[Richard]

I'm (fairly) good at sticking bits of trailer together with my MIG but
have never built anything from scratch.

Friend wants me to build him a light duty security door which will allow
him to prop the main door to an underground building open so as to allow
increased air flow but which exclude unwanted visitors. I guess that he
envisages something like a tennis court gate but with expanded sheet
steel in place of the chain link netting.

So, to the questions. Assuming that I make the frame and door from RSA
steel, how do ensure that everything stays flat and square as I weld it
up? Do I need more/fewer/different braces? How do I attach hinges and
locks? Any pointers to plans/instuctions on the web would be much
appreciated.

TIA

Richard

[Clint Sharp]

In message , Richard
writes
I'm (fairly) good at sticking bits of trailer together with my MIG but
have never built anything from scratch.
It's easier IMHO, you get nice clean corrosion free metal of your
choosing and you can set up the MIG on the offcuts so you know exactly
how it's going to work.

So, to the questions. Assuming that I make the frame and door from
RSA steel, how do ensure that everything stays flat and square as I
weld it up? Do I need more/fewer/different braces? How do I attach
hinges and locks? Any pointers to plans/instuctions on the web would
be much appreciated.
I'm probably completely wrong and going to be shot down in flames but
when I've built frames in the past I've used magnetic squares on corners
and put a tack weld on each corner/joint. Once the frame was 'complete'
I checked for square , adjusted as necessary and then finished off each
joint. Obviously measuring and cutting accurately makes your life *much*
easier in that respect.

I made my own hinges with tube and bar but my application probably
wasn't the same as yours and I didn't need a lock. ISTR that Machine
Mart had a range of metals and bits like hinges etc. for building gates?
Might be worth a look.

TIA

Richard

--
Clint Sharp

[Harry Bloomfield[_3_]]

Richard submitted this idea :
I'm (fairly) good at sticking bits of trailer together with my MIG but have
never built anything from scratch.

Friend wants me to build him a light duty security door which will allow him
to prop the main door to an underground building open so as to allow
increased air flow but which exclude unwanted visitors. I guess that he
envisages something like a tennis court gate but with expanded sheet steel in
place of the chain link netting.

So, to the questions. Assuming that I make the frame and door from RSA
steel, how do ensure that everything stays flat and square as I weld it up?
Do I need more/fewer/different braces? How do I attach hinges and locks?
Any pointers to plans/instuctions on the web would be much appreciated.

Depending upon the accuracy needed, it needs to be laid out on a good
flat surface and either clamped or weighted down so it doesn't move.
Then make several tack welds around the various bits, before
progressing on to the full weld runs.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

[Tim Lamb[_2_]]

In message , Harry
Bloomfield writes
Richard submitted this idea :
I'm (fairly) good at sticking bits of trailer together with my MIG
but have never built anything from scratch.

Friend wants me to build him a light duty security door which will
allow him to prop the main door to an underground building open so as
to allow increased air flow but which exclude unwanted visitors. I
guess that he envisages something like a tennis court gate but with
expanded sheet steel in place of the chain link netting.

So, to the questions. Assuming that I make the frame and door from
RSA steel, how do ensure that everything stays flat and square as I
weld it up? Do I need more/fewer/different braces? How do I attach
hinges and locks? Any pointers to plans/instuctions on the web would
be much appreciated.

Depending upon the accuracy needed, it needs to be laid out on a good
flat surface and either clamped or weighted down so it doesn't move.
Then make several tack welds around the various bits, before
progressing on to the full weld runs.

For largish agricultural doors (2mx5m) I use 50mm x 50mm box section.
For a similar weight, you get much more stiffness.

As others have said, tacking is essential to avoid movement as welds
cool and to allow adjustment on checking for square. I am fortunate in
having large areas of concrete floor to work on. Using stick welding, I
find vertical runs difficult so keep turning the work to provide
horizontal welds.

While we are here, has anyone a sub 99ukp auto darkening welding shield
to recommend?

regards




--
Tim Lamb

[Richard]

Harry Bloomfield wrote:


Depending upon the accuracy needed, it needs to be laid out on a good
flat surface and either clamped or weighted down so it doesn't move.
Then make several tack welds around the various bits, before progressing
on to the full weld runs.



I had wondered about making accurate 90 deg corner plates at home and
taking those to site to use almost jig-like to ensure accuracy. Might
that work?

Richard

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Richard saying
something like:

I had wondered about making accurate 90 deg corner plates at home and
taking those to site to use almost jig-like to ensure accuracy. Might
that work?

Of course.
--

Dave

[Andy Dingley]

On 24 Feb, 20:07, Richard wrote:

how do ensure that everything stays flat and square as I weld it

Tack it together carelesssly with _small_ tacks, then bend it very
carefully to be as absolutely flat as you can make it.

A concrete driveway is _not_ a trustworthy surface plate, unless
you've verified it to be flat first. However the water surface on a
flooded driveway is! Probably the simplest method for a single edge
is to use a long aluminium brickie's spirit level.

Once you then have it wedged carefully to be level, and weighted down
so that it won't warp (much) you can then proceed to do the finish
welds. Do these slowly, allowing heat to dissipate between them.

if you have to, weld temporary stays in place and angle-grinder them
off afterwards. Don't trust a mag clamp to hold anything accurately in
place. Don't trust a cheap mag clamp (or cheap non-Vise Grip vise
grips) to even hold.

[Andy Dingley]

On 25 Feb, 08:50, Tim Lamb wrote:

While we are here, has anyone a sub 99ukp auto darkening welding shield
to recommend?

SIP, the cheapie one.

[Tim Lamb[_2_]]

In message , Grimly
Curmudgeon writes
We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Richard saying
something like:

I had wondered about making accurate 90 deg corner plates at home and
taking those to site to use almost jig-like to ensure accuracy. Might
that work?

Of course.

Just check the diagonals are equal

regards

--
Tim Lamb

[RW[_4_]]

"Richard" wrote in message
...
I'm (fairly) good at sticking bits of trailer together with my MIG but
have never built anything from scratch.

Friend wants me to build him a light duty security door which will allow
him to prop the main door to an underground building open so as to allow
increased air flow but which exclude unwanted visitors. I guess that he
envisages something like a tennis court gate but with expanded sheet steel
in place of the chain link netting.

So, to the questions. Assuming that I make the frame and door from RSA
steel, how do ensure that everything stays flat and square as I weld it
up? Do I need more/fewer/different braces? How do I attach hinges and
locks? Any pointers to plans/instuctions on the web would be much
appreciated.

If you can why not cut the material to the correct lengths and prop it into
the door frame with spacers around it on each side, top and bottom.
Weld temporary bracing to it and tack the joins so that it can be manhandled
to a better place for welding properly. When at a suitable area you can add
the internal mesh and weld properly.

The advantage being that if you are near the site you can offer it up to
ensure a perfect fit and check where to add the hinges.

[Richard]

RW wrote:


If you can why not cut the material to the correct lengths and prop it into
the door frame with spacers around it on each side, top and bottom.
Weld temporary bracing to it and tack the joins so that it can be manhandled
to a better place for welding properly. When at a suitable area you can add
the internal mesh and weld properly.

The advantage being that if you are near the site you can offer it up to
ensure a perfect fit and check where to add the hinges.



Good idea.

[Dave Osborne]

Tim Lamb wrote:


While we are here, has anyone a sub 99ukp auto darkening welding shield
to recommend?


Tim, did you get this sorted? I just found this website. Haven't used
'em yet, but choice of auto-darkening helmets for well under a ton.

http://www.diywelding.co.uk

HTH Rumble

[Tim Lamb[_2_]]

In message , Dave Osborne
writes
Tim Lamb wrote:

While we are here, has anyone a sub 99ukp auto darkening welding
shield to recommend?


Tim, did you get this sorted? I just found this website. Haven't used
'em yet, but choice of auto-darkening helmets for well under a ton.

Not yet.

My birthday coincides with Christmas.

At those prices, I could get two:-)

Advice was to look for SIP version and elsewhere that battery operation
was safer.

thanks
--
Tim Lamb