Giffin Grip Tips?

[algebraist]

Hi All -- I just bought a Giffin Grip.  I should have expected that a new tool would require some practice and skills to be effective...  I tried it out a few days ago and was not all that successful.  Basically, I am trimming mugs (essentially cups, since the handles don't get attached until after trimming), and found that if I clamp the GG down enough to hold them still, it damages the mug (and if not, the mug slips and gets damaged as well).  The obvious solution, I guess, is that I am going to have to let the ware get significantly harder before trimming; as with everything else, timing is key.  I don't love that solution -- for one thing, I'd prefer my handles to have some flex before I attach them, and ideally they'd be at the same stage of drying as the mugs.  (For another, trimming gets harder if the ware is dried too long.)  Another thought I had was perhaps to put thin slabs of clay on the GG's gripping pads, to make them stickier; this might help, but I'd have to be careful to make them all the same thickness, and they'd need frequent changing, and in the end it might cancel out the convenience of using the GG.  A thin pad in the center of the GG to sit the mugs on, so they stick more to the base, might also help.  Anyway, the upshot is that while I was sitting here brainstorming, it occurred to me that lots of you love your GG's, and probably have this all figured out...  Hence this post, asking for advice.

I mostly used the "arms" to hold my mugs in place, choosing lengths that gripped the mugs about 2/3 of the way up.  (I tried just making the sliders grip the mugs at the bottom -- i.e. the rims -- that was worse.)  Also, I have recently become enamored of throwing mugs with distinct, dramatic, throwing lines (i.e. a relatively deep, sharp-edged groove that spirals up the cup); that might be especially challenging for the GG to preserve undamaged...

Thanks in advance for any and all tips!

[oldlady]

love my grip but i do not make mugs.   you might practice with something else, a glass from the kitchen might be ok to start with.   not a good one!   but try to use the sliders.  just practice holding the glass in the sliders at differing speeds first of all.   when you are comfortable with that, apply a little pressure to the part which would be trimmed off.  once you feel that balancing just right, try a mug.  maybe just throw a couple of practice mugs for this step.

you will learn to love your grip.

[Pres]

I use the GG on nearly everything, from mugs to bowls, to small jars and larger pieces. I have also used the GG to hold chucks for trimming made from plumbing pieces for plastic pipe. I hope I have a little expertise to pass on. I have been using one for over 30 years.

When using the GG with mugs and small jars, I set the gripping pads to just below the base of the upside down piece. This allows me to trim when the pot is between cheese hard and leather hard. I don't like to trim anything before cheese hard. Definition of cheese hard is to imagine a slice of clay. . .if held out by the hand parallel to the floor, it will slump slightly from gravity. However the leather hard piece done the same will not. Both will be able to be bent slightly without cracking, the cheese hard more so. Both will trim well, but the leather hard piece is stronger and more resistant to denting. So trim at cheese to leather hard stages, then join your handles. 

If interested in some of the chucks I use to trim lids, chalice stems, and other things, check out my blog site. 

 

best,

Pres

[JohnnyK]

It does sound like the clay is too soft to effectively hold in place without distortion, particularly since you are gripping at 2/3 up. If you are just basically trimming the bottom of the mug, you might consider installing the handles if they don't rise above the rim of the cup. As you said, the timing is critical...use Pres's suggestions above...

JohnnyK

[GEP]

I hardly ever use the arms. Only when trimming something with a neck/mouth that is narrow compared to the body, therefore prone to tipping over when upside down, such as a bottle. I use the sliders for just about everything, I recommend letting the mug body get more dry. It’s fine to attach a wetter handle to a drier mug, as long as you use good attaching techniques. Then cover the mug with plastic for a day or two (depending on your climate) to allow the moisture to equalize. 

[CactusPots]

I trim like a madman.  Every pot that will fit on the GG gets the treatment.  Lots of scrap.   I use a piece of (rubber?) shelf liner under to eliminate any wobble from the rim of the pot when holding the pot high with the arms.  I also use little pieces of that material to hold an irregular pot on the center I want.  Spacing the arm pads independently.  As an example, if the rim and the thrown foot don't have the same center, I can get the foot centered and trim the pot.  Not good throwing technique, I know, but it really doesn't affect the final product.

[algebraist]

Thanks for all the great advice.  Lots to try; I will keep at it!

[kristinanoel]

I had the same problem - I the sliders, not the arms, and I've started using cotton pads in between the mug and the slider to protect the ware. Works great, and size/thickness is uniform so I don't have to worry about things getting out of alignment. 

 

[Mark C.]

your work is to wet-let it dry a bit-with ceramics moisture content is key-that takes a lot of trail and error learning-handles go on when they are just right-trimming same deal.

Learn by doing-no short cuts-I have used the grip for eons and its takes getting used to. I rarely use the arms,especially on small stuff. I throw no trimmer mugs so I cannot add to that but any handled pot should be trimmed before the handle goes on.

[Selchie]

I use foam and wrap it around the piece, held in place with elastic bands, then hold it in place with the GG. I use the foam in place of a chuck for upside down vases and non-uniform shapes. It takes a bit of time to set it up, but it stops denting and I can trim at the stage of hardness that I like to use.  

[Babs]

Only uses sliders for shallow dishes. Arms and pads  away from rims where possible. A great tool but first I learned tapping moving pot and sticking it with blobs of clay.

Have a series of thrown chucks smand plant pots for narrow necked or undulating rimmed vessels.

[algebraist]

9 hours ago, Selchie said:

I use foam and wrap it around the piece, held in place with elastic bands, then hold it in place with the GG. I use the foam in place of a chuck for upside down vases and non-uniform shapes. It takes a bit of time to set it up, but it stops denting and I can trim at the stage of hardness that I like to use.  

A great idea; thanks.

[Benzine]

Beyond all the great advice given, I will add one thing.  I use a Giffen Grip, in my classroom, and I always tell the students, to *not* let the sliders/ arms do all the work.  They have a tendency to just casually set their ware on there, and then torque on it, in an attempt to center the piece, no matter how far from the center it was.  

This will distort or damage, even something that is leatherhard.  So I tell them, to use the sliders as more of a guide, and still scooch the ware, bit by bit, as they move the sliders.  

[Mark C.]

One other point is mantaince of that grip

they get slow to slide when clay gets under and in-between the two platters.

I take mine apart and blow it off and spray a bit of spray silicone on the bottom part resemble and its works super slick for a tad.

[algebraist]

Benzine -- thanks.  I was doing just as you say -- using my hands to get the pot in the center, with the GG as a guide, and only clamping it down when the pot was completely centered.  My distortion happened during the trimming.  But great advice.

And Mark C., thank you, too -- I imagined it would get glopped up eventually; good to hear someone explain the maintenance clearly.

Heading out of town on Thursday for a couple of weeks, so I won't have a chance to experiment/practice further for a while, and I'm going to try to avoid touching a computer while I'm away as a matter of good vacation policy...  So I will check back in around August 7th or so.  Thanks everyone.

[algebraist]

I'll add this tip, since I just learned it the hard way: Make sure the GG is not propped up on one of the bat pins.  This morning, mine was.  Every pot was apparently off center, and I destroyed 4 of them before I figured it out.  (Finally I started to suspect that the GG was not centering them properly, and I loaded it up with a glass jar.  When that, too, was way off, I was just about ready to take advantage of their 90 day money back guarantee...)  Lesson learned!

[Benzine]

Yep, it is tough to tell sometimes.  That's why, when I put it on the wheel, I'll get the wheel going and set my finger on the Giffen Grip, to make sure there isn't that wobble.  

[oldlady]

there are two simple things you can do with your GIFFIN GRIP that will help all the time. 

the first is to line up the grip on the wheelhead making sure not to hit a bat pin.  then take a sharpie or other marker and draw two vertical lines  on the metal wheelhead using the sides of each of the 3 black holders on the rim of your wheelhead as a guide to mark exactly where to put the grip next time.

the second is to hold a sharpie, maybe a new one so the lines are crisp, vertically above the grip and spin it.  put concentric lines about a half inch or so, no need for perfection, apart all the way across the surface of the grip.   you have to hold the sharpie tightly because it will want to fly out of you hand at the grooves.   if you then use your sharpie to follow the groove all the way across the grip surface so it lines up .........   this is too hard to describe so nobody can possibly misunderstand such a simple concept so i am posting a photo.

if you mess it up somehow, you can remove all the sharpie marks with hairspray  WHICH CONTAINS ACETONE for those who will feel compelled to correct me. 

[Benzine]

No need to use hairspray, OldLady.  Hand sanitizer works perfectly, for removing Sharpie!

[Babs]

Thanks guys. The perfumes in hairspray drives me outdoors...could be doing the spraying outdoors:-!

[cathydombrovske]

I'd echo those who say to let your cups dry a bit more before trimming. If the handles are quite a bit wetter than the cup body, loosely cover with plastic for a day or two to let the moisture equalize. I do this and hardly ever have cracking between the cup and handle. And I'm going to try the cotton pads myself, to avoid getting marks from the arms on my cups.