Front Axle / Front Suspension: Pressing in hub studs

[NCDave51]

Working with new studs from S-I to press into my front Lark hubs. They have the original smooth shank (non-splined) and the correct shoulder and length. being smooth, they are an interference fit by design.

While I managed to get one in with some heat, some WD-40 and a lot of hits with a maul, I let a local shop try and put in the rest in a field with a 3 ton press now looking for other machine shops in the area which seem to be as rare as hens teeth these days.
Any secrets out there from what folks have used? 6 ton press? Heating the bolt not the hub, heating both, etc.?

Much appreciated.

[r1lark]

I've never had that much trouble fitting studs, either the ribbed knurled type. or the smooth type that are made to be swaged (swedged?) in to hold the drum to the hub. In fact, seems like the smooth type went in a lot easier, but it's been a number of years since I installed any of those.

6 ton press isn't too awful big, but should get the studs in if the size is correct. I've put them in with an arbor press before.

What is the interference fit measurement?

[NCDave51]

Will double check when back to house.

You and I are close by here in the NC Piedmont - all the machine shops here in Greensboro seem to have disappeared. Do you have any recommendations over near Winston-Salem?

[NCDave51]

Ok - all nominal 5/8”. Lug shoulder past the initial (insertion) taper is 41/64” and hub holes are 39”/64”.

All lugs and holes are the same and concentric, no ovality thank goodness.

[r1lark]

Ok - all nominal 5/8”. Lug shoulder past the initial (insertion) taper is 41/64” and hub holes are 39”/64”.

All lugs and holes are the same and concentric, no ovality thank goodness.

So that's 2/64" or .031" diametrical interference. That's huge, no wonder it's so hard to get them in!

[r1lark]

Will double check when back to house.

You and I are close by here in the NC Piedmont - all the machine shops here in Greensboro seem to have disappeared. Do you have any recommendations over near Winston-Salem?

No, I'm in the same boat now. Up to about 8 months ago, I had access to a well equipped general machine shop, and excellent machinists but now that I'm retired that is gone. As far as specific automotive machine shops, that's been an issue for a years around here too. All the good ones are busy with racing work, so it's hard to get anything done.

[NCDave51]

No, I'm in the same boat now. Up to about 8 months ago, I had access to a well equipped general machine shop, and excellent machinists but now that I'm retired that is gone. As far as specific automotive machine shops, that's been an issue for a years around here too. All the good ones are busy with racing work, so it's hard to get anything done.

That's where I'm thinking heat or dry ice would help. Two have gone in with force, but I'm sure others have found other ways.

I did end up finding a CarQuest machine shop that's still open and does have a machine shop. Will check in with them after Easter Weekend.

Thanks all.

DW

[r1lark]

That's where I'm thinking heat or dry ice would help. Two have gone in with force, but I'm sure others have found other ways.

I did end up finding a CarQuest machine shop that's still open and does have a machine shop. Will check in with them after Easter Weekend.

Thanks all.

DW

Dave, see post #5 -- 31 mils is not a reasonable interference fit in my mind - it's way way too much. Something is wrong. Even for a knurled stud this would be a lot of interference fit. For a smooth stud, a couple of mils interference should be enough. But aren't the smooth studs meant to be swaged in?

[NCDave51]

These are the OEM hubs and I removed what were likely the OEM 10” hubs that were swaged on to the studs (3-point barbs at outboard face of drum). When I cut off the studs to free the drum I still had to drive the &@#* out of the stud remnants to remove them from the hubs. Measuring them now they’re exactly 40/64”, previously a 1/64” interference (0.016”).

Ordering these new studs from Studebaker Int’l, they looked to be exact matches, and I figured I’d be pressing them back in first, then the drum. Again they are 41/64”.

I agree ~0.032” seems high, but they have to be an interference fit to handle the ~70 ftlbs we tighten the wheels on with. I missing something.

Perhaps I can have the shop open up the holes somewhat - what should the cold interference be then? Can’t find anything in the manuals.

Thanks Paul.

All, keep the responses coming.

[r1lark]

Dave, what is the Studebaker part number of the studs? Got pics you can post of the studs, back side of the hub, etc?

[Videoranger]

James,
Depending on material it could be anywhere from 3-5 thousandths for steel or 5-8 thousandths for aluminum is what you would want the hole to be undersized.

Regards,


Kevin Scholl
Dorman Products
Tech Line Specialist
215-712-5126
800-868-5777 x 5126


This is the interference fit specifications emailed from Dorman that makes the smooth side studs. When I replaced the front studs on 62 Hawk front drums I had a machine shop ream the hub and drum holes out to proper fit and then had them swage them with a tool they made for me. The swage tool is simple for a machinist to make. reamer had to be special ordered for the job. I paid the shop $140 for reaming and pressing in and swaging 10 studs and kept the swage tool. I supplied the Dorman 610-036 studs. I replaced one drum with an NOS one and reused the other side. Had both Drums turned .010 over. I had two studs with messed up treads on used drum, so replaced them all. I still need to replace all the steel lines and then reassemble brakes with all new master and brake cylinders, and relined shoes, new hardware, new bearings and seals, etc. , complete routine 59 year brake and axle service. tires still look new, but have 2013 date codes so will need to replace those too. Best to be safe. Decided to treat the GT to some new alloy wheels while I'm at it.

[r1lark]

James,
Depending on material it could be anywhere from 3-5 thousandths for steel or 5-8 thousandths for aluminum is what you would want the hole to be undersized.

Regards,


Kevin Scholl
Dorman Products
Tech Line Specialist
215-712-5126
800-868-5777 x 5126


This is the interference fit specifications emailed from Dorman that makes the smooth side studs. When I replaced the front studs on 62 Hawk front drums I had a machine shop ream the hub and drum holes out to proper fit and then had them swage them with a tool they made for me. The swage tool is simple for a machinist to make. reamer had to be special ordered for the job. I paid the shop $140 for reaming and pressing in and swaging 10 studs and kept the swage tool. I supplied the Dorman 610-036 studs. I replaced one drum with an NOS one and reused the other side. Had both Drums turned .010 over. I had two studs with messed up treads on used drum, so replaced them all. I still need to replace all the steel lines and then reassemble brakes with all new master and brake cylinders, and relined shoes, new hardware, new bearings and seals, etc. , complete routine 59 year brake and axle service. tires still look new, but have 2013 date codes so will need to replace those too. Best to be safe. Decided to treat the GT to some new alloy wheels while I'm at it.

James, this is some really great info, especially the info from Dorman, thanks for posting for posterity!

By the way, I found some interesting info on swaging from the early Ford guys: http://www.fordgarage.com/pages/swaging.htm
Google 'swaging wheel studs' and a lot of info comes up.

[bezhawk]

I use this from Lisle Tools... The back side is a thrust bearing, and the other side is tapered and you put the lug nut in and tighten it, and it pulls the stud into place.

[NCDave51]

Dave, what is the Studebaker part number of the studs? Got pics you can post of the studs, back side of the hub, etc?

The S-I part number is 196930.

[r1lark]

Looks like that is probably a Dorman 610-036 that James references in post #12. The interference fit that the Dorman rep gave James should work.