Fastening a 1/4" threaded stud

"Buerste" fired this volley in news:X_adnft94LPMUV3RnZ2dnUVZ snipped-for-privacy@giganews.com:

They don't stake in (but could be). They're variously called "sled bolts" or "runner bolts". It's basically a flat-head screw (countersunk, of course), but with no slot.

In a pinch, you could use a flat head bolt, and ignore the slot if it doesn't compromise the appearance on the opposite side.

LLoyd

Sounds like what you want is a self-clinching stud such as these:

Damn. I've seen these -- they're sorta kinda a carrage bolt, but with a knurled shaft instead of square.

PEM makes smaller ones, and may well make the size you want -- I know PEM nuts and PEM studs from hanging out with mechanical sorts designing enclosures, but I can't imagine them not doing the same thing in a bigger size.

Note: It's not going to take oodles and oodles of torque -- turn it too hard and you'll strip out the hole. But that's life.

Stud welder, and weld-on studs. Simple, quick, cheap enough if you have the volume to support it.

If not, maybe you could tack-weld the heads of Elevator Bolts.

jsw

If you're going to weld, use your drill press. drill a hole slightly smaller than the stud. Put stud in drill chuck and drive it in there with unit running at high speed. Makes a great friction weld. Works perfect but i wouldn't want to do more than a hundred.

Karl

I tried on the lathe and couldn't get one to work. When the metal turned red it bent out of line.

jsw

They're also in McMaster Carr:

Give that boy a cookie!

Hmm ... how strong does it need to be?

You might consider using a hefty spot welder to attach the raw stud end to the strap. It sounds as though you have lots of material.

Or -- you could try "fiction welding". Make a drill chuck to hold it which has the threads cut in the inside so it will grip firmly without marring the threads -- spin up to a scary number of RPM, press down with the feed from the drill press, and when the strap and the end of the stud start to glow, just switch off the motor -- or release a clutch, if your drill press has that, and hold it for a short while as it cools. Then on to the next one.

Spot welding will probably be quicker -- and less sensitive to the skill of the operator, but the friction welding is more spectacular. :-)

O.K. We'll be looking forward to the next report.

Good Luck, DoN.

higher RPM less time. I made a bunch of hubs and arbors this way. Once i had the process debugged, all the time was in chucking both parts. Maybe 2 seconds to weld.

Would it be really stupid if I suggested cutting allthread to length, then welding it onto the strip? -

Andrew VK3BFA.

Newer lathe not driven by leather belts?

jsw

Would it be really stupid if I suggested cutting allthread to length, then welding it onto the strip? -

Andrew VK3BFA.

I think a welded stud would be ideal, but if I have to scale production to x-thousands welding would be a bottleneck.

Yea, that's the key...I have no idea yet what volume level I'll need. I really don't see more than a couple thousand a month. And, it'll be cost sensitive, almost an impulse buy.

Now now -- I think there's been enough of that this election cycle already.

Here is a warning "NEVER ASSUME DEMAND". Experience it. Your opinion of way cool is not relevant. Steve

I think you misunderstand. The new product is a separate thing from the "way cool" new machine that was built to service existing demand. Clones of the new machine will make different sizes. This replaces my existing six machines and 50 year old technology that still works well but demands a high skill level from the operator. It will make wheels cheaper, faster and better.

Our estimated demand for the new product is only a thousand or so units a month but the margin will be good.

Penn Engineering "Pem Studs"