Special washer for flat head screws?

[yarden]

Hey guys,
I own a DIY electric skateboard with a custom deck that I created my own.

now the board uses the following types of screws:

(sorry for the dirt)

its a flat head screws where the head part is on top (where you stand), and on the bottom the screws are tightened with a nut


these are the screws I'm using:

a 1" long and 0.18" diameter with flat (triangle shape) head, and nut to close it


Now, my wood is pretty soft so if I tighten it too hard (easiliy with hand) the screw goes inside the wood and enlarge the whole.
Its realy delecated, especially with electric driller, like that:

I must be super gentle to watch when its about as flat as the surface, maybe a bit more inside, and stop tightening, otherwise I tear up the wood.
And thats not a great solution for skateboard with vibration problems and stuffs like that.

so my question is:
Is there sort of special washer for such screws to avoid that problem?
obviously not a basic washer, cuz that will leave the head above the surface,
maybe some triangled shaped washer or something that will protect the wood? and maybe also allow me to tighten it hard with no worries?

any name for such thing or link will be helpful
thanks!

 

[Stanley services]

you can buy countersunk washers of the relevant size to solve the problem. Just search for these on a search engine

 

[etaf]

maybe some coachbolts , and also some nylon lock nuts , which will stop coming loose with vibration
Not sure of suppliers in your country so a search maybe required, BUT they are easily available in UK , so no reason why they wont be available in your contry

Coachbolts

coach bolts flat head - Google Search

www.google.com

Nylon lock nuts

nylon lock nuts - Google Search

www.google.com