How do you cut sonotube so the end stays level? (1 Viewer)

[Frank Carter]

I'm starting the planning of my first sub soon and I've been reading all the DIY links I can. I plan on building two subs using old SVS drivers I picked up here.

I just got to thinking of how am I going to actually cut the sonotube so that the end stays nice and level? What did you guys do since it's not flat? I think this sounds stupid but I saw no mention of it any where.

If you want to share your experience or point me in the direction of an answer somewhere else, it would be greatly appreciated. Thanks

 

[Dustin B]

As usual, Patman has the answers :p)
http://www.io.com/~patman/sunosub2.html
pics 70-76

 

[James_Lyles]

I wonder if a table saw would work with a fine tooth blade?

 

[Mike Strassburg]

I measured down a little from the end to get a clean cut. Put in a screw and used a carpenter's "chalk line" to mark it. Then cut it with a circular saw, or you could use a hacksaw.

You will not get a perfect cut unless you have a big band saw, but a perfect cut isn't needed, just has to be close.

 

[Neil Joseph]

I got some fanfold printer paper and taped a section around the circumference of the tube and cut along the line. Don't know if this was the same method used by Patman.

 

[Eduardo]

I used fan fold paper too. I used a fine tooth Jig saw to cut my tube.

 

[John E Janowitz]

I actually made a jig for cutting the sonotube on the tablesaw. It's nothing fancy, but it works an you can get nice straight cuts to whatever length you need by clamping it to the table in different places. Maybe someone else has already posted about this in the past but I don't rember seeing anything. Figured some could benefit:
Regarding cutting sonotube, a local concrete supply shop has a very large table with end stops on it. Basically it is a rigged up a tablesaw that cuts sonotube very well. I have somewhat adapted their method with an attachment for my table saw. Here is a pic I made somewhat explaining it:
http://www.stryke.com/pics/sono-saw.gif
Basically you make this thing as long as you need, depending on how long your pieces need to be. You will have 3 pieces, a back stop, an endstop, and then a small piece that connects them together that you also use to clamp the attachment to the table. If you look at the pic this should make some sense I think. You can adjust where you clamp it left and right to get your appropriate lenght. You also adjust front to back depending on the diameter of the tube. I've found that having it so the tube is basically centered over the blade works best.
First, let me say this works much easier if you have a second person to help you, especially if useing long lengths of tube and large diameter. Ok, that said, you clamp the guide down, so the end stop is at the right lenght, and so your tube will be centered over the blade when resting against the back stop. Set the blade depth to about twice the thickness of the tube walls. Make sure you have a firm grip on the tube as it is light, and the saw may tend to kick it around otherwise. You turn on the saw, and slide the tube along the end stop until you hit the back stop. Then you simply rotate the tube all the way around until you have cut all the way around the tube. As long as you keep it lined up with the end stop, your ends will be perfectly straight.
I'm not guaranteeing this is the best way to do it, but it tends to give very straight cuts. If you are planning on cutting lots of sonotube, it is a good way to go.
John

 

[Vince Bray]

wrap with paper as above putting the paper over the 'good' side of the cut. shoot some spray paint to make the line, then remove the paper and cut. this gives a very good contrast to the line to aid the cut.

 

[Ron D Core]

The place you buy the sonotube should be able to cut it perfectly for you. If not there should be plenty of places willing to do it for a couple bucks.

 

[Bryan Michael]

this is a eas way level the sono tube and wrap a string around it put a string level on the string and ajust till level then mark and cut

 

[Brian Steeves]

I used the construction paper wrapped around the tube method and it worked fantastic! I used the same method when cutting the port. I used a circular saw to cut the tube. I just layed the tube on the ground and rolled the tube while cutting. Was very easy to follow the line and it made a smooth cut.
Here is the link to my site. Go to the DIY section and click on the "Silo II" link. There are detailed descriptions of how I made mine along with pictures. Good luck.