Here is a list of all the postings John Rudd has made in our forums. Click on a thread name to jump to the thread.
Thread: Amadeal VM25L R8 Milling Machine |
23/06/2022 16:53:38 |
Nice try.....now to address the over hang, you could make some machinists jacks that would fit underneath the bar at either end....
A job for another day... |
Thread: Help Needed - Reversing a 240 Volt Motor |
18/06/2022 09:30:19 |
Edited By John Rudd on 18/06/2022 09:33:32 |
Thread: High temp varnish |
17/02/2022 12:55:57 |
Duncan, You could use varnish as used for transformers and motors from Brocott.co.uk
https://brocott.co.uk/electrical-insulating-air-drying-varnish-250ml-clear/ Good for temperatures in excess of 100C and they sell in small quantities… Edited By John Rudd on 17/02/2022 12:58:07 |
Thread: (Another) Mini Lathe Speed Controller Problem |
17/02/2022 10:55:29 |
Posted by John Haine on 17/02/2022 09:37:23:
Motor controllers don't necessarily react happily to the circuit to the motor being interrupted whilst running, your fuse could be a bad move...
|
15/02/2022 21:34:31 |
Philip, I sent you a private message.
IanP, The description of the controller discussed in the article is based on a PWM based controller using mosfet power devices rather than the KB clone which is Phase angle control using a pair of scr’s in a full wave bridge. |
Thread: Help wanted, DC motor speed controller issue |
31/01/2022 14:50:55 |
Russ,
The following notes might aid your fault finding... The component designations are for a KB controller, they may be different to that of the Best item...
(A) Check resistance across L1 and L2. Reading should show infinite or open circuit. Be sure to reverse leads across L1 and L2. Reading should still be infinite. Measurement values shown below are approximate only . |
27/01/2022 13:08:41 |
The Chinese lookalike boards similar to the KBIC control boards are essentially copies using thru hole components, although some later derivatives use smd devices too. The mains AC is used to drive a full wave bridge rectifier comprising 2 S*025L thyristors and similarly rated diodes.A third diode is connected directly across the output. The F+ and F- supply is generated using two low current diodes( typically around 1 amp). The full wave bridge uses phase angle control with a zero crossing detector to generate the speed control. A startup ramp is generated using a resistor and capacitor network that is adjustable to give a soft start, current overload sensing and motor load compensation is also featured on these boards. The Seig speed controllers are similar but principally operate the same way.( are some subtle differences in how the 12v rail is provided). Repairing these boards is not for the faint hearted. Fake parts abound, beware where you buy replacements from Edited By John Rudd on 27/01/2022 13:09:11 |
Thread: Smart meter |
21/01/2022 14:15:39 |
Posted by duncan webster on 21/01/2022 13:56:30:
Taking meter readings every month is not exactly onerous, and I know tumble driers use a lot of power, so I still don't see why smart meter is to my advantage…..l Smart meters in my opinion do not help the consumer more like confuse….,
Its simple, you pay for what you use….If you live in a household lit up like Blackpool illuminations, then be prepared to pay a large bill….. When I was a child, we were reminded, to close doors behind us and turn off lights on leaving a room….now as a bill payer I can see why… |
Thread: SPG Tools in Hinkley |
09/01/2022 18:20:29 |
http://www.sumore.com/english/cplist.asp?type=2 Edited By John Rudd on 09/01/2022 18:21:16 |
Thread: SMR's a conundrum. |
08/11/2021 11:44:37 |
I used to hate TLA's when I was working.... Thought I'd seen the end of them... |
Thread: Chester 920 cross slide & Backlash |
29/10/2021 16:52:15 |
I bought my spare belts from Beeline engineering in Milton Keynes, they worked out to be about £6-7 ea..much cheaper than the likes of Warco/Chester or even Ebay
The belts themselves are 5mm wide, the length did vary with machine....730 seems to stick in my mind... Generally, If you have a 160XL Coged belt, you need a 5M720 V-Belt. Edited By John Rudd on 29/10/2021 16:57:24 |
Thread: Selection of AC transformer for Align Power Feed |
23/10/2021 10:08:08 |
Go to your local electrical factors and ask for a 240-110V AC control transformer....
Dont know your location but here's an example....
https://www.rselectricalsupplies.co.uk/chint-multi-voltage-panel-transformer-150va-ndk150_1068
|
Thread: Chester 920 cross slide & Backlash |
15/10/2021 08:39:38 |
The cross slide lead screw is M8 with a lh thread. I had to make a new one for my 9 x 20 when the original snapped...Silver steel is good enough for a replacement.. |
Thread: Sieg X2 mini mill blowing fuses |
21/09/2021 21:33:26 |
David, I sent you a private message....disregard it if the mill is new and under guarantee... the power semiconductoir devices are thyristors ( scr ) and form part of a full wave rectifier bridge across the mains...one or more is defective if you read 0 ohms... |
Thread: Cutting Steel Plate. |
11/09/2021 12:00:06 |
Posted by John Baron on 11/09/2021 11:36:11:
Posted by noel shelley on 11/09/2021 10:18:29:
Sounds like fun ! Where are you ? Noel Hi Noel, I'm in North Yorkshire, near York.
You arent cutting up the 'lightning struck' Bilsdale tv mast are you?
|
Thread: Vfd frequency Warco WM290 and WM280v |
30/08/2021 15:23:09 |
FWIW,
I have a similar machine to the WM290 which originally came with a dc drive. I changed the motor to a 2 pole 2800rpm 1.1kw 3 phase motor in an 80 frame size, it occupies the same space as vacated by the dc motor. I used an Invertek vfd and set the max frequency to approx 72 Hz to give me the same spindle speeds as before. I had no need to change belts or pulleys. I used the existing speed control pot, rewired the FWD/REV switch to give the desired functionality for the vfd. No additional switches or buttons. |
Thread: re-magnetising magnetic base |
07/07/2021 15:08:28 |
Folk who offer magneto winding services may be able to remagnetise it for you… |
Thread: Is this a new scam? |
30/04/2021 20:05:38 |
Selling on Ebay has now become less attractive....Gone are the fees paid to Paypal because the buyer pays directly to Ebay and they in turn pass on the proceeds to the seller after taking their cut... From what I can gather Ebay fees are now more than what Paypal would have charged plus the selling fee for Ebay combined...making it less attractive to sell a low value item inc postage. As a consequence of this, even buying would be less attractive too because sellers are likely to increase their prices to accomodate the rise in fees. |
Thread: Variable rpm control for watchmakers lathe |
19/03/2021 12:32:27 |
John Fletcher, pm sent...please. |
Thread: HydroVane PR303E question |
15/03/2021 15:34:05 |
I asked him "what work exactly has been done to this compressor as it is described as 'seller refurbished', did you use any spares?" (potential for mis-selling, not as described)
It wouldn't surprise me if it didn't sell....
Just got a reply on the instructions...£20....Greedy!! Edited By John Rudd on 15/03/2021 15:41:10 |
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