Need help planning a build for a small boat dock!

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A friend of mine wants to build a dock for their lake house. The only use that it's going to get is for a pontoon boat, so it should be pretty small in size. I haven't built any docks or anything related to it but I'm sure I can do it with the right amount of planning, which is why I'm posting this thread. I will need to compile a list of what I will need as far as tools, materials, supplies (screws, strapping, etc) and so on. I'd like to come up with a step-by-step plan, I will probably be fabricating/assembling the dock myself, so I know that the thing will be done right and that it will last for the years to come because I'm sure if my friend hires anyone else she knows it will just fall apart after a winter season or two.If anybody has their own dock projects that they have done it the past, please feel free to show pictures and share your experience with your builds. I will be back to add specifics later, looking forward to getting this started!
Reply:I design and build marinas. A couple questions. Does the water level change a lot, in other words how often will it be moved? A good place to start is a Merco Marine catalog. It is full of ideas and plans. You also need to decide how high you want the deck to be above the water. Will it be free floating or fixed at an unadjustable level? What's the worst weather you can expect?  Are there codes for docks regarding floats, pressure treated lumber etc in that area?
Reply:The water level will change throughout summer and fall, I wouldn't expect it to fall and rise alot but I would say give or take a metre or so. It won't be moving at all, it will stay in the same spot. The worst weather is probably bad thunderstorms with heavy rainfall but nothing drastic, I live in Manitoba, Canada so the weather is usually pretty good but it does get super cold in the winter months as cold as -40. There isn't any code, it's remote and I don't think we need to worry about anything along those lines. I'm thinking it size, around 4'x8' or possible 8'x8'. It doesn't need to get huge, just big enough for somebody who doesn't have great mobility. They are fairly old, so the main reason why they want a dock is to be able to have access to the pontoon boat. The water line is at the bottom of a bank, so I'm thinking they will also need some kind of ramp to access the dock as well? As far as free floating or fixed, I'm not really sure, I think they would like to go with free floating, as they have it in their mind that they will need to use some sort of barrels to support the dock itself. Water depth is probably around 5' with a soft bottom, no rocks mainly thick mud and weeds.As far as winter season, is it better to remove a small dock like this or is it safe to leave it in the water through the freeze?Last edited by Tat2dHandz; 08-05-2014 at 06:48 PM.
Reply:Ice is a powerful thing. I've seen it uproot pilings of wooden piers that have lasted for years when the bay freezes over when it's an exceptionally cold year. Combine the rise and fall of water levels with the grip of ice and it jacks them up like you would pull weeds.I've also seen the ground freeze and heave concrete slabs weighing tons several inches into the air. I'm taking 6 or 8 inches, as well as blow apart concrete and block walls.I'm betting if the water is moderately shallow, and the temps are that cold, that you'd best plan on being able to pull the dock some how in winter..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:You are right. That's what I was thinking but I wasn't for sure.So as far as free floating vs fixed I would think that free floating would be the way to go. I've seen some docks with poles that allow the dock to rise and fall with the water level? How are these poles secured, are they just hammered into the bottom as far as they can go? How far should a support pole go down to be considered safe and steady? I don't know if the "customer" wants to buy any other kind of floating support, they already have 6 barrels and they have it set in their mind that these are what is to be used for supporting the docks weight. I have a good idea of how to build the frame, once I get the size of the dock chosen. I would probably want to go with some kind of pressure treated wood, would going with PT prevent having to go back in a year + and replacing the wood versus not using PT wood?
Reply:When I was a kid  in Conn. the lake had all floating docks, swim floats .They were wood  with some steel strap an other reinforcement  steel drums for floats Use plastic now  ,and put some skids on the bottom  so they will slide out of the water easy,anchored with blocks of concrete and chain on deep end and sliding poles near shore line . You can sink them with a water pump and hose  if the bottom is sandy gravel, That's my idea for what it's worthGeorge
Reply:Here ya go..Easy enough to make and can be taken out and put back in with 1 person..http://weldingweb.com/vbb/showthread.php...highlight=dockThe dock frame and such is on page 2..The stand for the end is on page 1..You'll figure it out....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:This design is easy to build. I've been involved in building several of them on the west coast.  Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:That's uh, way too big and I think you know that. But thanks anyways, good luck.I'm now in the process of coming up with a material list, and an estimate for total cost. I'm pretty sure I have a good solid build plan, I'll post everything I have when I'm done with all of the planning here. Anybody else with any input or past builds/experiences? Please, share your thoughts. Thanks.
Reply:Originally Posted by zapsterHere ya go..Easy enough to make and can be taken out and put back in with 1 person..http://weldingweb.com/vbb/showthread.php...highlight=dockThe dock frame and such is on page 2..The stand for the end is on page 1..You'll figure it out....zap!
Reply:OK, I get the picture.  Float the dock.  Use Merco as a guide on how high it will all float etc.  I'll try to post a pic of my "handicapped access" which were made state code after I outfitted all my docks with them. With Ice, I would take out as much as you can.  If you want to put pilings in, Just use a water pump jet and  downward pressure with a backhoe, excavator etc on the piling.  it will blow the mud away from the piling until it hit solid bedrock and will backfill by itself. Attached Images
Reply:blackbart: Do you think that pressure treated wood would last at least a few years? Is that plastic lumber you have in your picture quality? How expensive is it?Thanks, you've been a great help with this project so far. I'm sure that this will turn out better now than what I had in mind before posting this for help.
Reply:believe the trade name for that lumber is trex and yeah treated lumber will last for some time. When you build use hot dip galvanized ring shank nails, they won't back out like the spiral ones do. If you go with the trex remember to pre drill before you try an run a screw through it, helps tremendously.93 Bobcat 225GMillerMatic 135HF Tig 91811
Reply:I've decided to use Trex for the top. 4'x8' dock in size, now I'm trying to choose what to build the frame out of. Aluminum or mild steel? I don't think stainless would be ideal as this person is trying keep costs relatively low. I'd like to get the frame fabricated before picking up any Trex.
Reply:2"x2"x1/8" angle will work fine if you frame it right. It's not so thick that you can still screw through it with TEK screws.
Reply:Here are a few I made. Currently there are 3 sections of these tied together, holding 21ft bayliner on one side at 2 jet skis on the other. I was tuning the carbs on one ski with it roped to the dock and dock didn't even budge at wot on the ski. That's a lot of torque on them. "My ski, my dock, my torture test" as they're were some doubts on the design being to weak. These types of docks are very popular in the NE for the ease of removal and installation. By far mine are stronger than others I have looked at on the commercial market. 1"x3"x 1/8 on outer rails and cross rails, 1"x2"x1/8 ctr support, 1/8"x1" angle for deck boards to rest on for the outer rails.
Reply:​sbchp355​What kind of aluminum did you use? Is it expensive? I'd like to use material that will last, not sure whether to go with mild steel or aluminum. Majority of the dock builds I've researched in the size range we are going to build have been built with aluminum, and mild steel being used in bigger layouts. How much did your material cost for one section?
Reply:Floating 4x8 is very tippy. Go at least 6' wide. I attach trex directly to steel with floortorx screws, 5/16"x2-1/2". Regular tek screws break in a year or so. If you build the frame out of tube it won't flex. So it will feel solid for an older user. A dock out of channel or angle will twist and feel unstable, unless you X brace or truss it. Tubing will be much simpler for the size you are talking about. Make sure you drill drainage holes, ice on the inside will round out your tubing. Invest in the Merco type floats, you're only talking about 4 of them. You can probably drag the dock up the bank on the floats, they are very durable. If you overhang your trex it becomes a decent run rail. Did you get a Merco catalog?  Many of the floats are UPSable.  I would use 2x4x3/16 tube for the rim and 2x2x1/8 tube on 24" centers for the interior. Built basically like a ladder. Paint it with a couple coats of rust oleum damp proof or rusty metal primer, no finish coat needed. Deck it with any 2x6 material, trex or PT lumber. I will post pictures once my computer is repaired. I'm on a phone now so my pics are in the shop.Last edited by blackbart; 08-26-2014 at 10:20 PM.
Reply:Those are 4x10 made with 6061 aluminum. Light weight,strong, and stable. I recently had two jetskis sideways and two adults both over 200lbs on one section. Well over 1000  lbs in the middle of one section. These are fast to put in and take down. Winter destroys docks in vt. However they are designed  for a semi shallow area. I had them in water in the 6 to 8 ft range with good stability. The water bottom must be semi solid. The way my leg system works is that the poles are adjustable at two locations. There is a collar with pinch bolt that the mount sits on and a 12"x12" foot with a pinch bolt that sits on the lake floor and I have the pole go through the foot about 12 " into the lake bottom. "Good luck separating all the foot/12in. points in the last sentence. Heck I wrote it and had to read it twice". Also the lakes in VT don't really vary much in level. For conditions beyond what I have described you will need floats and couldn't agree more with black bart 4' is too narrow.Last edited by KD Welding; 08-26-2014 at 11:39 PM.
Reply:The design you showed in the picture is very stable for one with pilings like shown. However if it was floating, and only stable at the shore it would twist when walking on it. I have two side by side 6'x60' launch ramp floating docks. One is similar to yours, channel and angle, the second is tubing. It may not be excessive at 8' like he's talking about, but by the time you get out longer, I consider the amount of twist unacceptable for older folks.    One option for as small as he's talking is to build a wedge shaped "trailer" that can be pulled out. The wheels act as pilings and the other end secured to shore.
Reply:Originally Posted by blackbartThe design you showed in the picture is very stable for one with pilings like shown. However if it was floating, and only stable at the shore it would twist when walking on it. I have two side by side 6'x60' launch ramp floating docks. One is similar to yours, channel and angle, the second is tubing. It may not be excessive at 8' like he's talking about, but by the time you get out longer, I consider the amount of twist unacceptable for older folks.    One option for as small as he's talking is to build a wedge shaped "trailer" that can be pulled out. The wheels act as pilings and the other end secured to shore.
Reply:Originally Posted by sbchp355I think you idea sounds good. To the OP take what ever advise Blackbart gives you. He has a huge amount of knowledge on this topic. He has turned me on to a few different resources that have made life much easier.
Reply:You see a bunch of trailer type ones out my way. There are a few commercial manufactures. Most of them are design so you can add axels and extra sections. But pretty light weight design. Would work decent for him tough.Last edited by KD Welding; 08-28-2014 at 05:21 PM.
Reply:Originally Posted by sbchp355You see a bunch of trailer type ones out my way. There are a few commercial manufactures. Most of them are design so you can add axels and extra sections. But pretty light weight design. Would work decent for him tough.
Reply:I am all for the wedge trailer design Saw a bunch of then up at Deep Creek Lake in W. Maryland . Some even had  screen houses  on them. Just buy Axle stubs from Northern Tool or some such place Make then as wide as you want and if you are really cutting cost you don't even need tires on the wheel rims , It is only going to move 40' a year and if you think that the dock will move with the wave action build the wheels from barrels filled with concrete use a piece of pvc in the center and slide it right over the axle pipe no hub or any thing .Have local wreck company wench it out in the fall.. Think I said to much here and coming up with different ways to do it while I was writing.gxbxcOriginally Posted by gxbxcI am all for the wedge trailer design Saw a bunch of then up at Deep Creek Lake in W. Maryland . Some even had  screen houses  on them. Just buy Axle stubs from Northern Tool or some such place Make then as wide as you want and if you are really cutting cost you don't even need tires on the wheel rims , It is only going to move 40' a year and if you think that the dock will move with the wave action build the wheels from barrels filled with concrete use a piece of pvc in the center and slide it right over the axle pipe no hub or any thing .Have local wreck company wench it out in the fall.. Think I said to much here and coming up with different ways to do it while I was writing.gxbxc
Reply:Originally Posted by sbchp355You can actually by aqua axels designed for docks cheaper than putting a trailer axel or spindle ends on. Most of the more rugged ones I have dseen run a truss type frame. Most of the types are cheaply built and not strong enough. I have had to beef a few up that broke in half either putting them in or pulling them out.
Reply:I don't really have a source. I will try to get a manufacture name. Getting to be the time when everyone will start pulling the docks out. The design would have to be beefef up to work on a large marina scale. I will try for pics in weeks to come.