how do you find the centres for bars in railings

[s410man]

just had a job come in making railings

i seem to recall something about adding the diameter of the bar to the overall lenght to find the centres for the bars but cant really remember

any other methods for finding bar centres

thanks

 

[GeorgiePorgie]

This topic has been discussed before,but here's my way taken from the thread it was discussed....

Take a piece of paper/tape,wrap it round the tube,mark a line on the paper where both edges meet,cut paper at this point.

Measure the paper for a accurate centerline.

Mark a point on the tube anywhere with a pencil or center punch,with one edge of the paper lined with the center punch marking and wrap the paper round the tube,the centerline on the paper is half the tubes circumference so mark it on the other side of the tube where it is.

 

[GeorgiePorgie]

Don't suppose you have acess to a Lathe do you? you can get the center spot on using the tailstock center drill.

 

[Sanny]

ok take the inside size of your rail where the bars are going to go and add the thickness of 1 bar then divide it to make your centres, when you are going to mark out your centres take off half the bar thickness on the first size then all the rest will have the same inside size. hth Sandy

 

[Drains]

Don't suppose you have acess to a Lathe do you? you can get the center spot on using the tailstock center drill.

I think you need to read the original question again Georgie .

 

[wyn]

I used the same method as Sanny yesterday marking out for bars in a gate.
The first centre point for the first bar is the gap you want plus half the diameter of the bar. The rest are the gap plus the diameter of the bar.
The other end bar is similar to the first.

I made the mistake of marking out the centres by measuring from the previous to the next...this ended up with the last marks being out....All the errors were compounded

 

[Delgado]

I'm sure there's many ways to do it, but I normally....

Work out how many gaps I need to get me as close as I can to the centres that I want, by dividing up the overal length.

Then, If, for example I've got 18 gaps then I know that I need 17 bars so I'd multiply the diameter of the bars by 17.

Then, I'd take that figure away from the overal length and divide the result by 18 (the number of gaps) to give me the length of each space between the bars.

For example;

Say You've got a 2000mm length of railing

You want 18 gaps.

You've got 17 bars of 20mm diameter (17x20=340)

Take 340 from overall length (2000-340=1660)

Divide 1660 by number of gaps (1660 Divided by 18 = 92.2)

Gap between each bar will be 92.2mm (If I don't like that gap, then I'd work it out again with less or more bars).

The reason that I'd do it this way, is because I wouldn't bother marking the whole thing out with the actual centres, I'd just cut spacers to the length of the gap, get the end ones tacked in, square it up, tack the middle one in, then work outwards from the centre using the spacers.

A couple of photos of some gates I made using the above method of spacing the bars ...

 

[Delgado]

I made the mistake of marking out the centres by measuring from the previous to the next...this ended up with the last marks being out....All the errors were compounded

Never made that mistake before, honest!

 

[pedrobedro]

Just make them close enough for a small child not to get their head stuck. No-one is going to mind a different gap at one end in the great scheme of things.

 

[mike os]

max gap for building reg compliance is 100mm (actually a 100mm sphere cannot pass through)

 

[GeorgiePorgie]

I think you need to read the original question again Georgie .

 

[breezer]

Or go for chaos theory random...

 

[inchpincher]

When I built a gate for our workshop I just bought a length of predrilled bar from the local stockholder, almost looked professional when finished!

 

[Tigman]

You can get holed bar , makes everything easy !

 

[s410man]

Just make them close enough for a small child not to get their head stuck. No-one is going to mind a different gap at one end in the great scheme of things.

anyone got a small child i can borrow?

try telling that to my boss

now done anyway

i added 12mm to the bar lenght the divided by 110 which should give me gaps of 98mm

whatever it came out as i rounded up to the next whole number

this was how many bars i needed

i then started with my original number plus 12 and divided by the number of bars

thanks for all the help