Fastners: Best drive type?

[Cheechako]

The only problem with Phillips or Frearson is tools: -using the wrong size, -using worn out driver tips, unless it's something you are going to take in and out many times...

[a64pilot]

Diamond coated bits and all are fancy, but what works even better is spit on the tip and dip it into Ajax or Barkeepers friend or any other abrasive cleanser.

[deblen]

Originally Posted by DeepFrz

In his screwdriver thread, http://www.cruisersforum.com/forums/...rs-184035.html , Dockhead speaks highly of the Pozi screw head. I'm not sure I had ever heard of them before but I am sure I have run into them and Philips screwdrivers don't like them much.

Screw types:https://sizes.com/tools/screw_drive.htm

[peter loveridge]

Robertson are head and shoulders ahead of anything else. I've built 5 boats and always use them. Any industrial supply house in Canada can supply you with thousands if necessary. You can balance a screw at almost any angle, including downwards, on the end of the drill if the bit is reasonably new. However, you need 4 bits , not three, gold, (size<6) green, 6, red, 8-10, black 12 andf above. Now the only reason they are not the world standard is that in the early 1920's, Mr. Ford wanted to use them on his cars, but Mr. Robertson, who held the patent, would happily sell him the screws, but not his company, so Mr. Phillips got the nod. Mr. Robertson's hardware store is still in existence, somewhere in rural Ontario, and is still the company headquarters, though now most of the screws are made in China and they are definitely not all the same quality

[DeepFrz]

Phillips screw heads
drawing of a Phillips head
patent drawing
From Phillips 1936 patent.
The licensor is the American Screw Co. The Phillips system was invented for use in assembling aluminum aircraft, with the object of preventing assemblers from tightening screws so tightly that the aluminum threads strip. The driver will cam out before that happens.

And therein lies the rub.

Great link. Thanks deblen, I've bookmarked it.

[roverhi]

Only touch a screw driver if i'm desparate. Did over 4,000 screws with a screw driver building our Westsail years ago and came down with screw driver arm. Pain in my wrist and and elbow from so many screws that hasn't really gone away after 40 years. Discovered electric screw guns and all was right with the world. The corded ones had plenty of power but the rats nest of tangled cords were a pain. Bought a Milwaukee 12v driver and it was love at first screw. RPM's are controllable so it's easy to start slower and pull the trigger further for more speed when the screw is more stable. Will drive #14 screws and battery charge lasts longer than me. http://www.cpomilwaukee.com/milwauke...efault,pd.html

Also have one of Milwaukee's impact drivers but the RPM is hard to control and often end up over driving and/or stripping out the puka with it. Great tool for removing fasteners but not for driving scews for me.

[ranger58sb]

Originally Posted by peter loveridge

Robertson are head and shoulders ahead of anything else.

Better than Torx? How come?

-Chris

[smj]

I have driven probably hundreds of thousands of screws into household exterior decks over the last 35 years. Started of with Phillips head and then the square drive came along, didn't think it could get any better. Then came the Torx head screws, vastly superior to any other I've used. I'm hoping by the time they come out with a screw head that is better than torx, I'll be retired:-)

[deblen]

Originally Posted by ranger42c

Better than Torx? How come?

-Chris

Torx vs Robertson IMHO:
Too many sizes compared to Robertson's 4 sizes
Difficult to find a good variety of 316 SS Torx wood screws(yet)

I do believe Torx is next best to Robertson

/ Len

[Dave_S]

We have done testing on drivers for screws, we use up to 15,000 in a month. All driven by cordless clutched drivers (battery drills).

I'd rate them in order from good to better.

Slotted
Phillips
Pozidrive
Socket (Allen drive)
Post head socket
Torx
Post head Torx

We now use Phillips for counter sunk screws and Socket for cap screws.

Part of QA is to find over torqued screws - note it, replace it, and correct it. It has been over torqued, change the settings. Pozidrive is better although the screws stay on the driver which should be an advantage except when disassembling.

Buy quality drivers, they should break before they deform. If using a screw driver, buy the longest shaft length that is practical.

[belizesailor]

Originally Posted by Suijin

...

The big issue is like I said tools. I have this nagging concern in the back of my mind that switching will come back to haunt me down the road. Like I'll walk into Bodega Blanca on Santa Cruz in the Galapagos and ask for a Robertson #2 and they are like "Qué?"

....

As posted, "best" all depends on application. If cruising outside of developed countries is part of your plans then fnding anything other than slotted and philips in imperial sizes will be a problem. Anything in good quality SS can also be a problem.

I can just see the next owner of your boat in some remote port...cursing you. [emoji6]

[Cadence]

With SS, I would be more concerned with snapping them off than driver style. It is great for tensile strength but will twist off easily. Drilling it out is a bitch.

[HopCar]

By all means use Robertson drive screws. In this day of internet shopping you should be able to get what ever you need.

Dan thanks for the tip on the diamond coated Phillips bits. I'm going to order some and give them a try.

[Dockhead]

Originally Posted by DeepFrz

In his screwdriver thread, http://www.cruisersforum.com/forums/...rs-184035.html , Dockhead speaks highly of the Pozi screw head. I'm not sure I had ever heard of them before but I am sure I have run into them and Philips screwdrivers don't like them much.

Yes, Pozi is very widespread in the UK, and as far as I know, in the rest of Europe. Don't know about the U.S. An immense improvement over Phillips, which are intentionally rounded -- work of the devil. Basically Phillips the way they should always have been.

Edit: The following article says that Phillips is basically gone in Europe and the Far East, and that Pozi is now the de facto standard. Sounds right to me.

"Pozidriv was jointly patented by the Phillips Screw Company and American Screw Company in the USA. Developed by GKN in the 1960s, the recess is licensed from Trifast PLC in the rest of the world. It is the de facto standard in Europe and most of the Far East, where Phillips is almost nonexistent. The proper Pozidriv screws have a flatter bottom to the socket, and steeper sides, so the driver doesn't cam out as easily. The name is thought to be an abbreviation of positive drive.

"Pozidriv is similar in appearance to the classic Phillips crosshead, but in fact is substantially different. On close examination you will notice a second set of cross-blades at the root of the large cross-blades. These added blades are for identification and match the additional makings on the head of Pozidriv screws, known as "tick" marks, single lines at 45 degrees to the cross recess. So, the marks are for identification purpose. Pozidriv also does not have the rounded corners that the Phillips screw drive has. The tip or the driver is blunt which also helps it to seat better into the recess in the screw, unlike the Phillips which comes to a sharper point.

"Identified in ANSI standards as type IA. Pozidriv drivers will not turn Phillips screws; but Posidriv screws can be turned by Phillips screwdrivers, although they should not be used as they tend to ride out of the recess and round the corners of both the tool and screw recess.

"Advantages and Disadvantages of Pozidriv

"The largest advantage it offers is that, when used with the correct tooling in good condition, it does not cam out, allowing great torque to be applied. The chief disadvantage of Pozidriv screws is that they are visually quite similar to Phillips, thus many people are unaware of the difference or do not own the correct drivers for them, and use incorrect screwdrivers. This results in difficulty in unscrewing the screw and in damage to the slot, rendering any subsequent use of a correct screwdriver unsatisfactory."

Learn something every day.

When a Phillips Is Not a Phillips!: 30 Steps (with Pictures)


https://bsfixings.uk/the-difference-...and-pozi-screw

been.https://mechanics.stackexchange.com/...-phillips-head

[Dave_S]

Originally Posted by Cadence

With SS, I would be more concerned with snapping them off than driver style. It is great for tensile strength but will twist off easily. Drilling it out is a bitch.

Some of the cheap counter sunk screws are formed with the head not central to the shaft of the screw (believe it or not) and these often snap the heads off before they reach full torque and as you say that's not good ! The head size often varies as well which can cause the outer rim of the screw head landing before the tapper of the head seats which can also cause the screw to fail.