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PVC pipe for pontoons?

Johnny		Posted : Friday, 24 January 2014 9:17:57 AM(UTC)
Rank: Gold Flake Groups: Registered Joined: 2/12/2013(UTC) Posts: 17 Location: Southland Thanks: 1 times		im thinking of making pontoons from 300mm pvc pipe because i think they will be lightweight and easy to slide over the shallows, up the bank and onto the trailer. has anyone had any experience using these? some pro's and con's about them would be appreciated. here is a link to a short video of my dredge in action with the motor etc that was on it before i got it. http://www.youtube.com/watch?v=iD0bUIzb9r4 its approx 2500mm long and 1500mm wide

LBD		Posted : Friday, 24 January 2014 3:26:25 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/06/2012(UTC) Posts: 101 Location: PhuBia...for a change Thanks: 22 times Was thanked: 43 time(s) in 33 post(s)		2 x 2.5m pontoons.... as long as the whole thing loaded with the sluice box full weighs less than 353KG... You may want to consider using reducers at one end instead of flat ends to give somewhat of a bow to assist over rocks Otherwise I se no problems

nafcd		Posted : Friday, 24 January 2014 9:45:28 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 28/12/2012(UTC) Posts: 276 Location: ashburton Thanks: 8 times Was thanked: 46 time(s) in 34 post(s)		cost would be the only problem I could see. larger size pvc is pretty expensive. 6m length brought in for work was high pressure but cost around $500 and reducers etc aren't cheap

Johnny		Posted : Friday, 24 January 2014 10:45:30 PM(UTC)
Rank: Gold Flake Groups: Registered Joined: 2/12/2013(UTC) Posts: 17 Location: Southland Thanks: 1 times		cheers for the replies. i am only just guessing but i think the total weight sitting idle will be around 180kg with the current steel frame and the PVC, less when i get the alloy frame made. i dont mind the idea of adding extra bouyancy if needed while the dredge is full of water and rocks. the pontoons in the video are around 60kg each after sitting on the trailer for a few days but, they have reached a well earned retirement age and get heavy while in the water. it took me 4 hours of hard slogging and winching to get 200 meters upstream and onto the trailer. and weighing in at 70kg myself, i need to go with the lightest and least resistance to the current and dragging over rocks possible while still being cost efficient. i can get a 5 metre length of 300mm for $290 from a contractor who has 3 left over from a job. at mico they want over $500 retail. instead of buying reducers etc, i was thinking of making a wooden plug to glue inside both ends and trying make a cone shape to fit on the front from some polystyrene and fibreglass i have lying around. Edited by user Friday, 24 January 2014 10:49:25 PM(UTC) \| Reason: Not specified

LBD		Posted : Friday, 24 January 2014 11:03:18 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/06/2012(UTC) Posts: 101 Location: PhuBia...for a change Thanks: 22 times Was thanked: 43 time(s) in 33 post(s)		4 hours.. 200 meters... must be a rugged bit of river....

oroplata		Posted : Saturday, 25 January 2014 12:53:04 AM(UTC)
Rank: Gold Ingot Groups: Registered, Moderators Joined: 16/06/2011(UTC) Posts: 1,040 Location: Christchurch Thanks: 23 times Was thanked: 211 time(s) in 152 post(s)		PVC pipe tends to shatter if dropped hard enough and then the party's over. It also degrades in sunlight. I would look at HDPE pipe instead (the black stuff). Pretty sure that has a bit more give in it. Or maybe that's no good because it's softer and would get scraped away faster being dragged over rocks? Or you could make one pontoon out of PVC and the other out of HDPE and then report back later. :^)
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Johnny		Posted : Saturday, 25 January 2014 11:29:30 AM(UTC)
Rank: Gold Flake Groups: Registered Joined: 2/12/2013(UTC) Posts: 17 Location: Southland Thanks: 1 times		Originally Posted by: oroplata PVC pipe tends to shatter if dropped hard enough and then the party's over. It also degrades in sunlight. yes, i have thought of that. it will need covered when not being used and a cushion for on the trailer. the stretch of creek i had to drag the dredge up was mostly shallow, had 3 sets of rapids and some crazy currents. i was tying ropes to trees to stop it floating away if i slipped or lost my hold on it. in hindsight i should of removed the motor to lessen the weight but i wanted to bring it upstream as a whole unit minus the hose and power-jet to prove to myself i could do it. i had an electric winch off a hilux and 2 car batteries with me but the first battery (a small one out of my bosses forklift) went flat going over the first rapid so i really tried not to use the winch until i had no choice as i needed it to pull the machine up onto the river bank and onto the trailer. it was an adventure :) and that is exactly the same spot i am going to when i next head back haha. but with pvc pontoons instead of leaking old floats made from insulated panels i should be able to drag the dredge up at least 1 of the rapids without using a winch and be able to maneuver around the rocks in the shallows alot easier and get the dredge upstream in quarter of the time. and if i am really lucky, somebody might be around to help, then i wont need the winch or ropes. i think a 15 minute haul to the trailer would be possible then.

nafcd		Posted : Saturday, 25 January 2014 1:15:43 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 28/12/2012(UTC) Posts: 276 Location: ashburton Thanks: 8 times Was thanked: 46 time(s) in 34 post(s)		the black pipe in 300mm would be bloody heavy and its hard to find a glue to stick to it if you are planning to make your own end caps.

LBD		Posted : Saturday, 25 January 2014 4:21:23 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/06/2012(UTC) Posts: 101 Location: PhuBia...for a change Thanks: 22 times Was thanked: 43 time(s) in 33 post(s)		http://www.indac.co.nz/I...20Retail%20Catalogue.pdf maybe you should have a chat to these guys and get a price for 4 x gold dredge floats...?

cariboo		Posted : Saturday, 25 January 2014 4:31:34 PM(UTC)
Rank: Gold Flake Groups: Registered Joined: 18/10/2013(UTC) Posts: 11 Location: coast Thanks: 2 times Was thanked: 2 time(s) in 2 post(s)		I am in the process of building a 3in dredge and have looked at many options for pontoons and have decided too go with aluminium mainly because it won't wear out dragging over rocks etc. (with runners on bottom of pontoon) if you go too your local sheetmetal shop they can fold and weld for a lot cheaper than pvc pipe will cost will put up some pics when/if camera drys out after having a swim...with me
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Johnny		Posted : Saturday, 25 January 2014 6:10:19 PM(UTC)
Rank: Gold Flake Groups: Registered Joined: 2/12/2013(UTC) Posts: 17 Location: Southland Thanks: 1 times		aluminium would sure be sweet but i thought it would be expensive. i will go into stabicraft and a couple of other sheetmetal outfits around town on monday and get some quotes

LBD		Posted : Saturday, 25 January 2014 6:39:52 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/06/2012(UTC) Posts: 101 Location: PhuBia...for a change Thanks: 22 times Was thanked: 43 time(s) in 33 post(s)		Sheetmetalcraft in Ingill are pretty good too... Fold up a 1.2 x 2.4 sheet into 300 x 300 x 2400 ... that would be sweet and give you 430kg bouyancy. You may want to attach nylon runners to help it slide over rocks one day

jafa		Posted : Saturday, 25 January 2014 6:53:33 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 22/11/2011(UTC) Posts: 134 Location: auckland Thanks: 22 times Was thanked: 23 time(s) in 19 post(s)		I had a mate build a 4'' using some round pvc for floats and the buoyancy was no good something to do with it being round once it got past the half way mark it just sank!. id go alloy or those indac pontoons 4 would more than do it they are $250 each and they last for decades.
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LBD		Posted : Saturday, 25 January 2014 7:19:18 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/06/2012(UTC) Posts: 101 Location: PhuBia...for a change Thanks: 22 times Was thanked: 43 time(s) in 33 post(s)		Jaffa is correct about round floats, as the depth the float sinks in the water past the 1/2 way mark, the reserve bouyancy reduces fast... but if your 180kg calculation is correct (With water and gravel in the sluice) then the 350 kg bouyancy earlier mentioned will be fine. But again, those idac floats are a great way to go... Or get 2 or 3 sheets of 6mm exterior ply, some epoxy glue, resin and cloth....then attach a few sheets of 6mm plastic to protect the underside from rocks... and help it slide Edited by user Saturday, 25 January 2014 7:32:28 PM(UTC) \| Reason: Not specified

cariboo		Posted : Saturday, 25 January 2014 8:03:20 PM(UTC)
Rank: Gold Flake Groups: Registered Joined: 18/10/2013(UTC) Posts: 11 Location: coast Thanks: 2 times Was thanked: 2 time(s) in 2 post(s)		pontoon size..10 inchx8inchx48inch for 3inch dredge with table being 12x48(roughly) pump and motor 25 kg plus 20 kg of hose etc....ally sheet $80 fold/weld etc $40 this size pontoons would be more than enough an extra $30 or so will get you some 10mmx25 flat ally to weld on bottom as runners
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Johnny		Posted : Saturday, 25 January 2014 9:19:14 PM(UTC)
Rank: Gold Flake Groups: Registered Joined: 2/12/2013(UTC) Posts: 17 Location: Southland Thanks: 1 times		all of these replies with options, experiences and opinions about different materials, shapes, etc are awesome. just what i was hoping for. btw, my dredge is a 5 inch using a powerjet and 4 metres of suction hose

LBD		Posted : Saturday, 25 January 2014 9:58:02 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/06/2012(UTC) Posts: 101 Location: PhuBia...for a change Thanks: 22 times Was thanked: 43 time(s) in 33 post(s)		Originally Posted by: Johnny btw, my dredge is a 5 inch using a powerjet and 4 metres of suction hose The Idac floats will be too big then at a guess... Typical 5 inch single engine keene is 180kg (plus water and gravel) The floats on a 5 inch keene are similar to the Idac float but smaller... I am not handy to my dredge at the moment but from memory they are about 430 wide 370 high and 1200 long and there are 4.

zimbo		Posted : Sunday, 26 January 2014 4:45:11 PM(UTC)
Rank: Gold Nugget Groups: Registered Joined: 22/03/2011(UTC) Posts: 72 Thanks: 5 times Was thanked: 29 time(s) in 18 post(s)		here are the pontoons i made for my dredge 20L oil drums, which can be found at you local auto workshop or refuse station, the measure 2000x300x400 and if you get a hole in one simply replace it. the frame i made from 25x25 gav tubing and seems to be strong enough. another good ideal is heavy duty lay-flat hose. zimbo attached the following image(s):

nafcd		Posted : Sunday, 26 January 2014 7:56:41 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 28/12/2012(UTC) Posts: 276 Location: ashburton Thanks: 8 times Was thanked: 46 time(s) in 34 post(s)		the 20L drums looks a neat, simple and cheap way of doing it. well done there

Johnny		Posted : Sunday, 23 February 2014 9:11:15 AM(UTC)
Rank: Gold Flake Groups: Registered Joined: 2/12/2013(UTC) Posts: 17 Location: Southland Thanks: 1 times		cheers zimbo, i found a place in temuka with loads of 20 Ltr containers for 50 cents each. i drive a truck between invers and chch so they were easy to bring home. here is a video of the dredge with the 20's as floats. http://www.youtube.com/watch?v=UYEdWJBUSA4 i will bring the dredge home one day soon and redo the floats but they are working great. i can even stand on the dredge to re-fuel :) btw zimbo, i bought the motor/compressor off you through trademe lol. if i seen your post earlier we couldve saved you some trademe fee's. (im blaming the nice weather we have had, no time to be on the puter with work and play outside) Edited by user Sunday, 23 February 2014 9:12:25 AM(UTC) \| Reason: Not specified

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