Did you contact them or just use the automated system? Their Terms and Conditions document says they accept credit cards on outside of the US orders if I'm reading it correctly.
I have exchangee multiple mails with on of their customer representatives. Mails are always very short, scarce on details and cover usually one of several questions I ask so I have to repeat the mails.
Might be a busy season for them. Might be my order of several motors is to small for them to accomodate.
I came across some cheap off the shelf pulleys that I'm considering:
Standard grooved
Precision grooved
If I'm not screwing up my calculations, an 0.75" OD would need to run at about 533 rpm when driving a 12" platter (actually a little faster, since the bottom of the belt groove is a slightly smaller diameter). Pretty close to the 600 rpm the BLWS motors are said to be quietest at.
I'd take a punt on the standard version, but the 0.75" OD one is out of stock with an 8 week lead time.
Few questions for any more mechanically minded than myself:
Standard grooved
Precision grooved
If I'm not screwing up my calculations, an 0.75" OD would need to run at about 533 rpm when driving a 12" platter (actually a little faster, since the bottom of the belt groove is a slightly smaller diameter). Pretty close to the 600 rpm the BLWS motors are said to be quietest at.
I'd take a punt on the standard version, but the 0.75" OD one is out of stock with an 8 week lead time.
Few questions for any more mechanically minded than myself:
- Is there any benefit to the clamp type hub over a pin type with a set screw? I guess the clamp type would be balanced better, but would that matter?
- The precision pulley's bore is specified as 0.2498" +0.0005/-0.0000, while the BLWS motor's shaft is specified as 0.25" +0.0000/-0.0005. Is there any likelihood of having problems getting the pulley on the shaft? If they were both dead on spec would the 0.2 thou of interference cause problems?
- Does anyone know what the "spot drill" and "sub drill" holes are for? I'm guessing they're for the user in case they need to put in another set screw at 90° to the first, so they don't have to locate and start the hole themselves?
I'm not sure the clamp type would be more centric (self-centering?).
If anything, the center bore should be at least 0.0003 oversize, not undersized. Even with a 0.0003" oversize bore and Delrin/Nylon material, it will feel "snug". With a brass undersized bore, I would think you will need to heat the pulley and cool the shaft (with freon) and it will still need to be pressed on. Good luck trying to remove it.
I've been loaned a Unimat micro lathe for awhile, and have been experimenting with making my own pulleys. The results so far are looking good. They seem to run true, and are snug enough on the shaft to not require a set screw. I might add set screws anyway, but I need to set the Unimat as a mill first.
Attachments
It averages out to approximately 1 step of the built-in digital attenuator for every 1 Hz of frequency change (reduce the voltage as the frequency goes lower, increase voltage as frequency goes higher). Below 10Hz, the relationship is no longer linear and needs to be measured for each 1Hz change in frequency.
I charted the voltages from 1Hz to 65Hz and the output voltage to the motor should be 8.16VRMS to 23.4VRMS respectively.
I received the pulleys (ordered a 1/2", 0.75" and 1" for mucking around purposes) mentioned in my earlier post- can report that the standard delrin on brass versions fit the shaft nicely. They require a tiny bit of pressure to get on, but once on there's no play that I can detect, and snugging the grub screw is all that's needed to stop any slip or axial movement.
Motor shaft Pulley
Gentleman, May I offer my services in machining These motor pulleys?
I have small precision lathe with adjustable Head stock bearings for very very round parts, remember these parts are only as good as your headstock bearings!, no engine lathe is good enough
Things I require are simple dimensional drawings "imperial" dimensions please,
another would be the actual Motor's themselves or the motor shafts, so i can make exact fit, no measuring tools will do, I have small bore gage's but not reliable enough, I have dial bore gage but way too big for this use. once I make and size the part, I can make up my own go no go pins and return the motors or shafts.
but I digress NOTHING is perfect but I can get as close as possible
to contribute to this fine cause , my only requirement a complete setup for myself possibly to fit my stock TD 150 TT so you guys would have to work it out for yourself's
I would make as many as needed
I have the time as i am between jobs at the moment and can spend a great deal of time and effort.
Lawrence
Gentleman, May I offer my services in machining These motor pulleys?
I have small precision lathe with adjustable Head stock bearings for very very round parts, remember these parts are only as good as your headstock bearings!, no engine lathe is good enough
Things I require are simple dimensional drawings "imperial" dimensions please,
another would be the actual Motor's themselves or the motor shafts, so i can make exact fit, no measuring tools will do, I have small bore gage's but not reliable enough, I have dial bore gage but way too big for this use. once I make and size the part, I can make up my own go no go pins and return the motors or shafts.
but I digress NOTHING is perfect but I can get as close as possible
to contribute to this fine cause , my only requirement a complete setup for myself possibly to fit my stock TD 150 TT so you guys would have to work it out for yourself's
I would make as many as needed
I have the time as i am between jobs at the moment and can spend a great deal of time and effort.
Lawrence
Thanks for your offer to help Lawrence.
There are generic drawings for the 2 pulleys here:
http://www.diyaudio.com/forums/anal...s-amp-diy-bldc-motor-drive-2.html#post5082457
There are 3D CAD files for the pulleys here:
http://www.diyaudio.com/forums/anal...s-amp-diy-bldc-motor-drive-3.html#post5082799
There are generic drawings for the 2 pulleys here:
http://www.diyaudio.com/forums/anal...s-amp-diy-bldc-motor-drive-2.html#post5082457
There are 3D CAD files for the pulleys here:
http://www.diyaudio.com/forums/anal...s-amp-diy-bldc-motor-drive-3.html#post5082799
Alright, need to study little more, I might have some other questions, Now I do not like the setscrews idea for the simple fact of de-burring the bore, its a simple solution, I get that but IMO an interference fit would be best, I would have to look this up in my machine hand book , but I understand if this set screw is what you want
making the tools 120deg should be straight forward, I wish they were 60 deg included angle as i have plenty of threading form tools
materials would need to be supplied of course and Delrin/acetal is best because of its dimensional stability plus it machines very nice good idea
I can also do one off if you need something special
Lawrence
Last edited: