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Member Since 16 Mar 2013
Offline Last Active May 17 2017 10:49 AM

#66929 What Is The Best Book In Your Pottery Library?

Posted by MichaelP on 30 September 2014 - 10:31 AM

One more vote for "Clay: A Studio Handbook" by Vince Pitelka. No BS, clear and logical explanations and suggestions.

#66752 Skutt Model A Wheel Used

Posted by MichaelP on 27 September 2014 - 11:48 AM

all belt driven, we will pass...

Why? Belt drives, by definition, are much more simple (=reliable) than gear drives, very inexpensive and easy to repair and, with all probability, less noisy.


Many types of machinery benefit greatly from using gear drives, but a pottery wheel, esp., an old one, is not one of those, IMO.

#51792 Is It Possible To Take A Mold From Ice?

Posted by MichaelP on 06 February 2014 - 12:11 AM

Ask your friendly dentist for a light body impression material.

#50662 Chamois For Cars Also Good For Clay?

Posted by MichaelP on 21 January 2014 - 12:10 AM


Would it fit in that guy's mouth? Too small?



Not absorbent enough to soak up all  his BS.

#49056 Diy Kiln Vent

Posted by MichaelP on 31 December 2013 - 04:26 PM

I just want to share a few photos of my kiln vent project.


The pin and its bushing were machined out of mild steel. The round foot - aluminum.

I didn't machine the circular top collar: I just found it in my scrap bin and used "as is" (the holes drilled in the collar do not interfere with its function, so I just left them alone).


I used the vent during several firings, then sandblasted the newly formed rust away and painted everything to finish the project. The pin was not painted. I blackened it to protect against rusting (it was heated, and used machine oil was rubbed into the surface). It looks like rust on the photos, but it's not. The inside of the bushing should be done the same way.


As you can see, magnets are used to regulate fresh air intake.


P.S. If I ever make one again, I'll use aluminum or stainless steel for everything (except the connection to the galvanized exhaust). Naturally, I'll have to make some kind of shutters instead of magnets then. This would require no painting and won't rust.

Attached Files

#42270 Studio Tools?

Posted by MichaelP on 08 September 2013 - 10:17 PM


Wakizashi or tanto are better tools for seppuku when you can't stand the shame of not knowing the words. (I no longer have access to smileys...... or any of the post editing tools?????)


#42247 Studio Tools?

Posted by MichaelP on 08 September 2013 - 11:27 AM

Then I read your post in another topic, about you being a iaidoka.

I've never heard this word, so after reading your post I google it. One of the first links says: "...iaidoka will usually use bokken for such kata practice".


Now the term is crystal clear to me. :) I'm going to use bokken next time I kata piece of clay.

#41898 PID Controller Programming. Cone 05 Bisque and Cone 5-6 Glaze Firing Schedules

Posted by MichaelP on 02 September 2013 - 01:36 AM

Here is something else that can be helpful to program Cone 5-6 in digitally controlled kilns. This is a way to emulate Cone Firing while making a custom program in Ramp and Hold Mode of Skutt and other controllers, including PIDs.


Choose the rate of the temperature increase during the last 200F of firing and see what temperature your kiln should reach to achieve Cone 5, 5 1/2 or 6. Each graph corresponds to one of the Cone #.


This is based on the data provided by Orton for self-supporting cones.

Attached Files

#36780 Aus potter in USA for workshop

Posted by MichaelP on 11 June 2013 - 08:42 AM

and yes, I'm an old lady too (50!)

Did you really need to ruin my day by calling a 50-y.o. person old? :(

#36755 Firing a lidded box

Posted by MichaelP on 10 June 2013 - 09:34 PM

I decided to drill holes in the bottom of the plaster cast and had to go to the emergency room when I drilled a hole in my foot

I can imagine the hysterical laughter in the ER when you told them what had happened. Posted Image

#36538 What Every Potter Needs!

Posted by MichaelP on 06 June 2013 - 11:05 PM

I bet they used splash pans! :)

#36406 PID Controller Programming. Cone 05 Bisque and Cone 5-6 Glaze Firing Schedules

Posted by MichaelP on 03 June 2013 - 09:38 PM

I'd like to post my notes on programming a simple Ramp and Soak PID temperature controller for Bisque (Cone 05) and Glaze (Cone 5-6) Firing. The Glaze Firing Schedule was adopted from the book "Mastering Cone 6 Glazes" by John Hesselberth and Ron Roy. The Bisque Firing Schedule is based on suggestions found in many books and other sources of information.

Note that the controller is programmed in Celsius. The controller operates an SSR (Solid State Relay) which switches the kiln on and off (Note: if you use a mechanical or mercury relay, use Cycle Time value from 20 to 40 instead of "5" in the PID setup).

My controller is capable of programming 50 steps. I allocated steps 1 through 7 for Bisque Firing program and steps 15 through 21 for Glaze firing.

I hope someone may find these notes helpful for setting and programming his/her own PID controller.It'll be quite easy to substitute the temperature and time values if you want to change the curves.

Attached Files

#36342 What is this Wheel Worth?

Posted by MichaelP on 02 June 2013 - 06:05 PM

OK i wll give you a hundred bucks ifyou include the guy sitting at it, I can always use a slave..... T

Being kinky?

#33859 Making a hole in a kiln for thermocouple

Posted by MichaelP on 30 April 2013 - 08:38 AM


Thank you for your suggestions. I finished the installation last night. It was really easy and uneventful. For the completeness sake (in case other people find it helpful), let me describe the procedure.

I installed my thermocouple at, roughly, the same level with the Sitter, but on the adjacent wall. My peep holes are to the left of the control box, and the thermocouple is to the right of it.

I measured the distance between the upper rim of the chamber to the midpoint of a brick, transferred the measurements outside and drilled from the outside in. Before drilling, make sure the termocouple is not going to be at the same level as your shelf when the shelf is rested on your posts. This will keep the thermocouple away from the large mass of the shelf that heats and cools slowly and may therefore affect reading.

A smaller pilot drill was followed by a 15/32" drill. As always with drilling stainless steel, you need to use slower speed and a sharp drill (preferably, with a 135 degree point) and apply definitive pressure so that the drill grabs the metal right away. If you rub the drill against stainless steel, the drill will dull, stainless steel will work harden and make further drilling much more difficult.

Then I inserted the thermocouple with a nice reasonably tight fit. A made it so that it protrudes into the chamber a healthy 1 3/4" (approximately, as much as the Sitter does). Then I tried inserting a kiln shelf to check if the thermocouple doesn't interfere with its insertion. Such a significant protrusion of the thermocouple will insure a more true temperature reading. Besides, it played well with the lengths of the thermocouple insulation rings (by the way, I needed to remove two one them to fit my wall thickness). Then I attached the thermocouple to the terminal block to mark the block holes location and took the block away. Then I drilled very small holes and re-attached the block with sheet metal screws. Finally, I cut extra protruding thermocouple wires using an angle grinder with a cutting wheel attached.


This is a permanent installation to automatically control firing cycles. I did use peep holes for taking occasional temperature readings before though. But thank you for your suggestion anyway.

#33833 Making a hole in a kiln for thermocouple

Posted by MichaelP on 29 April 2013 - 08:05 PM

I'm in the process of finishing a DIY programmable controller box for my kiln. The kiln has the Sitter, and I'm not going to make any changes to the kiln. However, I need to install a thermocouple, so drilling a hole for it will be my next step. The kiln is an Evenheat 18"dia x 20" octagonal one. It has a stainless steel outside shell and 4"-high extension ring.

First, I thought about drilling a hole just below the Sitter cone holder. Then I decided not to attempt getting inside the control box and, instead, drill a hole in the ajacent wall. It would be easier to drill the lid, but I don't think measuring temperature on the top where it's higher is a good idea (no downdraft vent yet). Yes, I can make adjustments, but I'd rather know the actual temperature in the middle of the kiln (approx., the Sitter cone level). Besides, the lid is not covered with a metal shell, so attaching terminal plate to it will be very problematic.

Have you ever done it? What area did you choose for the thermocouple?

Did you use any refractory compound to seal around the thermocouple's insulation rings or went with just a reasonably close fit? I think sealing the space around is not a good idea since the thermocouple may need to be replaced at one point.

What are your thoughts, ideas and hints? It sounds like an easy and very straight forward procedure, but it's always better to get a second opinion. :)

Thank you.