Any structural engineers in here?

[rebar]

Pitbull strapless restraint.. Any structural engineers in here?

I have a 4" x 2" x 1/8" aluminum I beam I need to mount 4 supports from..

The I beam is 8' 6" long and I'm considering drilling eight 3/8" holes in the center of the middle web, not the outside flange. Two holes 4" apart, every 22" about..

Will this significantly weaken the I beam enough where I should weld the supports on? Or promote a stress crack to begin? Could welding make the I beam weaker?

Thanks!

 

[twistedmax]

whats the applacation? Id be more concerned with having it weldded properly. to much heat no good,and it could also warp the I Beam, if you have somthing bigger that you can clamp it to while you weld it and let it cool. I dont think the holes will matter much. Im not an engineneer but I do have to redo their work on a daily basis, Im building elevators now and you would be amazed!

 

[[email protected]]

Well, if you want an engineer's answer, you'll need to provide a shit load more information to plug into some formulas. :biglaugh:

 

[rebar]

Well, if you want an engineer's answer, you'll need to provide a shit load more information to plug into some formulas. :biglaugh:

Its 6061 t6 aluminum. 3/8 Holes will be at 17" 21" 39" 45" for one bike. And 59" 63" 81" and 85" for the other.. Two I joists holding 1000 lbs of bikes.. Already with a big hole in the center.

The stands fall between the I joists, so I need to mount/weld in 4 ladder rungs so to speak because the plywood alone isn't strong enough. And either tap a 3/8 16 hole, or weld in hex couplers weld nuts supporting the plywood to except the four mounting bolts. I haven't decided exactly which material, But I do know the mounting area needs to withstand as much downward force as up pulling force unlike tie downs which only pull.

 

[wildweasel_pt]

Thats high quality trailer dude... Getting that type alloy for that is overkill or at least bad usage of such grade material

 

[rebar]

Thanks, yes featherlite trailers are one of the better brands, and I thought they all came with aluminum decks.. But mine has Marine grade plywood which I simply dont trust. I dont want to get to my camp ground and find both bikes in a pile in the front of the trailer with a 4x8 piece of plywood attached to both rear axles. :biglaugh:

I might be able to get by with only 4 holes per I beam if I alternate direction of the angle brackets.

 

[88vmx12]

I have a 4" x 2" x 1/8" aluminum I beam I need to mount 4 supports from..

The I beam is 8' 6" long and I'm considering drilling eight 3/8" holes in the center of the middle web, not the outside flange. Two holes 4" apart, every 22" about..

Will this significantly weaken the I beam enough where I should weld the supports on? Or promote a stress crack to begin? Could welding make the I beam weaker?

Thanks!

Rebar,

I wish I was there to look at it in person. ok first of all (generally) aluminum has a higher chance of splitting from a hole or a corner than steel provided it has a high chance of fatigue. Welding also promotes a hard spot in materials. An arc strike in materials can cause what they call a spider web fracture. There are a lot of bad things that can happen from mis installation of materials. If you are planning on drilling holes in the middle of the vertical web that is in the existing supports in the floor of the trailer. It would not bother me one bit. The place for fatigue will not be in the center of the member , so no worries unk:. Now the bad thing is if you are bolting it and use regular steel bolts then it will cause electrolosis and eventually eat away the aluminum. So then you can go to a stainless steel bolt which will curb the problem. Now you get into where you will need to use an anti seize coating (copper based is good enough)for the threads of the bolts, it will keep the threads from galding. You can get it at the parts store. I hope I have helped you out , if not in writing you are free to give me a call 208-280-0315 , I used to be a fabricator for a living :clapping:

 

[rebar]

Rebar,

Welding promotes a hard spot in materials. An arc strike in materials can cause what they call a spider web fracture. There are a lot of bad things that can happen from mis installation of materials. If you are planning on drilling holes in the middle of the vertical web that is in the existing supports in the floor of the trailer. It would not bother me one bit. The place for fatigue will not be in the center of the member , so no worries unk:. So then you can go to a stainless steel bolt. Now you get into where you will need to use an anti seize coating (copper based is good enough)for the threads of the bolts, it will keep the threads from galding. :clapping:

Yes that helped allot 88vmx12.. Sounds like drilling eight 3/8" holes in the center web is a better choice over welding. And use stainless bolts to mount The cross pieces. From the fact featherlite drilled a 1" conduit hole in the center of these I beams.. Drilling more 3/8" shouldn't be a issue.

Should these added cross pieces be fabricated from 6061? Because I need to thread 3/8 bolts either into it or add weld nuts or hex couplers to thread into?

Thanks!

 

[Redbone]

I don't know if these would help in your setup but they look like a viable option: http://www.discountramps.com/cargo-quick-nuts.htm

 

[rebar]

I don't know if these would help in your setup but they look like a viable option: http://www.discountramps.com/cargo-quick-nuts.htm

Spendy.. But nice for a truck bed. I'm not sure if those would come in handy yet, thanks.

 

[Barry barker]

Not to but in, BUT, What if you used 10ga sheet metal or marine grade 3/4 " plywood as a backer plate? Through bolt the stands to it using fender washers and lock nuts. Make it full length to distribute the load over as large an area as you can. If you are really concerned about the uplift of the plywood floor, add a few more screws to hold it to the support beams.

Just a thought!

 

[Redbone]

Spendy.. But nice for a truck bed. I'm not sure if those would come in handy yet, thanks.

Yes they are a bit spendy, I looked for an alternative to mount my wheel chock and could not find anything like it.
If anyone knows where I can get these cheaper or a workable alternative solution let me know! (LINK)
I'm going to have 2 chocks in my trailer, one is going to be permanently mounted (setup for my Vmax) and the other will be mounted using these removeable "Quick Nuts" since it would be partially blocking the door when in place (using a '03 FZI demensions).
I'm thinking of mounting a aluminum plate underneath my Vmax chock that extends from one frame rail to another (steel "L" rails, rustproof coated) which I'll glue to the underside of the floor as well as bolting to frame rails. Under the other chock I will be able to mount 2 of the bolts through the frame rail.

 

[88vmx12]

Yes that helped allot 88vmx12.. Sounds like drilling eight 3/8" holes in the center web is a better choice over welding. And use stainless bolts to mount The cross pieces. From the fact featherlite drilled a 1" conduit hole in the center of these I beams.. Drilling more 3/8" shouldn't be a issue.

Should these added cross pieces be fabricated from 6061? Because I need to thread 3/8 bolts either into it or add weld nuts or hex couplers to thread into?

Thanks!

you can make from what you like aluminum or steel. Just remember if you use steel you need to isolate the carbon from the aluminum because of the electrolosis. You can use something as simple as a peice of a bicycle inner tube. I like both materials aluminum and steel. I have been in the same situation as you before with a trailer I had. I used steel angle iron as the cross pieces then tack welded a nut on the underside of one leg of the angle. That leg was flush to the backside of the floor . Then I could drill a hole through the wood floor , the nut would always be in its place and I could easily remove the bolt or tie down when I needed to. The aluminum...... good luck finding a aluminum nut easily to weld onto the angle. The bad thing is aluminum you need to get it so hot to weld and the nut probably wont survive. depending on the space between your floor cross members you could easily get away with 2x2 x 1/8" angle or go to a 3/16 and that would be MUCHO plenty! oh once you have tack welded your nut on the angle you will need to let it cool and then run a tap back through the threads to clean out the threads. There are a ton of other tricks that are way too wordy to type!unk:

G

 

[rebar]

you can make from what you like aluminum or steel. Just remember if you use steel you need to isolate the carbon from the aluminum because of the electrolosis. You can use something as simple as a peice of a bicycle inner tube. I like both materials aluminum and steel. I have been in the same situation as you before with a trailer I had. I used steel angle iron as the cross pieces then tack welded a nut on the underside of one leg of the angle. That leg was flush to the backside of the floor . Then I could drill a hole through the wood floor , the nut would always be in its place and I could easily remove the bolt or tie down when I needed to. The aluminum...... good luck finding a aluminum nut easily to weld onto the angle. The bad thing is aluminum you need to get it so hot to weld and the nut probably wont survive. depending on the space between your floor cross members you could easily get away with 2x2 x 1/8" angle or go to a 3/16 and that would be MUCHO plenty! oh once you have tack welded your nut on the angle you will need to let it cool and then run a tap back through the threads to clean out the threads. There are a ton of other tricks that are way too wordy to type!unk:

G

I get the idea..
And I plan on doing just what you did except add a alum angle bracket which supports the steel angle iron up against the plywood will also extend down to the bottom corner of the I beam to provide just as much pushing down strength as pulling up strength.

Its crystal clear now thanks to the suggestions here.. I will post a few pics when I'm done.

Thanks!

 

[88vmx12]

cool......... Pictures! LOL

 

[rebar]

cool......... Pictures! LOL

:biglaugh:

Finally got around to installing the pitbull.

Plus's..
Wont have to worry about any straps coming loose. Takes maybe 3 minutes to mount your bike. And leaves only four 3/8 holes in the floor when removed. A few screw plugs and it disappears..

 

[ninjaneer]

Good Job!!!

 

[88vmx12]

Rebar, can you say "Over Kill!" ? LOL that will never go anywhere! nice isolation pads by the way. Very good job better than about 90% of the fab shops these days too. An A+!
I love that mount that mounts to the rear axle, where do I get one of those?

G

 

[Redbone]

That should work, nice bit of bracing underneath! I know that it's proven, just seems like their should be more than the pit bull to secure it.:confused2:

 

[rebar]

Rebar, can you say "Over Kill!" ? LOL that will never go anywhere! nice isolation pads by the way. Very good job better than about 90% of the fab shops these days too. An A+!
I love that mount that mounts to the rear axle, where do I get one of those?

G

Yea, I wont have to sweat and worry about if my bikes are strapped down. Isolation pads? 3/16 alum spacer on-top of 3" channel with couplers welded under supported by carved up 8" alum channel. PITA , my hips and knee's are killing me.

The mount is made by Pitbull..

That should work, nice bit of bracing underneath! I know that it's proven, just seems like their should be more than the pit bull to secure it.

I hear ya.. Only way it might let go is in a accident. I'm covered..