Mechanical hammer brake adjustment

[beaudry]

 All three of my  mechanical hammers have brakes that can stop the ram at any point in the stroke.

The Beaudry #7 [200# ] motor driven hammer has the factory brake  that engages with the same linkage that operates the clutch. The brake shoe is lined with thick belt leather glued to the cast iron shoe with Gorilla glue. I replace the leather every few years .

The Little Giants [25# and 100# ] have brakes that I built , as LG did not include a factory built brake  in their design .  

The 100# hammer has a band brake lined with some sort of synthetic belting that covers about half of the top of the flywheel and is actuated through the same linkage as the clutch.

The 25# has a leather lined brake shoe, similar to the Beaudry design.

All of these are adjusted to smoothly grab and stop the flywheel at the same time the mechanical clutch is acting to disengage the drive from the hammer mechanism. 

It takes some time to get this action coordinated ,so that the clutch can fully  disengage and the brake can stop the flywheel from running on,   but once set, the hammers have excellent control and are very responsive. It is critical however, that the clutch is set up, lubricated and adjusted properly before the brake is adjusted so that the two are working together, rather than fighting each other.

Even so, I've found that sometimes after running the hammers hard for a number of hours , the response  becomes erratic. This is more noticeable in warm weather.

I finally solved the problem by slightly loosening the brake, finding that as things heat up the flywheel must be expanding slightly, just enough to make the brake/flywheel interface too tight to release easily when I first step on the treadle.

I'm curious what kind of brakes other people have on their hammers and how well they work.

A brake makes them so much more useful as well as safer and being able to take one hard hit  and then stop allows the use of all kinds of top tooling.   

 

[Frosty]

Leather tends to get grabbier when warm but I suppose heat expanding the crank plate on mine could account for it getting grabbier after a while. I did run my finger tip over the leather belt after it'd started being more . . . positive and it wasn't as slick as it is cold. I don't know if that's significant it doesn't make a lot of difference on my 50lb. LG but it's noticeable. I'd need to tighten mine up some or make the shoe cover more of the crank plate if I wanted a positive stop.

I like my brake, it's so much nicer than having a hammer coast to a stop or keep going. I like a machine to stop when I want it to.

Frosty The Lucky.

[Sanderson Iron]

Here are some pictures of the brake I put on my 250 pound Murray.  It works really well, with snappy starts and sudden stops, even on the down cycle.  This hammer can hit hard, single blows, but when I hammer continuously, the brake doesn't heat up or wear that I can tell.  I've never had to replace the leather on the band, and it's been there for 18 years.  There's no difference between how it works on the first blow and how it works after an hour's run.  It's adjusted so that it releases as I press the treadle, then the hammer starts, though the timing is pretty close.  My Hackney's clutch releases much earlier so that I can slowly drop the ram and touch the work, then lift it and strike.  That's a more complex system though and's built into the hammer.  If anybody wants to see it, I'll show it in another post. 

On the Murray's clutch, there is a band, 1/8" by 3" which goes up and over the flywheel.  This has a leather belt riveted to it with copper belt rivets.  One side is anchored solidly, the other connects to a long arm which engages the brake.  The pictures show how this better than I can explain it.  One side, the side near the brake, is about 3 1/2" from the fulcrum; the other side, with the spring, is 38" from the fulcrum.  That's quite a bit of leverage.  There's a link just below the spring which connects to the treadle. The spring is quite stout.  To get it tight, I threaded a rod with a hook on one end so I could draw it up.  This spring also raises the treadle, so the original spring there had to be lightened.  

My 25 pound Little Giant doesn't have a brake.  I've never felt it needed one.  I use it mostly for swaging and straight-forward forging itty-bitty things, so that might be part of it; but with the lighter hammers, you can loosen the spring so the ram is more floppy, then you can get pretty close to single blows even without a brake, though they won't be as strong.  I once worked in a shop with a 50 pounder which was essentially brakeless, and that's how I got it to do singles. 

I hope this was worth the read, Beaudry.  Do you have it in your heart to show us some pictures of your brakes?  

Joel

Post Script:  I don't claim credit for this brake design.  I think I saw it in an Anvils Ring in the early '90s or so.  Can't remember. 

[K A Willey]

Beaudry , All my Beaudrys I adjust when I am running them they are always alittle different and I find so am I with the day and the work I have a small brake shoe on my 25 Little Giant all lined with Leather I have used a lot of other matierals over the years and my preference is leather.

Sanderson Iron do you have any pics of the direct acting bake on you Hackney?

I'll take a few of the Beaudry brakes tomorrow

[Sanderson Iron]

I had taken some pictures, but they're not very good.  I'll take some that are more clear when I'm back in the shop on Monday.  

I look forward to seeing the Beaudry pics.  

[K A Willey]

Here are a few pics of my Beaudrys brakes 2 are slack belt models and one is a clutch, the brake arm depresses  the brake as you step on the treadle as the clutch or the idler arm engages the belt, as you let off the treadle the brake arm pushes the brake up to make contact with the pulley on the slack belts and the spider on the clutch model, it is adjusted by means of the big set screw and lock nut on the bottom of the brake box. they work extremely well when adjusted properly and will stop the 200lb ram anywhere on its stroke  works very well to push punches into a bolster block  and the 75 will stop very rapidly to do singles, doubles or what ever you want, very nice for spring swage work. My 25 has a small shoe on the treadle linkage that just drags on the edge of the flywheel alittle when feathering in the clutch and lets me stop the hammer on the upstroke other than that I have no real use for a brake on that hammer as I want the very rapid blows it delivers on light and thin work hope the pics show them clear enough.

[beaudry]

Willey,

What's the tube  running down from above the brake ?

[K A Willey]

Beaudry,

My slackbelts have drain tubes on the back of the crank bearing not all of them have it most the later slack belts do never have seen it on a clutch model the clear tubing put on the brass drain pipe to divert the oil into a container.

 

[forgedinfire123]

I removed the brake on my hammer, it simply stops when I take my foot off the pedal

[K A Willey]

Most hammers do stop when you let off  the treadle, it all depends on the work you are doing IMO

 

[Sanderson Iron]

Mr. Willey, your hammers are just delicious.  Wowsers.  I want one.  Nice shop too, by what I can see of it.  (Drool drool)

Here are pictures of my Hackney's brake and control system.  This is a 100 pound hammer.  There are three controls which happen simultaneously: the clutch, which controls the RPM; the brake, which stops and starts the ram; and the air valve, which controls the stiffness of the spring (the air cylinder).  The standard on this model is hollow, with the links inside, but he anvil, just below the die, is solid.  (The double standard Hackneys have solid standards and anvils.)  Interesting, the Little Giant style hammers are opposite as far as I have seen, with a hollow anvil and a solid standard. 

The brake itself is pretty simple.  The left hand ram guide (which is bronze) is in a slot with a wedge behind it.  As the wedge is inserted, the guide moves over, locking the ram.  This is a very positive lock.  I can put a three foot board between the dies, lock the ram, and put my weight on the end of it without lifting the ram.  This lets the ram be used to hold for upsetting, twisting, switching ends with the tongs and so on.  I have to say though, when oil gets on the guides from above, the lock is less effective, so when I need to lock it securely, I squirt a little kerosene on the guides.  Seems to work fine.  

There is a link connected to the wedge which has a gear thingy on the end that connects to another gear thingy which, when rotated… Oh fiddle, you can see how it works without my thingy definitions.  It's the third picture.

Here's how the air spring is adjusted: there's a plunger valve on the back of the air cylinder which controls how much air is released. The faster the hammer runs, the more air is retained, so the stiffer the spring.  With a Little Giant style hammer, there can be times when the ram will flutter and not hit.  That's because the spring is too stiff for the blow being struck.  If the spring were lighter, that wouldn't happen.  Well, the Hackney gets around that issue by having the spring get stiffer as it speeds up and lighter as it slows down.  It never, ever, flutters, but it tends to have a deader blow, and it's difficult to get a light, fast blow like is so wonderful with most mechanicals.  This hammer has amazing low end control though.  The fourth picture shows the slide which adjusts the air control.  I'm sorry it's not very clear.  I should scan in the patent drawings, which are much more explanatory.

I hope this isn't getting too wordy.  Just skip over this gobble-dee-gook and look at the pictures if you'd rather.

The fifth picture shows the links, though it's hard to make out for all the mess in the background.  Sorry 'bout that.  To the right is the brake, the upper middle is the air control, and the left shows the clutch links.  This clutch is a cast-on-cast clutch, believe it or not--no leather or brake lining.  It has a steeper cone than other clutches I've seen, so that's probably how it keeps from sticking.  It has to be kept oiled, but then, so does a Little Giant.  There's a turn buckle thingy (here we go again) that is the clutch's adjustment.  

So to answer your question about timing, Beaudry, I have it timed like this: first, the treadle unlocks the brake.  This lets it fall on the work, but how fast it falls is still under the operator's control.  I can set it down gently, or I can let it fall.  This is really nice for straightening bars, pushing drifts, center punching and so on.  But anyway, as the treadle is pushed, the clutch begins to engage, causing the air cylinder to lift the ram.  As it speeds up, the spring gets tighter, and the blows get snappier.  The brake will stop the ram anywhere in the stroke, more or less.

There is no ram height adjustment on this hammer.  It will hit high and low pretty much the same, but you cannot stack really tall tooling under it.  To solve that issue, I go the other way, with a bolster die and other things.  But this thread is supposed to be about brakes, not dies.  Well, I'll toss one in.

Okay, sorry for the book.  That was ridiculous.  If you have any questions, I'll try to answer them with fewer words.  

Joel

 

 

 

 

 

[K A Willey]

Mr. Sanderson Beautiful hammer and thank you greatly for the pictures and your comments on my hammers, very few of the Hackneys around, would love to come to your shop some day,  like your bolster die I have a similar on  my Little Giant for making rivits. My #7 Beaudry is a cast to cast clutch as well has excellent control when tuned right can deliver a very light blow or really fast single blow. one really nice thing I like with my Beaudrys is the ability to have a very fast penetrative blow on thin stock and move quickly by shorting the stroke it allows me to run 225rpm on a 200 lb hammer, very effective for some types of forging. my 75 will run 350 it is amazing the difference you can achieve on forging times on thinner stock over a airhammer or press, they all have there place don't get me wrong just my hammers are the most versitale for the work I do, thanks again for taking the time to post the pics.

 

 

[Sanderson Iron]

I didn't know the Beaudry was cast to cast too.  Interesting.  Where're you located, Willey?  I'm in southern Michigan.  I'd love to see your hammers too.  

 

[K A Willey]

I am in northern Wyo, Little giant made a cast to cast clutch for a few years also, not to many of them left' IMO they were their best clutch.

[K A Willey]

Sanderson Iron, Beaudrys are like your Hackney, hollow frame and solid anvil, except for the utility hammers they made.

[basher]

Sanderson Iron, thanks for posting about that lovely hammer. I will dig up some pictures of the brakes on my Goliaths.

[KYBOY]

here is the brake on our hammer. works very well, just need to clean the oil off the pad every so often..This hammer will stop when you let off the pedal but the brake allows you to make hard single hits without accidentally over rotating a double tap. Just smash the pedal and let off..

[Sanderson Iron]

That's quite the brake.  Where and what is the spring?  Is it separate from the pedal's spring?  What size hammer is it? 

Thanks for starting this thread, Beaudry.

 

[KYBOY]

That circular band you see wrapped around the flywheel is both the brake and a spring. The lever that operates it is connected to the foot treadle..When you push down it opens up the band, when you let off the band springs back and closes.