Page 2 of 3

Re: My rusty Star Destroyer

Posted: Tue Oct 28, 2014 7:15 am
by rusty
If the cross bracing on the bulkhead is in good shape you will be OK to remove the outer most structure. I would jack the bus up to relieve most of the pressure on the springs. Make sure you get a good weld on the lower frame rail as that is the main frame that carries all the weight. Use stringlines or lasser to make sure all is straight. Try not to weld in one spot to long as the metal will walk and not come back.

Wayne

Re: My rusty Star Destroyer

Posted: Sun Nov 02, 2014 9:42 pm
by sparkplug188
I am working on the same problem on my bus. I jacked up and leveled the bus on 20 ton jack stands in five places, one side at a time: 4th bay bulkhead, drive axle front bulkhead, drive axle rear bulkhead, front of engine cradle, and rear of engine cradle. I temporarily welded two lengths of 2" black gas pipe to the inner frame rail and the roof supports to hold the weight of the roof while the wall was cut out. I also released all of the tension on the drive axle suspension by backing off the four large nuts. When I cut out 20' of the outside frame rail, nothing sprung out of place or went flying. All of the stress was released before I made my first cut. Once the outer frame rail and wall cross braces were replaced, I cut out the temporary gas pipe supports. I welded 12" x 12" x 1/4" steel plates to one end of the black gas pipe and welded the other end to the bottom of the outer frame rail. With the outer frame rail supported, I cut out and replaced the vertical shackle supports, shackle mounts, and shackles one at a time. My 5 jack stands and two gas pipes are all kinds of overkill-- but you can never be too careful cutting out large chunks of load bearing frame.

Re: My rusty Star Destroyer

Posted: Mon Nov 03, 2014 8:51 pm
by tophatperformance
Spark plug do you have any photos I could look at of the work you did? Sounds like your dealing with the same area. Was it recent?
Thanks everyone

Re: My rusty Star Destroyer

Posted: Tue Nov 04, 2014 6:21 pm
by sparkplug188
Sorry, I do not have any pictures except for the rusted out "before" pictures. I have completed the replacement of 20' of outer frame rail, wall cross braces, and one vertical shackle support. I have three more vertical supports and shackles that I haven't touched yet.. At this time, the rear suspension work is on hold. I am working all day every day to get the walls and floor sealed up for winter. When it is 20F in January, I want to be stud framing and wiring the walls in preparation for spray foam insulation.

Here are a couple tips:
Don't bother trying to unscrew the shackle bolts. My 2000 ft/lb 1" impact wrench couldn't break them loose. Wash the bolt heads and nuts off with a plasma cutter set to gouge or oxy-acetylene torch. Use an air hammer to drive the bolts out. I wasn't getting anywhere with a mini-sledge hammer and punch.

If your weld on shackle mounts are nearly rusted through, replace them. Once you start pounding on the shackle bolts, you might find out they are in worse condition than you thought. I bought my replacement weld on shackle mounts from Jefferson Truck Trailer & Bus Repair in Oklahoma City, OK (405) 272-0213. They were not cheap. However, I got what I paid for. I can tell they were cut off of another bus, but they look brand new. I couldn't find a single rust pit anywhere on them.

The welds around the shackles and supporting frame work are critical. Each shackle will be subject to a static load of ~5000lbs and shock loads of several times that. It may be worth beveling and tacking everything together, then hiring a certified welder to weld everything out. If you have the experience needed to make a flawless weld every time, proceed at your own risk.

McMaster Carr has the exact same grade 8 hardware as the bus companies for half the price.

Re: My rusty Star Destroyer

Posted: Tue Nov 04, 2014 7:41 pm
by beltguy
OK, we got this thread fixed and all of the posts are displayed.

Jim

Re: My rusty Star Destroyer

Posted: Sun Nov 09, 2014 3:30 pm
by tophatperformance
Ran into a nightmarish issue today. Started cutting the rust from my front suspension rear bulkhead and realized that's not one big piece of steel plate!!! I think my suspension is going to have to come out to fix it. How does that work? I'm assuming it's sprung tension. Do I just mark the holes and take the bolts out?

Re: My rusty Star Destroyer

Posted: Sun Nov 09, 2014 7:44 pm
by sparkplug188
I recommend taking the tension off of the torsilatics suspension by backing off both of the large adjusting nuts BEFORE unbolting the torsilatics tube from the frame. It may be enough to just let the wheel end hang down onto a lowered jack and support the tube with jack stands, but I wouldn't take any chances. There is no harm in backing off the adjustment nuts so that the arm can slide freely along the threaded push rod. You will need to adjust the ride height once your conversion is done regardless.

I am going to PM you a link to a manual for your bus. Removal procedure is on PDF page 77/1231, section 12-4, push rod (12) and lock nuts (24). There are quite a few steps that can be skipped since you aren't completely removing the torsilastic tube; you just need to free it from the bulkhead on one end.

Edit: I forgot you have a model 10 eagle; the link I sent you is for a model 5. Some things may be slightly different, but the procedure will be similar. If anyone has a PDF manual for the model 10 (or any other models), please send it to me. I would like to add it to my library for reference.

Re: My rusty Star Destroyer

Posted: Mon Nov 10, 2014 8:29 pm
by tophatperformance
Thanks a lot Spark! I'm getting ready to pour some level foundations to support the bus. Can I support the front using the cast piece between the tubes and still get the tubes out? I was thinking about supporting the rear using the suspension bars running from front to back. Putting a jack stand at each end where the mounting points are on both sides of the bus. That would be four stands total in the rear. You think that would be ok?

Re: My rusty Star Destroyer

Posted: Mon Nov 10, 2014 10:01 pm
by sparkplug188
Carefully think about how the weight of the roof is transfered through the framework to the ground before you proceed. The roof pushes down on the walls; the walls push down on the bulkheads; the bulkheads push down on the inner frame rails and torsilastic tubes; the torsilastic tubes push down on the wheels. In other words, you can't support the walls by jacking up the inner frame rails if the bulkheads are cut out. The way I chose to lift my bus to when I was replacing the bulkheads was to support as many structurally sound bulkheads as possible with jack stands. I supported the wall directly above the bulkhead being cut out with 2" gas pipe wedged between the bottom of the outside frame rail and a steel plate on the ground; then welded the pipe in place for extra security.

I am not sure about lifting the cast iron part of the front suspension even if the bulkheads were in good condition. Definately no, if the bulkheads are weak or are being worked on. Those long bars on the rear suspension are hollow tubes. The mounts may be okay for supporting some weight, but not the tubes themselves. In the rear, you really need to support the engine cradle and the walls as directly as possible while the bulkheads are being repaired. Sometimes it is better to just double up framework instead of cutting everything out. It sure is a lot easier to keep everything square and supported.

Work safe and use good judgement. What worked for me may not work in your situation.

Re: My rusty Star Destroyer

Posted: Tue Nov 11, 2014 9:04 pm
by tophatperformance
My thought was to use those points to get the bus level so I would have something to base measurements off of. Then support the roof front inside the bus with load bars from the floor to the roof. I can cross brace it to the floor inside. All the metal there is good. My primary worry is the bulkhead behind the front wheels. Look at the last pics and you can see it.
Thanks, Mike

https://secure.shoeboxapp.com/gallery/5 ... 8259a25b85