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Old 12-08-2013, 08:41 PM   #11
Brandon Heavey
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Re: Need advice for jerk blocks getting to much bounce

Hey Luke,

I'm realizing I didn't have a picture up that shows the insides of the boxes. If you imagine pulling the plywood off the top you'd see three "ribs" inside. So there is the perimeter of the box which you can see in the first pic here:

http://www.heaveyduty.com/2013/05/je...ulling-blocks/

and then within that perimeter running the shorter dimension of have those three ribs. In the case of the large box shown, each of those ribs is a 2" x 10" which makes the boxes quite beefy and helps keep them in place.

Wish I had a better picture, but I'm actually out of town right now and don't have access to my image library to see if I got a better shot of the insides.

Does that answer you question though?
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Old 12-09-2013, 08:54 AM   #12
Luke Conner
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Re: Need advice for jerk blocks getting to much bounce

Yeah, that's what's inside mine. I really like your addition of the plywood. If I build another set I'm definitely doing it your way.
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Old 12-09-2013, 09:06 AM   #13
Brandon Heavey
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Re: Need advice for jerk blocks getting to much bounce

Awesome man... good luck. Let me know how it goes if you build more!
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Old 12-09-2013, 05:51 PM   #14
Mike Gin
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Re: Need advice for jerk blocks getting to much bounce

I've already built a set but I do like the design. I can't see where you used anchor bolts they all look like drywall screws to me. Did you glue as well for added strength?

So to get about the same height I got (3 - 12" boxes and 1 - 6" box) looks like your cost is $321. I think I spent high $200s somewhere between $280-$300. The nice plywood put you over the top!

I did some calculations and figure to do 3 - 12" boxes, 1 - 6" box, and 1 topper like rogue in all plywood would take 10 sheets of plywood. Since they glue and staple it together you save the cost of fasteners (which surprisingly add up pretty quickly). I would probably do that if I could do it again. I think it would cost me about $100 more in the end.
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Old 12-09-2013, 06:02 PM   #15
Brandon Heavey
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Re: Need advice for jerk blocks getting to much bounce

Yeah, Mike sorry... I really need to get some better pics up. You're right, I mostly used drywall screws, but I also used lag screws/bolts on the longer sides of the boxes to fasten the permitter pieces to the internal ribs. With this arrangement these boxes have held up like a tank. I didn't use any glue, didn't seem to need it.

And yeah... you could shave a few bucks off my costs by getting cheap plywood
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Old 12-09-2013, 11:09 PM   #16
Mike Gin
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Re: Need advice for jerk blocks getting to much bounce

Hmm... I'm thinking of selling mine and building plywood ones. Any takers?

http://gingym.blogspot.com/2013/12/j...ks-anyone.html (wfs)
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Old 12-10-2013, 11:57 AM   #17
Mike Hollister
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Re: Need advice for jerk blocks getting to much bounce

I would do plywood ones if I had a table saw. You need to make really accurate cuts. The lumber store can rip the sheets for you too. I think you could get good stability if you staggered the double plywood wall, so the bottoms nested completely in the tops.

I'd need to map it all out to see how to bet minimize the waste of plywood.
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Old 12-10-2013, 01:27 PM   #18
Harold Collins
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Re: Need advice for jerk blocks getting to much bounce

[quote=Brandon Heavey;1210121]Yeah, Mike sorry... I really need to get some better pics up. You're right, I mostly used drywall screws, but I also used lag screws/bolts on the longer sides of the boxes to fasten the permitter pieces to the internal ribs.

I suggest looking into these instead of lag bolts
http://www.fastenmaster.com (wfs) the headlok model is stronger than comparable bolts, lighter and more economical.

Also the wood screws that are star head instead of Phillips need minimal pre drilling and don't strip.
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Old 12-10-2013, 02:09 PM   #19
Mike Gin
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Re: Need advice for jerk blocks getting to much bounce

Mike Hollister I'm down to 9 sheets of plywood. That would be for the (6) 12" boxes, (2) 6" boxes, and (2) 2.25" toppers. Oh and I have a table saw...

Harold I used similar screws (rugged structural) and they turned out to be not that different in price to anchor bolts and washers. I was shocked at how much I was going to spend on anchor bolts. The beauty of the plywood design is lots of glue and staples and it appears just screws and glue to hold the tops on.

http://www.homedepot.com/p/GRK-Faste...1#.UqeDXF_Tl9A (wfs)
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Last edited by Mike Gin : 12-10-2013 at 02:11 PM.
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Old 12-10-2013, 02:24 PM   #20
Mike Hollister
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Re: Need advice for jerk blocks getting to much bounce

So w/ those screws you don't have to drill pilot holes?
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