I need Carpentry advice on stairs

[Tom]

One of my Oldtimers has asked me to help him find out how to make the bullnose first step of stairs.  He is one of the most talented knumbskulls I've ever known, why he's asking me I don't know.  

He's a multiple decorated hero from the Korean war and lived through more pain than most of us will ever see while still fighting for his flag, protecting and driving his men and earning the deserved name "Groundhog".  Semper Fi !

He is an acomplished electrician, diesel mechanic and cattleman who has built his own house, laying all the brick even, and is now building one for his daughter and son-in-law.
He won't back off from anything.(man, could I tell some little stories of him later)

After all the conflagration of building this entire house, he is stumped by one little thing, how to bend the curve and measure the distances of the first bullnose step of the stairs.

This corner of the first step is what he is asking about.

He wants to know how to measure for the bend and how to make the bend.  He saw on TV a fellow bend by making saw kerf and steaming.  He has decided that he will make a steamer of some sort. ("it only takes 30 seconds or so") :D

How deep do you make the saw kerfs?  How wide do they have to be not to close as you bend?

How about some of you carpenter types give me a hand?

I got this picture and some very good information from a link I found on Google but it covers everything except what he wants to know.   STAIR LINK

[Rick Schmalzried]

Tom,
First off, I have never made stair treads, but I have done quite a bit of woodworking.  I am thinking that he is wanting to make a stair tread shaped similar to this (loking from the top):


I am assuming that he doesn't want end grain going around the edge of the stair, and he also isn't content to simply miter 2 boards and then cut the bull nose out, resulting in something like this (The arrows show the grain direction).


(If he does this, make sure to reinforce the joint with biscuits or splines, otherwise seasonal wood movement and continued stepping will cause the joint to open up.)

If neither of these work, he is really looking at a big job as the tread and a banding will have to be made in 2 seperate pieces.  The blank would be cut to exactly the same shape as the step and then the banding would be steamed and attached to the blank.  Finally the banding would be routed to give it the desired edge profile.  If the banding is shaped prior to attaching it to the tread, it is likely that it will deform during the steaming/bending/clamping phase.  If the banding is nailed to the tread in the attachment phase, you won't be able to route a profile due to the nails.  I suppose you could glue and screw the banding then remove the screws after the glue had dried and then route the profile, ending up with something like this.


Personally, I think the mitering would be the best option of these.  I would be concerned with movement of the tread causing the banding to come lose over time.  The option to avoid this is use plywood, but then the veneer is so thin that you will probably scratch through it over time....

If all my assumptions are incorrect and he just wants to make a single board and can't determine how to cut it....Make a template out of cardboard.  Trim it to the exact size of the stairway, then use it to draw the shape on the tread blank.  The offset/overhang can be drawn with a set of calipers, or use a socket the proper diameter as a spacer to draw the line.  Cut and sand to the line and then shape the tread.  The only 2 measurements he will need are the width of the tread (should be the same as all the others) and the length needed.

--Rick

[biziedizie]

Kinda have to be on the job to give exact advice but I can tell you one thing it takes awhile to do what you want.
  As everyone wants everything right now I just cut corners and buy the bullnose from a moulding shop. They have different styles and it all looks pretty good. Home Depot sells the stuff but it's raised and it feels like your walking on rocks!
  To give you an idea as to how long it will take I charge $100.00 per step just for labor and $100.00 per step for mat. so if you take the average staircase with 14 treads that's $2800.00 and that's just for store bought stuff. If I build on site it's triple that. I would say that the average staircase takes about a week to do but if I was you I would buy the bullnoseing from a store and save yourself alot of headaches!

    Steve

[Tom]

Thanks Bizie 'n Rick,
I don't think that suggesting buying from the store is an option.  He's obstinate and determined.

The first step he'll be making isn't just the tread but the riser as well.  I think it is the riser that confounds him the most.  What a lot of the sites also call a "bull block".  He has already made some real pretty molding and window sills from oak, with routed edges etc. The treads will be Red Oak and he will be routing the edges of them as well.  He wants it to be fancy and for his grandkids to be able to say Granddaddy built the whole house.

[biziedizie]

Here's another suggestion, depending on how picky he is about things being exact when it comes to measuring the rise and run do it in cms. The standard way to calculate stairs is 7/11 and doing things in inches is the way most of us do things. I always do my stairs in cms because I will come up with an exact equation and I'm never left with a half inch that I would have to add to the top or the bottom riser.
  I notice at Home Depot they sell pre-cut stringers and I always shake my head when I see those things, like how do they know the height of the second story in ones home?

  Steve

[Minnesota_boy]

Steve,
That's an easy one.  You buy the stair stringers first, then build the rest of the house to fit. :D

[Tom]

The stringers are in place and have been used to reach the second floor during the construction of the house.  there are four of them cut from full measure 2x12's.  The temporary treads are full measure 2X's as well. He will be replacing them with 4/4 red oak treads.

[beenthere]

Tom. Maybe go to the Shoot-out and get a few "sheets" of that thin material, and build up a wrap-around piece on a form that will fit the shape wanted for the bottom riser, or "bull block".   As thin as they are being reported, a dozen sheets should give about the right thickness for a riser.  Just a thought.

I gather that the riser is the main interest in your quest to help here.

[Scott_R]

To make a kerf back bend he should make his cuts to within 1/16"-3/32" of the face of the riser. The cuts should have 3/8" between them if he is using a standard thickness carbide blade. Making a trial stick mockup is a good idea. This mockup can be used to check the fit of outside cauls that should be used while the epoxy sets. An easier option to the steambox is an ordinary steam iron. Holding the riser in hand #1 while hand #2 runs the iron, hands #3 and #4 are mixing epoxy. Pour epoxy in the kerfs and clamp using hands #5 and #6. Hands #3 and #4 may not be used for this purpose as they will be busy wiping epoxy from wifes iron. Allow to set and trim as needed. The other method used is to have his supplier order it from Brosco Best of luck, Scott

[ADfields]

Tom, is it the tread or that bent riser that has him stumped?   I'm guessing the riser and he wants to bend it and not cut and return it twice and round the corners.   Rule of thumb I was shown on kerf cuts "back cuts" is 2/3 the thickness and remove 50% so with a 1/16" cut you would leave 1/16 of wood to the next cut.   Needs to be balanced and true cuts to same depth and space all the way not just eyeballed up cuts.   I would boil it in a 55 gallon drum to make the bends rather then steam, it's slower but more even.   Water or steam will swell the wood so he needs to allow extra for when it drys.   I have made a lot of bends but not this tight and I bet he kills 2 or 3 before he gets a piece of wood that will do it and not fray out splinters on him.   He will need a form to bend it around and clamp to.   It's all in just the right hunk of wood hear so set out with several and don't get mad when most don't work. ;)   Could also lam up thin 1/8" thick dampened boards inside a form made from bendable plywood and get it that way.
Andy

[Minnesota_boy]

I think I'd start with an 8x8 and just round the corner.  Bending wood that far must be a tough proposition.  I think the end grain would look pretty cool too.

[woodmills1]

My barrel making customer will only bend true quartesawn wood.  he says that anything else will delaminate at the rings.  makes sense to me.

[Rick Schmalzried]

If it is the riser that he wants there are quite a few options.  Kerfing the board will work, but can cause sort of a washboard appearance.  What I would suggest is make a template of the riser as it exists now, then make up a form for the inside radius of the rounded end.  Finally use a glued up lamination to bend around the form.  He needs the ability to cut some veneer sheets about 1/8 to 3/16" thick, spread a good amount of glue (really is best with a glue that won't creep, such as an epoxy or resicorcal or however that is spelled) between the layers and then wrap the layers around the form.  Once glued up, use a jointer (or handplane) to true op one edge and then cut the other end parallel with the 1st (I would use a jigsaw or a cordless circular saw).  Finally trim the ends and install.

A glued up lamination method has much less springback than steam bending.  He could also get some bending plywood and wrap a veneer around it.

If he is fixed on a kerfing solution, just wrap a tape around to get a full length, add several inches.  Then start cutting kerfs where the bend starts.  If he wants to get technical about how close to space them, you would use the difference in circumferences between the inside and outside of the board and the kerf width of his sawblade and figure how often to add a kerf.

--Rick