Stair Design Sofware

[GlenP]

Hi Everyone. I am looking for software to help with cutting and designing stairs. I have done lots of sets by hand but now that I have the bot I am considering using the machine to router out the stingers. Also any tips on repositioning stringer when they exceed table length.
Thanks in advance,
Glen

[Gary Campbell]

Glen...
Christian Magro is going to do a Wiki article on his methods of designing some very nice stairs. It was discussed in this post:http://www.talkshopbot.com/forum/messages/17997/26830.html?1200783216

For straight stringers, I built an Excel spreadsheet that does all my rise/run, tread and riser thickness and floor finish offsets and then outputs plot points that I manually enter into VCPro. I imagine that "the scary smart programmer types" can do this with a mouse click.

If you need to cut longer than the Bot table, all you need to do is place an indexing circle at each corner of the rise/run vectors and then drill each one 0.10 deep on the section you are milling. When that section is complete, you can then move the machine to the known coordinates and index the material to the bit. Hope this helps.
Gary

[renklint]

I'm so glad you asked Glen, I'm also wondering how to reposition boards or sheets on the shopbot. Since I don't have a shopbot yet and having english as my second language, I have some difficulties understanding your answer Gary. These are images of how I understand your answer (I don't do stairs either, so not shure exactly what a stringer looks like...)

8094
Drill in the area you want to cut. After the first cut, reposition, jog to the drilled hole and rezero. Or... am I missing something?

8095

/Lars

[henrik_o]

I'm not entirely sure I understand Gary's re-positioning technique either.

I've done one and only one x axis re-positioning job, I used fixed stops along the x to keep the workpiece aligned and zeroed the program to a mark in one of the stops. By marking the workpiece for each iteration I wanted to machine, I could line up the marking on the workpiece with the marking on the stop: as long as a +/-0.5mm tolerance is ok that seemed to work very well.

[Gary Campbell]

Lars, Henrik..
It seems that I did not do a very good job of explaining my version of indexing marks. I will try to explain 2 methods that I use.

1) As it pertains to closed face stair stringers, Lars your drawing is accurate, and I would put some kind of marker (indexing hole) on every tread or inside the triangle shown on your drawing. Make sure that the distance between the holes is exactly the hypotenuse of the simple rise/run combination of the stringer. (Have the amount you plan on moving the stringer be a mulitiple of this number) The reason that I use holes (even tho very shallow) is that you can always click on an individual hole (circle) and and get its exact center X & Y coordinates. Most of the cutouts we have done lately have been open type like this post:http://www.talkshopbot.com/forum/messages/17997/26830.html?1200783216

I would draw the complete stringer on an oversize model and then break it into 2 overlapping cut sets. Since we are cutting the complete outside profile, we must use an indexing method that is not on the exterior edge. You may have to use a 1/2 bit dia. offset and machine along vector, as you will need to cut open vectors to insure you dont cut off the material.

2) The second method is similar to Henrik's post above. Using a straight piece of material that does not have to be profiled, is easier to index along the X. I place some signfoam plastic blocks that overlap the Y zero, held in with nylon socket head cap screws in the T track (you could nail or screw a wood block) and then using the bit I am going to cut the file with cut the exact zero line down the length of the X.(offset 1/2 bit dia.) This leaves an exact zero cut on the face of the blocks. You can then use the blocks to keep the long dimension at Y=0. You will still need to have a method to reindex the X. Hope this helps.
Gary

[renklint]

Thanks Gary,
I'm sure it was perfectly understandable the first time, but my understanding of english isn't all that good. Thanks again for clarifying.
Lars