how to install stainless studs/bolts

ZINC anti seize compound works well for head bolts. This is great shit and should also be used on spark plugs and exhaust nuts. Its available from loctite.

Why is there no mention of triangular shank or waisted bolts for the studs near the pushrod tunnels? The two studs protruding up from the cylinders pass through aluminum and need to stretch the same as the head bolts near the spark plugs. The two studs protruding downward from the head will pass through aluminum when using aluminum cylinders and will also need to stretch. These are leak prone areas and should not be looked over. I've had some requests for these bolts with triangular shanks but its a lot of machine work for marginal pay and I haven't made the jump. But they do work as evidenced for years now with copper head gaskets and .005" copper wire. No leaks.

The triangular shank bolts used to be available from bolt suppliers but I have lost track of who they came from and I'm having trouble hunting them down. I'm running out and I'd appreciate a heads up if someone knows of a supplier (US thread is fine for some of my uses - studs with Time serts as in the photo).




12 pt nuts are available from McmasterCarr

Now you've all got me wondering. I used nickel anti-seize on my SS hardware (and my brass exhaust rose). I had one of those long 1/4-24 bolts on the coil pack seize up and I wrung it in half getting it off. I was more careful with the stuff for the cylinder and head. I suppose the correct Loctite stuff performs the same function as anti seize?

The Loctite stuff probably is an anti-seize. They make at least 13 different types of anti-seize, including one with zinc, number 39901. The recommend it for use in soft metals because it's non-abrasive. It's good to 750 degrees F. They also have them with copper, silver, nickel, and graphite, as well as metals free formulations. They have one that is advertised as particularly good for stainless steel and titanium, but it is described as metals free.

I use their general purpose copper and silver based anti-seizes a lot.

Good summary of their anti-seize stuff here

http://www.loctite.ph/php/content_data/ ... ochure.pdf

Ken

jseng1 said:

ZINC anti seize compound works well for head bolts. This is great shit and should also be used on spark plugs and exhaust nuts. Its available from loctite.

Why is there no mention of triangular shank or waisted bolts for the studs near the pushrod tunnels? The two studs protruding up from the cylinders pass through aluminum and need to stretch the same as the head bolts near the spark plugs. The two studs protruding downward from the head will pass through aluminum when using aluminum cylinders and will also need to stretch. These are leak prone areas and should not be looked over. I've had some requests for these bolts with triangular shanks but its a lot of machine work for marginal pay and I haven't made the jump. But they do work as evidenced for years now with copper head gaskets and .005" copper wire. No leaks.

The triangular shank bolts used to be available from bolt suppliers but I have lost track of who they came from and I'm having trouble hunting them down. I'm running out and I'd appreciate a heads up if someone knows of a supplier (US thread is fine for some of my uses - studs with Time serts as in the photo).

12 pt nuts are available from McmasterCarr

Click to expand...

Jim, I've just been doing some research on the other post about Jim C's approach. I saw your comment(s?) and was quite surprised at how little follow-on commentary it received so I am literally in the midst, around sending youngest to Ireland (3d year studying abroad for college) and middle back to Scotland (3d year Vet Schoo in EDI), of looking up any other info on your work. More to come but meanwhile, please feel free to summarize in this thread...

arbrnrngr said:

jseng1 said:

ZINC anti seize compound works well for head bolts. This is great shit and should also be used on spark plugs and exhaust nuts. Its available from loctite.

Why is there no mention of triangular shank or waisted bolts for the studs near the pushrod tunnels? The two studs protruding up from the cylinders pass through aluminum and need to stretch the same as the head bolts near the spark plugs. The two studs protruding downward from the head will pass through aluminum when using aluminum cylinders and will also need to stretch. These are leak prone areas and should not be looked over. I've had some requests for these bolts with triangular shanks but its a lot of machine work for marginal pay and I haven't made the jump. But they do work as evidenced for years now with copper head gaskets and .005" copper wire. No leaks.

The triangular shank bolts used to be available from bolt suppliers but I have lost track of who they came from and I'm having trouble hunting them down. I'm running out and I'd appreciate a heads up if someone knows of a supplier (US thread is fine for some of my uses - studs with Time serts as in the photo).

12 pt nuts are available from McmasterCarr

Click to expand...

Jim, I've just been doing some research on the other post about Jim C's approach. I saw your comment(s?) and was quite surprised at how little follow-on commentary it received so I am literally in the midst, around sending youngest to Ireland (3d year studying abroad for college) and middle back to Scotland (3d year Vet Schoo in EDI), of looking up any other info on your work. More to come but meanwhile, please feel free to summarize in this thread...

Click to expand...

Triangular or waisted shank bolts are definitely superior and it doesn’t make sense to leave the studs with regular waist thickness when they are just as important – especially with alum cylinders and because of their proximity to the leak prone pushrod tunnels. The triangular or waisted shank bolts spread out the stresses and will stretch and that helps prevent your studs from breaking or pulling out the threads and helps keep the pressure more constant when the alum expands and contracts. On the other hand – many Nortons do fine with the original bolts.

The triangular or waisted shank bolts probably won't keep your head from leaking. Plenty of Nortons with tight head bolts will develop leaks and re-torqing usually doesn't help. The answer I found is a Copper HG with the fine wire around the pushrod tunnels and oil return with contact cement on every surface. I don't like composite HGs because after several retorques your head could start warping whereas copper stays a constant thickness. Every time you mill the head to perfect flatness its just warps again so its better to just take off the high spots with a minimum of material removal. If you can do that with a surface plate then more power to you.

What makes Norton heads leak is the heat/warpage and vibration. You can use “the right stuff” (silicone) which is supposed to work on head gaskets and add some silk string and after a few hot runs you’ll see it leaking oil... take it apart and the sealer and string are right where they’re supposed to be but it leaks anyway. The oil just worms its way past when everything is hot and shaking. The contact cement with fine copper wire holds firm but I can’t tell you why. The more vibration (heavier the pistons) the more the tendency to leak. The vibration is worse at the cylinder base because of the combined weight of the head/cylinders shaking up and down. No matter what you do there will be some oil weepage at the base – a paper gasket will just loosen and this is a big problem with through bolts under the head that you can’t re-torque. An extreme RPM Norton race bike can actually fret and wear the metal between the cylinder base and the cases. I use yamabond only at the base (and with the lightweight pistons/reduced vibration) – there is only an occasionally oil stain showing up at the base. The cylinder base bolts are too short to machine and the long through bolts are stretching already.

Some heads don’t have enough overlapping material between the pushrod tunnels and the front studs. In that case you have to run the fine copper wire all the way around the front of the studs, use blue loctite or sealer on the stud threads that are exposed inside the pushrod tunnels and add aluminum washers under the two front nuts with sealer on the nut threads to prevent leaks.

Photo below shows a experiment that failed but was successful when switching to contact cement and fine copper wire.


Below is a drawing of the cross section of a triangular shank 3/8” fine bolt – the area is the same as a 3/8” fine bolt that is waisted just below the diameter of the thread root.

Jim, I've tried every fastener source I can find, including a lot of mil-specs, and I can't find any reference to a triangular shank bolt or stud. If you come up with anything, please post it. I'm mostly curious to see what sort of application they were designed for. I can't see them having any advantage over regular waisted (or undercut, or reduced diameter, or whatever other label the suppliers come up with) fasteners. The purpose of both is to reduce the cross sectional area down to slightly less than the root thread diameter, so the stress isn't maximized at the start of the thread, and it looks like either type would do that equally well. I also like Jim Comstock's point that you do get more stretch in the bolt without exceeding it's elastic limit than you do with a conventional stud or bolt. It would seem reasonable that using such fasteners would help keep the clamping force more uniform under repeated heat cycles. I can't think of any drawback to using such fasteners for our Nortons, except the difficulty of finding/making them. I really like the look of the CNW ARP fasteners, but unfortunately for me, the two engines I'm currently building use metric head bolts, so I can't use the CNW bits. I do plan to convert the bolts I have to the waisted style, either by cutting and polishing, or by grinding, and will be trying them out on the 1007 soon.

Always something new to try, and I hope there always will be.

Ken

lcrken said:

Jim, I've tried every fastener source I can find, including a lot of mil-specs, and I can't find any reference to a triangular shank bolt or stud. If you come up with anything, please post it. I'm mostly curious to see what sort of application they were designed for. I can't see them having any advantage over regular waisted (or undercut, or reduced diameter, or whatever other label the suppliers come up with) fasteners. The purpose of both is to reduce the cross sectional area down to slightly less than the root thread diameter, so the stress isn't maximized at the start of the thread, and it looks like either type would do that equally well. I also like Jim Comstock's point that you do get more stretch in the bolt without exceeding it's elastic limit than you do with a conventional stud or bolt. It would seem reasonable that using such fasteners would help keep the clamping force more uniform under repeated heat cycles. I can't think of any drawback to using such fasteners for our Nortons, except the difficulty of finding/making them. I really like the look of the CNW ARP fasteners, but unfortunately for me, the two engines I'm currently building use metric head bolts, so I can't use the CNW bits. I do plan to convert the bolts I have to the waisted style, either by cutting and polishing, or by grinding, and will be trying them out on the 1007 soon.

Always something new to try, and I hope there always will be.

Ken

Click to expand...

I've lost track of where I got the triangular shank studs. I thought I got them from Napa or McMasterCarr but I've hounded them about it to no avail. ARP hasn't heard of them. I'll try Rockford fasterners monday. I just took it for granted that they would always be available. Now I am out of them. Some suppliers said they have seen them but had no info on them. It would be easy to machine them - a straight pass or two on three sides of a six sided hex or allen bolt - a slow final pass shouldn't need polishing. If using Whitworth - you could machine an existing available bolt. The only real advantage is being able to grab the shanks with a crescent wrench for installation/removal - and maybe more twist resistance because of the larger diameter at the triangle points.

Thanks, Jim. I spent a couple of hours today at the lathe trying to sort out a good procedure for producing waisted bolts out of standard Norton 850 through bolts. I had a lot of trouble getting a good finish with carbide tools. I ended up roughing them out with carbides, and then finish grinding with a tool post grinder. Still didn't get a really good surface finish. Polishing with abrasive strips finally cleaned them up, but it's very time consuming. I think part of the problem is not enough rigidity in my old lathe. I did something similar 20 years ago to make oversize waisted studs for SRX-6 cylinders to keep them from breaking. It worked, but in the end I just went to ARP and used some off the shelf waisted studs. I'm planning to visit them this week to see if they have anything that will work for the Maney 1007 kit, which uses 3/8-16 head bolts. For some reason I thought they were metric, but they are not. I'm ready to put the head on this engine, and I'd really like to try reduced shank bolts, just to see if I can see any difference.

Ken

lcrken said:

Thanks, Jim. I spent a couple of hours today at the lathe trying to sort out a good procedure for producing waisted bolts out of standard Norton 850 through bolts. I had a lot of trouble getting a good finish with carbide tools. I ended up roughing them out with carbides, and then finish grinding with a tool post grinder. Still didn't get a really good surface finish. Polishing with abrasive strips finally cleaned them up, but it's very time consuming. I think part of the problem is not enough rigidity in my old lathe. I did something similar 20 years ago to make oversize waisted studs for SRX-6 cylinders to keep them from breaking. It worked, but in the end I just went to ARP and used some off the shelf waisted studs. I'm planning to visit them this week to see if they have anything that will work for the Maney 1007 kit, which uses 3/8-16 head bolts. For some reason I thought they were metric, but they are not. I'm ready to put the head on this engine, and I'd really like to try reduced shank bolts, just to see if I can see any difference.

Ken

Click to expand...

You would have to support the bolt on each end when turning or milling - maybe add a side V block or use the tail stock. A hand held die grinder with a flap wheel or similar abrasive against the shank while turning the opposite direction in the lathe is a quick easy polishing technique.

I used a live center in the tailstock against a countersunk hole in the center of the end of the bolt. Jeff Law (engineer and machinist) recommended that I add a coolant spray and use a finer grained wheel with the tool post grinder to get a better finnish. I'll give that a try as soon as I get some time in the shop.

Ken