Building a glute ham bench

[cj7jeep81]

I'm planning on building a glute ham bench to add to my home gym. I've been wanting one for a while since I tend to have lower back issues (lately made worse with squats). I'm working on my squat form, but I've had back issues before, so think this would help. I priced a few, and am hoping I can build one for around $100 (already have a welder and tools, so no cost there). Here's the design I've come up with so far. Thinking I might need to angle the bars in the front as I'm not sure if they'll be in the way. The pad is 18" wide and 8" tall in the center (6" plywood half circles, then 2" of foam which I read somewhere else).

Anybody have any critiques or suggesstions? Changing now is easy, and would rather make changes before I start cutting metal. The frame is going to be made from 2"x2"x.120" steel tubing. The sleeved parts will either be 2.5"x2.5"x.25" or 2.5"x2.5"x.188" steel. Not sure what size will fit better and allow it to slide without too much resistence, but without too much slop. I'll drill a bunch of holes for adjustment, and am just planning on using implement pins or something to lock in place.

[muddy]

The elite fts guys swear by angling the pad down a little, so it dips towards the handles. And yeah, I'd angle the handles out.

You might as well put on some hooks for bands on the front cross foot, while the welder guy is handy.

If you are tall and plan on doing back extensions on the thing (these : http://media.crossfit.com/cf-video/CrossFit_GHD.wmv ), be sure to measure the length accordingly and drill holes far enough down so the foot stand can be far enough away. Many commercial ones don't fit taller people well for back extensions.

To prevent the slop you mentioned, you could do this: go ahead and use the pin to lock it in place. However, you could add in on both sides a knob that you screw in. The threaded stud doesn't actually do anything other than apply lateral pressure, to prevent sideways movement. You could put this both on the assembly for the peg to position the length of the foot stand, as well as one the assembly that determines the vertical height for the rollers for the feet. (The Elite FTS GHDs are built this way, and it's nice.)


p.s. -- That's very cool you're going to build one! I hope you have the time to post some photos/videos of the results when you're finished!

[cj7jeep81]

I'm the welder, so no problem adding stuff now, or later. I'm just going to spray paint, so no trouble to grind the paint off and modify, but would rather not. I'll add some hooks for bands, that's a good idea.

I'll also see if I can figure out a way to make the foot plate adjustable. As for the knob to tighten, is what you're saying basically using a large set screw? That would probably work fine, as I doubt there will be much slop.

I measured myself to make sure it would be long enough, but did all my measurements based on having the bad being about mid-thigh. Watching that video it looks like I'll also want to be able to put it closer to my belly, which would definitely increase the length. I think I factored enough play in to handle that, but I'll re-measure and make sure. That's something that would be kinda tricky to change later without a lot of re-work.

I really wish I had access to one of these machines. Would make it easier to determine some of the dimensions (like distance between top and bottom rollers on the back), but I think its pretty close. I just plan to tack weld it all together, and test it out before final welding.

[lovestolift]

As for gaining access to one of these, you could do this: Most gyms offer a free workout. Simply go and say you are interested in trying it out. Bring a tape measure.

BTW, It looks like a good design. I am all for DIY equipment. Here's two sites with a few ideas:http://www.geocities.com/fightraining/ and http://www.angelfire.com/ny5/shenandoah/Grunt/grunt.html

Good luck.

[muddy]

I'll also see if I can figure out a way to make the foot plate adjustable. As for the knob to tighten, is what you're saying basically using a large set screw? That would probably work fine, as I doubt there will be much slop.

Yep exactly.

I really wish I had access to one of these machines. Would make it easier to determine some of the dimensions (like distance between top and bottom rollers on the back), but I think its pretty close. I just plan to tack weld it all together, and test it out before final welding.

I have access to a GHD, so if you want any measurements, just list out what you're interested in, and I can get that later tonight.

[cj7jeep81]

The only gym around here is some chain type fitness place in a strip mall. I've never really looked, but looks like mostly cardio stuff. There is a YMCA in town though, and I know a guy with a membership so I'll ask him if they have any there. If not, I should be able to work out the kinks before final welding. And the best part about working with metal, if I cut it too short, I can fix it.

One change I think I'll make is to move the front pillar (that the pad rests on) further forward another 6 inches or so. That's really limiting the length I can go. If it feels too tippy like that, I can just weld some extensions onto the front cross foot.

The "new post is there to look at before you post" feature is pretty cool.

Yeah, if you could take some measurements that would be great. Let me see if I can modify my drawing to include spots for measurements, and I'll post. If not, I'll try to explain what I'm looking for.

[cj7jeep81]

Well looks like our wonderful Internet filter is now not going to allow photobucket while I'm at work. I can post my marked up drawing later, but what I'm looking for is the distance between the two foot roller pads (center to center of the pegs is fine). The distance between the rear pillar and the foot plate (if that makes sense). The dimensions of the pad. I made it 12"x18"x8" high. Overall height from floor to the top of the pad. And finally the overall height from the floor to the top of the rear pillar. I wasn't sure if it would ever be advantageous to be able to adjust the foot plate higher than the pad (doubt it as I'd think you'd be more inclined to do a header to the floor), but figured it would be easy to do in case I ever needed to.

Make sense? And yeah, I'll definitely document this with cut dimensions and build steps. Really, it will be very simple to build. Planning on having bolts to hold the floor cross pieces to the frame so I can remove them to fit it in my basement. Rest would be welded.

[muddy]

Distance between roller pad axles: 8"

Roller pad diameter: 4"

Rear pillar to foot plate (from the trailing edge of the rear pillar): 6.5"

Pad: 14" base with an 8" radius semi-circle, 21.75" wide

Floor to top of pad: 40"

Floor to top of rear pillar: 49"

Foot plate: 20" width x 18" height, bottom edge is 30.5" from floor

Bottom roller axle at minimum position is 31.5" from floor; at max position is 38.25" from floor, adjusts to 7 positions in that range

Band pegs are 21" forward of the middle pad position

[cj7jeep81]

you rock, thanks!