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Advice On Purchasing An Extruder

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I have never used an extruder, but I've read about them and admired images of things made from them. I really dislike making coils -- I don't have the touch (or perhaps the patience) to make uniform ones.  So I'm thinking of buying an extruder for that purpose to start with, and eventually to actually make useful shapes - square tubes for small boxes or large tubes for the beginnings of human forms.  Any suggestions as to extruder size, manufacturer, material, and a basic set of dies?

 

thanks, Jayne

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if you are making many coils you may want to get the larger one.  if only a few at a time there is a handheld version which you can use with various size metal washers that have different size holes in them.  if you go for the big one, the round tube on the scott creek is very easy to clean, much easier than the square ones.  the clay gets stuck in the corners of the square ones and it is hard to get out.

 

i was interested in making square tubular pieces and found that controlling the clay as it comes out is very difficult.  it wants to curve instead of coming out straight.  the books about extruding offer advice on this problem.

 

having a plastic box with plaster in the bottom to keep coils in is very helpfu.

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I like the brents as the cap connection is the easiest to go on and off--I also like the scott creek model-the steel one as aluminum is just to soft.

The bailey is supposed to be very good as well.

All the smaller hobby models are just a waste of good money for me.I have a friend with one that says- ends in Star and it holds so little clay its ridiculous-one squirt and it empty.

They all will do coils well.

spend some $ and get a good one.

Mark

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I chose the Scott Creek large4" square one.  I have their hand held for smaller amounts . Why that one ?  I wanted the largest box without going to an expansion box, although it is offered for this model .  I do not find it at all hard to clean.  Larger, you fill it fewer times before you get the job done , holds 22 lbs.,and it makes large hollow extrusions.  If you have curling problems with them, as I did initially, it is about not having the center die spaced evenly in the housing, I block it in with clay lugs that are pushed out with the first 2" of extrusion.  I load it with fresh pugged clay made softer than it comes out of the bag.  Well prepped clay is imp.  I block it and load as evenly as possible.

They make sets of shapes dies and a set of 3 larger ones .  If your clay is soft enough, important, the dies for the smaller gun can be used in the larger, but can't do the reverse.  Another reason for choosing the 4" square box, I can get a diagonal strip that is almost51/2 wide with it. I use that feature a lot when hand building.

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For a little more on this check the strand in the FAQ on extruders.

 

I had Bailey's in my HS classroom and loved them. I had one that was really heavily used when we did extruder projects in class. Held up very well. Clevis drive was awkward in the beginning, but once you get used to it, quite easy.

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Thanks for all your answers.  I don't know if it's just me, but I have a hard time finding anything by typing a subject into the search box here.  I typed in "extruder" and got nothing.  After posting and reading your answers, I followed Pres' advice and tried again, and all it pulled up was my question and your answers.  So, Pres, how do I "check the strand in the FAQ on extruders"?  And what is a Clevis drive?

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I purchased a 4" Northstar stainless steel, square and have been very happy with that choice. What I like most are the dies . . . they are 1/4" plastic that are beveled so that the clay compresses as it passes through the die. My dislike is t he bridge for hollow forms . . . it leaves a trace on the outside of the extruded form that has to be ribbed. I used a Brent in a community studio and did not like the metal dies and found the clean up to be a pain.

 

I've bought a set of the Michael Sherrill extruder dies; the zipper bridge is just fantastic. And, his dies are finished to a point of leaving no exterior marks. Great craftsmanship, but they cost a bit (okay, a lot) more.

 

I've also ordered extruder dies from machinists who make them "on the side" and have been unhappy with the quality. The die bridges tend to be clunky and the dies have too many sharp edges.

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The michael sherrill dies are very nice

If you want hollow forms pay lots of attention the bridge form that floats the hollow inner form

My brent dies are all aluminum and I made all the handle forms from solid rounds but they are not hollow.

I did made my own oversizes round dies from aluminum as well to shoot out larger tubes.

If lots of hollow forms are neede an expansion box works best as it hold more clay-bailey has great expansion boxes.

I rarely ever clean my extruders (onlt knock off the dry stuff) as I shoot many pugs a week thru them for all my handles. They really get a work out here.

I do not do much hollow work anymore but if I did the sherrill bridge is the best for that.

The extruder book may do you well at this point-not sure as I do not own it.

Mark

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I have the large square Scott Creek model and getting the hollow dies in place can take some getting used to. I use dowels to even the space between the two parts and carefully check while I push down the clay. After that the clay keeps the dies in place.

 

 

For making coils and handles they are very easy to use. Working with hollow dies and cleaning/prepping a large extruder is time consuming.

 

I agree for coils and handles a hand held extruder can be a good alternative.

 

One thing I'd suggest is to try one before you buy. See if it matches your creative flow...

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someone would work hard to show me that an expansion box works.  i used the big bailey at st pete clay. the expansion box is about 8 inches and the clay above it is in the center of a 4 or 5 inch tube.  tell me HOW that clay gets into the far corners of my die.  never worked, got just the shape in the middle where the clay above pressed down.  what makes it spread out?????

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someone would work hard to show me that an expansion box works.  i used the big bailey at st pete clay. the expansion box is about 8 inches and the clay above it is in the center of a 4 or 5 inch tube.  tell me HOW that clay gets into the far corners of my die.  never worked, got just the shape in the middle where the clay above pressed down.  what makes it spread out?????

My guess is the clay was to hard-soft clay works best in the larger boxes.

The only one I have seen is the large power Bailey extruder-seemed fine with soft clay.

Mark

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I used the expansion box on the one at the HS for years. Dies were Bailey's also. As you said Mark, if the clay is stiffer, it will not fill the box properly. Also if the die has a lot of openings near the center it does not work well. The center on the hollow dies acts as an expansion barrier, as the clay hits it it expands out to fill the edges then goes through the die. Design of a good die is really a large part of working with large hollow dies. I did find the C-clamps a little cumbersome to put on, and again if the clay is not soft enough the die gets broken up from the pressure.

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I really liked the Scott Creek extruder I had in my first classroom.  I've also used a Brent, which does have a collar, that is super easy, to take on and off.  The Scott Creek collar, isn't too bad.  It has three pins, that hold it on.  It usually wasn't an issue, though as the students didn't always clean it the best, sometimes, the corresponding holes in the extruder tube, were hard to see.  Anything is better than the two wingnuts, that some extruders use to hold the dyes.  It takes waaay too long to swap out the extruders, that use those.

The big reason, that I liked the Scott Creek, was the notched ladder, that the plunger uses.  I prefer that, over then Brent yolk set up.

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I have the Scott Creek Aluminum version. I work exclusively with little loafers which is a white clay and aluminum leaves no marks on your clay.

 

I make LOADS of small boxes, square, round, triangle, as well as mugs. I use my hollow dies all the time and finally had the money to purchase the handle die and it has made my handles look so much better, totally worth the price. I made myself a die for coils from a blank one and it speeds up coil forms immensely and it's so nice to have the exact size coils for every row. If you make your own coil die roll out coils to the size you like then measure the diameter and drill the holes in your die to this size. It's also better to drill several holes rather than just one small hole in the center as it takes a ton of pressure to squeeze the clay through the one small hole but several holes works fabulous and you will never outbuild your coil supply.

 

I found that assembling the hollow plate is easier done outside the extruder. Assemble it upside down on your work table. I measure the openings on all sides to make sure they are as equal as possible. I then place a piece of painters tape over the openings in a couple places to hold it in place while I put it in the extruder. I add the clay, pull down a bit just until I see the clay pushing around the tape then pull off the tape. If you have trouble with the extrusion wanting to curve, hold the beginning of the extrusion to sort of guide it straight down once it has a few inches on it the weight will make it hang straight down. I have 2" dowels and 2x2 lengths of wood that I feed the extrusion over before I cut it off with a wire. It keeps the forms nice an neat and much easier to handle and I can pull a 3 foot extrusion easily this way.

 

I did find that to get smoother extrusions I had to file the edges a bit on the hollow dies. I kept having an issue with a ragged surface in places until I realized the die was the problem. After I filed the edges just a tad I have had no problems with ragged surfaces on my extrusions.

 

I've been eyeing the expansion box and hollow die set... Really like that hexagon shape.... Hmmm Dear Santa I've been a good girl and all I want for Christmas.....

 

I also have the tiny...TINY extruder that's like a fat pen with little washer dies. I use this for hair and small vines on small projects, it's very quick and easy but it doesn't extrude much which is why it's really only good for small detail addons.

 

I LOVE my extruder and think it was a great buy and is a huge asset to my studio.

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Yeah Pugaboo, I have a couple of those mini-extruders for my classroom.  They are indeed handy, but you want the clay to be REALLY soft.  There are some dyes that are pinhole size.  I've never used them, and to my knowledge, neither have my students, but that would take quite a bit of force and borderline slip, to get the clay to go through that.

 

Those little extruders are all over eBay.  The mid-sized, handheld extruders are OK, at best.  I've got two, in my classroom.  The plastic plunger head cracked fast on both.  I'm looking for something to replace it.  I've been tempted to talk to the industrial tech teacher, to see if he can either cast me one, or use their 3-D printer to carve me up one.

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(The big reason, that I liked the Scott Creek, was the notched ladder, that the plunger uses.  I prefer that, over then Brent yolk set up.)


I have both of these extruders-the clevis pin on the brent takes getting used to and now Brent makes a  notched ladder as well-I would go that route today if I bought one.I think after using the ladder for 35 years I tend to favor them. I am a bit different as well  as I use the heck out of this tool almost daily and the Brents are so heavy duty they have been issue free.Now that Brent makes a ladder its a no brainer. I would also consider using another brands hollow forms as you can trade them around-al long as its a round 4 inch or sqaure model-meaning sq is sq and round is round.


My Scott creek has had about every modification you can think as it was an orginal model from the orginal inventor(1970s). The cap was before the pin model of today and its now a Brent cap after redoing it. The ladder wore out and the handle was beefed up. I have gone thru 2 plungers discs and the barrel is now 1/8 larger than it once was.The brent has survived with zero issues.Most will not push that much work thru one so it really comes down to way works for you.


Just make sure it holds at least 10#s of clay


Stainless is great but I never and I mean never have seen rust on my porcelain  from my rusty extruders and thats all we use in them-(Porcelain). The barrels are rusting-but contamination is of ZERO issue.


Mark

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Wow, what a ton of information.  Thank you all.  I'm starting to think I should buy an extruder book first and the extruder second.  I do have an option to borrow an extruder from a former potter, so maybe that's the way to go before I buy so I can figure out what I really need versus what I want -- which as usual, is everything! 

Jayne

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I don't know how I've missed the forum FAQ and Help Topics all this time, but thanks Mark and Pres for directing me to it.  A wealth of information about sooooo many things awaits me!!!!

jayne

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Benzine - yep the clay has to be super soft. I usually spritz a small ball of clay and wedge it in then store it in a baggy shaped into cigar shapes and only pull out what I need as I need it. I haven't used all those tiny plates in the pen sized extruder just the round ones in the biggest size and then down a couple. Mine is actually all metal but still feels flimsy to me so I am careful to only use really soft Clay in it. It's really only good for small add ons if I need anything more than a single vine or hair for one angel I load the Scott creek and use that.

 

Terry

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i forgot that that tiny thing is called an extruder.

 

 my suggestion was to use the one that looks like a tool used for caulking around windows and stuff.  the washers i use for coils are 2 inches in diameter and various size holes in the center. 

 

jayne, borrow that extruder and put it to work.  if you really like it, maybe you could buy it from the owner.

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Terry, from some stories I heard from a Middle School classroom, those mini-extruders are pretty solid.  Some students were taking them, loading them with clay, and then slamming them, plunger first, into the table top, to cause the clay to shoot upwards....

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