Return to the Clay and Ceramics Forum | Post a Follow-Up

Slip casting smoker/ grill

Posted by Daveweldz (My Page) on
Thu, Nov 8, 12 at 0:27

Hello all
Please forgive me I am a metal guy. Also please forgive my spelling and grammer as I cant seem to go back and fix any thing I type.
I was asked to develop a wood pellet fired grill for a customer. My knee jerk is a sheet metal enclosure but I have come to the conclusion that a cerrmic type grill is the way to go. Some of you might be familar with the "egg" type BBQ's on the market. I have been looking at a solid slip cast type product from a two part mold, think of two halves about the size of a gas BBQ grill. This would not be a mold were you pour out the slip once a certian wall thickness is achived, I am assuming slip can be used to to make a solid peice. Again please humor me as I am not informed. I understand the slip molding process, There seems to be limit to the practical size of slip molding, I see were sinks and toilets are slip molded. Is the limit based on getting the green peice out of the mold and keeping it stable before firing?
Another question is slip type. The temp inside this grill would max out at maybe 900F on the high side. Seems like earthware type slips might be the right choice, do you want to keep the operating temp well below the firing temp / cone number? Should I be looking at a refractory type material?
Be nice to make this semi light both from a shipping stand point and insulating stand point. Looked into paper slip mix but wondered if the green piece can be glazed during intial firing as the paper out gasing may bubble the glaze. Any thing else you can add to the slip to promote weight saving and insulation while still allowing a one step fire/glaze process? This stuff looks realy fun but i need to be realistic.
My shop is too full of other hobbies for me to think about doing this myself, I am hoping to learn enough to approuch those who may be equiped and inclned to tackle such a project.
Thank you

Follow-Up Postings:

RE: Slip casting smoker/ grill

I see you asked this a couple years ago, but I'll answer what I can anyway.

the size of any ceramic piece is limited by the size of the kiln to fire it. If you can fit only one piece at a time in the kiln, that increases production time and cost. The folk who make bathroom fixtures probably have HUGE kilns.

I'm confused about what you're planning; you say,
"This would not be a mold were you pour out the slip ... I am assuming slip can be used to to make a solid peice"
I don't see why you would want a solid barbecue. And a slip-molded piece more than 1/2" thick is likely to crack like crazy when drying--and forget about firing it, it would probably explode.

I don't think glazing greenware (even without paper) is a good idea; if the glaze vitrifies before all the moisture is gone, you'll get cracking or worse.

If you don't need a glassy finish, you could use underglaze or colored slip to coat your greenware.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Clay and Ceramics Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here