|
-
11-20-2008, 08:05 AM #31
-
11-20-2008, 08:09 AM #32
-
-
11-20-2008, 08:15 AM #33
-
11-20-2008, 08:44 AM #34
Im not an architect nor engineer but I see some issues going on. I like the attempt but see some need for improvement.
You got a couple problems going on here. Lag bolts are designed more for downard or sheer strength, not what your using them for. Drywall screws? Hell no. It takes little effort to snap a drywall screw. Try adding good old nuts and bolts or quality purpose accounted screws. Would also be a good idea to use metal sleeves for the bolts to pass through.
Another issue, your didnt box in the top, WTF (see C) I guess it would be fine, as long as noone ever touches must less rests against the front left or right support.
Your barbell pins are at an angle, not only at an angle but run with the wood grain, what do you expect to happen after constantly dropping the weight on the pins, get lazy leave the weight on the bar, time and time again, dont think it wont happen?
The knurl in the bar will eat at the wood over time, have you ever seen a metal bench's bar rests? It also appears over time it would eat right into your bar rest pins, not good.
I think you had the right idea doubling up the wood, maybe its cheapr than a 4X4 I dont know, either way, Id rather see someone use the design below. Measure the squat bar rest position (A) and bench bar rest position )B) for you or with some error and use doubled wood/4X4's as upright supports. Add metal plates on top, to cap (E) the bar rests to encourage longevity. It wouldnt get any stronger than this,unless you went with steel. I would also add wood to either side of the bar rest positions (D), not only for structural support but as an added safety should the adjustable safety bars fail. Dont know what in the hell your using as safety bars but it does not appear big enough to support much if any weight. Remember your not dealing with dead weight but weight that is falling with momentum, should you fail on a rep.
This image is exaggerated, in reality, I would double the corners as well or use 4X4's.
This is my opinion, use at your own risk, when in doubt, keep saving and do it the right way.Last edited by need2eat; 11-20-2008 at 09:15 AM.
"People are bastard covered bastards, with bastard fillings"
-
11-20-2008, 09:22 AM #35
Well I'll elaborate some on why I built it this way and see if it makes more sense, you've got some good suggestions though.
Where the lag bolts are at it's mainly just tying the two sides together. The bolts are screwed into each leg base katty-corner to each other to help keep either of the two "ends" of the rack from shifting or rotating. This may not be a lag bolts intent but the frame does not move at all so it's working. If you're worried about the frame moving, add some 45 degree kicker boards going from each side tying into the back board along the bottom similar to what's going on between the legs on the verticals. That will stiffen it up more than any other bolt type will. As for the drywal screws...they don't need to be that strong. Their only purpose is to help hold the leg boards together, force from a vertical weight dropping is not going to stress them much at all. The way the double leg boards are screwed together top and bottom they can't really ever come apart.
The top isn't boxed so it can accept a chin bar If you want the top reinforced and keep the bar, go with the kicker boards across the top like I mentioned for the base. (see the drawing below). As it sits, leaning on this thing does not flex it much...it rocks less than alot of steel cages. This thing is heavy! What I may do later is put a 2x4 anchored to the floor joist above it and use a metal "L" bracket and screw it to the board. If you go with the pullup bar this would probably be wise to help reduce any rocking.
I don't know what you are referring to when you say they run "at an angle"...they fit straight thru the boards. The pins fit snug in the holes, using the washer and cap to screw it thru the legs there is no movement when tightened. Over many years of abuse I'm sure they will loosen up some. I don't think you give wood enough credit on its compressive strength, that is 3" of heavy timber each side.. If it gets too bad the option is to drill the hole slightly bigger and go with a metal pipe sleeve in the holes that are failing.
I'm sure this will take MANY years. If it' starts eating the wood away there are ways to jerry-rig some sheet metal or something over the legs to prevent this.
[/QUOTE]
This design looks sturdy but not very adjustable. To each their own, as long as it works and you're happy As I progress I'll see how this rack holds up and what should be done differently. I'm sure someone who squats 600 and benches 400 will exploit any issues quicker than I will.Last edited by gipper51; 11-20-2008 at 10:00 AM.
-
11-20-2008, 09:52 AM #36
[QUOTE=need2eat;248245391]Im not an architect nor engineer but I see some issues going on. I like the attempt but see some need for improvement.
QUOTE]
I'm an engineer and I'd stamp those drawings. Wood is a lot stronger than you'd think especially in compression and I'm pretty sure he's got several screws so them shearing is slim to none.Toxic Masculinity
-
-
11-20-2008, 12:18 PM #37
Just have to agree to disagree, you posted the best concept thus far, Ill give you that.
I was mistaken about the pins or hole angle, for the barbell rests. Other than that, think Im gonna have to stick with what I wrote, as far as, my two cents, right or wrong.
Just remember, expansion and contraction, over time things will get loose on you.
Have no interest in turning this into a discussion, but I dont want you hurt either, so if I dont reply further, youll understand.
Good luck
Engineers can be wrong too. My concern isnt compression, its basic leverage.Last edited by need2eat; 11-20-2008 at 12:32 PM.
"People are bastard covered bastards, with bastard fillings"
-
11-20-2008, 12:28 PM #38
-
11-20-2008, 12:33 PM #39
-
11-20-2008, 12:35 PM #40
-
-
11-20-2008, 12:48 PM #41
[QUOTE=need2eat;248348371]Just have to agree to disagree, you posted the best concept thus far, Ill give you that.
I was mistaken about the pins or hole angle, for the barbell rests. Other than that, think Im gonna have to stick with what I wrote, as far as, my two cents, right or wrong.
Just remember, expansion and contraction, over time things will get loose on you.
Have no interest in turning this into a discussion, but I dont want you hurt either, so if I dont reply further, youll understand.
Good luck
QUOTE]
Appreciate the concern and I did take all your comments seriously. I'm sure the rack can be improved yet and safety should be priority #1 for something like this...that's the whole purpose of the machine.
Your comments did get me thinking about bracing the top a little better. Especially if I add the chin bar it will help stiffen things up even more. Actually with the top anchored to the floor joists I dont think it would move at all.
And actually when I was looking at the concept you had drawn it got me thinking about how it could work with more adjustments. I think the trick would be divising a way to have the rack legs be removable segments that you could replace with various length pieces for height adjustments. Could attach to the main support leg with a thru bolt or strap of some kind...just a thought.
-
11-20-2008, 01:06 PM #42
-
11-20-2008, 01:14 PM #43
-
11-20-2008, 02:06 PM #44
Adding the kickers at the top won't make a difference in how much weight it will stop, the purpose of those is just to reduce rocking on the frame. I would add them if you intend to add the chining bar as it will stiffen the whole frame up even more. In fact if you are a big lifter who can do chins with added weight I would even bump those top boards up to 2x8 and use 4 screws at each corner just to be safe. The ideal thing is if you have a way to add wood braces up to your ceiling stucture ...then the frame wouldn't move at all.
I honestly don't know how much weight the frame will take before it fails. In straight compression (downward force) a wood post will hold a **** load of PSI before it fails. I've seen whole upper floors of houses held up with just a few 4x4 posts (not good but it holds). Having the spotter bars actually crack thru the wood posts from a barbell falling would take more weight than most mortals can lift IMHO. If the frame were to fail it would be more likely from a defect in the wood such as a split or knot or just plain poor construction techniques. Good carpentry skills here will be just as important as having good lumber. This is also where buying the better grades of lumber will make the frame stronger. If I had had enough weights I would load up 500lbs and drop it on the rack to see if it holds but I don't As it stands just from what knowledge I have of timber construction in buildings and what they can hold I have no doubts this frame will hold up to some very heavy lifting if you build it well.Last edited by gipper51; 11-20-2008 at 02:08 PM.
-
-
11-20-2008, 09:05 PM #45
....well bridges are made out of wood and trucks drive over them.....but a bigger truck could drive over a metal bridge.
...i think people cringe wehn they see (or hear) about wooden racks....but the one you built seems to be the best of the ones I have seen. Good luck with it.[]---[] Equipment Crew Member No. 12
https://www.youtube.com/user/solvedphysicsproblem
117 videos showing the solutions to all highschool physics problems that could possibly come up.
-
11-21-2008, 04:10 AM #46
-
11-21-2008, 10:29 AM #47
-
11-21-2008, 11:34 AM #48
I'm not a regular poster here but do lurk alot. This year I decided to trash the gym membership and build a home gym in the basement. A power rack was in order but cash was tight so I built my own. I use AutoCAD daily for my job so I drew up a plan and thought it may be helpful for some of you here. While I have not officially "tested" the rack by purposely dropping a huge ass weight on it, I have no doubts the frame will take a serious beating...it's alot of lumber! It's more solid than some steel cages I've seen.
Everything to build this cost me $115 in materials you can buy at Lowes or Home Depot. It's mostly 2x6 boards with some 3/4" diameter plumbing pipe and fittings used for the rack pins and spotter bars. Word of advice: buy the better grade lumber for the vertical legs at the very minimum...sorting thru the cheap **** to find 8 decently straight board may take all day. Also the job does require some power tools. You will need a powerful corded drill with a spade or auger bit and ideally a bench mounted table saw for straight cuts. The holes to cut in the vertical legs is the most time consuming part of the project. Here's where you need the big corded drill as it will tear a cordless drill up in no time using the big spade bits. Overall expect about 3-6 hours of time depending on your construction skills. If you got any questions let me know, I'll be happy to help.
Below is a link to the plans as high resolution JPGS, this site won't let me post files big enough to read. The drawings are to scale if you print the page at full size of 11x17
EDIT:_____________________________________________ _____________
Due to some concern over the rigidity of the frame top, I have updated the plans with a beefier top section. The boards holding the pullup bar are now 2x8 and there is another 2x4 member connecting the front ends adding stability. For the most stability, you should brace the top sections to your ceiling structure with some additional 2x4s or whatever you have laying around. This additional lumber will add a few more $$ to the overall price and the price I listed when I made mine did not include the top chinning bar. Figure on spending $120-$140 as the updated drawings show. The images in my first post have been updated, go see those links for the updates. Thanks.
-
-
11-21-2008, 01:46 PM #49
-
12-06-2008, 12:43 PM #50
-
03-19-2012, 12:32 AM #51
-
03-19-2012, 01:18 AM #52
-
-
03-19-2012, 06:57 AM #53
- Join Date: Feb 2011
- Location: Los Banos, California, United States
- Posts: 733
- Rep Power: 1952
http://youtu.be/YcwWoBcAxME
You might like this video from Carlos DeJesus. I'm not a big fan of wood, but I am a fan of all the old school 1" plates in the video. Carlos has a very good interview that's on the web somewhere with Tom Venuto
-
03-19-2012, 08:10 AM #54
That is a cool video. Almost everything in Carlos' gym is made from wood. He gives a tour of his gym with either he or Susan often demoing a piece of equipment. But when he gets to the power rack though, he says "Everybody knows what a saftey cage is. I can't compromise with this - it does have to be made out of steel."
▪█─────█▪ Equipment Crew #35
-!!!---!!!- No Excuses Homemade Equipment Crew #14
-
03-19-2012, 08:30 AM #55
- Join Date: Aug 2011
- Location: Massachusetts, United States
- Age: 43
- Posts: 673
- Rep Power: 526
Thank you for that wood gym video. Really just inspired me. We have a shop full of tools and I have nothing but free time lately. I like the seated calf raise machine. I been just resting dumbbells on my knees and doing them. Half this stuff can be made with just 2x4s and for cheap as hell. Time to sharpen up my wood working skills lol
-
03-19-2012, 08:36 AM #56
-
-
03-19-2012, 09:00 AM #57
-
03-19-2012, 09:47 AM #58
- Join Date: Feb 2011
- Location: Los Banos, California, United States
- Posts: 733
- Rep Power: 1952
http://youtu.be/f63LvuEKZ0E
This one has Carlos DeJesus's homemade gym equipment from the 80's Complete with MJ / Survivor music
-
03-20-2012, 07:56 AM #59
-
06-29-2012, 05:33 PM #60"It's common knowledge man. You should only use Indica for bulking, Sativa for cutting."
"Who needs proper form? He was too busy setting PR's! Forget proper form, acquire PR's!"
"It's STILL your MUTHAFU$KIN set!!!!"
“Everybody wants to be a bodybuilder, but nobody wants to lift no heavy-ass weights.”
Bookmarks