T18 Build Thread

[Chris_Allen]

Time to build a nice litte T18 with the Tang driver.

I've been building speakers out of cheap softwood ply but for this build, decided to go back to birch. What a superior wood! I forgot how much nicer it is to work with birch.

I've build the T48 and the T39 and I just can't believe how small this cab is.

It's going to be 17" internal so I end up with an 18" by 18" box. I'll probably also shamelessly steal Shawn's styling of his cab and make it look like a table.

..and the carpet needs vacc'ing...

[Chris_Allen]

Here's a shot with the 8" driver to show you how small it is:

and here it is with a 3015LF on it!

[Chris_Allen]

Just two cuts today. I'm waiting for the T-Nuts to arrive to for the baffle so I can get them glued in place.

[Chris_Allen]

I got the driver out to measure the diameter of the cut. It comes out at 175mm.

Measuring the centre point of the baffle, I got the protracter ready:

Checking the plans, I decided that cutting panel 6 was the best place to start. So I got out my angle measurer to set up the correct position, making sure that I wasn't trapping the wood between the fence:

For measuring on top of the panel, I use a steel rule to line up the blade:

I also made sure that the angled pieces didn't slide under the fence:

[miked]

Cool stuff. What will you use the "baby Tuba" for?
n/m Just read your SLA thread. Cool...almost like a really nice "computer speaker with a sub" setup? Or a mini-PA for really small events. You could put the whole thing in the front seat of any car!

I've never seen a protractor like that. Very interesting. I'm planning on buying a digital protractor for whatever cabs I build next. I know for a fact that my 0-degree setting on my TS is spot-on, but I'm suspicious if any angle cut is exactly the degree the wheel's scale says it is.

[Chris_Allen]

I thought about a digital protracter but I didn't think I needed that kind of accuracy. The T18/SLA Pro combo is going to be used as an electric drum monitor but also double up as a really portable like PA for garden parties and the like. The main consideration is where to put the speakon jacks. I'm considering putting them in the mouth of the horn to keep the other sides of the sub clean.

The T18 calls for 3/16" T-Nuts which aren't available in the UK. It's actually somewhere between M4 and M5, so I ordered TNuts of both sizes. I've had lots of fun with TNuts in the past when the nut isn't complete perpendicular to the hole. This makes getting the bolt in an absolute nightmare and when you are restricted on hand space, it's a real headache.

The M5 has some place through the bolt hole in the driver:

Having a look at the two Tnuts next to each other, the M4 looks a lot smaller:

I cut all the panels up to number 8 and had a nice pile:

At this point I released I have cut panel 7 1/2" too short and panel 6 was 1/16" too long:

Tomorrow, I'm going to check my fence alignment. I've been getting a lot of burn on some of the cuts, so I think something is pinching.

[jimbo7]

Tomorrow, I'm going to check my fence alignment. I've been getting a lot of burn on some of the cuts, so I think something is pinching.

I was getting a lot of burn and buildup on my blade on my last build. I tried a new blade and it cut like butter. Your blade might be getting dull.

[Bill Fitzmaurice]

I was getting a lot of burn and buildup on my blade on my last build. I tried a new blade and it cut like butter. Your blade might be getting dull.

+1.

[Chris_Allen]

I was getting a lot of burn and buildup on my blade on my last build. I tried a new blade and it cut like butter. Your blade might be getting dull.

I checked the fence alignment last night and it was good, so I checked out the blade. Using my untrained eyes, the teeth looked good but the table surface felt a bit rough. Over the years, the cast iron table saw top has collected bits of paint, PU and the like, so I decided it needed some TLC. I got out the wet and dry sandpaper, a bucket of water and got to it. The end result felt much smooth, a quick coat of wax on the table top and the blade and I did three more cuts. Much better!

I think I will order a new blade anyway to put in the spares cupboard as new teeth are bound to help.

[Chris_Allen]

I cut the driver hole in the baffle. No fancy tool for me, a good old fashioned jigsaw and a bit of sandpaper:

I tested pulling a tnut through by drilling a 5mm hole and turning the socket cap bolt using an Allen key. I used high quality tnuts and they pull into the birch fine:

I went round adding all the tnuts:

Drilling of the holes causing part of the ply to come away, this has created a small gap at the edge of the tnut, I'm not sure if this is going to cause a problem:

I test fitted the driver to make sure everything is ok:

I have recut panel 7 which was 1/2" to short and shaved 1/16" off panel 6, they fit well now:

and the dry fit of all panels looks ok:

Next phase is to start gluing panels 1&2, though I might actually start with panel 4, then work onto panel 2 and 1.

I've decided to glue the panels first and route out the driver cover afterwards.

[DJPhatman]

May I ask, why didn't you use Harley's epoxy/small screw trick on your T-nuts? Lots of insurance against a spun T-nut later.

[Chris_Allen]

Such is the amazing ability of my memory, I recall there be a tnut trick but couldn't remember what it was or who said it. I'll go looking for the thread, thanks.

[Jason Stromberg]

That little Tang Band woofer looks like a nice choice.

I have been using the RE audio REX8S4 with good results myself, let us know what you think when the build is completed.

[Chris_Allen]

I've been pondering over how to attach the first panel.

Following the plans, I should glue and attach at a right angle but I always use the nail gun, so this makes bracing and alignment tricky. I decided to assemble panels 1 through 4 together so I can get them square. I'll take off the excess PL, reseal the inside joints for an air tight fit, then fix them to the end panel. I've not cut the access cover yet as I plan to route it out at the end.

[Chris_Allen]

For some reason, I didn't take any pictures of the progressive gluing of the T18. So here it is with most sides in position:

There is a mild overhang between I think panels 8 and 7 just by the top of the mouth which I need to sort. The panel ended up being 1/16" too long.

Hopefully, this will stay centred!

Tomorrow, I will remove the excess glue, cut the hole for the jack plate, paint the mouth and glue on the remaining side.