07-27-2012, 03:10 PM
Greg
I was looking at your system on SFT (I think, been checking out a lot of forums lately) and it is nicely done but you have a higher ceiling height than I do.
Headroom is one of the most important factors here, with only an 8 foot ceiling height I am doing everything I can to reduce this.
Yes the plan is to make a "Barn Door Style Rail" from 4x3x1/4 HSS Tubing. I would like to go with the Richards-Wilcox 888 Tracking, but the price is very high on that stuff, Lists for $56.50 USD per Foot! Plus I have to go to the states to get it as there is no distributor for it in Canada.
I have been talking to a crane engineer who is reviewing my plans and has advised me that the "steel" portion of the crane is good for 5000 lbs. using the twin cross beams on the bridge or 2500 using a single cross beam, with standard safety margins and the longitudinal rails can be mounted with the mounting brackets/bolts etal 40 inches apart, providing the superstructure is capable of handling the weight, so we are working on the load capacity of the joists now to see if they will handle the weight.
I am planning on the dual cross member bridge as it allows me to lift the hook point up about 3" closer to the ceiling.
My plan is to mount the rails to each joist that way the load is spread more evenly over the entire joist system, not just spot loaded every 3 feet. The trolleys were made as long as possible with the bearings spread out as much as possible to get the best tracking and minimal skewing.
We have also revised the trolleys to use Cam Follower Bearing Assemblies, mounted in a staggered pattern. The Cam followers are about $ 10.00 more than the 6205 Bearings that I first planned, but they simplify the mounting as I do not have to machine up the axles and press them into the plates, instead they are held on with fine thread Nylocks.
Thanks for your input.
Walter
I was looking at your system on SFT (I think, been checking out a lot of forums lately) and it is nicely done but you have a higher ceiling height than I do.
Headroom is one of the most important factors here, with only an 8 foot ceiling height I am doing everything I can to reduce this.
Yes the plan is to make a "Barn Door Style Rail" from 4x3x1/4 HSS Tubing. I would like to go with the Richards-Wilcox 888 Tracking, but the price is very high on that stuff, Lists for $56.50 USD per Foot! Plus I have to go to the states to get it as there is no distributor for it in Canada.
I have been talking to a crane engineer who is reviewing my plans and has advised me that the "steel" portion of the crane is good for 5000 lbs. using the twin cross beams on the bridge or 2500 using a single cross beam, with standard safety margins and the longitudinal rails can be mounted with the mounting brackets/bolts etal 40 inches apart, providing the superstructure is capable of handling the weight, so we are working on the load capacity of the joists now to see if they will handle the weight.
I am planning on the dual cross member bridge as it allows me to lift the hook point up about 3" closer to the ceiling.
My plan is to mount the rails to each joist that way the load is spread more evenly over the entire joist system, not just spot loaded every 3 feet. The trolleys were made as long as possible with the bearings spread out as much as possible to get the best tracking and minimal skewing.
We have also revised the trolleys to use Cam Follower Bearing Assemblies, mounted in a staggered pattern. The Cam followers are about $ 10.00 more than the 6205 Bearings that I first planned, but they simplify the mounting as I do not have to machine up the axles and press them into the plates, instead they are held on with fine thread Nylocks.
Thanks for your input.
Walter
starlight_tools, proud to be a member of Metalworking Forum since Apr 2012.