Need advice on building my cab

[ranma]

Ok, I'm not really a woodworker, so this would be my first real job at wood working. Nonetheless I think I can do a good job if I go slow and take al the advice I can from the forums, so here I go with my first questions I didn't find an answer to... 

1. How do I make clean junctions between two pieces of wood that connect at an angle different than 90 degrees?, for example the roof of the cab (angle 30 degrees for example) with the pirce of wood on the back of the cab (vertical to the floor).

2. How do I round the inner and outer corners of the side panels in a precise way?, is there a tool for such task?

3. What kind of screw should I use if the way I want to build the cab is by screwing from the inside using square wood sticks to fasten the corners of the machine. I mean, how deep should it go into the MDF?, how thick should the screw be?

That's all for now, I hope I made myself clear on my explanations.
Thanks,

Francisco

[shredso]

I think I can answer some of your questions.

1. The angle on my cabinet top is 45 degrees.  I cut this with a table saw, but you could also set a 45 (or other angle) on a circular or jig saw.  45 degrees works well because 2 45's make a 90.  If you were to do an odd angle like 30, you would need a protractor.

2.  I think a router with a round over bit is what you are looking for.  You could also sand the edges or a lot of people use T-molding. 

3.  I'm using 2" coarse thread drywall screws through a 2x2 wood stick as you described also with wood glue.  1 1/2" through the 2x2 and 3/4" MDF.  If you were using a different size bracing, or a different size mdf, you may want a different size screw.  make sure you pre drill the holes.

[Blanka]

With a normal sawing table you can set every angle with ease. Your cab gets much more solid when all faces join nice.
You can screw from the inside with normal philips screws. Just go about 3/4 of the thickness of the MDF deep.

[ranma]

Ok, answer 3 is clear, and I will use glue also, I forgot to mention it. Thanks to both of you.

As for the others, let's see if I can explain myself with some pictures. Sorry if don't speak in proper terms, but woodworking isn't my speciality and english is not my native language, bad combination I guess, hehe...

Question 1: I mean if I wanted to do something like the picture.


How can I match the borders of the two panels that make the back and "roof" of the cab in that precise way?, is there some kind of tool for that?, I can't imagine how to do it with a table saw.

Question 2:
I already got t-moldings, so that's no problem. I meant, since the side panels have a profile with various angles, I'd like them to be rounded angles instead of hard ones. In the same picture above, I would like to have the angle in the orange part to be rounded instead and to join the two sides in an uniform way.

[Blanka]

Sure you can do that.

See the wheel below the table? Use it to put your blade anywhere between 0 and 45 degrees.

[sstorkel]

Question 1: I mean if I wanted to do something like the picture.


How can I match the borders of the two panels that make the back and "roof" of the cab in that precise way?, is there some kind of tool for that?, I can't imagine how to do it with a table saw.

FYI, I fixed your IMG tag. The 'width' and 'height' arguments aren't necessary or don't work with our forum software.

In general, if you have two pieces of wood that meet to form a certain angle you make beveled cuts on each piece. Say, for example, that the top of the cabinet meets the back at a 130-degree angle. You tilt the blade of your saw to 65-degrees (130/2) and make a cut along each of the pieces that are supposed to meet. You can make the cuts with a table saw or circular saw.

Question 2:
I already got t-moldings, so that's no problem. I meant, since the side panels have a profile with various angles, I'd like them to be rounded angles instead of hard ones. In the same picture above, I would like to have the angle in the orange part to be rounded instead and to join the two sides in an uniform way.

Still not quite sure what you're asking here... In general, you can create rounded shapes using: a jigsaw, a router with a round-over bit, or sanding. Which one you pick depends on exactly which type of rounding you want to do. Do some reading on each of these three tools and you should be able to figure it out.

[javeryh]

Question 2:
I already got t-moldings, so that's no problem. I meant, since the side panels have a profile with various angles, I'd like them to be rounded angles instead of hard ones. In the same picture above, I would like to have the angle in the orange part to be rounded instead and to join the two sides in an uniform way.

Still not quite sure what you're asking here... In general, you can create rounded shapes using: a jigsaw, a router with a round-over bit, or sanding. Which one you pick depends on exactly which type of rounding you want to do. Do some reading on each of these three tools and you should be able to figure it out.

My best guess would be he is trying to figure out how to cut an accurate curve out of a piece of plywood - like the top of a Ms. Pac-Man or something.  If that is the case, you can use a jigsaw and cut to about 1/8" outside of the line and then sand to the line to get a perfect curve.  Don't forget to use a router and pattern cutting bit to make an exact match for the other side panel!

[ranma]

Ok, thank you all, now I've figured out everything. I actually didn't know I could do that kind of thing with the circular saw, just because I've never used the one I got at home, hehe... just a look at it would have helped... 

About the question 2, yes, I was refering to what javeryh says. Like the corners in this picture:
http://www.silverplanet.biz/image001.jpg (linking since the last picture I used img tags were fine in the preview but not in the actual post)

I though there was some kind of guide for the router or something that could help round corners in a precise way.

[sstorkel]

Ok, thank you all, now I've figured out everything. I actually didn't know I could do that kind of thing with the circular saw, just because I've never used the one I got at home, hehe... just a look at it would have helped... 

If you don't know how to use a sawboard, be sure and read the "saw board" sticky thread at the top of this forum. It will save you a lot of trouble!

About the question 2, yes, I was refering to what javeryh says. Like the corners in this picture:
http://www.silverplanet.biz/image001.jpg (linking since the last picture I used img tags were fine in the preview but not in the actual post)

I though there was some kind of guide for the router or something that could help round corners in a precise way.

Routers are good at making exact copies of things. You tape or nail the original (a.k.a. "template") on top of a piece of wood, install a template cutting bit in the router, then run the router around the template. When you're done, the piece of wood on the bottom will be an exact duplicate of the piece of wood on the top.

In the case of these rounded corners, the technique mentioned by javeryh is probably the quickest way: you draw the curves out on your wood (trace a coffee can or some other round object), cut close to the line with a jigsaw, then sand until the line just disappears. I wouldn't leave an 1/8th of an inch though; it'll take you forever to sand it  away! Get as close as you can with the jigsaw, but don't cut over the line! You should be able to get within 1/16" and you can can that away by hand pretty quickly.

[ranma]

That's great, thanks for the advice!