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PastorPaul
11-21-2003, 12:03 AM
I should be ready to start hanging the stringers for my wheelchair ramp tomorrow. Getting the top cut should be pretty easy. It's just a matter of clamping the 2x6 along the ramp line, and using a short piece of nice straight 2x4 or 2x6 against the joist, I'll get the cut line I need.

The problem is knowing how to cut the stringers at the bottom. When I get to the end of the 18' ramp, the stringer has to be down to nothing so that last deck board will be as close to the sidewalk level as possible.

So how do I determine that lower cut? I would like to finish this tomorrow - Saturday at the latest - because the St. Louis TV station has rain and winter weather coming in Saturday night and probably through Monday.

Pastor Paul
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Cody Colston
11-21-2003, 09:14 AM
PP,

The easiest way is to use a framing square. Hold it with the short side of the square in your right hand, pointing up. This is the rise. Hold the long side in your left hand (it will be horizontal)this is the run.

Set the rise and run dimensions on the square at the bottom of the stringer and mark for your cuts. On the top end, mark along the short side for the plumb cut. On the bottom end, mark along the long side of the square for the level cut.

You can use a couple of c-clamps to maintain the rise and run settings on the framing square or the little brass clips if you have some.

Cody


What isn't tried won't work

PastorPaul
11-21-2003, 11:11 AM
Cody,

There really won't be a rise at the bottom, will there? At that point the stringer should taper to a point.

Pastor Paul
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PastorPaul
11-21-2003, 02:02 PM
Jon

Your picture didn't come through. Try again and I'll come back later to check out what you mean.

Pastor Paul
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KnightJCK
11-21-2003, 02:33 PM
Hope it works this time. I've edited the above message and uploaded it again. I won't be checking the forum again until Monday. Maybe by then you'll have pictures up for all to see.

Jon
"Don't need a tool twice!"

PastorPaul
11-21-2003, 05:36 PM
Jon,

That's what I'm trying to do. I'll post the measurements this evening, or first thing in the morning, and maybe somebody can give me the angles I need.

Thanks!

Pastor Paul
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"If they don't have woodworking in heaven, I ain't going!!!"

DaveZ
11-21-2003, 06:04 PM
PP, it's all rise over run. The pics above show it pretty good. The run can be obtained by plumbing down from the platform and measuring out to the end of the ramp. The rise is how much height from where the platform to the ramp. If you can get the top angle, the bottom angle is perpendicular to it. Uh, dinner says the wife, I'll try and post a pic later to show how to scribe it as you'd need a weird looking square to step it off anywho. ;)

PastorPaul
11-21-2003, 06:27 PM
I think I understand that whole rise to run thing, but my problem is how to determine where to make that bottom cut.

My father-in-law suggested that I put both pieces of the stringer together (had to go with a 12' and 6' in order to line up with the posts for bolting the stringers on) and then determine my cut. I was thinking that I should cut the porch end of the 12' (actually a 14' to give me cutting length), then cut the other end that will bolt to the post so it is parallel to the first cut. After that I figured to put the porch cut on the 6' stringer (again using an 8' to give cutting length), so it matches up to the 12' where they meet at the post.

After that I get lost as to how I find the spot to make that bottom cut. Here's Jon's picture with my measurements added.

http://webpages.charter.net/chalosi/Ramp.jpg

The top of the 2x6 stringer needs to be 15 1/8" above the sidewalk to allow for the 5/4 deck board to match the porch deck. The run from the porch to the end of the last post is 18' 2". I figure the ramp should run 6" to 12" longer to make sure there is enough lumber left to bolt into the post.

OK, now can someone tell me where to make that cut?


Pastor Paul
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"If they don't have woodworking in heaven, I ain't going!!!"

PastorPaul
11-22-2003, 12:48 AM
OK, Dave! Now I think I've got it.

My concern is the fact that I am working with 2 boards for each stringer. They will be bolted end to end at the posts that are 12' from the porch.

Can I do the following? After I get my line marked where the top of the stringer will go along the posts, can I cut my first board on both ends, so it will be the correct length to meet the second board in the middle of the post (both ends plumb, of course)? Then can I clamp the second board to the first, so the end is where you show in #10, mark my end cut, then cut the upper end plumb to match the first board?

Or am I better off going out and finding 20' 2x6's so it can all be done without worrying about how it lines up with the posts? If I can find them, it would sure make things easier.

There is one problem I see with your illustration. Or at least it appears to be a problem. In #10 and #11, you show the stringer set on top of the platform. Since the top edge of the stringer has to be 1" below the top of the platform to allow for the 5/4 decking boards, will figuring from the top of the platform instead of 1" down from the top make any difference? Or, can I leave the 2x4 decking off the platform, cut a scrap the correct thickness to allow for the difference between the platform decking and the ramp decking, tack that scrap to the top of the frame temporarily and use that as my top of platform point?

Pastor Paul
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PastorPaul
11-22-2003, 10:16 AM
Dave,

I just found a lumber company to the east of us (I usually go west, since it is closer by a couple of miles.), that has 20' 2x6's for less than using two shorter ones. Even with the cost of gas for the drive it is cheaper (They won't deliver just 3 pieces of lumber 13 miles.).

Your new directions have me confused. Wouldn't it be easier to figure if I just used that scrap on the joists to set where the top of the stringer is going to be? That way I have already allowed for the thickness of the ramp decking boards.

Pastor Paul
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"If they don't have woodworking in heaven, I ain't going!!!"

DaveZ
11-22-2003, 11:25 AM
You can do that. Actually I would do it like it's outlined above, forgetting the drop to accomodate the decking for now. Then I would test fit the stringer. At this point it will be too high, which means you have more wood than you need on the stringer, which is good because you might need to "conform" that long bottom cut a little to account for any grade inconsistencies. when you are comfortable with the fit, just cut the drop height off the bottom. So if you need to drop 1", just take 1" off the bottom, parrallel to the cut you have on there. A little wiggle room and a second cut is better than that second trip to the lumber yard ;)

Cody Colston
11-22-2003, 03:08 PM
Well I'll be...

Thanks Dave, I learned something new there. I like those "no math required" methods. :P

Cody


What isn't tried won't work

Breaddrink
11-22-2003, 06:43 PM
Going to post some pics of your new project, paul?

Sounds like it's been at the front of your mind for some time now.

Letting these things go is the problem...Before you know it you'll be adding pit stops at the side and painting flames down the middle of it.

Rob.

PastorPaul
11-22-2003, 06:58 PM
OK. I just assumed that working from the top, instead of from where the stringer will actually be, would throw off the angle of the cut.

Slipped into Cuba (sorry guys, I forgot to stock up on cigars) and grabbed 3 20 footers. I think I'm going to use the full length, allowing for cuts of course, so the ramp extents slightly beyond the last set of posts. It gives me an even better slope (ADA only calls for 15 1/2'), plus there will be more stringer to bolt to the end posts.

Pastor Paul
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"If they don't have woodworking in heaven, I ain't going!!!"

PastorPaul
11-22-2003, 07:39 PM
Rob,

We've already taken some pictures of the concrete work in progress. If the weather permits, I'll get some shots tomorrow of the partial construction of the platform. We'll be shooting the ramp construction, the completed project, and the ribbon cutting with the possibility of some local dignitaries there. After the film is processed and on CD, I'll post the shots.

BTW - Today we had four guys from one of the frats at UMR come over and do the backfilling for us. The guy that seemed to be the leader is a civil engineering student, who does landscaping during the summer, so he knew what he was doing. I still have a little touch up backfilling to do, but they got one heck of a bunch of soil moved for a $20 donation, which they use to support their charitable projects. They spent their whole day doing this kind of stuff to raise money.

Pastor Paul
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"If they don't have woodworking in heaven, I ain't going!!!"

KnightJCK
06-02-2010, 09:18 AM
Paul,
Is this the general idea?

EDIT: Picture below ...

Notice I've shown the framing member a little below the top of the porch to account for your decking material thickness. The cut where the 2 by meets the porch is figured as Cody said. The long cut that rests on the sidewalk is the complementary angle.

Is this what you're trying to accomplish? If so, fill in the measurements and many here can figure the angles for ya'. Also, it would make a difference if the sidewalk itself has any slope.

Jon
"Don't need a tool twice!"

Cody Colston
06-02-2010, 09:18 AM
PP,

No, there is no rise at the bottom. Just mark the stringer along the long side of the square. This will give you a level line when the stringer is in position. And yes, the stringer will just come to a point. See the attached dwg.

Cody


What isn't tried won't work

DaveZ
06-02-2010, 09:18 AM
Piece of cake PP. Hopefully you can follow this(or I can make it clear enough lol) Take your stringer board and set it up as in this pic

DaveZ
06-02-2010, 09:18 AM
It's important to have the board on the end point. Now mark a line(plumb) up from the front edge of the platform. That's your top angle, if you need the actual degrees, find it with a speed square.

DaveZ
06-02-2010, 09:18 AM
Now, take a measure from the starting point at the platform to the end point. Cut the top of the stringer board on the same line/ angle you got in the previous step. You don't have to cut "that actual line" as that might prove to be wasteful, but cut the same angle at the top. Now hook your tape over that edge and measure down the top edge of the stringer and mark the dimension you got from the drawing below. That is where the end cut begins. Now take a scrap that is the same angle as the top cut and lay it on the face of the stringer and use a framing square against that(the bottom cut is 90 degrees from the top cut) and connect to the end point previously measured. That's it.

DaveZ
06-02-2010, 09:18 AM
One more pic. You might need to add a straight edge to the square or use a sheetrock square. No math required :)

DaveZ
06-02-2010, 09:18 AM
Ok, these are good questions, let's see...

You would be better off with one long board, but not absolutely critical. If using two smaller boards you can apply a scab on one side temporarily to make it one board, then proceed as above

In 10 & 11 the board is on top of the platform and on the end point which enables you to use the bottom edge of the board to form a line from which you can obtain your plumb angle

Now take that plumb angle and transfer it onto the edge of a piece of 5/4 decking. Measure that line for length. From the "finished" surface on the platform, that is the length that you would want to drop the stringer(to accomodate matching of the deck boards) So you just take this amount off the bottom cut(parrallel to the cut). This will line up your boards at top, and at the bottom your decking will end on your end point

While my drawings don't show the actual deck board on the platform, it should be there (or a replica) before you start this process.