Hendo's dome gauge -- nice idea

[mirassou]

Here's one for sale on ebay from one of the forum members. I didn't elevate mine. I mounted it to a thin piece of hard board that I made round to protect the oven floor. Somewhere on here were the plans for it. It's cut in half to be able to remove it through the door after completing the dome.

[Annie2]

(Essay No 33⅓)

Dome gauges ? there are many ideas out there ? perhaps the simplest, a bit of wire fixed by a screw or nail to the centre of the cooking floor.

For my project, the centre of the cooking floor for some reason did not coincide with an intersection between bricks. I was concerned that if I drilled a hole in the centre (close to the edge of a brick), it would lead to a chipped corner, and I had had enough of those laying the floor (too heavy handed with the rubber mallet!).

So I decided to:

1. put down a temporary MDF floor to assist in laying the first ring of bricks at the correct diameter;
2. fix a ball/socket joint to the centre of the MDF floor;
3. fix a dowel/rod setup to the ball joint like other members have recommended to test for correct diameter, course by course.

After many sleepless nights, I came up with the idea of using a photographic tripod ball head, fixed upside down to the MDF with a barbed T-nut, and a ?dowel? fastened to the ball head by an appropriately threaded bolt.

But what threads do tripods use, you may well ask? It's a choice of Metric (France, Germany etc) or Imperial ? probably Whitworth (BSW) at a guess. Now I?m no betting man, but I would have thought that the first person to design a camera tripod mount would have been Continental (ie a metric thread), rather than a Brit or American. But wrong! The threads on the tripod mount are either ?? (more common) or ⅜? BSW. So I?ve learnt yet another thing during the course of this project. I daresay it could have been George Eastman who decided on the thread, and camera tripod mounts will consequently be the same forever!

So I purchased a ⅜? bolt and ?? T-nut, drilled out the end of a scrap piece of timber and glued the bolt (after decapitating it) into the end. A few quick calculations led me to realise that I had to compensate for the height of the ball head centre above the floor, so I rigged up a system of a packer (for slope) and end stop (for internal diameter) to check that I?m doing things more or less correctly. The only problem is that both the packer height and end stop distance must be altered each course.

Pics below are self-explanatory. And yes ? I know, don?t tell me ? the ancient Romans would not have done it like this ? but I?m inexperienced. Well at least I chose an Italian ball head! If it survives the build, it will deserve pride of place on my new tripod!

Cheers, Paul.

Its a good suggestion.

[WayneH]

Re: Hendo's dome gauge -- nice idea

As a newbie about to venture forth into the art of purist pizza oven constructiion this little gem has done two things with out even having lifted a brick... firstly justifying hanging on to that old tripod with dysfunctional leg locks ... and secondly solving the "where to find scrap material that will make a good dome guage" question...

Thanks muchly... now i'm off to pick a fight with some bricks !!!

Wayne - Durban South Africa

[Campmaki]

Re: I Did It My Way! ? Hendo?s Dome Gauge

Paul - I believe there is a saying "Necessity is the mother of all invention". Very clever! For those that take this approach, you can purchase an in line ball joint for around $4.00 at this site. Keep your tripod in one piece so you can take pictures of the build

McMaster-Carr

Les...

Les, thanks for your post, I purchased ball and socket parts from this place.

[mirassou]

Re: Hendo's dome gauge -- nice idea

I have an IT that I'm done with now and had gotten from Kurtloup and made some modifications, so if anyone wants it, please message me privately. It doesn't come with the angle tool, but I recommend buying one from Lowes.

[oasiscdm]

Re: Hendo's dome gauge -- nice idea

Dennis

Dennis

I agree I found this on the first and second course on my oven However I was using arch bricks variable profile, to minimise gaps and end with almost finish, doing a flatter dome, so needed the adjustable IT worked a treat to avoid this.

But with a fixed hemisphere Dennis is completely right so pay attention

[deejayoh]

Re: Hendo's dome gauge -- nice idea

I have been wondering why so many new builders come up with the idea of making an IT where the pivot rod hits the brick at the top. I finally decided to see what the sticky suggested and VOILA! I found that these directions on how to build an IT are INCORRECT

All credit to Hendo for coming up with the first design on this - but many of us have found the flaw with this design. An it built this way will result in an oven with each course staggered backward a bit from the previous one. This is because each brick is slightly off axis to the pivot, as the brick is not centered on the pivot.

Here is an example from a thread I saw today


Here is a graphic explaining taken from another thread


To work properly, the IT pivot rod needs to hit each brick in the CENTER (measured from top to bottom). This will give you a smooth radius to your dome


/rant

Dennis

[waikato pizza]

Re: Hendo's dome gauge -- nice idea

Just thought I would also share my design as it has been brilliant and robust. It is also adjustable if you need to, say for supporting those funny fill in bricks around a chimney or something.

Hope it helps someone

http://www.fornobravo.com/forum/f28/...ope-18895.html

As you will see I have been reusing materials from an old chimney in a bid to be "slightly eco" and this has been invaluable.

All the Best - Andy

[1critter]

Re: Hendo's dome gauge -- nice idea

I am a newbee here, this is a valuable piece of info. for me.
Thank You
Ric

[joepierce1988]

Re: Hendo's dome gauge -- nice idea

Very nice and original idea.

[jmhepworth]

Re: Hendo's dome gauge -- nice idea

Great idea. More pictures.

[backinoz]

Re: Hendo's dome gauge -- nice idea

Thought I would share my variation of the indispensable tool with what I think is the next step in innovation.
For the universal joint I have used a magnetic door stop from the local hardware store. The shaft is made from some dowel and it all screws together. The advantages for this design is

• Able to be constructed with no welding
• Allows infinite accurate movement in all directions without sticking or catching that you would get with hinges or wire
• The end has a spring so if clearance is required the spring will allow ~2-3mm clearance
• Can be removed easily at the end of the day or to attach a pen etc. Can be removed without getting into the oven.

The base just screws to the plywood in the oven. (more pictures when I start)

[SCChris]

Re: Hendo's dome gauge -- nice idea

I've been mulling over this tool and how I'm going to build it. I'm going to prototype a tool made from a lazy susan, 2 models are available at Lowes. Look for Waxman and lazy susan. It's not a great advantage to have the bearing, but that for $6 to $10 I have 360 degrees covered. Next by connecting a horizontal rod across the upper, free, rotating plate I can cover the pivot for the vertical changes. I'm leaning toward a threaded hoizontal rod with aircraft bolts to attach it to L brackets at the edges of the lazy susan and two more to bracket the rod at the center point that sets the radius. So this part of the unit in the end is like a universal joint on truck. Mount the whole thing to plywood or masonite or whatever you need to to have a steady, non moving base.
Comments?

Chris

[geisen]

Re: Hendo's dome gauge -- nice idea

PHIPHAM
Hendo's gauge was inspirational and spawned many a great dome.
I am currently using one of the Hendo gauge offspring that takes his great idea and improves on it with a clamp to insure each brick's distance AND angle is perfect.
Check it out at:
http://www.fornobravo.com/forum/f28/...heme-2985.html

It has made the dome a no brainer (perfect for me).
Also using "the angleizer" to take the brain work out of the arches.
Availble at HD, see it on my thread.
Good luck.
Regards
Greg

[Frances]

Re: Hendo's dome gauge -- nice idea

I got the same effect using a rotating hinge in the middle of the cooking floor.

I'm sure the pics will come up again if you check back - I couldn't see any yesterday either...