Prevost Parts

[luvrbus]

I thought I would do a follow up post on my adventure of getting a simple replacement alternator tensioning arm for my supplemental 12V alternator that charges the original house battery system.

Bus is 24V with a separate alternator and hey I needed to replace both alternators!!!

Anyway the alternator tensioning arm is special order from Prevost and was only on the motorhome version of the bus.

I found a local firm that would 3D scan it and water jet cut a new one for $200.00 with a 10 day lead time which is just going to under the wire, before I take off for the BCI rally.

After I dropped it off I asked Prevost if there was an engineering diagram which they sent me.



As I mentioned earlier I entered this as a drawing sketch in FreeCad, translating to metric as I did it.



I then exported it as a SVG file and took it to the local maker space and laser cut it out in cardboard for comparison against the original. Which due to the holidays I haven't been able to do yet.



Then a wild hair occurred to me today what if I sent it out be 3D printed in metal?

So I converted the drawing sketch to a 3D object and submitted it to a couple of services for a quick price quote.



1. Shapeways came back with a price of $370.00 for steel unspecified.
2. Craftcloud3d gave me a hole bunch of options, some of them are:
    a. 316L Stainless Steel $310.00
    b. TPU (Rubber) $54.00
    c. Titanium $1837.00
    d. Bronze $3145.00
    e. Maraging Steel (tooling) $764.00

They had an option for gold but didn't quote it LOL!!!

If my design replication effort works I am hoping they will produce the part for less than the original $200.00 quote.

You can get a 200 amp alternator from a military surplus that has both 12 and 24 volt charging I installed on Mike and Kays MCI 9 changing out the old gear driven 50D alternator to a belt drive and doing the same on LVMCI model C .Like John said all those brackets were made with a torch,drill press and a welding machine lol I am old school I still use the old stick rod.you could find one close at a truck wrecking yard for probably less than 20 bucks 

[Jim Blackwood]

Last one of those I made, I welded it up out of pieces and was pleased with the results. It's much easier to match the curve bending smaller bits to form the slot on both sides than it is to either bend the strap and then cut a curved slot, or cut the slot and than bend the curve. But, you do have to get full penetration on your welds for it to stay together. Another option is to cut the slot in from the end using a drill and a saw and making it longer than needed, then bend it, then weld in the end piece.

Jim

[luvrbus]

Best to take a wider piece of metal and cut the curve for me

[Tedsoldbus]

Fred,
I showed this to the young guy I told you about (Austin). He said the curve is no problem. Does it have any bends in it like mine did to line up with the frame or is it flat? My cracked one had 2 bends in it he matched exactly. He made it wider, thicker, better bla bla bla and powder coated it for $20 dollars (like the price the really smart guy above mentioned). Austin uses tough stuff. He smiled after we put the new one on and said "You won't break that". If the one you are pondering making is flat send me an exact cardboard or even paper copy and Austin will fix you up. Exactly.
I know it is a Prevost buddy but we are your friends and trying to save you from making it out of metal from the Space Shuttle or whatever these guys are promising. Save your money for when a tree breaks one of those curved windows. (I know that is one of my biggest fears.)
Print exactly what you want and mail it to me. I'll fix you up.
Ted

[freds]

Hi Everyone

After volunteering to act a gopher for any needed parts my local makerspace brought their CNC Plasma cutter online!!!

After burning a few hours of time watching YouTube videos and then a fair amount of thinner metal as I came up to speed on instructing the software what I really wanted done.

I was able to transition to cutting 1/4 steel to make the replacement 12V alternator tensioning bracket.

Who says an old dog can't learn new tricks LOL!!!

Anyway here it is:



The hardest part was attempting to add the clearance bends with a vice and hammer. There is an engine reference face and the engine mount which requires the offsetting bends for clearance.

Hey if nothing else I will get a longer bolt and some washers to make up the difference if I didn't get it right.

[freds]

Finally got around to taking a picture of the new plasma cut bracket installed.

[Ed Hackenbruch]

I went to a truck wrecking yard, found two that i thought might work, $15 for both. One worked, the other didn't.