Basic cement/ ballast Q

[zoothorn]

Ok

45 minutes ago, Onoff said:

You WILL want one in the future. Something like this?

https://www.ebay.co.uk/itm/14-BLACK-PU-WHEELBARROW-WHEEL-PUNCTURE-PROOF-SOLID-3-50-3-00-8-1-bore-UK/323891938308?

 

Yes will note thanks. 30m for an inner.. anyway had to be done/ barrow sorted, & done it. Flippin mess, but no barrows spilt (nearly an OTT full one tho jeepers), some mixes a bit heavy on the ballast, some a bit wet, some a bit ott cement.. but best i could do.

 

What I do have is on my far one (deliberately 1" underfilled to better match level-wise to a full front one) has quite an excess of water on the surface: i can't see anything other than the ballast going to btm & innevitably water 'rises'. Ive mixed pretty well.. but what do I do? front one seems a bit thicker & top level-tapped fairly ok'ish.. but far one I cant cos of the lip.

 

Also what do i do about overnight rain on them? its peeing down right now.

 

 

[Mr Punter]

The water will do it no harm. Concrete cures very well under water.

[Onoff]

As long as the rain isn't that heavy that its washing the concrete out...I'd cover just to be sure.

 

Upturned wheelbarrow over one.

 

Lay two sticks over the other, bit of tarp weighted with a couple of bricks.

[zoothorn]

22 minutes ago, Onoff said:

As long as the rain isn't that heavy that its washing the concrete out...I'd cover just to be sure.

 

Upturned wheelbarrow over one.

 

Lay two sticks over the other, bit of tarp weighted with a couple of bricks.

 

Of course use the barrow.. yes ok good plan. Damn pleased that's done tho- prep took 2x time the job did.. most/ hardest was hauling 2/3rd a ton of ballast just down 4m one bucket a time. Very satisfying the mixer'ing tho, & not too hard once ballast next to: I like the tippy out bit best: I had one foot on like a boss.

[Onoff]

That low plinth...you might want to trim the plastic former level at least so water doesn't sit in there and hasten the rotting of the big timber beam that'll sit there. 

 

How level are these plinths? I reckon a bit of rocking will drive YOU nuts!

 

Might be better just to thin the end of that particular beam down a fraction rather than faff with packing.

 

Can't wait to see the base frame!

[zoothorn]

@Onoff yes I will trim the rear top plinf once its set. How level.. relative to each other you mean? about 1" out still, even having done back one shy 1". So front top one still 1" below back one.

 

Yes I was thinking nip a bit off the beam @ back rather than packing front up: Im already 1 ft higher than I'd thought/ wanted (85cm H between upper & lower plinfs.. but nervous digging back ole in case cliff became unstable/ I think maybe wise I stopped as is tbh.

 

 

[Onoff]

Ref getting things dead level then you could do worse than investing in one of these:

 

https://m.clasohlson.com/uk/Cocraft-HL10-S-Cross-Line-Laser-Level/40-9996

 

Just set up late afternoon/dusk and put a tape measure on each plinth.

 

A fiver delivery unless you can get the order over £35.

 

I used my Cocraft one from here to do my bathroom. 

 

[zoothorn]

3 hours ago, Onoff said:

Ref getting things dead level then you could do worse than investing in one of these:

 

https://m.clasohlson.com/uk/Cocraft-HL10-S-Cross-Line-Laser-Level/40-9996

 

Just set up late afternoon/dusk and put a tape measure on each plinth.

 

A fiver delivery unless you can get the order over £35.

 

I used my Cocraft one from here to do my bathroom. 

 

 

Pretty nifty for £20.. wow I bet these cost £120 a decade ago. I'll consider, but when you say "put a tape measure on each plinth" what do you mean?

 

Tell me about the water rising thing tho- surely the deeper down the more ballast/ stone will settle, so therefore the higher up the more watery it gets: certainly the top layer seems liquid water maybe only 1/2" or so.. but as this is where I'm attatching xyz to.. won't it be the weakest bit this top 1/2"? pro chap gouged a wee channel for this top water to drain off on lower fwd plinf.. I tried to on back top but got in a pickle cutting a 1"  notch to drain off top layer, & heard air wheezing out/ seems I punctured the rib section.. like a nana. I hope to heck I don't find the level's dropped by another 1" tmrw in this back one.

[Onoff]

The laser level is great for the money. My chippy mate saw mine and bought one. Honestly is alright.

 

Easiest way ref a drainage channel would be to have tapped in a bit of 2"x2", 600mm long across the centre of the plinth, at a sloping angle, whilst still wet. Leave in there and pull out when it's going off. BUT...being anal, a square sided channel can get water in and freeze up, expand and crack thd concrete. A bit of round waste pipe would give a dished channel. Not necessary imo here. Too late anyway.

 

However, I wouldn't worry about a drainage channel. Mud, leaves and crud will soon build up around where plinths are. Just once a year clear it off in the Summer and apply liberal coats of Creocote or similar to the wooden ends. You could paint the top of the plinth with black bituminous paint if you wanted. (We lead cap plinths at work - loadsa money! )

 

Concrete will slump a little often. Live with it. (With super heavy loads on crane plinths at work (up to 80 tonnes) we use special disc spring washers on threaded studs in the tops of the plinths that can be loaded along their axis to take up slump). THIS IS STILL A SHED, DON'T SWEAT IT! ?

 

As to the tape thing: Set the laser up with a horizontal beam that spans across all the plinths. Put the end of the tape on the plinth top and pull the tape out vertically. The laser line will intersect the tape. Write down that measurement and repeat for the other plinths. You can work out by simple addition/subtraction the levels relative to one another.

[zoothorn]

3 hours ago, Onoff said:

..Concrete will slump a little often. Live with it. (With super heavy loads on crane plinths at work (up to 80 tonnes) we use special disc spring washers on threaded studs in the tops of the plinths that can be loaded along their axis to take up slump). THIS IS STILL A SHED, DON'T SWEAT IT! ?

 

 

I know I know.. but its a shed on a 45* slope, & its my 1st build effort using concrete which I don't know the way it behaves.

 

How long until set btw? I need to angle-grind off these rebar ends before I impale myself.

 

cheers- zoot.

[Onoff]

5 minutes ago, zoothorn said:

 

I know I know.. but its a shed on a 45* slope, & its my 1st build effort using concrete which I don't know the way it behaves.

 

How long until set btw? I need to angle-grind off these rebar ends before I impale myself.

 

cheers- zoot.

 

I'd leave it a week personally before taking the studs off. Upturned wheel barrow, bucket with a brick on top etc for now.

 

Edit: Or a temporary brick "cairn" is it? Seems apt! ?

Edited September 5, 2019 by Onoff

[zoothorn]

Actually its a log cabin actually.. shed pfft!

 

A week? ah ok- thought it was 24hrs.. just had a peep & looking good! its defo set & no slump down at all on the back one.

 

I sort of assumed the tops would just settle alone level (rebar protrudes proventing a level-tamp across).. is that the idea? can I smooth down any unevenness prior to attatching my plate xyz things with something, or is that too late now too?

[PeterW]

Concrete doesn’t need a week - just whip them off and be done with it. We start building foundation blockwork 48 hours after pouring. 

[Onoff]

Like I say I'd leave it a week. Concrete will be set to walk on etc after 48hrs but reaches about 70% of its strength after 7 days.

[zoothorn]

Ok great chaps- I'll be leaving anyway for a week min/ no rush.. its wales after all. Then onto the beam plan.

 

Cheers zoot

 

 

[zoothorn]

My pro chap outlined a basic plan for the base- wonder what you think:

 

2x full sleeper uprights for lower plinths H ~85cm. A beam(A) to lie flat on the upper 2x plinths (parallel to stream) joining these two. Obvuiously resin-bolted steel bracketed to my plinfs.

 

Then a series of joists across (perpendicular & fixed by alu metal hangers to beam(A), @ 400mm centres (IE celotex between).. to rest upon/ fix to another beam(B) joining the sleeper uprights, & joists continue on over twds the stream by 20% (a common figure in his work for cantilevered overhang/ anyway whatever's max I can go for an added side walky bit).

 

Noggins too?

 

Lastly: 2x added 45* inside brace timbers @ the sleeper pillars > beam above, for added rigidity/ to help prevent racking.

-----------------------------------------------------------------------------------------------------

 

That's his basic suggested plan, kindly & quickly sketched in 5mins after our hard work. Thinking on whatever base I go with, the main thing of concern to me is the wind channels down the gdn & hits my 'shed' front on, hard: like my extention it'll whack the end of, often at 90*. So alot of pressure will be put on my 'lower side', my 2 sleeper uprights will want to domino one another -backwards- I assume.. if say a storm puts wind at max.

 

 

 

[Declan52]

Get yourself 2 of these.

https://www.screwfix.com/p/irwin-quick-grip-12-mini-one-handed-bar-clamp/98247

You can hold the post and then clamp the beam to it. Check your plumb and level and then fix in place. If you need to move the beam up or down it's dead easy to release a bit of pressure from the clamp and adjust to suit.

You will need the diagonal bracing on the upright posts to stop it swaying. 

Definitely put noggins in, it will make a massive difference to the strength of the floor.

Use the correct your of nails for the hangers. 

https://www.screwfix.com/p/easyfix-square-twist-nails-sheradised-3-75-x-30mm-1kg-pack/12788?_requestid=133521

Once it is all fixed in place your relying on its weight keeping it from moving. The diagonal bracing will stop the sway and the fixings into you pads will stop it moving so don't skimp on these.

 

 

[Russell griffiths]

Can you do a sketch from above and one from the side showing height difference, from lower to higher pads, you might not need any hangers, in fact they might stop you gaining height you need. 

[zoothorn]

On 06/09/2019 at 09:14, Declan52 said:

Get yourself 2 of these.

https://www.screwfix.com/p/irwin-quick-grip-12-mini-one-handed-bar-clamp/98247

You can hold the post and then clamp the beam to it. Check your plumb and level and then fix in place. If you need to move the beam up or down it's dead easy to release a bit of pressure from the clamp and adjust to suit.

You will need the diagonal bracing on the upright posts to stop it swaying. 

Definitely put noggins in, it will make a massive difference to the strength of the floor.

Use the correct your of nails for the hangers. 

https://www.screwfix.com/p/easyfix-square-twist-nails-sheradised-3-75-x-30mm-1kg-pack/12788?_requestid=133521

Once it is all fixed in place your relying on its weight keeping it from moving. The diagonal bracing will stop the sway and the fixings into you pads will stop it moving so don't skimp on these.

 

 

 

Great help here Declan.. I like those clamps/ good for general woodwork after too, & those twist nails are interesting: guess would save alot of use of a drill driver plus screws too.

 

One thing I do need to get, & carefully choose, if the right hammer. I need one for these twistys then & use for 4" steel nails I'll use tons of for small walkway projects, plus two later stairs projects too. Ive seen the US carpenters' YTclips with theirs which seem so integral to them/ pg1 important, I think its important to get a quality multi-use one for life.

 

thanks-zoot

[zoothorn]

On 06/09/2019 at 09:31, Russell griffiths said:

Can you do a sketch from above and one from the side showing height difference, from lower to higher pads, you might not need any hangers, in fact they might stop you gaining height you need. 

 

Yup- will photo a sketch later one light better/ post it up. All these joisty xyz & hangers is all new to me.. I'm only relying on vague recalling of a labouring site job 30 yrs ago I last saw these hangers: what I do recall is the Ex+ strength of the joint they made.

[PeterW]

9 minutes ago, zoothorn said:

: guess would save alot of use of a drill driver plus screws too.

 

Screws aren’t certified / strong enough for use in a hanger, has to be galvanized twist nails (or does to meet manufacturers spec..)

 

 

[zoothorn]

9 minutes ago, PeterW said:

 

Screws aren’t certified / strong enough for use in a hanger, has to be galvanized twist nails (or does to meet manufacturers spec..)

 

 

 

Ah- didn't know that. Ok so difference is, a hammer will tonk the joist out of place, a drill won't much: so how do i clamp a perpendicular joist B to beam A so hammering nails won't send B off kilter?

[Declan52]

3 minutes ago, zoothorn said:

 

Ah- didn't know that. Ok so difference is, a hammer will tonk the joist out of place, a drill won't much: so how do i clamp a perpendicular joist B to beam A so hammering nails won't send B off kilter?

The joists will be in hangers so can't move anywhere. The twist nails are for attaching the hangers to beam a , then you drop beam b into the hanger and fix the rest of the twist nails into beam b.

[Onoff]

Some videos here for Simpson Strongtie brand hangers that might assist:

 

https://www.strongtie.co.uk/resources/videos

[Ferdinand]

44 minutes ago, zoothorn said:

 

Ah- didn't know that. Ok so difference is, a hammer will tonk the joist out of place, a drill won't much: so how do i clamp a perpendicular joist B to beam A so hammering nails won't send B off kilter?

 

Usually screws are strong in grip along the shaft ,whilst nails are strong across the shaft.

 

Consider how thinner the core shaft of a screw is compared to how thick it looks - much of the cross section has been taken away for the thread. 

F