View previous topic :: View next topic |
Author |
Message |
tom pennell Regular Member
Joined: 28 Mar 2016 Posts: 67 Location: Melbourne Australia
|
Posted: Sun May 02, 2021 10:04 pm Post subject: Conn 38B valve caps |
|
|
I have a 38B Conni, serial number 624xxx, dating it to 1956/57. My question relates to the valve caps. My caps have the recessed "channel" intended to take felts. Photos on Connloyalist show the early models as having a different cap with no provision for felts,as introduced on later models. The early model caps appear to have a collar, mine does not, just the recess into which the felt rests. The buttons on mine are of the earlier model, quite different to the later model. My question is, does the inclusion of the felts on what appear to be the later model caps compromise the valve stroke? I have removed the felts so the button now sits flush with the top of the cap, albeit with some noise! I suspect the valve caps have been changed at some point. Should I be concerned? Regards Tom |
|
Back to top |
|
|
deleted_user_687c31b New Member
Joined: 03 Apr 1996 Posts: 0
|
Posted: Sun May 02, 2021 10:17 pm Post subject: Re: Conn 38B valve caps |
|
|
tom pennell wrote: | My question is, does the inclusion of the felts on what appear to be the later model caps compromise the valve stroke? |
Not sure about the stroke, but it can mess with the valve alignment. If there are no felts, the valve can go slightly deeper than with felts. This may cause it to misalign with the tubing, which at best will only add resistance, but can also compromise tone and even intonation. All of this applies to a lesser degree to metal caps vs. caps with a felt insert of the same thickness, as felt compresses and metal does not, and from what I've read millimeters matter for valves.
I'm no expert on valves, but there are dozens of stories on TH about 'precision valve alignments' so I imagine it could potentially have a significant impact on your playing. Last year, I had an old peashooter stencil trumpet that used corks rather than felts, but when I took the valves apart to clean them, the corks disintegrated and the valves went both further up and farther in. That made for some serious intonation problems that only went away when I added some felts as replacement.
Then again, for you it may have no impact at all. |
|
Back to top |
|
|
delano Heavyweight Member
Joined: 18 Jan 2009 Posts: 3118 Location: The Netherlands
|
Posted: Sun May 02, 2021 11:47 pm Post subject: |
|
|
Your horn seems to have the wrong valve caps. That can be a problem because in fact there are two different systems. On the old ones the collar of the valve cap stops the (old style) valve button on a soft ring inside the valve button. In the more modern system the valve botton is stopped by the outside of the valve button on the felt ring in the valve cap. You seem to have mixed systems. If that's creating a problem with the alignment of the valves is not sure. I don't think it's a good idea to remove the felts from the valve caps. In the old system, the button is stopped inside, the outside will not touch the valve cap. So there is some space left which can be enough to make up for the difference in thickness between the old and new buttons (in fact the old Conn buttons differ the most in thickness on the top of the button, not on the downside). I only own old school Conn horns so I am not sure how much the thickness of the different valve caps differ. Still I suppose that if you put the felts back on the alignment of the valves will not be that far off. You can control that by taking out the second valve slide, depress the valve and then you can judge the alignment. If necessary you can correct the alignment with thicker or thinner felts in the caps. But the real deal is to get the original caps with the collar.
Last edited by delano on Mon May 03, 2021 4:54 am; edited 4 times in total |
|
Back to top |
|
|
stumac Heavyweight Member
Joined: 19 Nov 2008 Posts: 697 Location: Flinders, Australia
|
Posted: Sun May 02, 2021 11:58 pm Post subject: |
|
|
Hi Tom,
put it back how it was, it needs the felts in the caps to get correct alignment, I checked it when I fitted new valve springs.
Regards, Stuart. |
|
Back to top |
|
|
Dale Proctor Heavyweight Member
Joined: 26 May 2005 Posts: 9367 Location: Heart of Dixie
|
Posted: Mon May 03, 2021 5:03 am Post subject: |
|
|
It’s pretty easy to check the valve port alignment on the downward stroke. Just remove the valve slide and look down the tubing toward the valve. Depress the valve and see how well the ports line up, and adjust the felt thickness accordingly.
If you have a mixture of caps and buttons from different eras, the only solution could be finding the correct ones, but it’s worth a try to check the downward valve alignment first. _________________ "Brass bands are all very well in their place - outdoors and several miles away ." - Sir Thomas Beecham |
|
Back to top |
|
|
tom pennell Regular Member
Joined: 28 Mar 2016 Posts: 67 Location: Melbourne Australia
|
Posted: Mon May 03, 2021 2:55 pm Post subject: |
|
|
Many thanks for the considered responses. Yes Dale, I did check the port alignment both before and after removing the felts, all seemed O.K. I have taken stumac's sage advice and returned the caps to the condition they were in, again checking the port alignment. In any event, the later style caps and felts make the horn a better looking instrument!
I guess I was just over intellectualising a perceived problem. Regards Tom |
|
Back to top |
|
|
Andy Cooper Heavyweight Member
Joined: 15 Nov 2001 Posts: 1833 Location: Terre Haute, IN USA
|
Posted: Tue May 04, 2021 6:23 pm Post subject: Re: Conn 38B valve caps |
|
|
tom pennell wrote: | I have a 38B Conni, serial number 624xxx, dating it to 1956/57. My question relates to the valve caps. My caps have the recessed "channel" intended to take felts. Photos on Connloyalist show the early models as having a different cap with no provision for felts,as introduced on later models. The early model caps appear to have a collar, mine does not, just the recess into which the felt rests. The buttons on mine are of the earlier model, quite different to the later model. My question is, does the inclusion of the felts on what appear to be the later model caps compromise the valve stroke? I have removed the felts so the button now sits flush with the top of the cap, albeit with some noise! I suspect the valve caps have been changed at some point. Should I be concerned? Regards Tom |
1.The alignment with your present set up is probably OK. I checked it with my 6B using old caps and a top with no felt. But you can't really play the horn that way with its own built in rhythm section.
2. Easiest solution is put the felts back and replace the finger buttons with the smaller newer ones from the late 50's or 60's. I believe Allied Supply still stocks them (available from your music store) or it might be cheaper to purchase a junk Conn director cornet or trumpet with the newer (60's) correct valve buttons. These buttons use no corks or felts - just the felt in the top cap. (Be sure you get one made in USA not Japan)
2. Keep your early finger buttons and replace the top caps. Again, look for an older junker Conn Director with the correct valve caps on shopgoodwill.com. You can often get a "parts" only cornet for under $40 including shipping.
3. King 600 finger buttons will also work with the newer Conn tops - though it might take thicker top cap felts or set screws in the valve stems. They are close.
3. Custom buttons or top caps from Harrelson.
Odds and ends:
You can use the 60's finger buttons with the early top caps if you add cork and felt to the finger buttons.
The newer top caps are much heavier that the old ones. If you have extras they work just fine as heavy bottom valve caps. |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|