I'm Finally setting up my Fairbanks/United "0" or 25Lb hammer. I've noticed that my bottom die is much shorter than it should be and I suspect that the top die isn't what it once was either. I've never seen the hammer run and the guy I bought it from hadn't either so I don"t have any history/clues to offer. I only just started setting it up so I can't run it yet to rove os disprove any of my concerns.

As it sits, I'm pretty sure I'm gonna have a problem working small to medium stock. The bottom die is noticeably shorter than it once was and the suspect the top die is somewhat shorter also. With the ram in the down position I have 1" of air between the bottom of the toggle links and the ram guides and 2" of air between the dies. I just guessing but it sure doesn't seem like I'm gonna get nearly 2" of throw from the spring without the toggle links hitting the ram guides. I can't afford to have new dies made and I'm not setup to make them myself so my plan is to shim up the bottom die and it's blocks. the die blocks are separate from the body so it should be fairly easy to do.

My question here for anyone familiar with Fairbanks (and or anyone else) is, what would be the ideal ratio of gap between the toggle links/ram guides and top/bottom dies? I hope to be able to work as full a range of stock as is possible on this hammer...obviously I can just keep adding shims till it's working well...my hope is to get some measurements from some of you to start with and maybe not have to lift the the hammer anymore than is needed.

Thanks

I went out to the shop after posting my post and it dawned on me that the spring controls the throw of the ram as much as anything else. The hammer didn't come with a spring so I got one for a 25lb. Little Giant. With the spring cup backed out basically all the way I've got a solid 1/8" between the coils which is the minimum I've seen called for. 

In my "new to power hammers" mind that tells me that at best I'll get 5/8" (6coils, 5gaps x 1/8") of throw from the spring assuming the spring will compress 100%. Sound right?

 

Where did you get this hammer from?

What makes you think the bottom die is shorter than original?  Signs of wear or machining?  Does the bottom of the dovetail on the die touch the bottom of the DT in the sow block?  Fairbanks don't have particularly tall dies in my experience.  

A little trigonometry or geometric drawings should tell you the movement of the arms given your assumed 5/8" spring compression.  Heck, put some thumb tacks thru popsicle sticks or paint stirrers and mock up the linkage.  

Bueller?... Bueller...?

How do you drive out the lower key?

Good Morning,

Make an appropriate long drift, go through the hole in the Frame.

Neil

I think the wedges should be above the bottom of the hole and there should be opposing wedges, one on each side of the lower die.

Has the anvil settled down, or has the sow block been altered?

On 6/27/2016 at 3:03 PM, doc said:

Where did you get this hammer from?

I beleive it was the one from petersvalley, the idiot guy john hackins or something there who ran the shop for a year sold it off. also threw out alot of old samples with a crew of jerks after the master, Dick Sargent, retired.

The Dupont Fairbanks book says the die gap should be one inch on small and medium sizes. I would also check the anvil.  Some pictures of the whole machine sitting with the die in the downward position would help in diagnosis.

Sorry about not following up on this, my computer died and it took a little while for me to get a new one...

The hammer did come from Petersvalley.

The lower die is roughly a full inch shorter than the top. The face of the lower fuller was much broader than the upper. What I ended up doing was to just shim everything up and reworked the dies to get them better matched. Still getting used to it's quarks but it works well.

I would replace the dies with flat dies. You can do much more work on flat dies.