Self Tapping Screws -Suggestions

[Neville B]

Hello
Just started to fix my hard brake lines to the chassis running from front to back, I thought I would use these Stainless Steel self tappers but I have had two where the thread has gone either installing or removing and when thread goes they are very difficult to remove

I've tried a slightly bigger drill but then they are too loose

They just dont seem very strong

I can't go much bigger as these are going in a double pipe clip in the centre

Is Stainless just to soft?

Any suggestions please for UK Type and Source?

Thank you

 

[DJ]

I ended up using only screws with a hex head,star drive or allen head.They drive easily with an electric drill.I have had some in and out several times. No problem.

 

[DaveC]

Are you trying to avoid using rivets? Should be a permanent installation, worst case you drill the rivet out if you need to remove it.

 

[Bob Stoeger]

Riv nuts !! The only way to go . Reusable strong and easy to install you can get a whole kit from Amazon!!

 

[Neville B]

Re Rivets I hadn't thought of that, worth considering but if you do need to drill out then it will leave the back part in the chassis rail
Re Riv nuts yes could be an option
Thanks for the replies

 

[JP Verweij]

Forget philips star
Torx or allen screws are the way to go.
My brake lines are also clamped with screws and P clamps

 

[Randy V]

My dad taught me years ago -
If the hole is too large for the screw, glue a toothpick into the hole and try again (obviously wood).
For metal - I have many times used a small bit of copper wire in the hole with the tail sticking out and then installing the screw. I did it just yesterday. Cut off excess tail with a nippers..

 

[Neil]

If you're worried about the small end of a drilled-out rivet remaining inside your chassis rail, what about the shavings produced by drilling a larger hole for a Riv-Nut? Use an aluminum rivet in an aluminum chassis rail and then smear some clear silicone RTV over the rivet head to seal it against moisture wicking in.

 

[JimmyMac]

If you must go the route without riv-nuts look at quality self-drilling screws for light steel by makers such as Ejots and not cheap SS self tapping screws.
There is a difference, but whichever you choose go for "truss" heads which provide more strength.

 

[DaveC]

if you do need to drill out then it will leave the back part in the chassis rail

Take a poll of everyone on here with completed cars, and I don't think 1% will attest to having zero rivet parts in one of their chassis tubes.

 

[PhillipM]

I mean, they're more just wood screws, you want some proper light metal/tek screws.

 

[Dwight]

those are wood screws.
you need to buy metal self tapping screws. Something like this one.

https://cdn.shopify.com/s/files/1/0277/8644/4936/products/Self-Drilling-Phillips-Truss-Wafer-Black-Zinc.01_7738d38a-9e4a-452c-91a3-69a100122c89_1000x1000.jpg?v=1594750184

 

[Neville B]

Ok I get it now, I hadn't realised they were wood screws, thanks for all the replies

 

[JimmyMac]

those are wood screws.
you need to buy metal self tapping screws. Something like this one.

https://cdn.shopify.com/s/files/1/0277/8644/4936/products/Self-Drilling-Phillips-Truss-Wafer-Black-Zinc.01_7738d38a-9e4a-452c-91a3-69a100122c89_1000x1000.jpg?v=1594750184

Exactly and 1/2" in length should be enough.

 

[Terry Oxandale]

My thoughts. The self-drilling screws work okay. IMHO, the hole that is drilled with these is slightly too large to promote a tight enough thread to allow good torque with the fastener in thin sheet (or aluminum sheet). The original self-tapping screws on the first post, work great, IF the right pilot hole size is drilled. So, I like the originally posted screws for thin-gauge sheet metal, and the self drilling for thick-gauge sheet, or steel tubing. With that said, SS fasteners nearly always gall in the original post, whereas a good plain steel screw usually survives the thread creation process.

This has always been helpful for me:
=CRAFTSMAN= TOOLS WF GIMLET SCREW STARTER TOOL # 41026 MADE IN USA RARE! | eBay

 

[Ed McClements]

Hello
Just started to fix my hard brake lines to the chassis running from front to back, I thought I would use these Stainless Steel self tappers....

How often are you thinking of removing and re-installing the hard lines? If they're staying in place for the next ten years, save yourself the aggro of self-tappers and just use sealed-end pop rivets. Should you ever need to drill them out, I'm sure you could squirt some box-section anti-rust treatment into the chassis rails, which should gum up the loose ends and prevent them from rattling...!

 

[Neville B]

Wow wasn't expecting so many replies
These are the clips I am using just inside the cabin, I think I struggle getting a pop rivet through them so I'm going to try self drillers designed for metal outside I might use stainless steel Pclips for the single pipe runs I'll probably pop rivet those

Thank you for all the replies

 

[Neil]

OK....