When Im spacing out my bars for a metal picket gate or fence,Im always come out short at the ends..spacing bars center to center ...whats your foumula for length bar spacing ?
When Im spacing out my bars for a metal picket gate or fence,Im always come out short at the ends..spacing bars center to center ...whats your foumula for length bar spacing ?
Figure out what spacing you want, say 4", divide that into the space that you have to get the amount of pickets. Obviously you can't have less than a full picket so up it to the nearest number. Take the amout of pickets and multiply it by the thickness of each picket. Subtract this amount from the space you have, this is the amount of gap between each picket....Mike
Ok ..I have a span of 96" .. using 1/2" sq.bars..4" c-c spacing ...96/4=24 bars..then what?
I also run into this problem, and would love to know a good formular for calculating this.
I am not understanding that formula either. If you have 96 inches and want even spacing at 4" that should be 24 pickets. If each picket is 1/2 " thick. If I use mrmikey's formula I would go with 24 times 1/2 = 12 subtract that from the space (96") that gives 84" for the pace between pickets. We know this is not right, so I am missing a step in the process somewhere.
Mrmikey, can you clarify?
If there are 24 pickets, then there are 25 spaces. 4 inches of space between 1/2 thick pickets will net a space of 3 1/2" between. 25x3.5=87.5 add to that the 6 inches of space that the picktets take up gives 93.5 inches. Still 2.5 inches short. that is an additional 1/10th of an inch to add to each space. I am confused.
Ok, you've got
1) 24 bars X .5" = 12"
2) subtract 12" from 96" = 84" that is the amount of space you have to work with
since there's always one more space than bars, you have 24 bars that means 25 spaces
3) 84"/25 =3.36" gap between each picket
since that's hard to read on a tape, 3 23/64" change it to 3 3/8" which is 1/64 more for each gap. (Any difference that there is should be on each end of the railing to make it equal on each end.) So you have 23 gaps not counting each end. Make each of those 3 3/8" which would total 77 5/8". which leaves 6 3/8" that you divide in two, one gap for each end.
4) the first gap would be 3 3/16, the next and each subsequent gap would be 3 3/8"
5) if you have a construction calculator it's easier but you don't need one
6)leaving your tape on the end mark out 3 3/16", 7 1/16", 10 15/16, 14 13/16, 18 11/16.....making sure to put the picket on the same side of the mark.
I realize it sounds complicated but once you do it a couple of times it's not too bad, really.....Mike
Gotcha,
Thanks Mrmikey. Makes sense now.
Thanks for the quick reply, too.
You're welcome, hope it helps....Mike
Must be math here is a little different. If you have 25 spaces at 4", that comes out to 100". What you have is 24 spaces @ 4", which gives you 23 pickets with a 2" c-c gap at each end. A 4" space minus a 1/2" picket always equals 3 1/2", your space between pickets, not 3 3/8 or 3 1/16". Maybe you want to re-check your math?Ok, you've got
1) 24 bars X .5" = 12"
2) subtract 12" from 96" = 84" that is the amount of space you have to work with
since there's always one more space than bars, you have 24 bars that means 25 spaces
3) 84"/25 =3.36" gap between each picket
since that's hard to read on a tape, 3 23/64" change it to 3 3/8" which is 1/64 more for each gap. (Any difference that there is should be on each end of the railing to make it equal on each end.) So you have 23 gaps not counting each end. Make each of those 3 3/8" which would total 77 5/8". which leaves 6 3/8" that you divide in two, one gap for each end.
4) the first gap would be 3 3/16, the next and each subsequent gap would be 3 3/8"
5) if you have a construction calculator it's easier but you don't need one
6)leaving your tape on the end mark out 3 3/16", 7 1/16", 10 15/16, 14 13/16, 18 11/16.....making sure to put the picket on the same side of the mark.
I realize it sounds complicated but once you do it a couple of times it's not too bad, really.....Mike
Ok ..I have a span of 96" .. using 1/2" sq.bars..4" c-c spacing ...96/4=24 bars..then what?
Where did you get the 4" dimension from?
What I had said was:
If the 3.36 gap between ech picket was too tight you could delete a picket or two and work it out from there. The 4" is just a place to start. I took the liberty of narrowing the gap, it could be whatever you want, the math remains the same. I chose to keep the amount of pickets at 24.3) 84"/25 =3.36" gap between each picket
Can't be, if you've got 2"c/c (actually it would be inside to center, I'm assuming that's what you meant) then you have a 1 3/4" gap or space.....Mikea 2" c-c gap at each end.
I was answering the question by the original poster, the one in quotes at the bottom of my reply. The guy looking for the answer. He had a 96" space and wanted 4" c-c spacing, that was taken right from his posting. And the space at each end would be 2", 1 3/4" with the picket installed.Where did you get the 4" dimension from?
What I had said was:
If the 3.36 gap between ech picket was too tight you could delete a picket or two and work it out from there. The 4" is just a place to start. I took the liberty of narrowing the gap, it could be whatever you want, the math remains the same. I chose to keep the amount of pickets at 24.
Can't be, if you've got 2"c/c (actually it would be inside to center, I'm assuming that's what you meant) then you have a 1 3/4" gap or space.....Mike
if you're only trying to meet code and spacing isn't critical to a 16th, and time is crucial, (you'd be amazed how much variation you can get away with in a long run of rails, and it still look good). Lay out the frame of your rail, don't tack yet, just clamp it. Measure the inside to inside dimension, then add 1/2 the thickness of a picket to each end, draw a 2 lines parallel to the pickets about 2 feet long there. now take the top and bottom rails and line them up next to each other along the work fence. clamp at the very ends out of the way. keep them aligned with your 2 lines. Now take your tape and measure from line to line, then hold the dumb end in place and pivot the tape away from the work fence till the line you drew lands on any multiple of whatever your c to c dimension is. (normally 4" o.c. so 4, 8, and 12) when the tape is lined up so your reading from the same side as the corner that touches on the line at the other end, secure the tape in that position. (I like magnets for this) now take your framing square, using the work fence as a guide, and mark the top and bottom rails together at every multiple of your c to c dimension. then put the rail back together tack it, add pickets at marks and go to it. if your doing big runs and have everything pre-cut one person can knock out 100 feet a day, if you have a helper to get it out of your way and clean it for you. This method works on slopes too, but you need a long bevel guage instead of a square.
Build the fence with with a standard spacing and trim the ends where needed, then add post.
Not always an option tho if you have a finite space to work with such as a space between two columns, stair rail etc....MikeBuild the fence with with a standard spacing and trim the ends where needed, then add post.
That is debateble, Mrmikey.
However, what if the finite spacing changes between columns on the same run. Do you recalculate for each section.
Build the rail, then trim, is the way I do it 99% of the time. With a gate I would do custom spacing. Between columns probably not since there is no guarantee spacing will absolutely the same for multiple columns.
Just an option and timesaver, if you are not required do custom spacing.
If you want equal spaces you'd pretty much have to.Do you recalculate for each section.
I agree 100%. If I were doing a run of railing where I could place the posts where I wanted to I'd definetly make up all the sections before hand and place the posts where the end of each section is, by far a much faster way. When you'v got to work with 1/16" to get equal spacing it opens up the possability of numerous mistakes, hell, I can barely see the 1/2" marks on a tape :-).....MikeJust an option and timesaver, if you are not required do custom spacing.
I like my bars to be right next door to each other so the bartenders don't have enough time to call each other and warn them.
Thousands of places for comedians to work...and we stuck with one here LOL ....Mike
In almost every job I do, I can use my 4-1/2" spacing (on a 1/2" picket for 4" in-between).
I shoot for a picket in the middle and then 4-1/2" left and right. If the ones on the ends are just too close as to be an eyesore (which is rare but can happen) then I recalculate for a space in the center and two pickets either side of that 4" space.
Obviously you can't always do that either, especially when sections next too each other have to match, or you have a peaked top rail, but it gives you another option to consider.
Every job is different which is why I like this kind of work.
I've also used a "spreader" as we called it. We put two of them together to span the average bay ( less than 4 ft). It worked well if we was in uh rush, would vary maybe !/8". ........... Can't remember where we gotem'.......If I'm buildin' a "straight" rail usin' 1/2" pickets, lets say the "bay" is 3'-7" inside measurement, add 1/2", 3'-71/2" ok , I start dividin' usually with a guess,,,, Now at 10 spaces the equal space will be 4 3/8"........ this will also work on "rake" rails except that ever thing grows on the diag. YOU can also confort too decimals..........
Don't let that iron in your lungs, turn to lead in your @$$!!!!
A few things I forgot to mention. when you start the 4 3/8" layout you got to start a 1/4" in on the post (this would represent center of the picket), When you lay these out it's easy too end-up long or short on the last one (1/32" off on each one, in 10 spaces =5/16" off on the last one), and these are center measurements for the pickets...........I've worked in some shops that build panels on a standard spacin' of 4/7/16" and then trim each end to center up in the bay...Ya this works, the only thing I don't like about this method is that then another fello "rail" guy looks at them (as I do ) He'll see that!.......And yes it does stand out........Stand back and look at a rail with equal picket spacin' & then one that doesn't. The average "joe" wouldn't notice, but they're not the ones that build em'. It does take alittle longer but I think it's worth the time. I don't want someone to say " man, that rail looks like $!@#! "........ Attention too detail goes a long-way, I take PRIDE in buildin' all my projects too the best of my ability, as I'm sure most of you do!......MY 2 3/32 cents!!!!!!!!!!!!!!!!!
Don't let that iron in your lungs, turn to lead in your @$$!!!!
This shows two pretty cool ways.
http://www.Rockwelder.com/Flash/spacing/spacing.html
This is another, that I use in the macro in that movie.
You take the space you want between bars. Lets say it is 3.5 inches, a common space today.
You subtract that from the length. Then you add that space and the width of one bar together. Divide that into what is left of your total space.
That is how many bars you need. Plus or minus a fractional bar.
Then as others mentioned you, take the number of bars times their width, And subtract that from the total length. What you have left you divide by the number of bars plus one. That is the width of each space.
If I am using a calculator at this point I take the space measurement. Usually around 3.584 or something. I add that to one bar width. That is my first mark. It marks the right side of the bar. If you are starting on the left. It is not a center mark rather a right side mark.
Now I take the space and the width of one bar, and store them in the calculator memory. From then on I just hit the addition key, the memory recall key, and the equal or answer key. And I get each new increment, that marks the right side of the bar. I just right them down in decimal and convert them as I go.
Sincerely,
William McCormick
I don't know if you saw the movie or not. But you can, for a half inch square bar, upright, hang the tape measure over the edge of the table at the start by 1/4" and at the end let the tape measure overhang by one quarter. Meaning instead of lining it up on 72 just line it up on 71 and three quarters. This will help correct the quarter inch difference you get because of the half inch square bar.
If you had one inch square bars, You would be off by one half inch. So in that case you would almost have to hang the tape measure over a half inch to correct it.
For larger bars you can use five inch increments.
Sincerely,
William McCormick
Last edited by William McCormick Jr; 04-28-2009 at 07:27 PM.
Try this in an excel sheet
Column A .................................Column B
Day Light..................................Enter your size
Hinge allowance........................Enter your size
Latch Allowance........................Enter your size
Stile Width................................Enter your size
Max Gap...................................Enter your size
Baluster Width...........................Enter your size
No. Balusters............................=B8-1
No of Gaps................................ =INT(((B10+B6)/(B5+B6))+1)
Gap Size.................................. =((B10-(B7*B6))/B8)
Transom Length.........................=B1-B2-B3-(B4*2)
Exactly right and can be used for all openings, balusters , stiles , hinges and locks
Brett
Last edited by Brett; 04-29-2009 at 03:34 AM.
A good guess is better than a bad measurement