Sunday, July 31, 2016

An Old Saddle Tap

This is probably not worth a salvage attempt.

This saddle tap was on some copper pipe that I picked up from the roadside while out for a walk. The copper pipe was certainly a worthwhile find, but this tap appears to be past it. I only took it off the pipe out of curiosity.

The valve stem is seized. The gland nut has been tightened down all the way, and it appears to have a crack in it, so the valve is unlikely to ever again be leak-free at the stem. But, it's not as though I have anything better to do, so let's at least examine the thing, and maybe learn something about saddle tap failure.

- - -

Here it is fully dismantled.

The gasket is a ruin -- a replacement could easily be made.

The clamp halves and the 1/4" - 20 fasteners are indestructible, and could be wire-brushed back to a decent appearance.

The valve stem and the gland nut are in rough shape; you can see the crack in the gland nut in the photograph. The valve stem's handle is not meant to be non-destructively removed from the valve stem, so that makes servicing of the valve stem and its packing a challenging proposition.

The valve seat is way down inside, and difficult to see to examine its condition, which is unlikely to be good

But just for the heck of it, I'll see if I can drill the handle off from its swage to the valve stem, and get a look at the valve stem's packing.

- - -

On second thought, maybe not. This thing is truly past it. Here's a close-up view of the valve stem portion. (I managed to get the packing washer to reveal itself.)

That packing washer is probably an item that I'll never be able to get a new replacement for, and re-using the existing one is a pretty iffy proposition.

I've spent enough time on this. I'll salvage the 1/4"-20 screws and nuts, and the saddle halves and toss the rest. Some things are just not worth pursuing.

# # #

# # #

Improving A Cheap Set of Forceps/Tweezers

Over at The Whole Garage Catalogue recently, I posted an item about a cheap pair of forceps/tweezers. Here's the post:

- - -

A Pair Of Forceps/Tweezers Of Some Sort

There's no maker's name on them, and they look cheaply constructed. The pivot is a bit sloppy, and the tips align poorly.

With a bit of work, I could improve the thing, and possibly have a useful tool for something-or-other.

I'll stash these in my spare tools drawer against the day that I feel like getting after them.

# # #

Well, I feel like getting after them. So here's what I need to do to improve this tool:
  • Strip off and possibly replace that rotten sleeving.
  • Reconstruct the sloppy pivot.
  • Align the jaws.

That wasn't difficult to scrape off with a utility knife. The tool is reasonably clean now.

I have some red 3/16" heat-shrink tubing on hand that might make excellent replacement sleeving. That can wait until I've dealt with the pivot and the alignment.

The Pivot

The original pivot was a 1/8" diameter rivet. I cut off its end and discarded it.

The pivot holes are slightly oversize -- that accounts for the sloppiness that I observed in the pivot's action.

I can drill out the pivot holes slightly to accommodate a 6-32 screw, but there's a caveat regarding the use of a screw as a pivot pin. It's a very poor practice to have a pivot point operate on a screw thread. You want a pivot point to operate on a full rod/cylinder. So, what I need here is a 6-32 screw that has an unthreaded shank portion that's just the right length to serve as the pivot point, while providing thread enough to be fastened by a Nyloc nut.

I have some 1 3/8" long 6-32 hex socket head cap screws with unthreaded shank portions to them, but the unthreaded portions are too long. So, I threaded one of the screws further, and now I have a screw that should serve nicely as a pivot (once I've cut it down to correct overall length). Here's a view of the screws I've just been on about.

At the left is an unmodified screw. At the right is a screw that I've threaded further. That one's going to be my pivot screw.

The pivot holes need to be enlarged slightly to accept a 6-32 screw, and it's important that I get as close a fit as possible so as to minimize slop in the pivot. Consequently, I didn't just go with the conventional 6-32 clearance drill size of 9/64". I miked the screw's shank, and chose a drill size based on that result.

The screw's shank measured 0.135". The closest clearance drill size is No. 29 (0.136"). So I went with a No. 29 drill, and that gave me just the outcome I was after -- a relatively slop-free pivot. Here's a view of it assembled without a nut.

Now I just have to cut the screw down to correct length, add a Nyloc nut, and my improved pivot will be done.

- - -

And here we are.

A slop-free, reasonably tidy pivot.

All that's left is to lubricate the pivot, align the jaws and add new sleeving.

- - -


I've got a decent set of forceps/tweezers from what was a piece of offshore junk. Very satisfying.

# # #

# # #

Friday, July 29, 2016

Material Is Where You Find It

A house painting outfit came by a while ago and asked my wife if they could plant a promotional sign on our front lawn. They were doing that all over the neighbourhood. My wife let them, and the sign stayed for days. The painting outfit never came back to retrieve the sign, and I finally pulled it up and stashed it under the carport. Today it occurred to me to dispose of the thing. Here's a view of the sign.

It's a 32" x 20" plastic sleeve affair draped over a skinny steel rod frame. Take away the plastic sign and here's what's left.

About 90 linear inches of 4.5mm diameter steel rod (about 23/128" -- just shy of 3/16").[1]

It's a bit of an odd diameter, but I might find use for it for something-or-other. The price was certainly right.

- - -


[1] It's undersize for threading 10-24 or 10-32, though I've half a mind to try it and see if I still get a useable result.

# # #

# # #