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Driveway Gate Design Questions

10/29/2009 9:33 PM

i'm building a 3' tall, 11.5' long, single-swing, metal-framed driveway gate.

the gate will have two 2" x 4" wood (probably cedar) stringers anchored to it at the top and bottom and cedar dog-eared pickets appx. 4' tall (1' open area at bottom of gate, 5' installed height) attatched to the stringers.

i've got the appropriately sized gate automated opener to operate it.

i'm planning on using 2" x 2" square tubing on the frame.

i planning on having all-thread with a turnbuckle in the center running diagonally.

my question is with the gate frame design. i want it to be more than adequately strong to handle daily use year round, but not 'overkill' strong as with that comes excess weight. i'm thinking the gate will end up weighing in the 250 to 275 lb. area with the lumber attached.

so.... any educated opinions on tubing gauge (i'm thinking the frame might consist of different gauges) and frame design. below are a couple of designs which may or may not work. i'm open to what works the best.

* the post and hinges will be properly sized to my final design.

* i live in oklahoma. moderate wind. some snow. some rain.

* i've researched this for a few days before posting this - i've found a little info. here and a little info. there but not necessarily what i needed prior to buying my metal and starting my project.

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#1

Re: driveway gate design questions

10/29/2009 11:08 PM

Without doing actual calculations (just practical experience), I would use 1/8" (or 0.120) wall for the square tube frame. This is probably stronger than strictly necessary, but the extra thickness will make it easier to achieve strong welds. Another possibility for the diagonal would also be 2" tube rather than a turnbuckle. If you attach your pickets to the diagonal as well, they will also give up/down bracing to the relatively long horizontal members.

The key to this project will be strength and quality of anchorage of the hinge post. Say 3" pipe or square tube mounted in concrete?

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#23
In reply to #1

Re: driveway gate design questions

10/31/2009 12:56 PM

This sounds about right for the frame, but the idea that you will get any shear strength from the cedar might be wishful thinking. Cedar planks don't have much dimensional stability, and the fastener holes tend to get egged out pretty fast. Looks great though.

By the way, I never noticed that Oklahoma has'moderate wind'.

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#2

Re: driveway gate design questions

10/29/2009 11:47 PM

thank you for your response.

my hinge post is going to be 5" square tube, set in a squared 42" deep hole with a bricked-base. i'll have 2' to 3' outriggers (square tube welded to the base of the post @ a 90 degree angle to the post, 180 degrees opposite the gate when full open and full closed ). the post will have a few sticks of rebar welded to it above the outriggers and below grade. then concreted of-course. it's a free standing hinge post that won't be relying on any above grade, 'external-to-it' source of stabilization.

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#3
In reply to #2

Re: driveway gate design questions

10/30/2009 12:16 AM

My guess of 3" pipe or square tube would be borderline if a 250-lb person tries to take a 90-degree merry-go-round ride on the far end. Your choice is better. Nice project! As to your hinge details, have you considered something like Rulon bushings for the rotating surfaces, and a UHMW washer or the like for downward thrust? This will avoid squeaking of metallic contact surfaces.

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#4

Re: driveway gate design questions

10/30/2009 12:21 AM

I'm with Tornado here. Your choices of tubing wall thickness is rather limited with 1/16" and 1/8" the most common here in the US. I'd run the all thread from upper left to lower right as in your illustrations.

I'd consider gussets in each corner for some more strength.

Good luck!

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#5
In reply to #4

Re: driveway gate design questions

10/30/2009 12:52 AM

Good point! A turnbuckle arrangement must be in tension, as correctly pictured in the OP. Interestingly, a rigid diagonal in compression can work well even if the welds are doubtful, but a tension diagonal will avoid worries about bending or buckling of the member. Different strokes for different folks?

I actually have a pet peeve about gussets, which I think tend to be overrated (though they have their place). The bending moments at a joint are basically resisted by the moments of inertia of the connected elements. A gusset typically moves the critical cross-section a small distance from the corner, decreasing the lever arm by only a small percentage. In short, diagonal bracing works best if it reaches clear across the relevant quadrilateral.

I have seen various designs in which gussets have been inserted, and yet the remaining structure was almost as limp spaghetti as the original. If I want to initiate a thread on this topic, though, I will have to study up better on the math. That may have to germinate for a while. (Who was it that figured all this out in the first place--Gauss, Bernoulli, Euler,...??)

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#6
In reply to #5

Re: driveway gate design questions

10/30/2009 1:05 AM

Considering that without gussets you have only two inches of weld at each corner, I stand by my initial suggestion.

Cheers.

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#7
In reply to #6

Re: driveway gate design questions

10/30/2009 2:01 AM

This aspect seems correct; adding some weld areas would help to increase the strength near the joint itself (if needed). But it doesn't add strength to the usually slightly displaced location where the moment of inertia of the main element is the key question.

Now I will need to bone up on inserting drawings into these posts... I've gotten some good hints, but have not practiced on them yet.

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#36
In reply to #6

Re: driveway gate design questions

11/02/2009 10:51 AM

definitely going with gussets.

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#38
In reply to #36

Re: driveway gate design questions

11/02/2009 12:03 PM

I saw that in your updated drawing. #9.

As you can see most questions like this take on a life of their own.

There is never a lack of opinions here.

Good Luck.

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#8

Re: driveway gate design questions

10/30/2009 4:25 AM

I'd make it out of timber I lke timber,it's light and strong,(doesn't weld too well tho')
Baaad Kitty
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#9

Re: driveway gate design questions

10/30/2009 11:29 AM

here's the direction i think i'm going.

i'm going with the 2" x 2" - 1/8" wall thickness - square tube.

after i assemble it, i'm going to take it to be powder coated.

i'll post some pics in a few weeks or so.

* i'm buying the metal this morning but won't be doing any assembly until this weekend. i'm certainly still open to any further input.

*** what's the deal with the voting on answers? am i supposed to be doing that?

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#12
In reply to #9

Re: driveway gate design questions

10/30/2009 2:01 PM

The voting is an informal way to praise or scold the poster. It is not scientific, just a way to let someone know that they've given an answer that you think is Good.

Far too much emphisis is placed on GA's by some contributors.

Great presentation!

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#16
In reply to #9

Re: driveway gate design questions

10/31/2009 9:29 AM

Hello Mr. Horsepower:

This is a suggestion, but you may want to revise your design a little bit. Based on statics analysis, the configuration of your gate acts like a statically indeterminate horizontal truss. The top horizontal member will be in axial tension as well as bending due to the weight of the attached wooden fence pickets.The diagonal member (blue line) from the "Open End" of the gate to the lower hinge will be in axial compression. If you attach the wooden fence pickets to this member as well, it'll be bending too, vertically due to gravity; basically, this member is what is called a beam-column. You want to have a steel tube strong enough here because the laterally unsupported length is fairly large, and if the member isn't beefy enough it will buckle. Imagine a standard plastic straw placed between both of your pointer fingers and then press them together and see what happens. It basically folds in half, right. Now add to that compressive force made by your two fingers a gravity load all along the length of the straw, like someone else pulling downward on it, with the result being that it will buckle much much easier even if the pointer finger loads are decreased!Without running calculations or a FEA analysis, I'd suggest you use a structural steel tube such as a TS 4x6x 5/16 or even better, a TS 5x7x 5/16, with both tubes having a Yield Stress of Fy=46 Ksi.

Now the the other diagonal member, the one spanning from the open end of the gate to the upper hinge will be in tension, an is in my estimation sort of redundant since you already have the diagonal compression member taking a brunt of the loads. You can use a good quality steel cable w/ turnbuckle here because it would be ideal from time-to-time to make adjustments due to sagging, but you must also take into account extreme temperature swings that'll do strange stuff to your gate.

Now the bottom horizontal member is again in compression and also acts like a beam-column due to the weight of itself and the wooden fence pickets. Make this member as least as large as the structural steel tube that you'd be using for the diagonal member in compression.

Now the post with the hinges can be looked at two ways: One, freestanding and anchored into the soil with a concrete base, or two, a post that has a diagonal guy wire and turnbuckle going back around 18 feet or more and sufficiently anchored into the ground.

First, the free standing post: This has to be beefy enough to withstand the lateral loads acting on it from your gate members...the post will then act as a cantilevered beam sticking out of the ground vertically. this analysis will be valid as long as the concrete base is large enough and deep enough to transfer the bending and reactions into the soil mass. Think of a telephone pole with the Jolly Green Giant trying to push it over laterally, with one hand placed at the top of the pole and the other hand placed at the ground level of the pole. Without calculations, I'd suggest that you use at least a TS 8x6x 3/8 (Fy=46 Ksi) as the post with a concrete base no less than 6 or 7 feet deep and 2 feet in diameter.

Second choice is to have a diagonal guy anchor tied to the top of the post so as to transfer the upper lateral load acting at the top hinge. Probably can use a 1/4-inch steel galvanized cable w/ turnbuckle here. Also, with use of the guy wire you can probably reduce the the post size considerably to a TS 4x4x1/4 (Fy=46 Ksi). I'd still use the same sized concrete foundation as the other post option because you are relying on the passive resistance of the soil mass next to post......try not to disturb that soil too much, and if you do make sure you thoroughly compact any backfilled soil. I suggest using water as a the compactor...it'll sit up like concrete when it dries and will be very dense.

If you want, I could run a fast FEA structural analysis of the gate for you and come up with some member sizes. Just let me know by PM, okay?

signed off,

CaptMoosie

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#39
In reply to #16

Re: driveway gate design questions

11/02/2009 12:14 PM

you obviously spent some time on your reply. thanks for that.

i don't want to argue with any of what you're saying as i certainly don't have the ability to do so based on my own knowledge, but the size & gauge metal (for the frame or post) you recommend seem a little beefier than what i've seen in the research i've done (i will say that i haven't seen exactly the gate i'm trying to build that would allow me to copy their design).

it sounds like the structural analysis you offered to do would probably iron all of that out. i'm going to take you up on that offer and see what you come up with.

.

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#18
In reply to #9

Re: driveway gate design questions

10/31/2009 11:04 AM

In my opinion, the heavy extra diagonal running from the lower hinge corner to the upper free corner is adding weight without adding significant structural regidity. A heavier diagonal from the upper hinge corner to the lower free corner will give you a lighter structure overall.

Also, would a tall post on the hinge side, with a support from the top of the post down diagonally to the upper free corner interfere with the aesthetic effect you are striving for?

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#10

Re: driveway gate design questions

10/30/2009 12:48 PM

I just want to chime in and say thank you for the very well thought out, and extremely well presented question. It's not too often we get a question where the OP has actually taken the time to clearly present their situation. 5 star rating... bravo.

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#11
In reply to #10

Re: driveway gate design questions

10/30/2009 1:09 PM

..... thanks.

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#13

Re: Driveway Gate Design Questions

10/30/2009 3:15 PM

Hello, A couple of ideas to work with your design. First if the mounting post is extended several feet above the top of the gate you could have a diagonal chain/cable turnbuckle from the top of the post to the far end of the gate to prevent sag over time.

I had a couple of 4x12 gates made out of 2x6x12 fixed this way never had any problems opening or closing. I could even hang on the open end and swing with it. All 350lbs of my self. The gate was horizontal rails with anti-sag diagonal from top open end to bottom hinge side.

Second idea is a little over kill BUT... is to use an axle spindle with tapered bearings like in auto wheel hub. Ive seen these used in swing out tire carries on custom 4x4 bumpers. Northern tool axle spindle

To make a weld able adapter find a tubing to fit over the bearing race and another to fit inside to act as a spacer between the races.

Charles

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#37
In reply to #13

Re: Driveway Gate Design Questions

11/02/2009 10:56 AM

i agree with the design, i'm trying to not have anything protruding above the fence line though.

curious though as to whether or not yours was an open gate design (like a 3-rail) or had a face on it of sorts (like pickets) ?

* wow, 350 lbs. you sir are a big ol' boy. if a fight breaks out, i'll be right behind you.

.

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#44
In reply to #37

Re: Driveway Gate Design Questions

11/02/2009 5:19 PM

Open design, 4 rails top, bottom, two in the middle. Gate posts telephone poles 4ft in the ground no concrete. 11ft out of ground with top bar/pole across opening.

Ya behind me, way behind

Charles

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#14

Re: Driveway Gate Design Questions

10/30/2009 9:13 PM

picked up the metal for my post today. ended up going with 4" square tube, 1/4" wall. the hinge post is 9' tall.

tacked the outriggers on.

*originally, i'd said the outriggers would be 180 degrees opposite the gate full closed and gate full open position. that is incorrect. they will be pointed in the direction of the gate full closed and full open position - like how our feet keep us from falling forward even if we lean that way a little bit.

going to finish up the welds tomorrow and take the posts to be powder-coated on monday.

digging my holes this weekend also.

after i get my post set, i can make the final measurements for the gate.

thank you everyone for the responses. we'll get this thing built if it kills me, lol.

some pics -

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#20
In reply to #14

Re: Driveway Gate Design Questions

10/31/2009 11:52 AM

I would suggest using wire rope instead of "all thread" rod. Since you are using 4" tubing, your 2x4 is too narrow to attach to the tube. How do you intend attaching the wood to the tube? Avoid drilling holes into the tube. Some welding studs shot into the top and bottom tube rails, can be used to anchor the wood 2x4's, before powder coating.

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#41
In reply to #20

Re: Driveway Gate Design Questions

11/02/2009 12:31 PM

you know, i'm not quite sure how i plan to attach the 2" x 4" 's but i wasn't planning on drilling into the tube though.

i've seen some clamps that are used to attach wood to round pipe, i was hoping to use something like that.

.

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#47
In reply to #41

Re: Driveway Gate Design Questions

11/02/2009 9:48 PM

For fastening the stringers to the tube frame, there are square U-bolts that might do the job. They could be lined with a strip of gasket material to keep from marring the paint. I would look at counterboring the stringers to the diameter of a washer, and the depth of washer plus nut, so that the bolt ends can be cut off flush. Two near the ends of each stringers, and say two more equally spaced in between.

Your fence looks nice!

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#21
In reply to #14

Re: Driveway Gate Design Questions

10/31/2009 12:11 PM

Also by going with 4x4 tubing, the weight of the gate is now over 350# plus the weight of the wood. You might have to re-think the supporting post at the hinge end.

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#22
In reply to #21

Re: Driveway Gate Design Questions

10/31/2009 12:13 PM

picked up the metal for my post today. ended up going with 4" square tube, 1/4" wall.

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#15

Re: Driveway Gate Design Questions

10/30/2009 9:57 PM

Great drawings and pix! An interesting thing about the vertical picket design is that others can easily modify it by arches, scallops, waves, or other contours along the top. Nice bottom anchorage. How well does powder coat hold up in concrete? I don't know if that would be an issue, but if it is, a zinc-rich paint within the concrete and powder coat above ground might be a good combination.

You might want to echo this project onto the DIY forum, too. Everybody seems to be applauding.

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#17

Re: Driveway Gate Design Questions

10/31/2009 11:02 AM

I have read the other responses to your post. You have been provided with some very good advice. I have constructed a lot of gates for my cattle pastures and around some of the construction sites that I have worked on.

I offer you this simple bit of advice that comes from lots of experience. X brace the gate frame with the same size or just a little smaller sized steel tubing. This will help the gate from twisting in case it some how gets pushed from the top or bottom at the open end.

Incorporate in your design and construction the use of a wheel of sufficient strength to carry the weight of the open end of the gate. Eventually fatigue will come into play and the gate could sag, or the post on which it is hanging could move. Where you live the ground freezes and thaws, and movement of these kinds of structures is common place.

TMF

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#40
In reply to #17

Re: Driveway Gate Design Questions

11/02/2009 12:22 PM

i had wondered whether or not an x-braced design would work well.

curious as to whether or not any of the gates you mentioned had fence panels mounted on them?

.

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#19

Re: Driveway Gate Design Questions

10/31/2009 11:14 AM

Good show. Be sure to send pix when done. I'm anxious to see the end result.

I like the "feet", good idea. Hope you're not digging by hand.

Cheers from an Arkie.

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#24

Re: Driveway Gate Design Questions

10/31/2009 1:53 PM

Couple of good posts here..... . Sorry!

Captmoosie, and others. Incidentally the standard UK telephone posts
are only 4 feet into the ground - 7 ft will be well on the way to Aussies!

The (UK) telephone/telegraph posts come with a embossed marker at 10 feet
from the base (butt) - the inspector measures (usually by his own height) how
far this marker is from the ground (6 ft) to assess if the post is at the correct
depth. If the digging is hard, the only way to "cheat" this system is to saw a
couple of feet off the butt; - and hope no one ever has to climb it.
(been up there, and fell over.)

I think the detail of the op is unbelievably good, to be commended. Well done.
It's a pity about the rain... don't know what to do about that; some sort of hat
I guess.

There are several ways to "stay" the post. If from the top by wire, it can be braced out-wards at the middle of the post and tied in at the butt.
or a stay block having a vertical tie bar about 2 ft deep would be fine.

I would definitely allow a fraction for the weight of the gate, if it's only
half an inch off vertical, as the weight of the gate will pull it over.
To state the obvious, the post should be immaculately vertical in the
front-to back plane, (lateral?) unless it is intended to make it self closing!
(or self opening if leaning back towards the opening side.)

OK don't laugh - I have made self closing gates before... deliberately.

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#25

Re: Driveway Gate Design Questions

10/31/2009 2:54 PM

ps... one last bit of advice ...
When you have made your pride and joy, painted and completely installed it.
place a guarding post / block, to prevent anyone hitting it with their vehicle.

A driver, just carelessly turning their vehicle round in your entrance
can easily wreck your work, and just drive off. (I'm on my 3rd set of gates)
and even my side walls show the signs of many past vehicle conflicts.
(so much so I don't even care now; you may, after making it!)

jt.

Had a bloody surprise this morning, car smashed up my gate.
The fella got out of his car and he was a dwarf!! He said "I'm not Happy" ...
I said, " Well which one are you then?"...

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#26

Re: Driveway Gate Design Questions

10/31/2009 7:13 PM

The steel in this design weighs about 160 lb. Assuming 45 lb/ft3, the pickets weigh about 220 lb (depending on the spacing between). Add a bit for paint and screws, etc.; let's say 400 lb for the entire gate. Its CG is 5.5 ft from the post, hence a moment of 2200 ft-lb.

Where the gate abuts the post, the midpoint of the gate is ~2.75 feet above the anchorage. 2200/2.75 = 800 lb of sideways force on the anchor post. (Note, this is a thumbnail simplification, but it should be decently close.)

The post approximates a cantilever beam of length L = 47 inches, with a point load of 800 lb (F), 16 inches (a) from the end. Deflection D = F(2L3 - 3aL2 + a3)/6EI, where modulus of elasticity E = 29,000,000 and moment of inertia I = 8.22 for 4-inch 1/4-wall tube. This calculates to 0.059 inches. This, plus clearances in the hinging, will make the end of the gate sag maybe 1/4 inch or so. If an FEA (finite element analysis) is done, it will refine this quickie estimate.

Or you could simply mount the gate to the post before burying the post, and actually measure any sag. Then lean the post as needed to compensate.

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#27
In reply to #26

Re: Driveway Gate Design Questions

11/01/2009 12:54 AM

"OR" you can forget all about the weight of the gate and said weight impacting the stability of the post by simply placing a wheel at the open end of the gate. The beauty of this is that you don't have to be an engineer and calculate the stress/weight of the gate on the post except to no that your post has to stabilize the anchored end of said gate. "It's so easy even a "Cave Man" can do it".

TMF

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#42
In reply to #26

Re: Driveway Gate Design Questions

11/02/2009 12:47 PM

i'm going to do everything possible to keep the gates weight in the 250 lb. area. i'm going to go pick-up the wood for it in a few days, do some rough cuts on it and then weigh it. that way i can take at least some of the guesswork out of the equation.

your calculations look like the type of engineering that i came here for. i can't say i followed along as well as i'd like to, but it sure looks impressive.

i hope the more real world numbers i can provide to plug into those formulas will help to get more exacting figures (good input = good output, right?)

thanks.

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#45
In reply to #26

Re: Driveway Gate Design Questions

11/02/2009 7:52 PM

4x4x1/4 wall steel tube weighs 12.21#/ft.

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#28

Re: Driveway Gate Design Questions

11/01/2009 8:58 AM

I used to be in the business of installing automatic gate systems.

You are on the right track.

Please.. No turnbuckles .. no you won't need them.

As for the hinge post..

... concrete is the cheapest.. easiest.. simplest anchor.

A thin anchor post will twist at the start of the cycle if it's too thin, or anchored poorly.

The weight of your whole project is not as important as a smooth operating gate.

With your gate covered in wood, it becomes a sail, and THAT is your biggest load.

Oklahoma... a little wind!?

My relatives that live there spend part of the year in their underground tornado shelter.

..

and.. omg.. keep the wheels on the car and off the gate. Save that crap for armature hour.

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#29
In reply to #28

Re: Driveway Gate Design Questions

11/01/2009 9:17 AM

"Save that crap for armature hour." Did you mean amateur hour? Our did we switch over to an electric gate and I missed it?

I agree with no wheels. A properly installed system should support itself. The turnbuckle? I don't know.

Also, by now mr horsepower is starting to say to himself, "won't they ever quit and let me get back to work?"

Cheers

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#31
In reply to #29

Re: Driveway Gate Design Questions

11/01/2009 12:44 PM

Hello lynlynch,

I have gates on my cattle pasture that have remained maintenance free for at least 15 years. They all have a supporting wheel that rolls with the direction the gate swings. I also have some interior gates that go between pastures where the cattle travel. These gates did not get a wheel as the cattle traffic ruts away the areas all around said gate. therefore no contact with the ground would exist after a short time. "Therefore no wheels. These gates ultimately all will sag after a short while. To over come this, I construct a small ramp/skid that carries these gates when closed or fully opened either way. This reduced the continuous maintenance on these gates.

TMF

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#32
In reply to #31

Re: Driveway Gate Design Questions

11/01/2009 1:31 PM

Hi TMF,

I don't doubt you. However, I have knowledge of gates without wheels which have remained serviceable for years. Just depends on numerous factors.

Cheers.

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#33
In reply to #32

Re: Driveway Gate Design Questions

11/01/2009 2:13 PM

You can get the best of both worlds by mounting the wheel on the top edge, that way you don't need to worry about ruts and the wheel will remain serviceable.
Del

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#34
In reply to #33

Re: Driveway Gate Design Questions

11/01/2009 3:22 PM

Fur BALL!!!!!!!!!

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#30
In reply to #28

Re: Driveway Gate Design Questions

11/01/2009 12:33 PM

"KEEP THE WHEELS ON THE CAR AND OFF THE GATE"

"Sorry sucker"

We who have installed thousands of gates that swing from a single anchored point have long ago learned that long gates that are mounted E/W as closed and swing N/S when opened apply loads in at least three directions, open out and open in and static closed. At all times, described above there is a tremendous load on the top hinge of said gate. This load transfers to the post at that point. Leverage now has entered the equation. Said leverage is easiest over come by adding a support under the outer most end of said gate. AND: as said gate must move to open and close said movement is best accomplished by using a rolling apparatus. "Most of us call this a wheel."

TMF

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#46
In reply to #30

Re: Driveway Gate Design Questions

11/02/2009 8:09 PM

Did you read? Did you look at the dimensions of the gate?

It should NEVER need a wheel.

I have installed numerous gates with 20'+ openings that are still in operation ...without a wheel. Some gates have weighed in excess of 1 ton.

...but I've only personally installed maybe a few hundred system's.. not thousands.

...it's an engineering thing?

So again...

Use lots of concrete in your post hole...... How much for ~1/2 yard?

It's the best and cheapest way to ballast a gate... esp. one that is subject to wind loading as yours will be when covered in wood.

Use a sturdy hinge post wall thickness of... 1/4" MIN! 3/8" better.. 1/2" preferred.

Lay out the frame and weld it together on a flat surface with a piece of steel welded in place for the diagonal support. It does not have to be much, and it will do the Job continually without adjustment or stretching.

Weld a long piece of 1/4" X 4" flat stock in the area where the operator attaches to the gate.

...I would forgo the powder coating.. Proper prime and paint is very easy to maintain.

If you paint it, it will also allow you to temporarily weld the gate onto the hinge post in the closed position BEFORE you weld on the greaseable ball hinges. .... then you grind off the temporary supports. .. .. then everything is plumb and level... forever..

No gate systems are designed to open with snow in the way.

It's a safety thing

my 2

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#35

Re: Driveway Gate Design Questions

11/02/2009 2:54 AM

wow. i'm surprised by the number of responses. just wow.

thank you everyone, really.

ok - a couple of things (not in any specific order).

1. i found a website that has quite a bit of good info that applies to my project.

1a. - a gate installation video - http://www.gatedepot.com/video/swing_gate_1/Swing%20Gate_player.swf

1b. - outrigger installation detailed - http://www.gatedepot.com/diagrams/detail/outrigger.php

2. my goal is to build the lightest gate possible that meets all of the structural/environmental loads placed on it. i'd like it to look as close to a normal picket fence as possible.

3. i'm not as smart as some of you obviously are.

4. cedar wood has varying densities.

my questions/comments regarding these items.

1a. - they appear to know what they're doing. i'm probably using this as my post/gate installation guide.

1b. - it appears that i have incorrectly located my outriggers. after looking at their recommendations, it makes sense to me how the higher location would brace the post better. i've got some additional 4" square tube that will allow me to install the outriggers as they've shown - i'm wondering if the outriggers i've already welded to the base of the post could help any (at best) or at least not be detrimental to the post stability (at worst) ?

2. if i'm building something and i want to make it stronger, i normally add to it (if it's made of wood - more wood. if it's made of steel - more steel. ....) you know, if a little is good, then a little more is great. i realize that strength comes from proper construction too - strategically placing less material.

all feedback is appreciated, all feedback helping me to correctly design and not overbuild the gate is really appreciated.

also, i'm not opposed to using a wheel on the gate. i'd rather not, but i would.

3. i research things often and quickly find that the little bit more i now know has opened my eyes to the fact i don't know sh*t.

some of the replies are compounding that feeling, lol - when possible guys, 'dumb it down' just a little to keep your efforts from being wasted.

4. from adding on to the existing fence last weekend

(cedar everything) and handpicking all of the lumber, i was reminded of how greatly the weight of cedar can vary comparing like cuts of boards.

i want to handpick all of the lightest boards for the gate (for obvious reasons). does anybody know if the lighter boards act more like a sponge when exposed to moisture as compared to the denser, heavier boards? if so, sealing the boards would be the answer - right?

.

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#43

Re: Driveway Gate Design Questions

11/02/2009 3:10 PM

One after thought - allow for the swinger!

It's not unknown for people to climb over gates.
OK they open, - but some like to climb over, and, some
times like to have a "swing" - so allow for a little "over-weight?"

jt.

A guy admired my gold pocket watch, and asked me, "where did I get it?"
I replied, "on his death bed, my grandfather sold me this watch."

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#48

Re: Driveway Gate Design Questions

11/03/2009 4:22 AM

i'm thinking that by getting rid of the 2" x 4" stringers mounted on the fence frame and instead mounting the pickets directly to it, the load on the post will be decreased considerably.

my thoughts on how to do this were to braze small bolts to the face of the frame, drill bolt holes in the pickets and install them with a flat washer, lock-washer and a cap nut.

it wouldn't take me too terribly long to do and the pickets would be easily replaceable if they were to get damaged.

it'd look something like this -

again, thanks everyone for your input. i'll post some pictures of any progress i find time for this week.

.

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#50
In reply to #48

Re: Driveway Gate Design Questions

11/03/2009 10:21 PM

yeah, i'd certainly thought of that and i agree it'd be easier. my thinking is that the frame would rust more easily with all of the additional holes in it.

i'm going to have drain holes drilled in a few spots as needed though, so maybe it wouldn't be as big a deal as i'm thinking it would be.

.

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#49

Re: Driveway Gate Design Questions

11/03/2009 11:13 AM

On your hinge post Use 4 inch pipe buried three feet in concrete. If you want to be sure the post never moves, move back 3 or 4 feet from your gate post and put in another post with a horizontal bar welded on the top and one towards the bottom. If that is not good enough you can bury a " dead man" and wire that to your gate post, it will run diagonally toward your second post and into the ground where you have buried your dead man(rock) that post will never move.

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#51

Re: Driveway Gate Design Questions

11/08/2009 9:36 PM

hi guys. here are some pics of where i'm at. plus, still/also looking for some educated opinions on a few things.

where the gate is being installed -

a few looks down into the hole -

3' x 3' hole, 4' deep, 1' tunnels or reliefs for the post feet or outriggers.

hinge post 4" square tube, 1/4" wall, 9' tall (4' below, 5' above)

my questions -

1. i'm planning on tacking the rebar onto the post as sticks, some going n/s, some going e/w, keeping them from being too close to the top, bottom and sides. will this work as well as building a few rebar loops (cages) around the post?

2. the opinions (from here) vary as to the gate frame design. would most everyone at least agree that if the gate were built with an x-braced frame (with same 2" square tube, corner to corner) that it should be sufficiently strong for it's purpose ?

3. is there any benefit to compensating for gate sag with hinge post placement vs. having a perfectly level post with adjustable hinges for the gate ? use both methods maybe ?

* calling concrete company tomorrow to get in line for a load (if they'll sell me (just) 1.5 to 2 yards delivered. will have to get one of those dump trailers you pull yourself that hold 1 yard if not.

thanks again guys.

.

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#52
In reply to #51

Re: Driveway Gate Design Questions

11/08/2009 11:48 PM

1. In your case. Yes. This would be the popular and acceptable route. there is not a big load on the concrete, and there is little chance that any chunks may break away and fall off...

... taking care not to touch the sides with the rebar is also a nice touch. Such a good idea for long term preservation that many would overlook underground.

2. If it were my gate I think I would use four 27" verticals evenly spaced with my 13.5 footers as the top / bottom rail. As for the diagonal bracing... I don't see a need for an X... The top to bottom piece that starts at the hinge post will suffice on a 2" square tube frame. It is still light and strong enough at that size to be pretty stiff. I would not trying to hitch a ride on it, but it will be about that tough...

once you attach the pickets.. what do they say? forget about it?

3. Keep the hinge post level.

Weld the gate onto the hinge post PRIOR to installing the hinges and yes.. raise the end of the gate about an inch above level. The gate will settle a bit when you cut away the temporary supports largely because of play in whatever hinge you are mounting, and partly due to the weight of the gate on that long narrow leaf. and just a little bit more over time..

...It won't be enough to matter to the operator.

* Good idea to have a place to put the extra concrete, but remember.. you might have the guy for 30 min to do 5 minutes work.

look for a neighbor with a rough patch of sidewalk in his back yard... like me! I'll run my wheel barrel over 2/3/4 times AND dump the extra extra..

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#53
In reply to #52

Re: Driveway Gate Design Questions

11/09/2009 1:06 AM

"As for the diagonal bracing... I don't see a need for an X... The top to bottom piece that starts at the hinge post will suffice on a 2" square tube frame."

regarding the 'top to bottom piece', were you referring to just the vertical square tube on the hinge side or the diagonal wire-rope or all-thread with a turnbuckle in it that i mentioned using in my first couple of post ?

also, what's your opinion regarding the construction of the corners of the frame (pictures shown do not show gussets which i plan on installing) -

any opinions on the hinges ? as i'm sure you know, there are several designs to choose from. here's a link to a page that has several different designs.

http://www.gatedepot.com/sales_hardware_swing.php

thank you for your expertise.

if you lived anywhere close, i'd gladly give you any excess concrete i might end up with - lol.

.

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#54
In reply to #53

Re: Driveway Gate Design Questions

11/09/2009 7:15 AM

I was referring to the piece that is diagonal.

I would weld a piece of steel, ... 1/2" X 1/2" square stock.

I would NOT put in something adjustable.. It will not need it..

I like the block hinges... any size will work .. forever..

I would use the #1 stale of frame building.. gusset free..

... I would rather have 4 pieces. going up and down instead of three.

... thanks for the concrete offer..

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#55

Re: Driveway Gate Design Questions

11/09/2009 9:51 AM

Three advantage of the mitered corners:

1. Inside of tube is sealed off, not exposed to weather.

2. More total length of weld at each corner (9.7" versus 8").

3. More aesthetic (but that's just opinion).

___

The adjustable hinges mentioned in a previous post are a great idea, better than my earlier idea of leaning the post to compensate for gate sag. Your post burying detail and pic look good.

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#56

Re: Driveway Gate Design Questions

11/12/2009 11:32 PM

tonight i leveled the bottom of the hole with cinder blocks (broken in half), trenched around them slightly and filled that area with pea gravel.

then, i put the post back in place and welded my rebar to it.

the concrete is being delivered saturday morning. after the first yard, they only charge for what you get - 2 yards is going to be $300 (including a $20 tip for the driver).

when i make some more progress, i'll post some more pictures.

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#57

Re: Driveway Gate Design Questions

11/20/2009 5:58 PM

concrete was delivered saturday morning.

it took 1.5 yards to fill both post holes.

the price was ONLY $170. ( this is a DEAL. it would have taken appx. 70 - 80lb. bags to make 1.5 yards. i wouldn't have poured 70 bags of concrete if someone had given them to me and stacked them right next to the holes for $170. )

the truck that showed up was pretty cool (i'd never seen one like it anyway). it carries dry concrete and water separately, mixes them together at the back of the truck. quickly too. 1 second after it's in the mixer it's coming down the chute.

* my crawling in and out of the hole is what makes the hole look to be round. it's squared for sure.

hinges are ordered, should be in on monday.

i'm building the gate frame currently.

i'll post some more pics when i've made further progress.

thanks again everybody.

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