Who is interested in a groupbuy of Mark Kelly's DC controller PCB and related parts - Page 13 - diyAudio
Go Back   Home > Forums > Commercial Sector > Group Buys

Group Buys Members group buys

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 28th April 2006, 05:50 PM   #121
diyAudio Member
 
Join Date: Jan 2003
Location: Musicville
Quote:
I've talked to machinists and they say it is impossible to make the pulley and then drill the hole perfectly centred. It must be done by small parts machine maker in one step process- hole and CNC body together. Also the hole must be slightly tapered to press fit.
First off, you'll never ever achieve concentricity by simply drilling a hole in the pulley, no way it'll happen, nor will it control the size of the hole.
The statement is correct in that the motor shaft hole and body must be machined in 1 step. This will offer the best chance for concentricity. But you have to go 1 step further and actually bore the hole, reaming will control the size but will not obtain the best concentricity results. A reamer only follows the path of the existing hole.
I know there are shortcuts and a lot of manufacturers use them because I've seen those results.
IMO, you drill then finish bore the hole for best results so find someone willing to do that and you'll get a nice pulley.
Tapering the hole is an easy way to get a press fit but not good practice in this application, YMMV.
  Reply With Quote
Old 29th April 2006, 02:57 AM   #122
diyAudio Member
 
Join Date: Feb 2006
Location: Willy, VIC
Default Re: am I too late

Quote:
Originally posted by robbie
Hi All
am I too late to join this?

but before I send any money can I check some things.
am trying to upgradee my PTTOO using the ironless motor from permotec (rs no - 432-9765 ) but have been using a very simple variable voltage circuit.
will this kit work with this motor?

thanks
Rob
Kinda

The specs on the RS website are pretty sketchy but by dividing the no load speed by the voltage we can derive an approximate speed constant of 320 rpm per volt. The torque constant is given as 29 mNm per amp, dividing the speed constant by this gives around 11 rpm / mNm.ohm.

Dividing the no load speed by the stall torque gives us an approximation for the speed / torque slope at about 130 rpm / mNm, divide this by the ratio between the speed and torque constants gives a terminal resistance around 12 ohms.

This motor will work with my drive but not as well as the motor for which it was designed. I also wouldn't use it below 600 rpm.
  Reply With Quote
Old 29th April 2006, 11:46 AM   #123
robbie is offline robbie  United Kingdom
diyAudio Member
 
robbie's Avatar
 
Join Date: Mar 2003
Location: south coast
Default thanks

thanks for the reply Mark.
could I be pointed in the direction of something more suited to the premtech motor.

Thanks
Rob
__________________
Try anything twice - just to make sure
  Reply With Quote
Old 2nd May 2006, 01:24 PM   #124
diyAudio Member
 
Join Date: Feb 2006
Location: Willy, VIC
I have received the second prototype PCBs, built and tested them. I will place orders for all parts tomorrow. Bas, how many confirmed participants do we have?
  Reply With Quote
Old 2nd May 2006, 01:54 PM   #125
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
pcb parts
arad 1 0
Bas Horneman 2 1
zum911 1 1
Lord Dubious 1 1
sklimek 1 0
Kevinchampion 2 2
dod996 2 0
markgall 1 1
Tonyb 1 1
Matt Rowland 1 1
john2 2 1
astro_nut 1 1
Seth Hensel 2 2
DaveM 1 1
Michi124 2 2
Gypsielectro 1 1
Robbie 1 1
superhkm 2 2
Diyfan 1 1
Patriz 10 0
cwise 2 2
werner 2 0
leadbelly 1 0

pcb: 41 parts: 22

Hi Mark,

These have given me their paypal address which I will forward to you. One has confirmed interest but had no paypal account. I asked him to contact you personally.

Cheers,
Bas
  Reply With Quote
Old 2nd May 2006, 02:15 PM   #126
diyAudio Member
 
Join Date: May 2005
Location: oslo
I thougth I sent you my info Bas.. did I dream it ? I'll check when I get home.

hk
  Reply With Quote
Old 2nd May 2006, 02:17 PM   #127
diyAudio Moderator Emeritus
 
Bas Horneman's Avatar
 
Join Date: Apr 2002
Location: The Netherlands
Blog Entries: 18
Oeps...Yes..sorry..I had not labeled your email.
  Reply With Quote
Old 2nd May 2006, 06:03 PM   #128
we416b is offline we416b  Canada
diyAudio Member
 
Join Date: Aug 2004
Location: Niagara Peninsula
Hi Mark,
I'm the one who won't get another paypal account. (See my April 18 post for explanation.) Can I pay you directly with a US$ money order?
Thanks,
Fred
ps I've tried to contact you directly through various boards and through Quiddity, but with no success.
  Reply With Quote
Old 2nd May 2006, 08:40 PM   #129
john2 is offline john2  United Kingdom
diyAudio Member
 
Join Date: Aug 2004
Location: lanc
Sorry,
Could I increase my order to 2 sets of boards(4 in total)-please? Spare boards in case of a burn up, or other unforeseen problems.
If I am too late to increase my order-don't worry.
Many thanks.
  Reply With Quote
Old 2nd May 2006, 11:26 PM   #130
diyAudio Member
 
Join Date: Feb 2006
Location: Willy, VIC
OK I have ordered sufficient parts for the orders I have plus two spare. If you're not "on board" yet (sorry) but are still interested, let us know.

I will put the paypals through when I am ready to ship - the board house says 6-8 days but last time it took an extra 6 days to get here.

I vote we all owe Bas something for his efforts in getting this up and running.

Quote:
Originally posted by we416b
Hi Mark,
I'm the one who won't get another paypal account. (See my April 18 post for explanation.) Can I pay you directly with a US$ money order?
Thanks,
Fred
I'm not sure about the postal order, they are fairly expensive to cash. How about you contribute $20 to DIYaudio on my behalf and we'll call it quits.

Quote:
Originally posted by john2
Sorry,
Could I increase my order to 2 sets of boards(4 in total)-please? Spare boards in case of a burn up, or other unforeseen problems.
If I am too late to increase my order-don't worry.
Many thanks.
I had you down for one full set (boards and parts). If I read you correctly you now want two sets of boards and one set of parts.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 08:42 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2