve and the flat surfaces.

The one thing you have to be careful about is to wait for full cure of the PL ( at least 24 hrs ) before applying the MS as any moisture in the MS may casue the PL to bubble a bit - which it did on my first attempt.

An update.

I tried a water-based caulk fillet, but didn’t like the look and feel of it (perhaps down to my technique), so I scraped it off and did some epoxy fillets. Will post a picture some time. However, I’ve just been totting up the expenditure so far, given that I have more buying, planning and thinking time than actual building time, and I’m only a few items short now. So, here’s the list of my UK costs for building a pair of Jack 12 lites:

350 - Eminence 3012HO’s (Blue Aran. They have them at 150/ea at the moment on ‘price match’ for any imminent buyers!)
60 – BB plywood (local supplier)
30 – tilting top hats (Blue aran)
15 – baffle mesh (Robinson wire cloth)
45 – Tuff Cab paint, rubber feet, 3 textured rollers (Blue Aran)
218 – speaker hardware (40 tweets, crossover parts, PL, spring handles, screws, front grill mesh, plastic corners, cast top hats, & delivery)
50 – Customs and excise import duty on speaker hardware stuff (assumption, can’t remember exact cost)
3 – foam balls
6 – ABS cement
15 – other screws

Guesses on stuff not yet bought:
30 - Front mesh for over tweeters (from speakergrillsuk)
15 – pillow stuffing
40 – acoustic foam

Total: £877 for a pair.

This has been spread over 18 months. Numerous minor items are redundant due to changes or buying more than required. I do wonder what the UK retail cost would be, but it’s slightly irrelevant – I think of it more as cost-effective therapy.

Charles Jenkinson wrote:
Total: £877 for a pair.

$NZ 1,710.00 WOW! ...and I thought NZ was the most expensive place to buy stuff for Jacks.

But, relatively speaking, you've got very nice cabs for a fraction of the price you'd pay for a commercial equivalent that is as efficient,as light and as nice sounding as the Jacks. And the therapy was chucked in.

Charles Jenkinson wrote:An update.
So, here’s the list of my UK costs for building a pair of Jack 12 lites:
<big list>
This has been spread over 18 months. ... I do wonder what the UK retail cost would be, but it’s slightly irrelevant – I think of it more as cost-effective therapy.

Therapy is quite cheap then, isn't it? Sometimes that's not factored in.

Charles:
Are you telling me a pillow is 15 quid?