Cable tray rolling bend!

[Calash1]

Hello guys/gals,

Fabricating your own bends is normally now a dated thing in this day and age but still wise to know! I like to think I am pretty good at this but one thing I did stumble on today is doing a back to back rolling bend in cable tray?!! Making the bends is a doddle but does anyone know how to get a back to back in one length?!! Formula for it?

Thanks in advance

 

[Midwest]

If I knew what a back to back bend was, I might be able to help. That said, it was thirty years ago that I did any cable tray, so whom I'm I to say.

 

[telectrix]

me confudes dot com also, does yous mean a internal 90 folldew witha nn external 90?

 

[Rpa07]

Or a loop de loop?
The learning lounge has a few ‘masterclasses’ in traditional tray Work.

 

[Calash1]

!! Like a conduit back to back bend. As in two 90s in the same piece with no joints! Either internal or external as the principle still the same! Head scratcher!

 

[Leesparkykent]

!! Like a conduit back to back bend. As in two 90s in the same piece with no joints! Either internal or external as the principle still the same! Head scratcher!

Make one 90 degree bend then make another

 

[freddo]

Doing it the other day, I just made one bend then marked and made the other. Much faster with conduit. I like installing the light gauge stuff as I own a Hilmor cable tray bender.

 

[ipf]

Just make a couple of 90 degree bends.
Never heard of a formula for bends? You could try asking Lewis Hamilton.

 

[PEG]

I do have an old engineer's bible,which describes the calculations for such work,but it is very specific,to individual types and grades of section and material.
The material has to be manufactured to very high tolerances,to remain consistent...as anyone who has done 90's in scaffold tubing,with a roller/sector bender,can testify...with every forth bend,folding

It is usually easier to estimate,and gauge any alterations,on the basis of results.

With any bending done,on metal sections,it is always worth remembering,it prefers to stretch,than to compress,and compression can mean rippling.

Working with lead,dressing and forming,can give you a great,exaggerated demonstration of the properties of a metal,and assist in guessing what happens,when working less ductile materials.

 

[Jim90]

Had to put 29 lengths in the other day.
Just use a tape measure man and mark out everything equally. Draw it out if you have to.
Just promise me you’ll use a file!