Author Topic: Can a 5"x1 3/4" joist support a WM18  (Read 1642 times)

Offline picclock

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Can a 5"x1 3/4" joist support a WM18
« on: January 31, 2018, 11:46:27 AM »
Considering a larger mill but will have to install myself. Weight all up is 160 kgs but I'm hoping to hoist it up in bits using the joist and a pulley or similar. How much weight can a 5" x1 3/4" joist take ? about 3-4ft from the wall. Any idea ???

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picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline John Rudd

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #1 on: January 31, 2018, 01:04:22 PM »
Can you double up on the 1 3/4" thickness?

You might have a fighting chance then.....
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Location:  Backworth Newcastle

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Offline hermetic

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #2 on: January 31, 2018, 01:55:19 PM »
If you can put a prop in to reduce the span of the joist, it will be fine, can you post a sketch of the set up?

Offline picclock

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #3 on: January 31, 2018, 03:29:34 PM »
Hi hermetic

Sketch as requested. The garage was built over 3 different eras. This is the weakest section (and the newest), others have massive joists.

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picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline Lew_Merrick_PE

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #4 on: January 31, 2018, 04:02:59 PM »
Considering a larger mill but will have to install myself. Weight all up is 160 kgs but I'm hoping to hoist it up in bits using the joist and a pulley or similar. How much weight can a 5" x1 3/4" joist take ? about 3-4ft from the wall. Any idea ???
Picloc -- The stress you will need to worry about is the extreme fibre stress in ths joist.  Assuming that you will hang the pulleu some distance below the Joist's horizontal centerline, the thing will be controlled by the Area Moment of Inertia.  That is (for the beam itself) b*h*12 or (1.75)*(5^3)/12 = 15.625 in^4.  If the axis of your pulley is located (say) 5 inches (below assumed) from your Joist's horizontal centerline, then add rA (64 * 7.5 = 480 in^4) to the 15.625 in^4 (for 495.625 in^4 total).  As I recall, your Pulleu will be located 1 m (call it 40 inches) from the "support" for the Joist.  Thus, yopur "applied bending moment" is (160 kg)*(2.205 lb/kg)*(40 inches = 14,110 lb-in).  Your fiber stress will be S = mc/I = (14,410 lb-in)*(8 inches)/495.625 in^4) = 233 lb/in.  Most structural timbers here in the U.S. have an allowable fibre stress in the 1600 lb/in range.  Does this help?
« Last Edit: February 01, 2018, 12:10:56 AM by Lew_Merrick_PE »

Offline awemawson

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #5 on: January 31, 2018, 04:36:31 PM »
When I unloaded my Bridgeport at my last place, I reversed the trailer into the workshop and erected Acrow Props either side of the trailer pressing up onto the relevant joist above thus minimising the span of the beam.

OK they were 9" x 2" joists but the span without the acrow props would have been 20 foot !
Andrew Mawson
East Sussex

Offline chipenter

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #6 on: February 01, 2018, 03:15:03 AM »
You could also connect the rafter to the joist halving the load .
Jeff

Offline RussellT

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #7 on: February 01, 2018, 06:05:36 AM »
You could also put in beam running across several joists to spread the load.

Russell

Offline picclock

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #8 on: February 01, 2018, 09:30:28 AM »
Thanks to all for the ideas.

Acrows sound wonderful, never thought of using them like that. I have some 3" box section which I can place in between the beam and the acrows, that way the stress is taken by the acrows and steel box section with the joist just giving lateral stability with minimal load on it. Acrows look like they are good for a ton so it should be comfortably rated.

I'm also considering making a stand for it with castors on to simplify relocation if needed for cleaning, maintenance etc. Is this a bad idea with a mill?

Best Regards

picclock

Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline awemawson

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #9 on: February 01, 2018, 12:12:13 PM »
Just make sure that the joist and box section cannot pivot forward or back by having them fixed to several other joists by a tie timber. In my case there was an OSB floor above fixed to all the joists very effectively anchoring the one I was using.
Andrew Mawson
East Sussex

Offline hermetic

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #10 on: February 01, 2018, 04:19:05 PM »
Yup! they all got in before I got back! if you prop the joist as close as possible to the lift point, with a fixed prop that can't fall out, you will be fine. Lift it half an inch and let it sit for a few minutes to test the rig, then go ahead.

Offline WeldingRod

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #11 on: February 03, 2018, 09:40:55 PM »
Yup! they all got in before I got back! if you prop the joist as close as possible to the lift point, with a fixed prop that can't fall out, you will be fine. Lift it half an inch and let it sit for a few minutes to test the rig, then go ahead.
I tied my garage ceiling to the roof to create a big truss structure.   My joists are bigger, and doubled and cross connected at my lift point, with the resulting safe working load well in excess of a ton.  I'm a mechanica l engineer and have to move stuff up to 80 tons at work... not going to have my home stuff fail! No siree!

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Offline RobWilson

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #12 on: February 04, 2018, 02:58:01 PM »
 WTF!  a hole  160kg   :lol: :lol: :lol: :lol:,  that's an easy lift for two blokes.Well, what I mean are two men who actually do real  work, not your average IT chap.

Offline Meldonmech

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #13 on: February 06, 2018, 05:25:15 AM »

 Nice one Rob, I like it.

                                             Cheers ha ha !

                                                                  David

Offline PekkaNF

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #14 on: February 06, 2018, 06:34:57 AM »
WTF!  a hole  160kg   :lol: :lol: :lol: :lol:,  that's an easy lift for two blokes.Well, what I mean are two men who actually do real  work, not your average IT chap.

I once bought a miniature capstan althe that was missing the whole capstan stuff...Seller told me it weight less that 400 kg. I Got transportation close to my home and had it loaded onto my trailer (500 kg capacity nominal). Had three friends waiting home and I had rigged platform and all ready. "Only" thing we had to do was to lift the bugger few centimetres, my daugter would pull the trailer out and let it sit a little lower...it would not lift! Four could lift each end but to have it lifed clear was deemed too dangerous.

I had one guy to visit with truck/lift. He fits large windows, the boom had a scale. Scale shows 960 kg! A small wonder it felt a bit too heavy. And when it is a lathe shape object, lift has to very secure. No-one wants that shape of things to tilt.

Pekka

Offline krv3000

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Re: Can a 5"x1 3/4" joist support a WM18
« Reply #15 on: February 06, 2018, 04:18:16 PM »
well I have a friend lol yes its hard to believe lol  when john got his lath him and mick was trying to put it in place a bit like the chuckle brothers me friend told them to get out of the way  and he  lifted it in place mick and john just    :jaw: :jaw: