woodturner-fran said:
I put mine in the next room under the couch, which is about 6 ft of tubing. I turn it on as needed with one of those foot petals used to turn on the xmas tree
I do hear some noise when I don't close the door. I think I may stick it in a box with fiberglass insulation.
I'm part way through a terminator style arm, so I interested in your trials and tribulations. By the way, given your moniker, I wonder if you had thought of turning an arm? I have some thoughts on this; but not enough to put into words...
jkeny: thanks for the word of the day 'gobshite'. I like getting closer to my Irish roots in ways my parents wouldn't have taught me
Thanks staggerlee. Will investigate some foam I think...
Yes, I did think of a wooden armwand - but for now at least I've used some carbon fibre just cos its handy and what the termiantor maker uses! The pivot is made from lignum vitae though (and as yet unfinished).
I would say low cost project, but high man hours. Each part is cheap, but you need to be pretty pernickity about getting each part fitting just right. EG the carriage on mine works better when facing one way compared to the other!
Fran
Yes, I did think of a wooden armwand - but for now at least I've used some carbon fibre just cos its handy and what the termiantor maker uses! The pivot is made from lignum vitae though (and as yet unfinished).
I would say low cost project, but high man hours. Each part is cheap, but you need to be pretty pernickity about getting each part fitting just right. EG the carriage on mine works better when facing one way compared to the other!
Fran
Staggerlee
Ah, yes gobshite, literally translated into somebody who is talkingshite. The best thing about Irish terms of abuse is that they don't get picked up by the automated swear filter.
If I had found that little gutter-snipe that had fired the arrow I would have made sure that the shitehawk never did it again!
(There's another two terms to add to your vocabulary)!!
Ah, yes gobshite, literally translated into somebody who is talkingshite. The best thing about Irish terms of abuse is that they don't get picked up by the automated swear filter.
If I had found that little gutter-snipe that had fired the arrow I would have made sure that the shitehawk never did it again!
(There's another two terms to add to your vocabulary)!!
attention all non-gobshites
Things moved on again.... I'm just at the stage of mounting her up on the TT and getting a cart fitted. Arm lift now sorted, pivots cleaned up and best of all, I think I will get away with just using one pump which would make things a little quieter. Those things are damned noisy and no matter what kind of foam etc I surrounded them with, the hum was just as loud. It was like black magic... put it in a foam surround and it was just as loud. Anyways, hopefully with just one pump and putting it behind a sofa it will be low enough to be non-annoying.
the all important pics:
Hopefully it will all be ok. Now I'm worried I cut the CF arm a bit short, but hopefully it will be ok.
**************************
Now, the questions:
1. Counterweight: Am I better having a bigger weight right close to the pivot point or am I better having a lighter weight further back?
2. Pivot points: How should these be positioned? Should the pivots be level with the stylus or is a little up or down ok?
3. Arm wand lenght: Could someone give me a measurement from the end of their arm wand (ie spindle) to the manifold front edge?
Many thanks!
Fran
Things moved on again.... I'm just at the stage of mounting her up on the TT and getting a cart fitted. Arm lift now sorted, pivots cleaned up and best of all, I think I will get away with just using one pump which would make things a little quieter. Those things are damned noisy and no matter what kind of foam etc I surrounded them with, the hum was just as loud. It was like black magic... put it in a foam surround and it was just as loud. Anyways, hopefully with just one pump and putting it behind a sofa it will be low enough to be non-annoying.
the all important pics:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Hopefully it will all be ok. Now I'm worried I cut the CF arm a bit short, but hopefully it will be ok.
**************************
Now, the questions:
1. Counterweight: Am I better having a bigger weight right close to the pivot point or am I better having a lighter weight further back?
2. Pivot points: How should these be positioned? Should the pivots be level with the stylus or is a little up or down ok?
3. Arm wand lenght: Could someone give me a measurement from the end of their arm wand (ie spindle) to the manifold front edge?
Many thanks!
Fran
Got the arm mounted up last night. Took a lot of tweaking to get it sounding pretty ok, but I think there is more to get out of it yet. I need to go bakc and level everything now again and get it all set correctly.
Yes, it is very sensitive to set up. 2 pumps sound better than one. Parallel to platter and both level is vey important. Sonics are good.
Noise part solution: i put both pumps in a small flight case surrounded by foam down at the back of the sofa. I can still hear it, its still annoying, but is better than it was. The only solution to this is to put the pumps further away. I need to try Stews thing with the tube as well.
More later and hopefully pics!
Fran
Yes, it is very sensitive to set up. 2 pumps sound better than one. Parallel to platter and both level is vey important. Sonics are good.
Noise part solution: i put both pumps in a small flight case surrounded by foam down at the back of the sofa. I can still hear it, its still annoying, but is better than it was. The only solution to this is to put the pumps further away. I need to try Stews thing with the tube as well.
More later and hopefully pics!
Fran
Hi Fran nice project that your making.
I'm thinking to make an terminator style arm myself.
Bud i have been wondering did you or anyone else have done some experiments with different sizes of angle?
I see that you are using 25mm angle bud why not 30mm?
A bigger surface crates more lift and more stability.
As a result you need a lower pressure.
Is this thinking just to simple or is it getting to big?
Regards George
Please excuse me for my terrible English bud it is not my native language.
I'm thinking to make an terminator style arm myself.
Bud i have been wondering did you or anyone else have done some experiments with different sizes of angle?
I see that you are using 25mm angle bud why not 30mm?
A bigger surface crates more lift and more stability.
As a result you need a lower pressure.
Is this thinking just to simple or is it getting to big?
Regards George
Please excuse me for my terrible English bud it is not my native language.
Hi Geosto,
I don't know the answer but I suspect its a number of things. The 25mm works and its widely available pretty cheap. The bigger you go, yes, the bigger the whole thing gets and the heavier the carriage gets too. From reading the terminator site, much seems to be made of the fact that the arm has a low mass. I made my carrier from wood rather than alu just to keep the mass down.
As regards pressure, the aquarium pumps I use are just 1.75psi - and you can bet that its probably even less than that (I'm just going by what it says on the outside of the box). But the tradeoff for using low pressure is that you need more airflow I think. Higher pressure means more hiss at the arm itself (I have none)and likely more compressor noise.
The biggest drawback of this arm is the noise of the pumps. I think that the first thing you should do if you are thinking of making one of these arms is to figure out a way to mount the pumps in another room far enough away so that you won;t hear them. I listen mainly late at night after everyone else is in bed, the house is quiet and they are quite audible.
My 2c!
Fran
I don't know the answer but I suspect its a number of things. The 25mm works and its widely available pretty cheap. The bigger you go, yes, the bigger the whole thing gets and the heavier the carriage gets too. From reading the terminator site, much seems to be made of the fact that the arm has a low mass. I made my carrier from wood rather than alu just to keep the mass down.
As regards pressure, the aquarium pumps I use are just 1.75psi - and you can bet that its probably even less than that (I'm just going by what it says on the outside of the box). But the tradeoff for using low pressure is that you need more airflow I think. Higher pressure means more hiss at the arm itself (I have none)and likely more compressor noise.
The biggest drawback of this arm is the noise of the pumps. I think that the first thing you should do if you are thinking of making one of these arms is to figure out a way to mount the pumps in another room far enough away so that you won;t hear them. I listen mainly late at night after everyone else is in bed, the house is quiet and they are quite audible.
My 2c!
Fran
Noise redux...an idea...
woodturner-fran, if all else fails:
while reading the last couple of responses in this thread an idea "struck" me...what about active noise reduction? Small T amps are available quite cheaply (or even an old unused amp of any sort), a microphone and a small speaker. Mount the speaker in the same box as the pump(s) and wire it out of phase...or make a recording of it and play it through an mp3 player to an amp , and wire it out of phase.
As the sounds these pumps make are very periodic in nature, this should prove effective, without straining almost any amp or speaker.
Dumb simple, but should be effective.
stew
woodturner-fran, if all else fails:
while reading the last couple of responses in this thread an idea "struck" me...what about active noise reduction? Small T amps are available quite cheaply (or even an old unused amp of any sort), a microphone and a small speaker. Mount the speaker in the same box as the pump(s) and wire it out of phase...or make a recording of it and play it through an mp3 player to an amp , and wire it out of phase.
As the sounds these pumps make are very periodic in nature, this should prove effective, without straining almost any amp or speaker.
Dumb simple, but should be effective.
stew
Thats not a bad idea Stew. It requires a bit of work. Now what I need to do is trade off drilling a hole through concrete to the next room or making the active noise cancellation.
What I'm going to do first though is live with it for a little while and make sure the arm is worth it. Initial listening shows much promise. I think if I went back around all the setttings yet again and touched them all up that it would give yet another improvement, albeit smaller.
However the thing is though that already there are some records that were almost unlistenable on the old arm due to some distortion (some cut a bit hotter on the inside grooves?) and they sound A1 now. It also passes track 3 of the HFNRR test record cleanly but not the 4th. I got near this before but never quite made it past track 3. Yeah, there is a cleanness and expecially treble is a fair bit sweeter now.
The customary pic:
And a link to a short vid on youtube:
http://www.youtube.com/watch?v=hoEBEGS1cEk
Fran
What I'm going to do first though is live with it for a little while and make sure the arm is worth it. Initial listening shows much promise. I think if I went back around all the setttings yet again and touched them all up that it would give yet another improvement, albeit smaller.
However the thing is though that already there are some records that were almost unlistenable on the old arm due to some distortion (some cut a bit hotter on the inside grooves?) and they sound A1 now. It also passes track 3 of the HFNRR test record cleanly but not the 4th. I got near this before but never quite made it past track 3. Yeah, there is a cleanness and expecially treble is a fair bit sweeter now.
The customary pic:
An externally hosted image should be here but it was not working when we last tested it.
And a link to a short vid on youtube:
http://www.youtube.com/watch?v=hoEBEGS1cEk
Fran
jkeny:
Thanks for that quote, it saves a lot of searching. I notice that vic (ie Mr. Terminator) uses an alu block to hold the arm wand and knives. I used some dense wood to save a bit on weight. Maybe the little extra weight might help there though. .... to be explored.
Stew:
Thanks - theres not much machining involved other than cutting the alu angle to length and drilling the small holes. So cutting and drilling really.
Lathe work and milling would help it look a lot better though, but for an initial work up, you don't need it.
Fran
Thanks for that quote, it saves a lot of searching. I notice that vic (ie Mr. Terminator) uses an alu block to hold the arm wand and knives. I used some dense wood to save a bit on weight. Maybe the little extra weight might help there though. .... to be explored.
Stew:
Thanks - theres not much machining involved other than cutting the alu angle to length and drilling the small holes. So cutting and drilling really.
Lathe work and milling would help it look a lot better though, but for an initial work up, you don't need it.
Fran
Ideally yes, if you use say 25mm angle for the carriage, then use 50mm box for the hangers - its a nice idea to partially cut away some of the box then makes life easier swapping in and out the armwand as well as reducing weight.
I just bent some flat alu bar I had though around a former and then ground the bottom to a sharp angle.
Fran
I just bent some flat alu bar I had though around a former and then ground the bottom to a sharp angle.
Fran
ha, very impressive stew - only that looks better than my implementation!
Mine is more or less the same except that I put the pivot points further away from each other (ie the cross piece is longer). I used ordinary kitchen knife because I thought the stanley knife blades were very brittle and thin and could chatter. Although it looks like thats what Mr. Terminator uses.
I wonder what a little silicone grease on the pivots would do?
Oh, and heres another short vid on the movement of the carriage at the end of the record. It really is soooo smooth. Getting to like this arm more. I played another few records tonight that I always got distortion towards the end of side and they play cleanly now. Thats a result.
http://www.youtube.com/watch?v=ezf7j37s44w
Sorry about the poor camera phone quality but you get the idea.
Fran
Mine is more or less the same except that I put the pivot points further away from each other (ie the cross piece is longer). I used ordinary kitchen knife because I thought the stanley knife blades were very brittle and thin and could chatter. Although it looks like thats what Mr. Terminator uses.
I wonder what a little silicone grease on the pivots would do?
Oh, and heres another short vid on the movement of the carriage at the end of the record. It really is soooo smooth. Getting to like this arm more. I played another few records tonight that I always got distortion towards the end of side and they play cleanly now. Thats a result.
http://www.youtube.com/watch?v=ezf7j37s44w
Sorry about the poor camera phone quality but you get the idea.
Fran
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