nuts 'n' bolts

[Don B.]

I have a '56 C1 and want to locate a source of nuts & bolts with specs similar to the originals that were used to connect the front brake backing plates to the spindles and control arms. The local hardware stores have 7/16" bolts, but these generally have longer threaded areas that are inappropriate for this application. Also, castle-nuts are not all that easy to find. Does anyone know of a good source that is willing to sell nuts and bolts (such as I need) in small quantities??

TNX, Don

[Dave F.]

Re: nuts 'n' bolts

Paragon Corvette http://www.corvette-paragon.com but you might balk at paying $5 for 10 screws.

-Dave

[Don B.]

Re: nuts 'n' bolts

Went thru the 19 pages of 'bolts' Paragon offers - no dice on spindle bolts or nuts that I could see. Thanks anyway.
Don

[Joe L.]

Re: nuts 'n' bolts

Don------

Once-upon-a-time the bolts that you're looking for were available from GM. The fronts used 2 different length bolts, 2 each on each side. The short bolts were known as GM #3693612 and were 7/16-20 X 2". The long bolts were known as GM #3693621 and were 7/16-20 X 2-13/16". Unfortunately, the GM #3693612 were discontinued without supercession in June, 1971 and the GM #3693621 suffered the same fate in Novemeber, 1969.

I don't know what the thread or shank length was on these bolts. However, if they were like most of these front spindle and/or steering arm bolts, they have a longer shank length (and, shorter thread length) than "standard" bolts of the same overall length.

You can look high-and-low and I don't think that you'll find bolts of the original configuration. Here are some options for you:

1) Look for good used bolts. The same bolts were used for the same application on all 1951-54 Chevrolet passenger cars. The problem is that finding 51-54 Chevrolet passenger cars is not so easy as it used to be;

2) If you have unserviceable examples of the bolts, measure the unthreaded shank length. Then, go to the hardware store and see if you can find overall LONGER bolts with the same shank length or just a slightly shorter shank length. Then, cut off the threads so that the longer bolt is "transformed" into a bolt of the same overall length as described above. This is EXACTLY how I "re-create" the special configuration bolts used for steering arm-to-spindle for 63-82 Corvettes. You don't need a shank that's exactly the same length as the originals---it only needs to be such that a small portion of the unthreaded shank enters the innermost unthreaded hole of the clamped assembly.

From a strength standpoint, the hardware store Grade 8 bolts will be just fine.

As far as slotted nuts go, use extreme caution. Most of the suspension slotted nuts used for C1 and early C2 Corvettes were SAE grade 5 (GM-286M) and a few may have been SAE Grade 8 (GM-301M). You want to use a minimum of SAE Grade 5 slotted nuts for ALL suspension applications. The slotted nuts available from most hardware stores, most specialty industrial supply stores, some automotive stores and, even, some Corvette restoration parts vendors are NOT SAE Grade 5 or greater. They are UNGRADED and described only as "steel". These are not suitable for ANY Corvette suspension application. So, how do you know if they're the latter. Well, a "clue" is that if they're zinc plated, the chances are about 95% that they fall into the UNGRADED category. Some Grade 5 slotted nuts are zinc plated. However, if you find slotted nut that are plated, then you want to ascertain FOR CERTAIN what the material class is.

By the way, technically speaking, very few, if any, nuts used on Corvette suspension systems were CASTLE nuts. Virtually all are classified as SLOTTED nuts. While functionally similar and generally interchangeable, the configuration of slotted and castle nuts is different.

[Terry M.]

Re: nuts 'n' bolts

Don,
If you live in or near a large community you will likely find a fastener supplier close to you. After the used examples Joe cites, that is your next best chance. You may still have to purchase the next longer size bolt and cut it to length, but relative to the hardware store or home supply center you will be assured of the grade of fastener you are purchasing. You will also have the benefit of examining the fastener before purchase, something that is lacking when purchasing from the usual hobby vendors. In my case I have found some of these fastener suppliers are staffed with folks who are very knowledgeable about their product. Of course buying these fasteners by the ones and twos will not be inexpensive, and some have minimum purchase requirements. But then if it were easy everyone would be doing it.

[Joel M.]

Re: nuts 'n' bolts

It is my understanding that Dick Fortier( ex paragon) has recently re-entered the fray with an extensive and growing offering of Corvette fasteners. Worth a shot.

[Dick W.]

Re: nuts 'n' bolts

A good resource also would be Fastenal. They are a nationwide chain specializing is fasteners. Downside is that they require you to buy a "package" of bolts and or nuts. No onesies and twosies. They stock grade 3, 5, and 8 bolts and nuts

[Harmon C.]

Re: nuts 'n' bolts

Don
Over the years at Carlisle and Bloomington some Vendor has brought a heavy box of bolts he has removed from the Corvettes he parted out. I have bought up thease treasures and now when I need a bolt I have it in stock but I need to dig for them. I payed $150. for about 200#s of bolts once. I have them sorted large,small, and interior. I remember being laughed at carrying this stuff to my truck but it makes restorations easy. Not sure if I have many C-1 bolts unless the same bolt was used in later Corvettes. I will look for the bolts Joe described. I can't sell them on this board(rules are rules) but I will E-Mail you off line if I find something.

Lyle

[Ed H.]

Re: nuts 'n' bolts

Joe, I had Dick make up an order for me on some very obscure machine /clutch head screws. Also two bolts that I could not find. Both orders turned out great, and he is a nice man. Will help anyone with anytype of fastner.

[Don B.]

Re: nuts 'n' bolts

Lyle - Thanks for the response. You more or less have confirmed my suspicions that some hardware is difficult to find. I'm not attempting to restore my C1 to factory, but would like to replace some aging hardware with similar pieces that are not necessarily factory. My old bolts have taken on new value.
Don

[Ed H.]

Re: nuts 'n' bolts

Oh, I reached Dick at (810)750-1472.

[Don B.]

Re: nuts 'n' bolts

Hi Joe -
First, thank you for the wealth of technical information! This data is something I can't usually find. The most interesting part for me is that portion dealing with the 'slotted' nuts. Fortunately, I can still use the original 'slotted' nuts even though they are not as perfect as I'd like - some slightly rounded corners and rust. As for the bolts, all, but one, are useable I think. A few have some rust pitting and that, combined with the boogered up nut were the reason I wanted to find new replacements. I'll be dropping by a local Corvette parts shop today to rummage through their used hardware collection. I appreciate the information you provided. BTW, where can I get a torque spec listing for C1 and C2 fastener hardware??
Don

[Don B.]

Re: nuts 'n' bolts

Terry, Joel & Dick -
Thanks for your input, guys. Fastenal is new to me. You've jogged my memory in the process and I think there's a fastener store (forgotten the name) here in San Jose, CA, that should carry some of what I want - or at least something that I can modify to fit. If I remember correctly they will sell anything in small quantities. The price doesn't matter so much since this is a one time deal. If I ultimately find a source, I'll post it for others.
Don

[Joe L.]

Re: nuts 'n' bolts

Don------

If you're talking about the torque specs for these bolts, the only place that you MIGHT find it is in the Chevrolet Service Manual. You won't find it in the AIM because these bolts were part of an assembly used at St. Louis. The problem is that, at least for C2 or C3, I've never been able to find the torque specs for these bolts in any GM service manual. They may be there for drum brake cars, but the "equivalent" bolts for disc brake cars (mainly what I've searched for) are nowhere to be found. So, I just use and recommend using "standard" torque values for the bolts:

7/16-20 (C1 and all C2)------60-70 lb/ft

1/2-20 (all C3)--------------85-95 lb/ft

[Joe L.]

Re: nuts 'n' bolts

Don-----

I think that you might be thinking of Mr. Metric. I've never been there but I have been told that they have all sorts of fastners (both metric AND SAE sizes, notwithstanding their name) and do sell in small quantities. If you go there, let us know what sort of operation you find.