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Lazarus
26th November 2006, 13:15
Some ideas on tools, plus a little griping...
Plunger tube, a small part that can cause big headaches if not installed right. Let's not get into the bolted on tubes, or brazed on...although that method is sounding better to me for an unfinished gun.

Most of my practicing on this part has been to remove loose factory plunger tubes and replace. In the past I've ground small countersinking areas inside the frame, thinking that the staking tubes would have a better surface to grab onto. The fact that the staking tubes rarely extend all the way through the frame seems to call out for this method. Perhaps not.

Now, the tools. Currently there are 2 tools available for the job. Neither one does the job right, and neither one comes "ready to use". Gunrunners has a screw operated "smasher". The problem is twofold. First, the working point is simply pressed into the steel jaw. It backs out readily on the first try, and requires a good hand with silver solder. Also, the jaw of the tool itself is too large to work on the rear stake. Custom grinding needed.

The other tool is based on the Vice-Grip. The staking point has a shallow angle that won't do much to the stake - more custom grinding needed. The staking jaw also will not work on the rear stake (inside corner of frame) without more custom grinding. I doubt if the Vice grip really has the required force to stake the tube nice and tight.

Custom tool. Apparently once available, but no longer. This one looks alot like the tool used to stake the grip bushings. It is a long narrow bar of steel with a staking point placed about 6" from one end, and fits inside the frame. The other end gets wedged into your vice along with the frame holding fixture. Staking is accomplished by tapping the upper end of the bar, just like the grip bushing operation. This is the best tool, but you will have to make your own.

So here is the opinion section. Is the countersinking operation inside the frame really necessary? Even if the stakes do not reach all the way through the frame?

My opinion is that silver soldering the plunger tube is the way to go on a raw frame. Sure, you might have a job on your hands if it needs to be replaced. But that is a long shot. Most plunger tubes need replacing because they come loose and not because they are crushed.

-Lazarus

wichaka
26th November 2006, 13:20
I use the vice grip style, with some loc-tite on the stakes.

I must be really lucky, as I aint had one come lose yet.

.45nut
26th November 2006, 14:43
I use the one by Gun Runners, can't beat the price.
Nice tight and secure fit. Have not experienced the problem you outlined. Silver soldering was not indicated nor required.
Brownells.com
http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=9489&title=PLUNGER+TUBE+STAKING+TOOL

Hawkmoon
26th November 2006, 14:52
I use the Vise-Grips tool, from Brownells. It does fit the rear leg, with no alterations. I don't try to get a full crimp in one shot -- it takes several, progressive applications. I think putting a small countersink on the inside of the frame couldn't do anything but help, but I haven't done it.

Like Wichaka, I also use a drop of Loctite. Many would probably use Red for this application, but I don't allow Red in my house, so I use medium strength (Blue.)

swampertwo
26th November 2006, 20:51
Just boought the GunRunner tool, countersunk the inside of the frame as instructions said and got a nice, tight tube without the solder. I did "rap" the end of the screw once it was tight to insure the legs were 'staked'.
You do need the inside countersunk to allow the legs of the tube to expand/spread.

1911Tuner
26th November 2006, 21:17
Since staking is essentially riveting, a shallow "well" on the wall opposite allows the staked material to flow and get a good bite. With grip screw bushings, this can be done by displacing the frame material with brute force, and swaging the bushing material into the displaced area. The plunger tube is too thin, even with the mandrel that's supposed to prevent deformation and collapse. Front sight staking is another area where this well can make the difference between an airborne front sight and one that stays put for the life of the gun.

Lazarus
26th November 2006, 22:01
Glad to hear that you all have received workable tooling. Mine must have been made by the shop janitor - I always specify this requirement in my orders. The long bar I described is extra good because the staking can be done in steps, slightly adjusting the angle while whacking the steel bar. It still amazes me that plunger tube staking rivets do not extend through the frame. Guess that's why I have so much experience replacing factory tubes, huh?

Well, I personally DO have a tube of red locktite and not afraid to use it. BTW this stuff does give up the ghost when the metal is warmed up a bit...this is totally different from using airplane gasket cinch on a motorcycle head!! I once had to remove the head from such an engine affixed with same. I took out the head bolts and ran the engine for about 10 minutes before they broke loose!

-Lazarus

berkbw
26th November 2006, 22:32
Glad to hear that you all have received workable tooling. Mine must have been made by the shop janitor - I always specify this requirement in my orders. The long bar I described is extra good because the staking can be done in steps, slightly adjusting the angle while whacking the steel bar. It still amazes me that plunger tube staking rivets do not extend through the frame. Guess that's why I have so much experience replacing factory tubes, huh?

Well, I personally DO have a tube of red locktite and not afraid to use it. BTW this stuff does give up the ghost when the metal is warmed up a bit...this is totally different from using airplane gasket cinch on a motorcycle head!! I once had to remove the head from such an engine affixed with same. I took out the head bolts and ran the engine for about 10 minutes before they broke loose!

-Lazarus

I am interested in this "gasket cinch". I haven't heard of it before - and the planes that I build and fly have no head gaskets. Tell me more.

b-

Lazarus
27th November 2006, 00:35
For some reason, I must have been blowing head gaskets on my MotoGuzzi because I found a can of aviation gasket sealer at the local NAPA and gave it a try. It worked. It was dark brown and really did the trick. As I said, the engine ran fine without head bolts for some time before breaking loose. I disavow any knowlege or expertise on real aviation motors, so save your breath.

-L

smp63
29th November 2006, 13:38
Green Loctite #640 sleeve retainer works better for staking the legs of the plunger tube than the red or blue .

Loctite red and blue was designed for threaded fasteners, whereas green 640 was designed for securing studs, pins. bearings etc.. Works good on the plunger tube.

Ericthenorse
29th November 2006, 15:48
Gaske-cynch is my favorite stuff.... I do a lot of motorcycle work, and lots of VW engines.... I am the only one of my friends who's bug motor does not leak....

Dirt
29th November 2006, 19:22
Green Loctite #640 sleeve retainer works better for staking the legs of the plunger tube than the red or blue .

Loctite red and blue was designed for threaded fasteners, whereas green 640 was designed for securing studs, pins. bearings etc.. Works good on the plunger tube.

+1 smp63. Using 'red' may require a small torch to remove, with resulting blemishes. Loctite is only there to support the staking. The Loctite site does a pretty good job of explaining it's products.

Bob