My indispensible tool (a variation on a FB theme)

[texman]

Re: My indispensible tool (a variation on a FB theme)

after several versions of my IT, i would offer this advice on design:
1. Make certain that the IT shaft is centered where it contacts the brick
2. Make certain that the clamp positions the brick perpendicular to the shaft vertically and horizontally
3. It is very useful to have the IT lock on horizontal plane
4. Make the pivot point as close as possible to the oven floor (no large casters)
5. Lock the whole apparatus in place so it cannot move once you start your dome
6. TRUST the IT! If it indicates an adjustment is necessary on a dry fit, believe it.
FWIW
Texman

[Amac]

Re: My indispensible tool (a variation on a FB theme)

Texman- agree with most of those with the possible exception of

4. Make the pivot point as close as possible to the oven floor (no large casters)

I don't think it makes any real difference about the centre being off the floor a bit. It means only that the dome is that much higher.
It has also a minor advantage in that the dome side walls are vertical for that extra distance.
I raised the centre off the floor by 1.5" deliberately so that the dome would match exactly the entry arch I wanted.
Aidan

[deejayoh]

Re: My indispensible tool (a variation on a FB theme)

I only think it matters if you want a low(er) dome. I was thinking there's probably a design where you could remove your center floor bricks and have a recessed IT, if you really want a low dome design

[cnicholson]

Re: My indispensible tool (a variation on a FB theme)

- I was thinking there's probably a design where you could remove your center floor bricks and have a recessed IT-

My design exactly. I'm using splits throughout the oven so I have a 2 split deep floor and I mounted the IT to a piece of plywood the exact same size at a brick. I do wedge it in place with a couple business cards and it has an allthread adjuster as well but I needed to be able to have one floor set and be able to mark the other level on top. It seems to be working well at the moment and I'll give some feedback when I'm done with the dome!

[mrchipster]

Re: My indispensible tool (a variation on a FB theme)

I used sailors for my first three chains and I do find that my peel will sometimes catch in the joint at the floor level. One thing I would recommend for people building their floor inside of the dome is to start with a chain of splits an then put a full thickness brick chain, that way there. Is not a seam at the same level as the floor. This does not happen to people who start with soldiers as the brick is taller than the floor.

Chip

[cnicholson]

Re: My indispensible tool (a variation on a FB theme)

That is an excellent point Chipster... saved me from making a mistake right there!

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

Thank you all who have contributed to this IT thread.
Here's notes on my version based the comments in this thread.

All of the parts I used came from Home Depot for ~$20.
This was a very efficient, inexpensive version if you have access to a welder.
I didn't end up using the castor shown in this pic as I didn't like how high the pivot point sat from the floor.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

Rev 1 swivel base was a caster w/ the wheel removed.
The caster pivot point ended up being too high.
This would have caused the top of the dome to be too high and and the dome slightly egg shaped.
Although it would have been unnoticeable, I wanted to come up w/ a better solution.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

My Indispensable Tool rev2.
I created the final swivel base by welding 2 flat washers together to a bolt head that I cut to the proper length.
This worked well by keeping the pivot point very low to the floor.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

My Indispensable Tool rev2.
I created the final swivel base by welding 2 flat washers together to a bolt head that I cut to the proper length.
This worked well by keeping the pivot point very low to the floor.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

My Indispensable Tool rev2.
View from bottom side of .5" plywood which served as IT base.
Threaded bolt locks into this plate from top side.
Cover plate prevents spinning arm from scratching firebrick.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

My Indispensable Tool rev2.
View from top side of .5" plywood which served as IT base.
A cotter pin held the pivot point in place, which was the end of a long nut that I drilled a hole through for the pin.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

My Indispensable Tool rev2.
View from back of pivot arm base which was created by welding 2 flat washer together to a threaded bolt.
A cotter pin held the pivot point in place, which was the end of a long nut that I drilled a hole through for the pin.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

My Indispensable Tool rev2.
Finished product, this worked very well for the entire dome portion of the build.
The 3 wooded legs are attached to the base by hinges to allow for removal of the IT.
Each of the 3 legs has a threaded pad installed in the end to allow each leg to lock against the base of the dome to hold the IT in place and centered throughout the build.

[boylanta]

Re: My indispensible tool (a variation on a FB theme)

My Indispensable Tool rev2 in action.
I ended up not using a clamp at all through my build.
I found that by holding the brick securely in place w/ my hand, then placing wood shims on the back side that the brick was locked in place.
I applied the mortar, then placed the brick in the IT, then shimmed the back, and added more mortar if necessary.
By time I got a few more bricks done this way, the mortar had set enough to remove the shims and fill the gap left w/ mortar.