Making Curved Hinges for Oak Gate

[ScottyT]

i am currently nearing the end of making some hinges for a fairly big gate as far as pedestrian gates go.
I haven’t documented the making of the gate as it differs very little to a previous post I put up here on the same theme, and it’s a bit of a ‘you’ve seen one you’ve seen em’ all’ kinda style.
That said it does have a top rail that includes the curve and capping in one hit, I’ll explain a little more about that further down the thread.

I do my own metal work as it keeps me in control, I enjoy it, it breaks the weeks up a bit from the woodwork and I feel the joinery background crosses over hugely into metal fabrication, things like marking and measuring accurately, practical thinking and the approach to the task is all the same or similar.
I have only basic tools which is all I need for what I do, consisting of a good quality MIG welder, an angle grinder, various clamps, a selection of hammers and holding tools, a forge and anvil (the anvil is just about ok to use it has seen better days but does a job until I can get my hands on something in better shape) and a metal bench I made for working on.
I also have a lathe that’s invaluable in my home workshop that I use for keeping my old motorcycles on the road, brought years before I started metalworking but comes in handy all the time!

Basic overview for this job is a curved top rail, with really quite a tight radius cut into it, and a straight bottom hinge for the bottom rail.

Here’s the template for the top rail of the gate, my top hinge will need to follow this radius, it’s quite tight but more than doable with a bit of patience.
First up is to get some heat going to aid in bending the metal, it’s ideal weather for it too as it’s been fair cold this week in the south west of England, beats the rain any day though.

The forge I have is fed air from an electric fan, and is controlled on a simple slide gate that increases or reduces flow depending on gate position. Once I have the metal hot I can set a bout starting the bend.
To start the bend I put the metal on the anvil and strike one edge, this forces the metal to stretch along its length, and as it’s only stretching on one side it will start to form a radius
This is shown In the below photo

I don’t want to hit it too much as it’ll get too thin so I use the horn of the anvil to really manipulate the curve, being careful to not totally distort the material in doing so. I just keeping heating the metal and have a few blows on it and the repeat repeat repeat until the desired radius is achieved.

Once both curves are done I can get them on the template fabricate the rest of hinge.

They follow the template pretty well, it’s a awkward one this as the top straight sections are 6” wide and diminish to 5” though the bottom of the curve then increase again to 6” on the following side. Still, nothing major just something to be aware of. Thee above photo shows to score lines for cutting, and the photo below shows them after cutting, ready to receive the next piece.

The ends of the hinge have this detail on them, a homemade scribe, mdf template and the angle grinder cracks these out in no time, I have beaten a similar detail to this in the past with the hammer and anvil, but these need to remain flat to match an existing pair of gates the client already has.

Next up is some welding.

 

[Trafalgar]

Fascinating stuff. Thanks.

 

[ScottyT]

Setting up for MIG welding is fairly straightforward, I stick weld when I’m on site as it’s way more convenient but in the workshop I always MIG weld unless it’s massive stuff.
I am using 6mm bright mild, so it’s really soft, dead easy to drill and great to weld, i first grind 45 bevels on each piece, clean the immediate weld area to get rid of contaminants and then that’s pretty much that, point and shoot.

Before I do anymore welding I need to drill both sets of the hinges, 10.5mm dia to take M10 bolts that’ll eventually hold all this to the gate.
It’s mild steel so easy to drill I double them up and do both at the same time for both sets, it’s fast and it’s as accurate as I’ll ever get it .

First up is a 6mm drill bit, goes through easy and is an ideal size for the 10.5 to follow. This is just a standard startrite wood pillar drill, but set to 350 it’s very capable of drilling mild and stainless, I’ve had no problems up to 22mm!
I use CT-90 cutting fluid, works a treat for drilling and a must for tapping! Lasts an age and keeps drill bits in great order! See below for details

Drilling out the final size ready for welding the two together.

With everything drilled out and ready to go, i measured my gate and then thicknessed a piece of timber down to +1mm over size, this will be my clamping jig to ensure a nice slide on fit when the hinges are all painted up etc.

Both sides of the hinge, the side tab and the jig all ready for the welder.
Once I’m happy with the set up on the welder, I clamp in place ensuring everything is flat and square and lining up, and then tac it all up.

 

[ScottyT]

Ready to go

First pass

The curved top hinge gets its tacs, once I’m happy it all works I just run the welds.

Smoothed up and ready for the next stage.

Both sets welded up. Now it’s on to actually working out the actual mechanics of it fitting from post to stile.

 

[ScottyT]

Over to my garage now, I have no woodworking tools at home what so ever but I do have some kit for metalworking.
I need to make the bracket assembly now that will fix the hinges I’ve made to the posts of the gate, the posts are 6x6 or very close to it and the gate in question does weigh a
fair bit so it needs to be up to it.
I have reams of cast material and odds and sods at home so I use whatever comes to hand that’s suitable
Below is 2” piece just right for the job

I cut this in half and it’s the ideal length to Chuck up in the lathe and turn what I need. I’m going for a 5/8” pin so I’ll bore it to suit.

Face up the end and then proceed to turn down to the O/D

Once I get down to O/D I can centre drill, drill and then bore to final size.

These will end up on the hinges once I have worked out their position, I have got them at 60mm in length, the same width as the hinge. I’ll come back to these later.
The pins that’ll hold all this will be fixed to 2x1 piece of mild steel of as yet an unconfirmed length so i just cut them long for now, the only thing that won’t be painted is the pins, so I’ll do them in stainless steel!

Above is the 2x1 pin carrier, that’ll in turn be welded to a plate that will be coach screwed to the post. It’s two pieces of 1” square bar that I’ve welded together, and i have drilled them 14mm to take the a 16mm piece of S/S bar, I just turn a shoulder 20 mil long on the bar to fit nice and snug in the 14mm hole, weld up the bottom and grind clean it’s nice and strong and looks tidy. Photo below shows the shoulder being turned for the pin.

The gate is hung flush with the posts on the backside, so I need these hinges to be ‘cranked’ for that to be possible, in the simplest terms I need to accommodate the projection of the pin from the face of the post with a metal bracket that will be joined to my hinges, it will have two bends in it to make this work, as shown below

I run slits in the metal then bend it, when I’m happy with the angles I weld the slits up and grind it off.

Better shown here, I have made one now I’m using that as a template to make the other, I am nearing the stage of doing a crude mock up to see where things land.

 

[ScottyT]

I’ll next post up in the week, it’ll probably (hopefully) all be swinging and looking good in a few days.

 

[Cabinetman]

I’m not a metalworker but still found it very interesting, thank you for the wip.
Ian

 

[carpenteire2009]

Wonderful work and a lovely setup you have! I got some blacksmithing exposure on a one day course I did years ago and loved it. Looking forward to seeing the finished work.

 

[foxbat]

Fabulous stuff and a lucky client to have everything made in one place, the quality control you have over the whole project is great to see, thankyou for posting

 

[niall Y]

Great hinges, after all that effort I would want these hot dip galvanized.

 

[Phil Pascoe]

Just about to post the same.

 

[ScottyT]

Next up is to finish up the various components ready for trigging it all up. Here is my gate to lash all of this together.

Fairly straightforward, made all the easier being made of oak, the only slight curve ball is the ‘capping that isn’t really capping’ on the top, we decided it was a lot less hassle to incorporate the capping with the top rail, rather than have it separate. Machining it out would have been a pain with some short grain to deal with so the top rail is actually full length across, and only tennoned to the last 1,1/4”, better shown below.

Note the same grain as the rail, a router and template was used to ‘break’ the joint here to mimic capping, all looks good and as stated much easier than machining separate capping from scratch.
I machined the T&G specifically to size so it’s all the same size showing, I really don’t like working from centre and ending up with odd sizes.

First up was to slap the hinges on and see the landscape, make a few tweaks if needed and then drill them out for fitting.

Not perfect but a few little tweaks with the grinder makes it a little better all around.

The above photo shows the gate drilled and the hinges fitted with a few tweaks to suit the final position, all in all we’re heading in the right direction here. I am in the top workshop here as all my metal working kit is next to it, and it’s a pretty flat floor so I can lay it all down in hear, get the welder in and tac it up when it’s all trigged.

Cranked brackets rested on the hinges extending over to where the pins will
be. with it all running through nice and trued up and flat, I need to mark and drill the bracket and weld it to my hinge, I place it where I feel it’s best suited and crack on from there.

Once drilled I grind some nice fat 45’s on both the bracket and hinge (above) to fill up with weld, it’s bolted through too so nice and strong.

I’ve filled it right up and then grind smooth, i score a neat line back up through the joint to make it a little easier on the eye and that’s that, I’ll post a photo of that tomorrow

It’s just the pins on the post section that need doing now.

Here is a rough dry run of the general remit, these need working out to length from the plate, prepped for welding and tidied up before I put the torch to them.

 

[ScottyT]

I sorted the pins out on there carrying plates, ground some nice 45s on there to take a good couple of passes with the welder and made them all up, it’s a case of laying up the gate with the posts on a level deck and trigging it all up for final finishing.

These land central to my 6” posts, so I lay it all down, place it all on loose so I can mark where to cut my cranked hinge bracket.

I just used a square and a scribe to mark the line where my finger is, I’ll cut this on that line and that’s where the socket will get welded. It really is job done then.

Top and bottom are now cut, I tack welded it in situ, took the hinges off the gate and back out on the bench and fully welded it up

A bit of two part filler to round out the joint over the ground back welds, once painted it should all look fairly seamless.

Above is the gate hung on its hanging post, I can see if it’s all working as it should be. Not my cup of tea on the design front but both jobs went well and came together as one well. I machined some post caps for this job too that are really quite large, I did them In two, one fits to the post, the other fits to that and I shall pop some lead over the top of that to protect it.

A little short video showing it swing. Works a treat.
Hope you enjoyed this post, i will put a photo up of it when it’s all painted up and installed.

Scotty

 

[paulrbarnard]

Looks great but I agree with Phil that those hinges deserve a hot dip.

 

[ScottyT]

Looks great but I agree with Phil that those hinges deserve a hot dip.

Thanks Paul appreciate the interest, I was going to reply to Niall & Phil on that, sounds good and would probably offer the best form of protection!
I use this stuff

It has a good coat of this, which is really good stuff in my experience, and then 2 coats of black over the top (top coats are sprayed)

 

[foxbat]

Lovely stuff Scotty!

 

[Inspector]

A pair of those would make great saloon doors for giant cowboys.

Kidding aside. Really nice work.

Pete

 

[ScottyT]

A pair of those would make great saloon doors for giant cowboys.

Kidding aside. Really nice work.

Pete

Thanks for the interest Pete

 

[Wood4me]

Wow, absolutely brilliant work, and you have documented the whole process so thoroughly that the reader just 'feels' your dedication to quality.
It leaves me wanting to know more about the install situation, I am assuming for a client ? and you have made similar gates before. What I don't understand is the issue of mild steel and oak and how the gates will appear in a year or two. galvanising may help but you have said you paint the metal, presumably before fitting on the gates ? Do you 'warn' the client about potential black staining ? The holes where the upright rails fit seem a risk area for black tannins etc. Also from bolts and hinge contact areas.
What has your experience been with gates that have been installed for a while ? Have you considered working in Stainless steel, accepting that would be a massive change in processes etc? You must have mulled all these aspects around and would be good to hear your decision process. Thanks for posting this project.

 

[ScottyT]

Wow, absolutely brilliant work, and you have documented the whole process so thoroughly that the reader just 'feels' your dedication to quality.
It leaves me wanting to know more about the install situation, I am assuming for a client ? and you have made similar gates before. What I don't understand is the issue of mild steel and oak and how the gates will appear in a year or two. galvanising may help but you have said you paint the metal, presumably before fitting on the gates ? Do you 'warn' the client about potential black staining ? The holes where the upright rails fit seem a risk area for black tannins etc. Also from bolts and hinge contact areas.
What has your experience been with gates that have been installed for a while ? Have you considered working in Stainless steel, accepting that would be a massive change in processes etc? You must have mulled all these aspects around and would be good to hear your decision process. Thanks for posting this project.

Thankyou, I’m pleased you enjoyed the thread and found it of some interest.
This is for a client yes, and I have made a few gates/doors in my time.
I do fabricate in stainless steel, I make quite a bit of door furniture like stays, drop bolts, handles, straight hinges etc and also lots of brackets and supports, but it’s job specific so changes depending on the spec. I would say it’s not far off 50/50 for mild and stainless usage wise.
care needs to be taken when welding it though, putting heat into it causes it to bend and warp.
TIG welding gives more control for S/S.
When I am forging I don’t use stainless steel as I can’t work it well, and doesn’t really lend itself well for the more traditional work.

The spiral bars fitted in the gate are dipped an inch either end in Kurust, then dipped in Zinc rich primer and then painted with the zinc all over then two top coats of metal paint. The holes in the rails are end grain sealed, then frame seal goes in when the bars are fitted in during final assembly. This is pretty much standard practice even if it’s not Oak.
To date there has never been any issues with the clients on staining (doesn’t necessarily mean it doesn’t do it) or issues with the metal being eaten up or dropping off.
The hinges are bolted using all stainless steel hardware, but again we use S/S for everything regardless of timber being used.
The only problems I’ve never had are with Accoya!
Thanks again

Scotty