Posidrive Camming out

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RossJarvis

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Is it me or is there another reason why posidrive screws seem to "cam out" more often these days. I seem to feel that posidrive screws seemed to be more tolerant of the driver being "off-square" in the past whereas these days they chew up a lot more often. I'm talking about using power tools to drive them in. Or is it because all my drivers have gazillion more torques than they used to? Plus I seem to get more snapped screws than I used to. Or is it because I mainly use a well known brand's Screws wot are Gold coloured which are Fixed?
 
I'm always using (well nearly) that brand and haven't been having any problems with either impact or drill driver. Sunk a box of 5x50 in ply and joist last week with no troubles.

Are you using hardwoods more?
Have you changed your driver bit brand recently?
Are you being tight and using the same driver bits for weeks on end :D
 
Simple answer is to use Torx screws. Apart from a few packs of pozidriv all my screws are Torx and unless I'm holding the drill right off to one side they never cam out, or allow the bit to jump out the screw completely and drill into fingers at 2300 rpm...

There's a Toolstation close to me so I tend buy their Torx Fast range most of the time and for the price the quality isn't bad at all. They even come with a free bit.

If you're set on a Pozidriv screw then Screw-Tite make pretty decent fixings.

Mark
 
No skills":33qr8wkd said:
I'm always using (well nearly) that brand and haven't been having any problems with either impact or drill driver. Sunk a box of 5x50 in ply and joist last week with no troubles.

Are you using hardwoods more?
Have you changed your driver bit brand recently?
Are you being tight and using the same driver bits for weeks on end :D

Not noticeable in hardwoods which I always pilot drill. I generally renew bits frequently, maybe I need to be more frequent! I've had similar issues with DeWalt, Irwin, Wera and Makita bits (although the Makita super-duper gold are the worst).

The thing is, if I get the driver dead in line with the screw there's usually no problem, but if I go more than a degree or two off there's loads of problem. So it's much more noticeable when access is a bit iffy. Torx head screws like Mark says give no issues.
 
Makita the worst? I'm shocked.. :roll:

You have me wondering now, a good pozi drive screw would push on a screw bit and stay there if you held the drill horizontal (allowing for not waiving the drill around or using big screws).

The impact rated bits have never been as good a fit in pozi/Philips screws as good quality standard bits imo

I'll go see what driver bits I've got laying around and see how they fit some screws...
 
As Mark A says torx screws are brilliant, I've only recently started to use torx head screws and find that the torx fitting is excellent, with the pozidrive bits I had to change the bit quite frequently even using premium bits they seemed to ware and start to cam out, I highly recommend Spax screws, I've been using them for over 10 years now and have had no issues with them at all.
I rarely use a impact driver, mainly use a 12v Milwaukee compact driver, piloted and countersunk whenever possible
HD
 
Hmm, quick test with 5x50 screws and millwaukee/erbauer impact bits and a fessy standard bit - screws sit on the bits ok on the horizontal but any wiggling and their falling off.

I think I don't get much cam out though just being used to using less forgiving screws, at work we use loads of Philips 2 screws - drywalls (for anything that's not into steel or important) and self drilling screws in varying size into steel - any offline driving with them and their knackered.

I will withdraw any further musings with that in mind.
 
I'm now using top-end 18v Makita and a Festool 18v driver so maybe it's more noticeable due to the additional power in the tools, my last Makita driver didn't seem to have quite the same issues, so maybe the power is exceeding the posi/Philips head. The torx head is much better but I'm not aware of the same range of fixings, e.g 3.5 x30 - 6x100 inclusive. I'd have thought torx wouldn't suit smaller sizes.

I've also noted a many items which come from the far-east with Philips heads which don't seem to be punched deep enough for any driver to work properly, but maybe I'm just becoming paranoid!!!!
 
Tis possible that new drivers are too much for pozi screws heads. But again it wasn't much of a problem last week and we were using a T18 and a milwaukee brushless so torque isn't lacking..

I think tiny torx or similar must be available. I have an oak floor to put on top of this ply subfloor and I will be using tounge tite screws which are around 3.5mm and have the most tiny torxish head I've ever seen.

Fwiw imo blah blah etc
 
I'm not sure if most people realise but pozidrive screws were designed to cam out in the days when screws were inserted by machines that didn't have a clutch. The absolute best in my opinion are Robertson screws. Once you've tried them anything else is rubbish.

https://www.squarescrews.co.uk

I first saw them when I went to Canada about 15 years ago, they're popular in the US as well.
As far as I can tell the only reason they didn't replace rubbish like Philips and Pozidrive was due to licensing fees and latterly just the habit of folks accepting second best.

Not a very good picture but you get the idea.

ec51b95fbfb3ee8cc71e847e9e1b29e3_zpsdyg9xtjp.jpg


Forgot to add, don't try Makita brand square drive bits, they simply don't fit! I told Makita and even sent the bits back with a selection of screws but they didn't even bother to reply. Luckily they are the only brand I've tried that don't fit square drive screws.
 
woodpig":2mq00or5 said:
I'm not sure if most people realise but pozidrive screws were designed to cam out in the days when screws were inserted by machines that didn't have a clutch. The absolute best in my opinion are Robertson screws. Once you've tried them anything else is rubbish.

https://www.squarescrews.co.uk

I first saw them when I went to Canada about 15 years ago, they're popular in the US as well.
As far as I can tell the only reason they didn't replace rubbish like Philips and Pozidrive was due to licensing fees and latterly just the habit of folks accepting second best.

Not a very good picture but you get the idea.

ec51b95fbfb3ee8cc71e847e9e1b29e3_zpsdyg9xtjp.jpg


Forgot to add, don't try Makita brand square drive bits, they simply don't fit! I told Makita and even sent the bits back with a selection of screws but they didn't even bother to reply. Luckily they are the only brand I've tried that don't fit square drive screws.

Can you give a source for this?I have seen it stated quite often that this is indeed the case for Philips heads,but never pozidriv.If I really had to depend on a screw head not camming out,I would use Torx.
 
It's discussed in the link above. Henry Ford was a great fan of the concept apparently but didn't want to pay the licensing fee.

You can place a Robertson screw on the tip of the driver and it won't drop off, no magnets required. Handy for brass or stainless screws.
 
Philips is, Pozi isn't.

I don't have a problem at all with Pozi for boshing things under 150mm in. Impact drivers might be noisy but get rid of cam out. Torx is nicer for looks and precision, but I find Pozi more self-locating and easier to spin things in quickly, that may just be me though. Torx or hex better on really big things obviously. I like stainless torx for looks.
 
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