I discovered yesterday the biggest mistake by far I have ever made in my stairshop. I have two 180 degree stairways going and a third one about to start. I posted a picture here and the stairway I goofed up on is the one on the right.
Heres the goof up. This stairway fits into a poured concrete turret. I went to extreme pains to collect data on this stairway as far as variances from a true cylindrical form. What I did was stretch a string on the axis of this turret. It went to the ceiling down to the floor with a plumb bob laying it out. The cylinder measures 186.5 inches across….so this would be a 93.25 inch radius….simple..I have done this carefully hundreds of times.
I plotted each treads position on the turret walls…then measured to the stretched vertical string to plot the variances. I had over a 1.25 inch change from the true 93.25 inch radius. No problem….I just built the forms with these built in errors all around the half circle.
My error was I misread my tape and originally drew out an 83.25 inch radius circle instead of 93.25 inches! What distracted me was I made a new layout sheet with all the deviations marked on it for all 18 treads….in other words…how much the stringer was in or out from the true 93.25 inch circle. I was so busy micro managing these deviations….and so proud of how clever my system was….that I failed to notice I was adding and subtracting all these deviations from 83.25 inches instead of 93.25 inches….a whole 10 inches of radius difference!
I always cross check to catch an error like this…but my cross checking didnt occur until after I had laminated up both stringers. I was laying out the outside stringer runs….and measured them….then went to my calculator to non chalantly see that they were the same as computed. My numbers werent adding up…and then I thought impossible. I even rechecked the radius measurement…and I still had a mental glitch thinking that 83.25 inches was the correct radius….until I noticed that the diameter should be 186.5 inches. I just divided that by two and uh oh,…..93.25 inches!!! I just sat down, and shook my head,,,,,then analyzed the fix. I was proud I didnt throw a tantrum…but actually was thankful I had not routed the stringer yet. It could be saved….except I would have to splice on to it. I rolled up my sleeves and immeditely tore out the outside wall forms…..and rebuilt to the correct radius….along with all the astigmatism adjustments for the uneven curvature. I then placed the smaller radius stringer into position on the larger radius forms. Next I had to surgically go into each laminate splitting them along the glue lines….and staggering each layer so I would have a strong splice. This worked out fine…and now 2 days later I am back on track.
I make lots of small mistakes…but have never made any error this big before.
Oh well…..they always say a good finish carpenter isnt judged by his work done correctly…but how he can handle his mistakes.
I always post what happens…..and this is no exception. I could have kept it quiet of course…but I feel better telling more than just the successes in my business.
Anyway…I am on track again….relieved that I didnt go ahead and assemble this whole stairway….and then discover the error when it had a ten inch gap all the way around it in the turret.
I have never had to trim my outside stringers,,,ever,,,,but this time I would have had to put two step curved crown moulding!
Geesshhhhhh ……
Stan
Edited 2/20/2009 11:46 pm ET by StanFoster
Edited 2/20/2009 11:52 pm ET by StanFoster
Replies
Ah, well. Seems yer only a demi-god.
;-)
Forrest
Sheesssh happens
finest kind....
<<<they always say a good finish carpenter isnt judged by his work done correctly...but how he can handle his mistakes>>>
i wish i had a nickle for everytime Roy has quoted that to me
yeah ... somehow the boss never seems to appreciate the wisdom of the ages ...
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
ya coulda just caulked it in after install...probably would've had to use a backer rod though..
:-)
Mike
ya coulda just caulked it in after install...probably would've had to use a backer rod though..
I think drain pipe would work as backer rod.
Rich
if i had to post my screw ups each day... we'd need a new forum... so many so often... it's now considered the norm....
lame attempt at try'n to look human... but thanks for the effort
:)p
I don't know how many times I run out my tape, ( and in a hurry) think it's hooked and read number, cut,. Only to fine I am 1 inch short!!!!!!!. I got tape hooked on one of the rivets of the hook instead of end AAAAAGGGGH!
Some brand tapes are more prone to this than others. Usually ruff framing and cost of mistake is not alot time or $. P.S. : I am a Journeyman carpenter w/ over 25 yrs. of learning experience !!!! lol
Edited 2/21/2009 8:49 am ET by artworks
"I don't know how many times I run out my tape, ( and in a hurry) think it's hooked and read number, cut,. Only to fine I am 1 inch short!!!!!!!"Gee....I've, uh, never done that.
Stan, a popular saying I've heard for years is "The only guy who hasn't made a mistake is the one that hasn't done any work." buic
Daytona!
I've come to a place lately myself, that I found I can take as much pride in how I fix my mistakes as I can in building the project itself. Even if ya just have to start over, it usually goes a lot quicker the second time. ;-)
Ott
http://www.ottcarpentry.com
as i get older i find i walk 2 miles sideways for every mile i walk foreward it seems
sometimes the merte fact we survive in business seems like a monumental accomplishment !
" If you cant dazzle them with brilliance , baffle them with bullsh*t " ( copied from a succesful farmers barn door along the way " )
I was punished by this mistake by causing my occupation to turn into plain ol work as I fixed my error Friday and Saturday. I never mess with my stairways on Saturdays...but yesterday I did. I am all caught up now...ready to resume my love for going to the shop Monday morning. I am still perplexed how after all the hundreds of curved stairways I have layed out...double and triple checked...and installed...that this one had this huge error so far into the build stage.
What really scares me is that I could have easily went ahead and routed the stringer...and then installed all the treads and risers and it would have been a total scrap pile.
Stan
Edited 2/22/2009 8:29 am ET by StanFoster
Ya want I should come up and go over all whirly-gig parts you installed? (G)
Now THAT would be a BIG mistake, stairs too small? Not too big.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
scrap pile.... nope... it then becomes a "display"
:)
p
We all make mistakes, try as we might to avoid them.
Thankfully most mistakes are fixable. I sometimes think of the scene in Apollo 13 when Tom Hanks asks his crew mate, "What's that about?" pointing to a note taped over a switch that says "NO!" in bold black ink.
The answer was, "Oh that... I was getting punchy and didn't want to cut the Lunar Module loose with you guys in it."
I made a minor mistake this week, while routing flutes for some columns. I left my flute limit stop off and over ran a flute... funny thing was it looked like it was giving me the finger. <g>
Inspired by the Apollo 13 scene (though hardly that important), I made myself a note on the cleat where the stop needs to be before I fire up the router.
Edited 2/22/2009 10:45 am ET by basswood
That's funny. Here's one example of how I attempt to save myself from myself. It's particularly easy to make a mistake when performing a repeated action. In this case, I needed to make several hundred holes.
View Image
Good going there. We could write a book, "Carpentry for Dummies" based on how we try to idiot-proof our work.Unfortunately, some people cannot be saved from themselves (thinking of two construction workers who made the 2001 Darwin Awards; they fell to their deaths after cutting a circular hole in the floor, while they were standing in the circle.)
I usually 'waste' the time and tape to cover the holes I don't want to use.
I would have gone back over the other column faces and made them match. Sold it as being a custom job and unique! Had an old boss always yacking about lemons into lemonade.
They can't get your Goat if you don't tell them where it is hidden.
If you like that pattern, you may want to use this gable vent arrangement (not directed at you) ;o)
<G> Yea that would work some days.
They can't get your Goat if you don't tell them where it is hidden.
That might fit on the "Job Site View" project
are you mad at anyone in Carlton?
;-)
Not really , and the truth is I have escaped detection by some of the "powers that be" on this site so far and would prefer to keep it that way.
The building is visible for a lot further away and from more places than I had imagined! Funny how if I can see someplace from the site they can see my site. Maybe save it for the last day on the job.;-)
They can't get your Goat if you don't tell them where it is hidden.
I am chomping at the bit to get to the stairshop in the morning and "continue" on with it. I bit the bullet.....dealt with mistake...and now its full speed ahead.....<G>
Stan
Inchitis will never be cured, and ten-inchitis is a mere mutation of the original virus. I would have had a coniption anyway.
truehaven= When I make a mistake...I make a mistake! 10 inches...wow.....
Stan
Edited 2/22/2009 7:53 pm ET by StanFoster