Imperial wood screws

[DiyNutJob]

I am looking for 4.2mm x 25mm pozi csk twinthread wood screws in yellow zinc. I can find it in BZP and stainless steel. Anyone knows where I can buy the yellow one? The internet says yellow has greater corrosion resistance than silver. SS would cause galvanic corrosion on zinc. I am replacing some old screws and need an exact fit of imperial size 8. Thanks.

 

[blup]

Will the 0.2 mm difference between a 4mm screw and a no. 8 be noticeable? Ive never come across yellow passivated screws in imperial sizes. Only self colour or grey. Is brass an option?

 

[DiyNutJob]

M4 metric is a lot less than 4mm. M4.5 is 4.3mm but head too big. The internet says metric took over in the 90's. Wasn't there yellow zinc before that for all the imperial screws used? I have no idea and wasn't into wood screws then.

 

[big-all]

i use screwfix turbogold and axminster woodspur have been using them for years to repair fence and fence panels and perhaps 7- 10 years on when i remove the very black screws they are fully fine and i recycle and reuse as less obvious than new screws
now i am not saying there is no corrosion as they have changed colour but would guess sub 5%
there is the odd screw thats a bit worse but not many and none have failed

 

[DiyNutJob]

I wouldn't worry about for fencing. My application is ZYP (possibly electro-brass ?) hinges.

I found a possible candidate: https://shop4fasteners.co.uk/catalo...ood-screws-electro-brass-8-x-1/category/4019/

But, WTF is electro-brass? How do I tell if the old screws are electro brass or ZYP?

 

[opps]

Fasteners, Fixings, Screws, Nuts & Bolts - Serving London & the UK

www.orbitalfasteners.co.uk

I don't know if they have the ones you want, I don't have the time, or inclination to check, but they will sell individual screws. Min of £25 plus vat for delivery. I have used them a few times and, within the m25, I get next day delivery.

 

[DiyNutJob]

Would you say the hinge and the nearest screw are electro-brass? The outer screws are ZYP, more yellowy and less greeny.

The middle m4.5 screw could work but it's single thread. I am unable to find a twin thread m4.5.

 

[DiyNutJob]

I don't have the time, or inclination to check, but they will sell individual screws.

You always have time for posting, and conducting cabal business, but no time to come up with good info. But, never mind. I ordered electro brass and took one in the gut for £12, and it's probably slow delivery.

I am sold on the hint of purple on the product image. This is present on the hinge.

 

[foxhole]

They are hinges with holes, they are screws , they all fit .

 

[Harry Bloomfield]

But, WTF is electro-brass? How do I tell if the old screws are electro brass or ZYP?

Steel, electroplated with brass? They will stick to a magnet.

 

[DiyNutJob]

They will stick to a magnet.

How does that help if steel is under both brass plating and ZYP?

 

[Harry Bloomfield]

How does that help if steel is under both brass plating and ZYP?

It will help you to identify steel, which is brass plated - which was the question you asked.

 

[DiyNutJob]

It will help you to identify steel, which is brass plated - which was the question you asked.

It helps me identify steel. The identification required is to tell which is brass plated and which is ZYP.

 

[Why Not Indeed]

As "ordinary" galvanising has a mottled finish then my guess is that the yellow mottling is zinc plating and a plain yellow finish is electro-brass plating.

 

[Harry Bloomfield]

Identifying Platings

Any help?