Materials compatibility
Hi Gang. Still struggling with my Philly. But I ran across a problem I thought some input from the experts might be advisable. The slide valve port face is made of common brass. I made the slide valve itself from an ingot of an unknown alloy of bronze, thinking the dissimilarity of materials would make a good combination. The face of the ports is galling . So the material combination is not satisfactory. Since the easier part to make are the valves,does anyone have a suggestion as to material ? I'm considering teflon, stainless steel (416), leadalloy, brass, phosphor bronze (of known composition). Thanks for your input. royce in SB
scale speed record [was: Survey is posted/scale speeds]
Hello All, On Great Trains Through the Garden, Volume 3, they show a segment of an Aster Grasshopper flying out of control, going amazingly fast, around a corner, and off the slightly elevated track. Luckily it was only elevated about 6 inches where it left the track. It was going so fast that the videographer had a difficult time keeping the camera on the little locomotive. Once it left the track the owner (presumably) rushed over to try to smother the flames with a towel. Finally the local fire department showed up (a hand holding a squirt bottle) and the fire was extinguished. It was sad, but I caught myself grinning at the amazing speed it reached. I have no way of knowing whose Grasshopper was shown, but the segment was titled Sonny's Garden Railway Steam Meet (or near that) and showed only live steam operation. The rest of the video (if I recall correctly) was sparkies. If any of you are contemplating trying to set a new scale land speed record, I strongly suggest you try to find this video to see your competition. Later, Trent P.S.- (with usual disclaimers) Great Trains Through the Garden, Volume 3 Produced by Close Up Videos P.O. Box 260704 Encino, CA 91426 It's a professionally done video, price unknown. Dave Cole wrote: Paul Quirk holds the current record at 155mph by the way. we gotta get tony dixon and paul quirk at the same steamup ... one of them will surely break the world landspeed record ... ;-) ...
Re: Materials compatibility
Hmm. If the materials are finished well, no sharp edges etc and you're using steam oil that is getting to the ports, I'm surprised that is happening. Phil P Hi Gang. Still struggling with my Philly. But I ran across a problem I thought some input from the experts might be advisable. The slide valve port face is made of common brass. I made the slide valve itself from an ingot of an unknown alloy of bronze, thinking the dissimilarity of materials would make a good combination. The face of the ports is galling . So the material combination is not satisfactory. Since the easier part to make are the valves,does anyone have a suggestion as to material ? I'm considering teflon, stainless steel (416), leadalloy, brass, phosphor bronze (of known composition). Thanks for your input. royce in SB
Re: Materials compatibility
Suggest cast iron (best material in the world ) bar non NO ECHO - Original Message - From: Royce Woodbury [EMAIL PROTECTED] To: Multiple recipients of sslivesteam [EMAIL PROTECTED] Sent: Wednesday, March 26, 2003 11:27 AM Subject: Materials compatibility Hi Gang. Still struggling with my Philly. But I ran across a problem I thought some input from the experts might be advisable. The slide valve port face is made of common brass. I made the slide valve itself from an ingot of an unknown alloy of bronze, thinking the dissimilarity of materials would make a good combination. The face of the ports is galling . So the material combination is not satisfactory. Since the easier part to make are the valves,does anyone have a suggestion as to material ? I'm considering teflon, stainless steel (416), leadalloy, brass, phosphor bronze (of known composition). Thanks for your input. royce in SB
Re: Materials compatibility
At 08:27 AM 3/26/03 -0800, you wrote: Hi Gang. Still struggling with my Philly. But I ran across a problem I thought some input from the experts might be advisable. Royce, I agree with Phil that this is perplexing (and I agree with Graham that C.I. is the best material in the world), but not necessarily in this case. Short of complete lack of lubrication there aren't enough forces or heat acting on the bits in question to result in galling, so I am preplexed. When thinking of dissimilar metals with respect to machine or steam bearing applications the two metals are ferrous (iron or steel) and non-ferrous (brass, bronze, copper, babbit) so brass and bronze aren't actually dissimilar in the sense we have here. Nevertheless they shouldn't be galling. Brass and brass ought to be holding up just fine even with little lubrication. Regards, Harry
OT: Tag Gorton, where are you?
All, sorry to use the list for what would otherwise be a personal aside. Tag, I tried to send mail to you just now, and the madasafish address I have was rejected. Where have you moved to? regards, -vance- Vance Bass Albuquerque, New Mexico, USA Small-scale live steam resources: http://www.nmia.com/~vrbass
Re: Materials compatibility
Royce, Although not on the list of recomemded bearing compatibily, I have been using hard Aluminum slide valves on Brass 360 for many years with out problems. 6061-T6 and 2024-T4 both work well. I lap both parts on a flat surface with 600 grit sandpaper and oil. Then clean very well and then clean again. Small scratches do eventually show up, but nothing that affects running. I have done several thousand cylinders that way for 35 psi saturated steam with no problems in that area. Other things wearing out yes, but no valve problems. These are 1/2inch bore cylinders. I have made a few engines with a cast iron port face about .03 inch thick and inserted between the chest and brass cylinder like a gasket with some Loctite gasket eliminator between the new and old port faces . Then run a cast iron valve against that. That almost insures success. If that moves the valve spindle too much you might be able to mill off enough of the existing port face to bring it back to where is was. This false port face used to be used on models quite a bit, but I have not seen it used for some time. Gail in NM
