splitter pusher plate question

[redingp]

I am building a splitter using a 4 inch bore cylinder on an I beam that measures 4 3/4" wide by 10" tall. I will weld a 6" wide plate that is 1/2" thick along the entire top length of the beam for extra strentgh and width. My question is how much of a lip or guide is needed under the pusher plate to keep it safely secured to the 1/2" top plate. Is 1/2" on both sides enough using 1/4" material? thanks

 

[blades]

Lot of force on the push plate. My rails off the side of the beam are made of 1"x 1/4" angle iron. I made the original guides of the same material and promptly destroyed them. The guides are now 1" thick on the side and under the lip. They are bolted to the push plate with 3, 1/2" x 1.25" bolts. I have sheared the bolts a couple times right where the thread starts, but no deformation of the guides or rails since. I can easily cut off and replace the angle iron rails should they get mangled. Learned that lesson from my original I beam when the flanges got mangled.

 

[Toxic2]

over built it the first time and you wont have any trouble..go a little too thin in the metal department and you will find a weak point...I would build the guides as wide as possiable without hitting the I beam center...I used one inch for my sled guides and 1/2 inch to take up the thickness of my beam..I went this big so that i can use a 4 way wedge over my knife when i want too. Gotta take into account there will probably be double the force with a 4way..

 

[mga]

beef it up, man. not too tall tho, keep it tuff and simple:

 

[Toxic2]

Damn..that is one mean looking sled MGA!

I am no expert but i think you can build your pusher plate to whatever size you want ( within reason). Center the ram and add bracing as required. I like a bit bigger pusher plate myself and it would look weird if it was too short especially when my beam is 8 inchs wide..

still need to brace and contrary to my last post i used 1/2 inch as the bottom guide and not one inch..



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Did you find that your ram moved too much and had to u-bolt to the beam MGA? Just curious if i should have a u-bolt ready for mine..LOL

 

[Kevin in Ohio]

Here is how I rebuilt my Dad's from scratch. It's been going strong for 10 years now with no breaks since.

 

[redingp]

Other than the providing extra width, is there even a need for me to add a 6" top plate? The top surface on the I beam is 4 3/4" wide, 3/8" thick on the edges and 1/2" thick in the center. You folks have convinced me to use 1/2" material for the guide instead of 1/4"

 

[1grnlwn]

I would definitely go with the 6" plate on top of the beam. I used 1/2 material all around for my sled it is quite long and weighs a ton.

 

[BrokenToys]

If you got the metal definitely go for as much beef as you can into it. I like that full box setup up there too-may have to consider a change on mine now.

 

[mga]

my theory behind using a shortest possible pusher was it would create less strain on the ram and i could keep the ram as low as possible.


the higher the guide, the more pressure working against it, so, to avoid that, i went with the lowest i thought i should go.

 

[redingp]

Not sure I follow MGA's comment about a short pusher. Are you refering to length or hieght. Overall pusher hieght will be 8" and the cylinder barrel will be 1" above the beam (cylinder pin is about 3 1/2" above the beam). Length of the pusher is 12", is that too long????

 

[davec]

1grnlwn - Some advice on machine design principles here. Make the spacer plate slightly thicker than the beam top flange/web. Then make up the difference with brass shims. They will slide better on steel and wear instead of wearing the beam, so you can replace them. Then you can tighten down the bolts all the way. You are in a bad place with having to get the bolts just right with your thin spacer plate. These are principles we use when designing machines at work for very high cycle work. Take it or leave it.

 

[possumtrapper]

I am building a splitter using a 4 inch bore cylinder on an I beam that measures 4 3/4" wide by 10" tall. I will weld a 6" wide plate that is 1/2" thick along the entire top length of the beam for extra strentgh and width. My question is how much of a lip or guide is needed under the pusher plate to keep it safely secured to the 1/2" top plate. Is 1/2" on both sides enough using 1/4" material? thanks

Depends a lot on the tonnes of the splitter and how many knives etc. Mine is rated at 60 tonne, 8 way, I used a 6inch x 3/4 top plate and the lips that hook under were 1x2 and have 1/4 inch of 'grab' but the beam was modified so where the 1x2 stopped, the beam started, to reduce sideways movement.

Give it too much grab and it has too much leverage on your beam. Sled was 1/2x 16 and we bent that (half the bolts on each side sheared off/stripped nuts off threads.) due to push plate being too high, operated upside down and only 4 bolts either side. Solution was to straighten, replace bolts, then run weld along the joints, and operate right side up.

The weld can easily be cut with a grinder and thin cutting wheel for servicing, and saves a shedload of drilling extra holes thru all those hunks of steel.

Good luck!

 

[mga]

Did you find that your ram moved too much and had to u-bolt to the beam MGA? Just curious if i should have a u-bolt ready for mine..LOL

while some guys disagree with bolting down the front of the cylinder, i looked at it like this: when you are pushing some tuff, knotty wood, the forces will affect any weak point.

makes the whole thing real strong.

 

[1grnlwn]

1grnlwn - Some advice on machine design principles here. Make the spacer plate slightly thicker than the beam top flange/web. Then make up the difference with brass shims. They will slide better on steel and wear instead of wearing the beam, so you can replace them. Then you can tighten down the bolts all the way. You are in a bad place with having to get the bolts just right with your thin spacer plate. These are principles we use when designing machines at work for very high cycle work. Take it or leave it.

The bolts are tighter than heck. If you look closer you will see spacing washers between the spacer and the retaining bar. I am familiar with using brass as a wear surface but have never seen it used on a log slitter, especially one that costs less than $1000 (not including my labor). Your description has left my mind slightly foggy though, could you take pictures of yours so I could see how you did it?

 

[mga]

Not sure I follow MGA's comment about a short pusher. Are you refering to length or hieght. Overall pusher hieght will be 8" and the cylinder barrel will be 1" above the beam (cylinder pin is about 3 1/2" above the beam). Length of the pusher is 12", is that too long????

sorry about that...i meant the height of the pusher plate. mine is 6" hi and 8" wide. you can make the slide as long as you like.

if using a taller push plate to push large pieces of wood, one of them might be pushing against the highest point of your push plate, making it want to bend backwards and putting a lot of stress on your slide..

sorry if i'm not clear in trying to explain it.

 

[1grnlwn]

Depends a lot on the tonnes of the splitter and how many knives etc. Mine is rated at 60 tonne, 8 way, I used a 6inch x 3/4 top plate and the lips that hook under were 1x2 and have 1/4 inch of 'grab' but the beam was modified so where the 1x2 stopped, the beam started, to reduce sideways movement.

Give it too much grab and it has too much leverage on your beam. Sled was 1/2x 16 and we bent that (half the bolts on each side sheared off/stripped nuts off threads.) due to push plate being too high, operated upside down and only 4 bolts either side. Solution was to straighten, replace bolts, then run weld along the joints, and operate right side up.

The weld can easily be cut with a grinder and thin cutting wheel for servicing, and saves a shedload of drilling extra holes thru all those hunks of steel.

Good luck!

Got pict of this beast?

 

[eric_271]

1grnlwn - Some advice on machine design principles here. Make the spacer plate slightly thicker than the beam top flange/web. Then make up the difference with brass shims. They will slide better on steel and wear instead of wearing the beam, so you can replace them. Then you can tighten down the bolts all the way. You are in a bad place with having to get the bolts just right with your thin spacer plate. These are principles we use when designing machines at work for very high cycle work. Take it or leave it.

Sound advice. I started out with 1'' and 3/4'' thick plate and milled a channel just deep enough 9/16'' to do away with any spacers. Looking back i could have milled deeper then added brass shims but after 3 years of use it's pretty clear that it's not likely going to wear the flange's out in my life time.

 

[eric_271]

Not sure I follow MGA's comment about a short pusher. Are you refering to length or hieght. Overall pusher hieght will be 8" and the cylinder barrel will be 1" above the beam (cylinder pin is about 3 1/2" above the beam). Length of the pusher is 12", is that too long????

1" gap between the barrel and beam will be ok but you don't need that much. I have around 1/4'' inch gap on mine. The higher you raise the cylinder in this kind of application is more leverage for it to do things you don't want it to do.

 

[mga]

i built a wood model of the slide when i began building my splitter. this gave ma an idea of what it would look like, what problems i might run into and the exact size of eveything i needed.

i read some where at this site that some one once recommended putting a slight inward angle (maybe 7 degrees) on your push plate and a slight angle on your wedge. kinda like this: /______\


that way, it forces the wood to remain secure between the two. theoretically, it sounds like a good idea, unfortunately i didn't do it...and i wish i did.