Why are these 2 types of screws different prices? (Both Screwfix Packs are 1000 Pcs /Gold VS SIlver?

Danny_G

Why are the prices of these screws different, there is a £5 difference between them, their quantity is the same, I know one is silver and one is gold,  but why is the Silver one more expensive by £5?

Is there something in one that the others don't have?

(We just want them to make an outdoor shed,  and we will be doing it at a slow pace so if it rains, the rain water might touch the water, but will try to minimize that.  so which would be  best out of the 2 for the outdoor shed?)


Quicksilver

QUICKSILVER PZ DOUBLE-COUNTERSUNK WOODSCREWS TRADE CASE GRAB PACK 1000 PCS
(32001)
Price is £14.99
https://www.screwfix.com/p/quicksilver-pz-double-countersunk-woodscrews-trade-case-grab-pack-1000-pcs/32001


Goldscrew

GOLDSCREW PZ DOUBLE-COUNTERSUNK WOODSCREWS TRADE CASE GRAB PACK 1000 PCS
(99867)

£9.99INC

https://www.screwfix.com/p/goldscrew-pz-double-countersunk-woodscrews-trade-case-grab-pack-1000-pcs/99867

Also, Are both rust free, it water touches them?

Cheers

FreeBear

The silver are a twin thread screw, the gold a single. Twin threads have a steeper helix angle and require fewer turns to drive it in the same distance. Doesn't explain the ~50% price difference though...

neilmcl

I've always used the cheaper Goldscrew packs, not had any issues with them.

Rodders53

https://www.screwfix.com/c/screws-nails-fixings/screws-trade-packs/cat10070001#category=cat10070001&sort_by=price

For the same single thread vs twin thread both Silver and Gold are the same price.  (£9.99 single vs £14.99 twin thread).  Twin thread may be quicker less effort if hand-driving the screws rather than using a power tool?

Neither are especially rust resistant - both are plated/passivated ordinary carbon steel. 
So it's a matter of colour preference.  The silvers I've used outside have survived quite well considering.  Stainless steel would be required if you wanted proper rust resistance but would be overkill / too expensive for a garden shed.

Most sheds are assembled with plain steel nails, or occasionally galvanised nails as used in fencing.

It may be worth pricing up boxes of the screw sizes you will actually use rather than a random selection from those trade packs... which are likely to run out of the ones you need quite quickly?

sevenhills

Rodders53 said:
 Twin thread may be quicker less effort if hand-driving the screws rather than using a power tool?

Surely if they are quicker to screw in, more force from the screwdriver will be required?

Danny_G

Single thread  vs twin thread,  single takes more effort to screw in?

I will be using an cordless drill on them, so a question is would I notice the difference if I use the single thread?

Rodders53

Danny_G said:

I will be using an cordless drill on them, so a question is would I notice the difference if I use the single thread?

Yes.  The twins would take slightly less time to screw in than the singles. But all the other bits of the build process time taken would be the same.

sevenhills said:
Surely if they are quicker to screw in, more force from the screwdriver will be required?

I used 'effort' as in "strenuous physical exertion" because it takes almost twice as long to drive home the singles. 
Likely clearance and pilot holes would be needed drilling before using either a manual or power screwdriver to avoid shearing some larger/longer screws. 
The actual turning force (torque) may not be too dissimilar (in my occasional experience of using a mix of both types of thread over the years), although I'd agree that you'd expect the twin to need more?

GDB2222

Ordinary steel screws will rust. It’s not the screws that will look unsightly, but the rust will be washed down the wood by the rain, leaving quite large stains. If you’re happy with that look, fine, otherwise use stainless screws even though they are more expensive- around £10 for 200 in the sort of size you will need.