Pyroceram placement

Status
Not open for further replies.
B

bwitty

Joined
Dec 5, 2003
Messages
103
I just got my 2 x 7 piece of pyroceram from Mr. Pryor and the platen is a wee bit longer...I would say prolly 1/4" on either end.. Would it be best to center the pyroceram in the middle of the platen or align it with either the leading or trailing edge of the platen. Wanting to place it for best performance.

Thanks in advance!
 
Unless you want to sent it back for another piece, I would just center it.
Don't forget to round the top, and bottom edges a bit too. That will help the belt over it without undue friction, or sharp edges to catch on the belt.
You can do that on the belt grinder.
Start with something like 120, and finish with 220, or higher. The ceramic will glow orange when you grind it, that's normal.

Also, make sure that your platen(the steel one)is flat before you epoxy it on, if it has seen a bit of use. Put it on the disk sander to flatten, or however you do it.;)
 
Byron, my platen hangs over a bit on both ends, too. Not a big thing, as long as it doesn't put too much strain on your belts if the platen can't be adjusted in a bit.

One thing you should definitely do, though, is radius both ends of the platen to avoid straining the buttsplice. Start with a 60 grit belt and create the radius. The glass will glow an eerie orange, but don't let that spook you. Finish off with perhaps a 120-220 belt and yer ready to glue it on. Some use epoxy, some JB Weld epoxy, some silicone tub glue. I personally used Zap-a-Gap.

Be aware that this stuff builds up static when it's dry like in winter. Don't be freaked by the spark, but do, if possible, ground yourself or the platen so it won't nail ya. There was a recent thread about this...

Good luck.

Edited to add: dang, Mike, ya beat me too it. :D Sounds like we read the same manual.... :)
 
so ya dont think it being a bit short will any difference? or would it be better to go ahead and send it back?
 
No, Byron, I don't think it will hurt. However, Steve's a good guy, and I'm sure he'll take it back if unscathed if you're not comfortable with it. The worst that might happen is it may round the edges of your platen a bit, which IMHO, is no loss.
 
The steel platens on my two Burr Kings are rounded at least 1/4-3/8" on each end, just from the belt going over it. That was before I put a pyroceram platen on it.

It won't hurt anything, Byron.
 
Well Mr. Pryor, Trusting person that he is, is sending me one about 1/2" longer tomorrow via priority mail! Im gona send him the old one back as well, but I thought that was mighty nice of him to send it before he got the old one back first!

Can't wait to get it so I can finish the grinds on my first knife. right now its all kinds of messed up and uneven. Hopefully this will allow me a more uniform grind.

Thanks for the responses guys! I always get the kind of help I need from yall here.:D
 
Just be aware that this pyroceram is not perfect. Yes, it is slicker and your belts stay cooler. Your grinding will improve, due to the flatness of the platen. But, this stuff will crack and break. I had a platen crack on me, without any direct impact. I can only guess it was from leaning into the grind, but who knows? Having said this, I still use the stuff, and will keep on using it.
 
You make a good point, Danbo. A student chipped out my first piece by laying the platen on the floor and that was all it took. I think, though it has great strength specs in some respects, it is definitely not that strong at the edges. Point source impacts especially will hurt it. The point you make about it spontaneously breaking brings something to mind to tell Byron:

When you are gluing the platen on, I think it critical that you get as even a coat of adhesive on as possible, especially in the area where the workrest will sit. This stuff doesn't flex well, and I think an airgap behind the ceramic, pressure like from profiling a blade, and you have a recipe for a crack. When you glue it, if at all possible, smoosh it around a bit to even and flatten the adhesive.
 
Originally posted by fitzo
When you are gluing the platen on, I think it critical that you get as even a coat of adhesive on as possible, especially in the area where the workrest will sit.
Click to expand...

This is exactly how I replaced mine, Mike. The only thing I did differently was to use PC-7, which for those unfamiliar, is a beefier version of JB Weld. I made sure all the adhesive was nice and uniform on the platen before I applied the Pyroceram and flattened it out real good, pressing out any air pockets. Then I sealed any gaps around the edges with whatever squeezed out.

That seemed to make a huge difference over last time, even to the point there's not as much static.
 
Jeff, could you tell me any more about this PC7? Is it made by the same manufacturer as JB Weld? Also, is it possible this stuff is conductive, while JB weld isn't? I haven't had the static problem until recently, as the house dried out in winter. Now I understand what everyone's talking about;

"Make it go away, Mommy!!!!" :D
 
They appear to be two different companies, Mike. JB Weld is made by The JB Weld Company, and PC-7 is made by PC-Products. They both have websites also if you do a Google search and use their names.

FWIW, the PC-7 seems to be thicker and grainer than the JB Weld. As far as being more conductive, I doubt it.
 
Mike, here's a site. Don't try searching for PC-Products on a pc. I can't think of a worse name for a company to have, in this day of PC's.
You'll get a million hits.

http://www.right-tool.com/pcprodepandw.html

;)


Edited to add;They have wood hardener, and wood rot terminator also. may be something the home stabilizers would be interested in?!?!:confused:
 
Thanks, Mike! I just bought something like this called "Rock Krete" from lee valley, but I don't think it's metal-filled.
I'll poke around this site.. lots of stuff...
 
Speaking of metal-filled...

Some donkey-kong here at work dropped an allen wrench into his press and it scraped a nasty gouge around the impression cylinder - right where the numbering head is supposed to land. Normally, on a different machine I would take out the cylinder, have it welded up and then rotary ground down to the correct size again. Not so on this machine. The cylinder is huge, like 300 lbs. To top it off, it would take me all of one day to take it out, send it to Connecticuit to be ground, and would run about a week I bet to do it all. This is not a good thing to happen to a machine that produces somewhere in the neighborhood of $1200 per hour revenue for the company.

So I had to come up with a better way.

I used some of the Devcon Titanium putty from McMaster-Carr. I cleaned out the grooved cyliinder, smeared in the putty on a Saturday, and sanded it down by hand early that Monday morning. That was almost 2 years ago, and the press has been running every day since, with no problems. That's pretty good stats imo due to the fact that that numbering head has been crashing down on that repaired area enough to go through up to 5 parts of paper to make an impression for all this time.

Good stuff!
 
Amazing what some of these polymers will do nowadays, isn't it?
 
For attaching the glass. Someone here told me to try pressure sensitive tape. The plain ol' 3M stuff. 3 strips of that held for longer than I used the glass.

Even gave it some cush. Worked fine even after I cracked the glass.

I scraped the tape off went back to the steel platen and haven't bought any new glass yet. Someday I'll replace it.

Steve
 
Has anyone tried using Turcite as a platen liner? It's pretty tough stuff. Its used on the ways for a lot of machinery. I've personally never seen it wear out on anything.
 
Originally posted by jhiggins
Has anyone tried using Turcite as a platen liner? It's pretty tough stuff. Its used on the ways for a lot of machinery. I've personally never seen it wear out on anything.
Click to expand...


Jeff,
I'm not familiar with Turcite. What is it?:confused:
 
Mike Hull said:
Mike, here's a site. Don't try searching for PC-Products on a pc. I can't think of a worse name for a company to have, in this day of PC's.
You'll get a million hits.

http://www.right-tool.com/pcprodepandw.html

;)


Edited to add;They have wood hardener, and wood rot terminator also. may be something the home stabilizers would be interested in?!?!:confused:
Click to expand...
I just built a vacuum chamber for stabilizing wood handle scales. Picked up some scraps from a local plastics manufacturer/distributor - 3"x15" clear cylinder & two 1/2" nylon discs - and also grabbed a brake bleeding hand pump from good 'ol Hazard Fraught for ~ $40 altogether. I saw that PC Rot Terminator 50% off at local Fleet Farm.

I couldn't find anything online about using it as a vacuum stabilizing resin, so I'm testing it myself.

I ran 3 vacuum cycles over a two hour period, holding at 25 in. Hg. No indication thus far that it hasn't worked, but I can't machine or sand the sample wood piece (small mahogany block, no rot or burl/figure of any kind) until it's fully cured, which is supposed to be ~1 week.
 
Status
Not open for further replies.
Back
Top