25 lb. Little Giant power hammer rebuild

[lazyassforge]

Papaw asked if I could re-post the power hammer rebuild thread that was lost in the melt down.

This is the frame of a hammer which has sat in the back of my shop for 7 or 8 years. The hammer is in VERY rough shape, I would have not bought it except I wanted another hammer and the man who owned it insisted I buy this one too or he would not sell me the other hammer!

First Pic.: To start off, the dovetail where the bottom die goes in the hammer frame was broken off. I could have welded it back together but the repair would always be suspect. So I took the frame to Sid Suedmeier in Nebraska and had him cut off the old dovetail and cut a new dovetail so a sow block (later model little giants came from the factory with sow blocks)

Second and third pic.: After a couple of road trips to Nebraska, I got home with the frame with the sow block installed! You can see where they cut the frame and recut a new dovetail in the frame to install the sowblock.

[lzenglish]

That is a nice looking machine! Are there different hammer heads used for different applications for it?

Wayne

[Nolatoolguy]

Looking good.

Thanks for rebuilding the thread.

[Fatboy]

Looking good.

Thanks for rebuilding the thread.

Me Too! Thank you, I really liked this thread. You do remarkable work and I enjoy watching it.

[lazyassforge]

Oh, by the way, this hammer was covered with dirt rust and oil! I had taken a wire wheel on a 4-1/2" grinder and cleaned the frame when I tore it down a few years ago.

Pic 1: The first thing that needeed to be done was to get the pivot shaft for the foot treadle freed up. The years sitting in the dirt and crud in the blacksmith shop had caused the shaft to "grow" together with the frame. In preparation for getting it out, I ran a 1/2"-13 die across the threads to clean them up and make them fit "modern" nuts. Then I drilled a hole through the frame and into the shaft a little. This will allow me to get oil into the center of the shaft and hole.

Pic 2: I gathered up a "coupling nut"(long nut) with a bolt screwed half way through. This will be screwed on the end of the stud to give a place to hammer on without mushrooming the end of the shaft. also a short, heavy tube large enough to clear the body of the shaft and a couple heavy washers and a 1/2" standard nut.

Pic 3: We put the pieces together on the shaft and tighten the nut as tight as we dare! Then spray liberal amounts of penetrating oil at both ends of the shaft and in the drilled hole.

Pic 4: Heat the frame with the torch till it shows some red color in the shade. Tighten the nut on the end to put pressure on the shaft and hit the bolt w/coupling nut with the hammer. Spray more oil. Repeat. I heated this one up several times and then let it cool overnight and repeated the sequence the next night. Luckily it came out with just a couple of cycles!

Pic 5: Getting the shaft out of the frame was the main objective, saving the shaft was just a bonus!

Pic 6: I tapped the hole drilled earlier so I could put a grease zerk to keep the pivot lubricated.

Pic 7: First step finished!

[64longstep/Brian]

I would love to be a fly on the wall of your shop and watch you at work...

[lazyassforge]

The babbit bearings in the frame need to be replaced.

Pic. #1 I put a block under the end of the frame to prop it up in preparation of melting the old babbit out.

Pic.#2 This is what the old babbit bearing looked like.

Pic. #3 Melting the old bearings out. I save the old bearings and remelt them to pour the new bearings.

Pic #4 When the factory poured the original bearings, they used leather shims. I cut mine in a diamond shape.

Pic #5 Shims set in place. They will be adjusted to keep the "dummy" shaft centered and square in the frame.

Pic#6 Checking the dummy shaft for squareness to the ram guides. I use a dummy shaft because the shaft for the hammer has a flywheel and pulleys on it making it difficult to use.

[lazyassforge]

Pic#1 I use locking collars on the shaft for dams to stop the babbit from running out the ends of the cavity.

Pic#2 We use damming compound to seal the locking collars to the frame. Roll the damming putty between your hands to make a slim "rope". Put it between the frame and the collar and push the collar in place squishing the compound out. The chain is used with a rubber tarp strap to hold the shaft in place while pouring the babbit.

Pic#3 The set up I use to melt the babbit. Notice the scrap babbit!

Pic#4 The frame must be heated to 350-400 degrees. When a oily rag smokes when wiped across the frame it is about right! If the frame is not heated, the babbit will "freeze" and make cold joints and incomplete fill in the bearing.

Pic#5 Pouring the babbit. Watch for the babit to leak out of the cavity if you missed getting it all sealed up! The molten babbit runs like water.

[bc_z]

WOW!

excellent tutorial on replacing/pouring new babbit.  Great rebuild.

bc_z

[lazyassforge]

Picture #1. After pouring the bottom half of the bearing I pulled the dummy shaft so the excess babbit can be filed off to leave the mating surface flat for the shims.

Picture #2. I don't know who that old, fat man is! I, er, he is filing the excess babbit off.

Picture #3. The dummy shaft re installed. The plates are temporary shims are used while pouring to give room to put the gasket material shims when the bearings are set up. As the bearings wear, shims are removed to keep the bearing clearance correct.

Picture #4. The top cap bolted in position with the temporary shims in place.

Picture #5. Good help makes the job go better! My wife putting on the daming compound.

Picture #6. Damming compound in place. This bearing is ready to pour!

[lazyassforge]

Picture #1. Pre heating the top cap before pouring the babbit.

Picture #2. Pouring the top cap bearing through the oil reservoir.

Picture #3. This is the oil cavity on the top cap filled with babbit.

Picture #4. The cap removed and ready to rasp the excess babbit off the mating surfaces.

Picture #5. Using a torch to melt the excess babbit out of the oil reservoir.

Picture # 6. Oil hole cleaned out through the cap so bearings can be oiled. Someone had drilled an extra hole in this cap sometime in the past.

[lazyassforge]

Picture #1. Next part of the project. This is the main shaft with the flywheel/crank and clutch spider on the shaft and the clutch pulley next to it. The babbit bearing is worn enough that there is slack between the clutch pulley and the spider. The slack will cause the clutch to "grab" as it engages.

Picture #2. This is the old clutch with the old bearing in place.

Picture #3. Using a weed burner to burn off the old grease and melt out the old babbit bearing out of the clutch pulley.

Picture #4. Using the wire wheel mounted in an air powered die grinder to remove the remaining rust and grease.

Picture #5. This is my fixture for pouring the bearing in the clutch pulleys. The mandrel has a slight taper so when it is time to remove it, you can use a press to get it started out and the taper will let it come easily. I used tape on the outside of the mandrel as an experiment to get it to release easier. I have used spray graphite and acetylene soot in the past for a release with varying sucess.

Picture #6. We put daming compound on the bottom of the clutch pulley to seal it to the fixture.

[lazyassforge]

Picture #1. Bolting the clutch pulley to the pouring fixture. The mandrel is centered in the pulley by measuring with a tape measure. Bolting it down keeps it from moving off center or "floating" up and letting the babbit escape out from under the clutch.

Picture #2. Pre-heating the clutch pulley and fixture so the babbit will flow and not "freeze" when it contacts the pulley.

Picture #3. Pouring the babbit.

Picture #4. Oops! Someone had drilled some holes between the bore on the pulley and the groove where the clutch actuating ring rides. The babbit hit those holes and ran like water! Have to tear it all down and clean up, re-group and do it all again! (With the holes plugged!)

Picture #5. Repour!

Picture #6. Well, I got sloppy and spilled some babbit so the cavity didn't totally fill!

[lazyassforge]

Picture #1. I used some small scraps of babbit and the torch to remelt the top area of the bearing and blend the babbit together to fill the top of the bearing.

Picture #2. The cutch pulley removed from the fixture. The mandrel still needs to be pressed out of the babbit. (no, the tape didn't work very well to release the babbit)

Picture #3. The babbit bearing is bored out to size (a couple thousanths clearance from the spider) and the clutch friction area cleaned up while still in the chuck so both areas run concentric with each other.

Picture #4. Checking the fit on the spider.

Picture #5. Clutch/shaft assembly in place!

[Papaw]

Short of being a video, this is the best step-by-step rebuild I nave ever had the pleasure to witness. Even when you make a mistake, you show us!