I have decided to build one Skram. But I am wondering if anyone have tried to modify the built to fit an 18" driver? 

Second: have anyone used an 18" for the original design? 

What was your experience with building them? We're the cuts manageable? I see parts of the assembly where it will be very tough if not impossible to screw the part together. 

Quality will always come at a price. You can go for cheap china stuff, but in my own experience you will always regret it in the long run.

If you have router to do housings/dados/grooves for all the panels and braces, you can assemble without screws. Just use clamps and ratchet straps to push everyhing together. Screws are obly needed to hold the panels in place until the glue has set. Once the glue is dry, and provided that the gllued surfaces have been joined well enough without any gaps, the glue joint is stronger than the wood itself. 

A dadoed joint will have even more glue surface and be yet stronger. The only challenge is to be precise. If the dadoes don't line up, you have a problem. 

Check out for example JulianDAs thread about his 15" front loaded horn, many diy builders nowadays take their time to prepare their builds, they do a dry-fit before glue and final assembly, to make sure everything is spot on.

I have been looking for cnc plans for the Skram, but haven't considered that the dado joints could be done with a router. 

But as you mention you would have to be precise for this to work. With some thorough drawings, and being a bit conservative when doing the carving it could be done. Interesting. 

Have you tried to use a router on some of your own projects?

Awesome, thanks for the suggestion. Dry-fit is definitely a good idea.  

You can build router templates or guides to make it easier. It pays off especially if you plan to build more of the same cabinets later. A well laid out straight router guide can be quite versatile. You can build one easily from plywood, for example offcuts. If you think about it beforehand, depending on your wood supplier, if you can be present when they cut, you can ask the operator to saw a certain way to get suitable long pieces. For example if he will cut several pieces of the same width, he will probably do a rip cut the whole lenght of the sheet to establish the correct width.

Depending on the company's policy, and the mood of the operator, you might get lucky and get permission to take a few extra scraps. 

It can get expensive (or you should know a 'guy') with cnc. If you say you are good at woodworking, I see not problem why you can't build it by yourself. You need a tablesaw and a router. Most important thing to make it nice is some templates for handles, m20 polemount etc. 

A rail saw makes more sense unless you have dedicated workshop space and big money for high quality tablesaw.

My only concern when doing the dado joint is how to fit those to the cut plans that Ricci has provided. How am I going to take into account that some of the cuts will have to be smaller? 

Or is that already in the cut plan? Or was the the original build meant to be assembled with screw? 

It depends mostly on your tops/mids.

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Agreed, the Skram is much better than a Tham in this area, just look at the graphs on Martinsons site.

I have two 12" drivers that I want to give a purpose. But I will find that elsewhere.