How to modify Fitting

I just joined this forum and I don't have a whole lot of machining experience so I'm looking for some good'ol practical advice.

I am modifying the fuel cross-over line from my VW van because the nylon fittings are breaking every few years. These little pieces of plastic end up costing $64+ for a replacement and I'm done shelling out that kind of cash for plastic that doesn't last. So I am going to a brass fitting but I need to modify it slightly.

The plastic fitting has a 0.4" long shoulder which is 0.5" in diameter and I need to recreate that on the barbed brass fitting. See pic.

What would be the easiest and most cost effective way to achieve this? Would I use a lathe or a mill?

My concern if I use a lathe is how to fixture the part because it wouldn't be balanced.

Thanks for your help.

I'm not sure what machines you have available. If you have a cnc mill you could just use a t-slot cutter. I personally don't see a problem with a lathe as long as you keep the rpm's down.

Mike

Put it in a vise and use a hack saw or cut-off wheel. Then debur any sharp edges.

One thing you want to check is the I.D. because if it is too small or too large you won't get the proper flow.

I'd just use a file.

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Originally Posted by five12dude

I just joined this forum and I don't have a whole lot of machining experience so I'm looking for some good'ol practical advice.

I am modifying the fuel cross-over line from my VW van because the nylon fittings are breaking every few years. These little pieces of plastic end up costing $64+ for a replacement and I'm done shelling out that kind of cash for plastic that doesn't last. So I am going to a brass fitting but I need to modify it slightly.

The plastic fitting has a 0.4" long shoulder which is 0.5" in diameter and I need to recreate that on the barbed brass fitting. See pic.

What would be the easiest and most cost effective way to achieve this? Would I use a lathe or a mill?

My concern if I use a lathe is how to fixture the part because it wouldn't be balanced.

Thanks for your help.

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As suggested, keep the speed down at the lower end of the range. The fitting is light enough that it wouldn't bother even a 7x12 mini-lathe. If it is mounted into something considerably heavier and then mounted into the mini-lathe chuck the total mass may have some effect if it is not centered.

That's not going to be easy - but try to devise a way to clamp it in a four jaw independent chuck so that you can dial indicate it into being centered on the spindle bore before turning it to size. One leg may be able to protrude sideways out between the jaws. If the barb grooves are smaller than .5" you can silver solder the grooves to build it up and then turn it to .5" diameter.

CarveOne