Chip's 42 in Minnesota

[mrchipster]

Re: Chip's 42 in Minnesota

I was having a difficult time deciding how to tackle the last few chains and decided I would go all in...

The sharp V shapes were driving me crazy. So I decided that at chain 15 I would grind the bricks into a circular shape. That way bricks placed on top could be easily ground into an arc on both the top and the bottom.

This worked out extremely well as you can see from the photos.

The real beauty of this method is that I could use larger bricks. And not have as many lined up seams.

It wasn't that difficult with an abrasive grinding wheel on my 4 inch hand grinder to create the arcs. I was able to place the bricks side-by-side to get a nice continuous arc I think you'll agree.

Chip

[mrchipster]

Re: Chip's 42 in Minnesota

Here are the Jig photos I promised.

The jig is Built on a 2 x 8 piece of lumber. I cut a groove about 1 inch wide in the center of the board to allow clearance for the blade and also allowing the angled tables to swing up without hitting each other. Each table has two hinges placed along the groove.

On the inside corner nearest the saw, I drilled a hole for the angle bars that are attached to the top of each table. The bolt that goes through the hole is snugged up tight so that the arms do not move freely. Because they are tight they stay in position easily. You may want to add a clamp at the end of the the angle bar to more firmly hold it in position.

I screwed shims to the 2 x 8 to position the table in a horizontal. To make up for the thickness of the hinges.

I put pieces of brick underneath the table on each side to elevate the table into the angle I want.

The last photo shows how I make the table the same angle on both sides, I just measure up from the board equidistant from the saw blade in my case 9 inches away and if the left side is elevated 2 inches, then I just make the right side elevated 2 inches at the same 9 inch distance from the saw blade.

It took less than an hour to make this table and it has saved me a great deal of time.

BTW the hinges look strange because they are from a folding door and not real standard. They were just something I had lying around.

I hope this helps.

Chip

[mrchipster]

Re: Chip's 42 in Minnesota

Chip

I really like your build and your innovation. Do you have any pics of the jig for your saw? It sounds like what I am looking for as i begin to start cutting.

Gregg

I will post photos of the jig tomorrow as it is to late tonight to drag it out.

Chip

[garch]

Re: Chip's 42 in Minnesota

Chip

I really like your build and your innovation. Do you have any pics of the jig for your saw? It sounds like what I am looking for as i begin to start cutting.

Gregg

[mrchipster]

Re: Chip's 42 in Minnesota

Yes I used the fixed length IT to mark the brick insides to match the dome inside and the string was used to mark the angle of the sides I'd the brick. I marked the string where the outer dimension of the dome came to and was able to mark the back sloping angle quite easily.

I hope this makes sense.

Before laying the next brick up I would transfer the dimensions of the lower brick's top side to the bottom of the upper brick and that seemed to work quite well.

Thank you for your kind words.

Chip

[GianniFocaccia]

Re: Chip's 42 in Minnesota

especially the graduated inward angles the closer the arch bricks go towards the middle. Indispensible tool(s)?

Sorry Chip. I should have been more clear on my question. Did you happen to use your IT's to help configure the interior lines of your inner arch? I used a plywood template to figure out the lower angle and an IT to figure out the radius.

Your multiple magnetic IT's are nothing short of brilliant. They illustrate a refreshing willingness to innovate and progress convention.
John

[mrchipster]

Re: Chip's 42 in Minnesota

I just noticed the 'cap' you placed on the top of your arch form (metal/plastic?) on a prior pic. Damn, I wish I'd thought of that! And I had a spare 7' aluminum vertical blind just sitting there the whole time. Duh!

John

The cap on the inner arch form is a piece of thin sheet metal.

Chip

[mrchipster]

Re: Chip's 42 in Minnesota

Indispensable tool(s)?

John

Yes Indespensible tools - if you look back at some of my photos in this post you will see them. They have magnetic heads and at the center of the oven is a 1.125 inch diameter ball bearing that has been sliced in half and then welded to a piece of sheet metal.

This configuration allows me to have two brick tools going at the same time and also be able to completely remove the tools should I want to for cleaning or other reasons.

The other two are a simple stick with magnets on both ends. I use this as a marking and brick support tool. The last IT is a magnet on the end of a string for marking and angle checking.

All quickly and easily latch on to the center ball and are very simple to remove with a light pull.

I was concerned about keeping the ball clean but since it is polished chrome it cleans up with a rag or sponge in an instant.

At about chain 7 I decided to cut down the size of one of the brick setters and remove the clamp as the extra material was making it difficult to tap the bricks int place.

Chip

I am very happy with my design for the tool.

[GianniFocaccia]

Re: Chip's 42 in Minnesota

Chip,

Your oven's coming along nicely. Very impressed with the bond you're maintaining by staggering your bricks. Yes, it does get more tedious the higher up you go.

I just noticed the 'cap' you placed on the top of your arch form (metal/plastic?) on a prior pic. Damn, I wish I'd thought of that! And I had a spare 7' aluminum vertical blind just sitting there the whole time. Duh!

Keep up the great work. I really like the way the inside of your transition came out, especially the graduated inward angles the closer the arch bricks go towards the middle. Indispensible tool(s)?

John

[mrchipster]

Re: Chip's 42 in Minnesota

Excellent progress, just make sure you keep that inside nice and clean, trust me.. you do not want to get inside afterwards.. its a pain in the arse

The floor is a mess but it is covered in a sheet of 1/8 inch plastic and I do clean it up at least 2 times a day. I use an acid brush (no acid) to brush the inside of the dome at the end of each chain installation (or sooner if I am moving slow.

The brush removes a lot of excess mortar and makes cleanup much easier. Then I wipe down the inner surface with a sponge and rag to remove excess mortar.

The bricks I am using are used fireplace brick and they are getting slightly stained from the FB mortar but not serious. The drip marks you see in the photo are water that was on the brick from just wiping the last chain down.

I am planning on hitting the inside with a little diluted muratic acid tomorrow to clean things up a little better prior to closing the dome which may happen tomorrow or Thursday if the the weather does not hold.

That way I can have minimal cleanup issues for just the last 3 or so chains.

Chip

[mrchipster]

Re: Chip's 42 in Minnesota

While working today I found that it has become much harder to avoid lining up joints the higher up the dome progresses.

For that reason I have begun to cut a number of varying sizes of bricks to allow me to select from three distinct sizes as I fill the chain.

It is very hard to predict exactly how the joints will line up so being able to select a brick width at the time of placement saves the mortar from becoming set in the bowl.

On chains 12 - 14 I have been able to set 7 or 8 bricks and on chains 9 - 11 I was only able to set 5 or 6 at a time. To me this is significant because I am almost vertical at this time.

The bricks are holding quite well and I have only had 2 bricks slip out of place today. I guess I moved my IT to quickly.

BTW I had to cut the clamp off of my IT as at the higher angles it was just getting in the way I just have a very small L shaped piece of angle at the end at this time and it is working well.

Chip

[chidding]

Re: Chip's 42 in Minnesota

Excellent progress, just make sure you keep that inside nice and clean, trust me.. you do not want to get inside afterwards.. its a pain in the arse

[mrchipster]

Re: Chip's 42 in Minnesota

Well, I have made more progress after taking the weekend off to build a garage for my brother in law.

I know that sounds like work but it was quite fun and a distraction from the day to day.

After getting to chain 11, I think I am finally getting a handle on the FB Mortar and am finding it easier to set bricks and use less mortar. My brick cutting skills have been enhanced due to building a jig for the saw. I will post more on the jig in the future. It is based on another posted on the site and was quite easy to build.

I was able to put in 3 chains today and that included cutting the bricks. Yesterday I built the cutting jig and only got 1 chain installed.

I must mention one thing. I found at chain 11 that the angle of my bricks was becoming to elevated (vertical) and I had to take a drastic measure and grind the tops off of all of chain 11 to get the bricks back into alignment. I used a 7 inch diamond blade attached to an angle grinder. All came out well but I was not paying close enough attention to the top angle of the bricks and they became about 10 degrees to vertical and I needed to grind them back. It was easier to do this than to try and put in bricks that were wedged the wrong direction.

The bricks had been set on Friday and I did not grind them until yesterday. So they were fully set and the mortar was very firm.

I am on chain 15 with 2 bricks set, the top is about 15 inches in diameter from completion. I am out of round by about 3/4 inches but I think that is more of a characteristic of rectangular bricks causing V's and distorting the circle. I am not sure if the slight out of round is an issue.

The top is level within about 1/4 inch and I. am very pleased with that.

Photos are of my progress at about noon today.

Chip

[david s]

Re: Chip's 42 in Minnesota

The best one I've found is HEMP HAND PROTECTOR from the body shop. Most bricklayers don't use anything, I think the skin of your hands gets used to continual exposure to cement. I think lime is way worse, you really know about it if you have a cut or abrasion on your hands.

[brickie in oz]

Re: Chip's 42 in Minnesota

You should try it. Best kept secret for concrete work passed along from a friend of mine named Erik (Frenchie).

Chip

Id get beaten up at work.