PINTO CAR CLUB of AMERICA

Welcome to FordPinto.com, The home of the PCCA => General Help- Ask the Experts... => Topic started by: 76hotrodpinto on November 13, 2014, 12:01:39 PM

Title: Door hinge pin diameter?
Post by: 76hotrodpinto on November 13, 2014, 12:01:39 PM
I'm thinking I'll fab up some titanium door pins today, to replace the ones in my 76. In the interest of not having to have a door off the whole time I'm machining them, does anyone know what the original diameter was? Then I can turn them out and just have to have things apart long enough to replace them. Thanks.
Title: Re: Door hinge pin diameter?
Post by: dick1172762 on November 14, 2014, 02:00:02 PM
For lite weight door pins? Or for???? Why? What are we missing?
Title: Re: Door hinge pin diameter?
Post by: 76hotrodpinto on November 14, 2014, 10:10:35 PM
It's all the rage with the kids! Naw, I just have a bunch of ti round stock, and happen to need new door hinge pins.
Title: Re: Door hinge pin diameter?
Post by: amc49 on November 15, 2014, 03:31:40 PM
Your call of course but the titanium usually used there is not known for having great shear strength, door pins ARE sort of a safety issue as they are one half of the door holding force if you get t-boned in an accident. Far less risky places to use it all over the cars.
Title: Re: Door hinge pin diameter?
Post by: 76hotrodpinto on November 15, 2014, 04:30:38 PM
We use only industrial grade 1 ti. And it's far more resistant to shearing than even hardened steel. We don't even attempt to sheer ti, it will distort the shear blade. We make heavy machinery pivot pins out of it, just for that reason.
Title: Re: Door hinge pin diameter?
Post by: amc49 on November 15, 2014, 09:46:30 PM
My bad, I was curious before and went looking around and found Ti-6Al-4V and it said that at the Aerospace Metals website. Went back and rechecked, it is only grade 5, curious, they said it was the most commonly used industrial alloy of titanium.

How does one make pivot pins and them work if the metal commonly seizes up when run directly against steel? That was supposed to be one of the bugaboos of titanium rods, that they must have upper end pin bushings as they would not wear directly against steel at all.
Title: Re: Door hinge pin diameter?
Post by: dick1172762 on November 15, 2014, 10:37:24 PM
 

   That's what I've been told in my 63 years of aerospace employment. The same old story of dissimilar metal.
Title: Re: Door hinge pin diameter?
Post by: 76hotrodpinto on November 16, 2014, 12:14:02 AM
My bad, I was curious before and went looking around and found Ti-6Al-4V and it said that at the Aerospace Metals website. Went back and rechecked, it is only grade 5, curious, they said it was the most commonly used industrial alloy of titanium.

How does one make pivot pins and them work if the metal commonly seizes up when run directly against steel? That was supposed to be one of the bugaboos of titanium rods, that they must have upper end pin bushings as they would not wear directly against steel at all.

I would assume some sort of lube, but I couldn't say for sure. I make them and ship them, I don't install or use them. I've used it in many oddball projects though, and against a few different metals, with no seizure ever. But I hardly do anything aerospace related. Just custom car stuff and tools and such.
Title: Re: Door hinge pin diameter?
Post by: amc49 on November 16, 2014, 08:41:44 PM
I've been told more than once you absolutely cannot run a steel piston pin in a bare titanium rod pin bore, even with plenty oiling they will seize to rip rod up. From more than one major engine builder. Maybe your pins are used in steel parts with bushings of some sort.
Title: Re: Door hinge pin diameter?
Post by: 76hotrodpinto on November 16, 2014, 08:51:34 PM
No no no. Not for motors or anything like that. They put them on bucket loader arms and tractor movements. That must be why I was wondering what the hell you guys were talking about. Basically huge hinge pins with grease journals bored into them. Not rod pins.
Title: Re: Door hinge pin diameter?
Post by: amc49 on November 17, 2014, 07:13:16 PM
The point was to show that steel directly to titanium is supposedly incompatible wear surface. Like aluminum to aluminum, there will be problems eventually even if well lubed up. Size or application does not change that. Maybe the degree at which it happens though.

Anything like the big equipment you mention I'm betting bronze or brass bushed there though. Like all the really big fork trucks I worked on.
Title: Re: Door hinge pin diameter?
Post by: 74 PintoWagon on November 17, 2014, 08:33:20 PM
I never looked at my hinges but isn't there brass/bronze bushings that the pins fit into?, my Falcon has them..
Title: Re: Door hinge pin diameter?
Post by: amc49 on November 17, 2014, 08:38:06 PM
Yes. May have to knurl raised area to press these in, some press and some don't, been a while IIRC. Several other pins will work there, a common size OD used on many cars and some pins work by simply cutting them to correct length, I used Ford ones on AMC back in the day and GM on Pinto IIRC.
Title: Re: Door hinge pin diameter?
Post by: 74 PintoWagon on November 17, 2014, 08:47:48 PM
What I thought, then there shouldn't be any problems with titanium pins seizing up..