16 replies to this topic

[CROW]

Hey 'Haven. I'm building a breech with 17/32" and 9/16" brass. Each piece has a gap, and when the two slide far enough along each other, the gaps line up and theres a hole to put the dart in. What my problem is, is that the brass slides horribly. It takes enough force to slide the two that I doubt it will be worth having the breech on the gun. Any clues on how to solve this?

(I've made sure there are no points of contact between the two pieces. Is it possible that I just just a slightly oversized piece?)

[atomatron]

Did they slide well before you cut them?

*EDIT*
Did you also clean up the inside of the cut on the 9/16th piece?

Edited by atomatron, 12 June 2009 - 08:57 PM.

[Zorns Lemma]

Clean up your cuts and maybe clean the brass. I've found 17/32 to be tighter in 9/16 relative to the fit of 9/16 in 19/32, so any flares or glue on the brass is going to make life very difficult.

[CROW]

To be honest, they didnt slide that well beforehand either. I'm starting to think that the pieces I got were just a little too small or a little too big. I'll probably end up redoing the breech with better pieces unfortunately...

[The Kart Racing Nerf Man]

I had this same problem... I used very fine sandpaper and sanded the cuts that I made and most of the entire brass piece. Try it, it worked for me perfectly.

Edited by The Kart Racing Nerf Man, 12 June 2009 - 11:07 PM.

[pjotrkuh]

Maybe (I could be mistaking) there is a weld line along the lenght of the tube on the inside, or the tubes are slightly bended when transported or cut.

Edited by pjotrkuh, 13 June 2009 - 12:26 AM.

[jackster57]

I am not sure about you, but all of my brass comes with little stickers telling the size of the pipe. After I take off those stickers I have to be sure to completely sand off all of the residue or the brass has trouble sliding. Try that.

[Lt Stefan]

I am not sure about you, but all of my brass comes with little stickers telling the size of the pipe. After I take off those stickers I have to be sure to completely sand off all of the residue or the brass has trouble sliding. Try that.

Yes I would agree with that. Also, if the brass is old, tarnishing could be a problem. Or they might be slightly dented.

[Possemhunter]

If you use pipe cutters, there is a large flange left behind. File that off with a round file.. I prefer to use a dremmel to cut brass because it leaves less of a flange behind and is a zillion times quicker. You still have to file a bit though.

[atomatron]

I am not sure about you, but all of my brass comes with little stickers telling the size of the pipe. After I take off those stickers I have to be sure to completely sand off all of the residue or the brass has trouble sliding. Try that.

Wouldn't Goo-Gone also work?

[Lt Stefan]

I am not sure about you, but all of my brass comes with little stickers telling the size of the pipe. After I take off those stickers I have to be sure to completely sand off all of the residue or the brass has trouble sliding. Try that.

Wouldn't Goo-Gone also work?

Lots of methods would work.

[CROW]

I'll give a little sum up of what I've done: I've sanded both pieces with fine sandpaper until they were perfectly smooth, added silicon lubricant, filed the insides of ALL the edges of the larger, outer pipe, sanded all the outside edges of the smaller, internal pipe, and bent any cuts back into place. The damn breech still doesnt slide. I've done just about everything possible I think, so I'm heading back to the hobby store for more pipe and a rebuild.

Edited by CROW, 13 June 2009 - 01:04 PM.

[Wes7143]

Valve oil. For use with brass trombones, preferably.

[Merzlin]

I would have never thought of Valve Oil, and I play the trumpet! I have a couple bottles for all my brass instruments, I'll have to try that out.

[SorrowX]

Your brass and quite possibly your cuts aren't clean. You are going to need steel wool(Brillo Pad), paper towel, and a product called Brasso. First, use your steel wool and scrub your brass down, and put a bit of focus on your cuts. Now get a piece of paper towel and roll it up, then put a small amount of Brasso and run it through the inside of each one of your tubes. Then get another piece of paper towel and rub down the outside of each tube with a bit of Brasso. Then scrub down with the steel wool and rinse your tubes with water; they should slide very smoothly once they dry. I do this all the time with my brass, and I assure you, it has never failed me before. Hope this helped!

Edited by SorrowX, 14 June 2009 - 01:27 PM.

[nerfnrg]

If you want to try the Valve Oil thing, try using a Q-tip to do the inside of the 9/16 brass. For the 17/32, just squeeze a few drops and if that doesn't work, get a few bottles of valve oil and dunk them all in a cup. Then dunk the 17/32 into the cup. Well, I don't know if valve oil works but 2 other people suggested it so I'm just suggesting how to do it.

~nrg

[bobbybilly60]

Valve oil contains vasiline. It may ruin rubber that is in contact with it and all the stuff vasiline ruins.