3 Phase Class D amp for DIY BLDC motor Drive

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S

Sk8Ter

Member
Joined 2011
AVWERK said:
You might drill a hole on top and have access to the shaft as an interference fit ( best, but impractical for most) that proves to be slightly out of round , can be easily pulled off with a puller for correction purposes.

Regards
David
Click to expand...

Yes, I was just going to ask about this .3125" hole look at the drawing, unless there is a reason its there IMO a solid piece would deflect less, its cantilever effect.

Lawrence
 
J

JOHNNYCR100

Member
Joined 2010
Pulley registration of interest

Hi sirs,

If this pully gets off the ground may I please register my intrest as long as pricing is not to crazy, perhaps time to register intrest in a group buy if SK8Ter wishes to do so?

Best regards and thanks for all your efforts in helping us all.

Regards
Johnny
 
S

Sk8Ter

Member
Joined 2011
JOHNNYCR100 said:
Hi sirs,

If this pully gets off the ground may I please register my intrest as long as pricing is not to crazy, perhaps time to register intrest in a group buy if SK8Ter wishes to do so?

Best regards and thanks for all your efforts in helping us all.

Regards
Johnny
Click to expand...

I am not good at organizing this kind of thing, maybe someone can step in and help with this?


Lawrence
 
Pyramid

Pyramid

Member
Joined 2006
Sk8Ter said:
Yes, I was just going to ask about this .3125" hole look at the drawing, unless there is a reason its there IMO a solid piece would deflect less, its cantilever effect.

Lawrence
Click to expand...

The 5/16" bore was added because my machine shop that I used could not hold a 1/4" center bore accurate through the entire length of the pulley; the boring bar would deflect and the center bore would be out of round. The 5/16" plunge is not critical, but it creates a shorter length for the 1/4" bore which is.

The 1/4" bore length is approx the same length of the motor shaft that would be inserted into the pulley. Making it longer would not have any positive effect on deflection.
 
S

Sk8Ter

Member
Joined 2011
Pyramid said:
The 5/16" bore was added because my machine shop that I used could not hold a 1/4" center bore accurate through the entire length of the pulley; the boring bar would deflect and the center bore would be out of round. The 5/16" plunge is not critical, but it creates a shorter length for the 1/4" bore which is.

The 1/4" bore length is approx the same length of the motor shaft that would be inserted into the pulley. Making it longer would not have any positive effect on deflection.
Click to expand...

to your last paragraph, I agree but why so long rib area? this is what I was referring too, if you place the drive string/belt to the top(furthest from motor) then from the forces esp from plastics will deflect.

sorry if I am thinking too much, its my nature :)
 
R

rsritchey

Member
Joined 2012
Not to muddy the water any more, but I've been making pulleys with .25" bores that I intended to offer to the group. I'm not a machinist, but I've been chewing through a long section of Delrin, and I think the results are pretty good. I wanted to get a dial indicator to check them, but by eye at least they track true and sound fine.

Russell
 
S

Sk8Ter

Member
Joined 2011
rsritchey said:
Not to muddy the water any more, but I've been making pulleys with .25" bores that I intended to offer to the group. I'm not a machinist, but I've been chewing through a long section of Delrin, and I think the results are pretty good. I wanted to get a dial indicator to check them, but by eye at least they track true and sound fine.

Russell
Click to expand...

Have at it Russell, may I suggest to use dial test indicator in 10ths, millionths would be better :)

if you have good eyes your able to see about 2 thou runout.

I will leave you guys to it!

Cheers


Lawrence
 
R

rsritchey

Member
Joined 2012
Lawrence,

That's the thing. I'm unsure of the precision that I'll ultimately be able to accomplish, and as much fun as I've been having, the goal for the group should be the best pulleys they can get. In other words, I don't want to get in the way.

I've still got extra amplifier PCBs if you need one btw.
 
S

Sk8Ter

Member
Joined 2011
rsritchey said:
Lawrence,

That's the thing. I'm unsure of the precision that I'll ultimately be able to accomplish, and as much fun as I've been having, the goal for the group should be the best pulleys they can get. In other words, I don't want to get in the way.

I've still got extra amplifier PCBs if you need one btw.
Click to expand...

My sentiments exactly, I do not like to waist my time if others plan on doing to the deed, in short it's all good! :) if someone wants job shop type one off stuff, I am your guy.

now besides a dial test indicator you will need some V blocks and a hi precision ground rod to revolve around, drill rod could work for the test.

I also wanted to point out something most people WAY over exaggerate in building a TT for instance, your records that you will use will be 1000 times worse in every kind of way unless and even if you you plan on re-punching center holes, hold the record very tightly against the platter, the lathe cutting speed issues, tape recording speed issues etc. etc. manufacturing etc. there will be all kinds of runout eccentricity everywhere.

Guys records are an imperfect medium NOTHING is perfect in record/music reproduction. once you understand this you can relax, do the best you can IMO it will be hugely better then any record I promise you that. :)


carry on gents

Lawrence
 
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J

JOHNNYCR100

Member
Joined 2010
Help required with OSHA park magnetic sensor pcb

Hi'

Sorry if a bit off topic.... but I have gone cross eyed looking for the component
( and mouser ref numbers) for the surface mount components for the hall effect sensor offered via OSHA park PCB as I want to trigger a taco to show RPM

Namely parts ( p1/d1 d2/r1and q1) as denoted on the PCB

Can any kind soul point me in the right direction for ordering the correct parts ?
( from mouser if possible)

Best regards
Johnny
 
G

GaryB

Member
Joined 2002
Paid Member
The BLWS231S-24-2000 motor had been out of stock at Anaheim Automation but their website now shows that they've got 46 in stock. So go get them. I'm leaning towards this motor over the BLWR172S-24-2000, since the BLWS has a built in flange and at least person reported it being slightly quieter.
But the question of what pulley to use is still unclear to me. As reported by Jobst 3 Phase Class D amp for DIY BLDC motor Drive, the BLWS can used with an inexpensive pulley from Sterling Instruments Product | Designatronics Store | Stock Drive Products/Sterling Instrument, but it only supports a single belt. Several people have commented on better results with a double belt. The BLWR can be used with a 4mm-3/16" adapter OSE 4mm to 3/16" Prop adapter and then one can use a stock VPI pulley. That combination is more expensive and requires a mounting plate for the motor but doesn't need a custom pulley. But the adapters are currently out of stock.

So what's a DIYer to do? Is anyone picking up the challenge of making pulleys? I'll probably just go the BLWS route and us the Sterling pulley for now and swap it out later should some industrious person decide to have a batch made. Curious to hear what everyone else is doing.
---Gary
 
J

JOHNNYCR100

Member
Joined 2010
BLWR Motor prop adaptor (lack of)

hi boyz,

the OSE 4mm to 3/16" prop adaptor is out of stock at the supplyer suggested and has been so for some time, as an "expectent" BLWR motor owner i feel a bit high and dry on this one, a real shame as i dont know where to go from here with this project haveing got the rest of the electronics working:D

(i live in an "odd" place where there are no local machine shops in the vacinity)
what to do?)

regards
Johnny
 
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