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Hey guys, I pulled the cab off my 55 2nd series 6100 and when I put it back on I noticed something wasn't right. I used a 1/2 ton mounting kit not knowing that the rear mounts are different. I checked my assembly manual and now know what I need. I just don't know where to get the correct cushions. The old ones are in bad shape and only one of them is correct. Any ideas or do I have to make them? Thanks! SEE YA! Mark

Mark,

I had to make them for my 10500 series fire truck. They are 1-1/2" thick, so I went to my local industrial rubber supplier and got a piece of scrap that they use for snow plow cutting edges. I used a hole saw in my drill press to make them round. The edges aren't smooth like original, but they work! My truck required 4 pieces, one on top and one under the bracket on each side.

Mike B

Good tip Mike I may need to do that my self.
If a guy has to have them smooth or shape them you could dip them in liquid nitrogen to freeze them and use a belt sander. We even shaped rubber parts by freezing them and turning them on a lathe.

Thanks Mike, I kind of figured I'd have to make them. I'm going to try cutting them on the CNC. If I can find the rubber. See ya! Mark

Unless it's really hard or frozen rubber doesn't machine....
I've made nice holes and rounds in rubber with a sharpened thin wall tube spinning in the lathe and press the rubber onto it using dish soap as a lubricant. Sort of like combining the best of a hole saw and a hole punch all in one.

I bet you could have them water jet cut with good results.

Grigg

Hey Grigg, we've cut rubber on the CNC many times ,if you have the right tooling & right programing it works well. No freezing required. I just have to find the rubber . See ya! Mark

Grigg, Mark, Mike,etc., I too need to make new mounts for my 860 and of course went to my McMaster Carr catolog. I get confused with all the durometer ratings. I have bought rubber for other porjects and using their scale as a guide have still come up buying something a little too hard or soft.
I guess that is my fear, buying something that is one way or the other for a cab mount. Grigg, do you have any words of wisdom for making my selection.
Hope I am not stealling this thread. My add would be, as always, MC is a great resource for finding bits and pieces for a resto or build.

Billy,
It's difficult to pick the right one without dealing with rubber every day (I don't either) I've found the little comparison scale McMaster has in the catalog very helpfull before. The one where they show erasers, shoe soles, bowling balls and such as comparable to what durometer numbers.
http://www.mcmaster.com/#about-firmness-ratings-for-rubber/=g8tfpm

I'd guess for cab mounts you want something in the "Med. Hard" range.

Mark, curious to know more about how you machine rubber, what sort of tools? I've tried it on occasion with my manual machines and can usually come up with what I need in the end but it never works out how I expect, it's tricky... the soft stuff never works for me unless frozen or simply cut/sheared/punched and not machined.


Grigg

Hey Grigg, we use a single flute straight cutter designed for rubber. If I find the rubber I'll do a video of cutting it. See ya! Mark

Hey guys , Here's an update on what I decided to use for my cab mounts. I was looking online for rubber and had no luck. I read Bill's post on McMaster - Carr and gave that a look. Thanks Bill! The flat stock seemed too expensive. Sorry Grigg no CNC video! I saw they had rubber tubes so I explored that route and bought a 6" piece- part # 8637K311photo, it is 2 1/2' OD[that's 1/4" larger than original] with 3/4" ID and a 75A durometer rating[ that is considered a hard rating].It is neoprene & is oil, impact & weather resistant. I had one original cushion & compared it to the new rubber & the hardness seems very close. It cost $17 with shipping. The cushions need to be 1 1/2" thick so 6" was just enough. I cut the rubber into 4 - 1 1/2' pieces on my bandsaw photo. I also bought 2 - 7/16"-14 X 6" grade 5 carriage bolts,the manual shows hex head bolts photo - exploded view,but my cab had carriage bolts and that looks correct. Lastly I needed the spacers & washers which I was lucky enough to find some scrap tubing & flat stock at work.The spacers are 3/4" OD X 1/2" ID X 2 7/16" long photo. For the washers I used 3/16" flat steel [3/16" is a little too thick but that's all I had] and cut them out with a 2 5/8" hole saw, that gave me a 2 1/2" OD. I then drilled the center out to 1/2" photo. I hope to install everything soon. I guess only time and driving the truck will tell if it all works properly. SEE YA! Mark

og55,

Thanks for the update!

Mike B