Overhead Workshop Crane - H Beam Trolley Design

What you describe is an underhung bridge crane. You might be able to buy trolleys, to fit your existing beams, to use as end trucks. These connections need several bolts at each end to resist crabbing. I don't know of one to run on top of the bridge in the size you want, but look at the second link, below.

Start looking here.

Or here.

A web search trolleys and hoists will find many suppliers.

sorry for stepping on your toes. g.a.

I beam crane trucks

Hoists & Cranes | Trolleys-Manual & Electric Powered | I Beam ..

thanks to all so far the links are great info. looks like the thing i am after is an end push truck or end trolley. maybe i can use two trolleys with a cross beam 6ft between them but i have to look into that. maybe make a copy of the ones linked to? wheels may be the bigest problem but maybe can turn them and fit needle bearings. gs

Get your existing structure certified to handle the added load of lifting and moving these boats! This will allow you to spend your money wisely in several ways. You will not waste money by buying oversized trolleys for your superstructure. You will not attempt to move boats heavier than your crane and superstructure can safely support.

yes good advise. it is only the outboards and maybe a car engine at times. structure is not yet built so plenty of scope, to be honest i would rather oversize for a better margin without going ott.

Is this in a commercial shop? If so you may also fall under one of many legal sanctions that cover over head cranes and hoist. Be careful to be sure what ever you do it is certified. This means all of the attachment points and materials. OSHA and others take a dim view on lifting devices that are not certified.

First, you need to specify the maximum weight that might be lifted. Each of the 13' beams must be designed to support at its midpoint the load plus the hoist plus half the weight of the cross beam, including two of the trolleys. There's more, but that's a start....

Max weight 500lb more often 250-300lb (30hp - 120hp 4 stroke outboard) each vertical support is a 10x6 beam on a 1/2" thick plate on a concrete strip foundation 30" x 12" (I know I poured it so I don't see any vertical trust problems.

can you put a track on top of the existing beams and have two rollers at both ends of your bridge beam ? you will need to have an end plate to support the rollers, and you will need to check your existing concrete floor strength , the load carrying capacity of your beams exisitng beams , and then calculate what size beam to run across them alternately you could weld a U shaped channel upside down on top of your existing beams ( say 75 x 35 mm or 100 x 50 mm ) and then use rubber coated castor wheels on each end of your bridge beam.

Having spent 33 years in this Field my suggestions are as under:-

1.What is the size of existing I beams are they capable of taking 250 lbs load?.

2.Are you from U.S? In that case you may approach local dealers of Harrington, C0lumbus Mackminon (C.M). Or any other good mfr.

3.Please inform them that trolley should be suitable for existing beam.You may have to adjust the trolley to suit your I beam but adjustment should be possible.

4.Do you wish to go for manual chain pulley block with pull push trolleys or chain electric hoist with pull push trolley.It depends on frequency of use of the equipment.If you select manual chain pulley block then please ensure it is American make or you may get Chinese make which may result in failures.Chinese CPB are dirt cheap but risky.

5.Before going ahead please check feasibility of installing above system for dimensions. Please check ceiling ht. headroom (ht.occupied by crane, Trolley, CPB) ht.of the engine,sling ht.etc. This will avoid last moment problems.

The others have made some very valid points.

Regardless if this is for a commercial shop or an installation in your home home, you really should hire a Structural Engineer to properly design the crane rail beams, the trolleys, the traveling cross-beam and appurtenances, the supporting columns and the concrete footing.

Also, if you install this without a building permit you may be in violation of your local and state building codes......it's a serious LIFE-SAFETY ISSUE.

Last thing you want is the assembly come crashing down on you, crushing you together with the boat, and the boat/car motor. Over the past 35 years of engineering I've seen a handful of these DIY overhead cranes crumple because they were not certified or designed by a PE, that have resulted in serious injury and property damage.

And yes, I do perform Forensic Engineering Evaluations of failed structures, and their causes, and am a Expert Witness in court proceedings.

Thanks for all the great input. On this Tuesday I am meeting with a hoist engineer to go over the plans. I will let you all know the result. G

One of the problems you may have is crabbing as the smaller beam moves. This can result in jerky potentially dangerous motion. To overcome this have a motorised drive at one end with a 6ft drive shaft to wheels at the other end. Go for rubber tyres on the drive wheels and arrange the beam over the top of the side beams to avoid loss of height. Gantry cranes use a similar system and with a worm drive box you will get good control.

i think you can put the trollies on top the crane girders, but you will need two trollies per side. turn the trollies upside down on the girder. space the trollies [trucks] at a reasonable distance apart. design your bridge so it intersects the two trollies. both connections must be square and heavily reinforced to prevent racking. you can put the trolley beam on top of the trucks if you have the head room.

i recommend using trollies that are wider than the girders to prevent binding.

You might want to search Global Spec for trolleys.