I've made some custom urethane bushings for our V8 beetle project. I'm using trailer leaf springs and modifying the stock s10 mounts and shackles. Obviously I can't just go out and buy bushings to make this work, so I made them Plus I just like making my own "stuff" whenever I can

I ordered some casting urethane rubber form McMaster Carr. I'm an industrial mechanic in an aluminum foundry and I've used this stuff before to repair seals, make molds to cast ceramic ladles, etc........ Its neat stuff and it comes in 2 parts. You mix the two together and pour them into your mold. I think they just take 48 hours to dry, no baking required.

I ordered part #8644K11 from www.mcmaster.com that was 25 cubic inch flexible casting urethane kit that had a 80 shore A hardness flexible casting urethane and it cost around $30.

I'm no expert on this so this might not be the "right" way to do this, but its how I did it. Here are some pics, you can see some more on my website at http://www.zbcreations.com/chassis6.html. I haven't finished them yet though because I want to clean up and paint the chassis before I stick in the bushings, that and I also just have some of the stuff tac welded right now and I don't want to put in the bushings and melt them when welding later on............ LOL

I made the molds out of some steel tubing that I'm going to use to house the bushings. That way the bushings are the correct diameters. I turned some bases out of some HDPE plastic so the tubing pressed into that and I had a hole drilled in the base for some 3/4" nylon rod that I had for a center core to leave a hole for the bushing spacers. The yellow mold is what I poured all the extra into to make some body mounts. Oh yeah I used some petroleum jelly for mold release.

Here I have the bushings poured

Here they are popped out of the mold. The two longer ones will get cut in half and be inserted into both sides of my rear shackle mounts on the frame. The smaller ones will get bushing spacers in each one that will got into the eyelets of the springs, and the rubber bushings will be housed in the steel tubing welded inside the shackles. Kinda hard to explain, sometime I need to make a drawing of it, or roughly assembly it or something.

For the bushing spacers I found some tubing with a 9/16" id and 3/4" od. That way my 9/16" bolts would be a nice fit inside of them, and it fit the 3/4" ID of the bushings. I turned down one end of each spacer so that they will press into the eyelets of the springs.

The bushings will then slide onto the other end of the spacers, and will be housed in the tubing I used for the molds, which will be welded to the insides of the shackles. The bushings will be able to rotate inside the tubing and the spacers will also be able to rotate inside the bushings when the suspension moves.

Like I said it might be a bit hard to follow what I'm doing........... But I have it all figured out in my head......... LOL

I hope this helps, let me know if you have any questions.

 

I've made some custom urethane bushings for our V8 beetle project.

Pretty slick!

Tell me, does the material come in different durometer ratings? Or is there any way that you're aware of that would allow for stiffer or softer "rates"?

I'd like to do some body mounts that need to be stiff, up near 100 wouldn't be too hard, IMO.

 

X2 what cobalt said, good stuff there zbhover :thumbup: This would be a great wiki article.

Did you need to dimension your molds at all to allow for any shrinkage when the urethane cures? Or are you sizing the inner bushings to allow some crush on the urethane?
Just curious.

Later, mikey

 

that is exactly what I want to make, seems like you and I share this love for making our own stuff.

but I doubt I would find the urethane in this neck of the woods, this is why I wanted to use rubber instead, this country is a big rubber producer and buying latex is easy and cheap, have you ever made rubber stuff?

buying the urethane from the USA would be very prohibitive, do you know of an industrial trade name for it, say like to buy some nylon plastic for bushings or gears, here I ask for duralon.

I've seen even engine mounts repaired by re-vulcanizing rubber on them, but can't find the guy who does them, besides I would love making my own castings, just the way you did yours.

thanks

Augusto.

 

Cobalt:

Yes it comes in a wide range of durometers.

go to www.mcmaster.com and search for casting compounds. It looks like they have the flexable from 20a up to 94a. They also have castable solid urethane from 85D-90D, along with putty and some other stuff.

Powerrodmike:

I'll have to make up a wiki article about it when I get some more pics.... and more time....... LOL

The stuff only shinks .0005" per inch of thickness so there is no need to worry about making your molds over sized.


Augusto:
I try to make/do everything I can myself. I also design and build hovercrafts and I pretty much designed and built everything except for basically the engines:

I've also used 2 part pourable rubber from a local industrial supply place at work to line suction lines for large vacuumes we use to suck up sand at work. I don't know if latex would be strong enough though. I didn't realize you wern't in the US, but if you have some kind of an industrial supplier over there I'm sure you could find something simular to this stuff.

There is a trade name for this stuff its Devcon Flexane if that helps. McMaster Carr just sells a "generic" version of it I guess, the flexane is a bit more expensive, but it might help in your search for some locally.



Let me know if you guys have any more questions............

 

HOVERCRAFTS!!! yes I love them, I tougth of making one long ago, I planned using a yamaha go-kart 2 stroke engine tilted vertically to power a fan to inflate it and a Toyota 1.3 litre 4 cylinder to power the rear fan but the project never was more than an autocad file.

I would love seeing more of your toys, do you have pictures posted somewhere?

I'm gonna do a search for Devcon Flexane, it migth be available here, hope so, thanks a lot.

Augusto.

 

For more pics of lots of my projects just go to my profile and my website is listed there, I have thousands and pics on my site.

 

zbhover -- may I have your permission to copy-paste your post and pics into the wiki? I'll do all the initial uploading and editing, and once it's in there, you (or anyone else) can fine-tune and adjust the article.

 

zbhover -- may I have your permission to copy-paste your post and pics into the wiki? I'll do all the initial uploading and editing, and once it's in there, you (or anyone else) can fine-tune and adjust the article.

Sure go ahead, sounds fine to me. Next time I have the beetle pulled out of the garage I'll see if I can't get some more pictures to add to the article.

Thanks

 

Thanks zbhover -- the article is here: Making rubber bushings. Please review for accuracy, and edit as desired. It's mostly verbatim, but, per wiki conventions, I've changed it from first-person, so that others will feel comfortable adding to the article.

 

Hey, my question propeled you into wiki-famous... he he, I should get a prize :thumbup:

nice articles you have there, the V8 VW is very nice, I once widenend the fenders of a VW to stuff very wide tires, it's not big deal, cut them in half through the middle and insert a piece of sheet metal, I added 2 1/2 inches and the result was very nice, I wish I had pictures to show.

btw the car looked awsome with the ultra wide tires but handled terrible, it was like driving on ice, a litle dirt or water on the asphalt amde things miserable.

I think I'll make a hovercraft like yours some day, I'm gonna study all you pics.

saludos from the middle of the planet.

Augusto.

 

Thanks John, looks pretty good to me, like I said I'll try to get some more pics and info soon and add to it. I'll also see if we have any pictures at work of some of the other things we've used the stuff for.

Augusto:

Thanks, I thought about widening the fenders on the VW, but figured that since, I'm doing all the work, why not chop the car in half down the center and widen the whole car to give us some more room :thumbup:

If you ever decide to get into hovers shoot me an email, and I'll help out where I can.

 

I tougth of doing that to a Zastava 750 ( you probably have never seen one of those in the USA, looks like a shrinked VW) but chickened out because the trouble of making a new windshield and rear window, tell me how are you going to deal with it, well the bug has a flat windshield, piece of cake make one bigger but the curved rear window???

I'm interested on it because this friend has one that I was convincing him of intalling a geo metro engine and transaxle in place of the rear seat, widening the whole car woul make it even nicer, sure it would end up like a nice pocket rocket.

I installed a Subaru 1.600 engine on a VW once, it was awsome!!!

Augusto.