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ncjeeper
07-02-2015, 02:27 PM
I have a small 12x18x3 plate in the shop and would like to protect it. I checked E-bay, Enco, and Grizzly but I cant seem to find anyone that sells them. Anybody have a source? I guess worst case I could try and have someone sew one for me.

gzig5
07-02-2015, 03:01 PM
On one of mine I use a large, thick sheet of cardboard with a band taped on around the edge to keep it from sliding off. The other has a fairly thick piece of felt with the corners sewn to provide a nice fit. Either one can be made with a razor knife and some tape. If you are worried about slamming something onto it have Home depot cut you a piece of 1/8" hardboard to fit it. Glue some scrap strips on the corner to keep it centered.

rock_breaker
07-02-2015, 03:10 PM
If you are speaking of a precision ground caparison plate I made a wooden frame just larger than my plate and put a 1/2 inch plywood top on it. The plate is in the middle of my shop so a lot of different things are placed in what ever space is available Hope fully the 1/2 inch plywood will avoid damage from any sharp objects that may fall on it.

Good luck with finding a cover and have a good day.

Ray

SteveF
07-02-2015, 03:35 PM
A one inch thick piece of XPS foam board that I had laying around and cut to size is what covers mine.

Steve

DICKEYBIRD
07-02-2015, 03:41 PM
Here's what I did with mine. It's still working great! Somehow the pics got juggled up but you'll get the gist. That's back when I learned all about airy points. (Gotta love that kinda stuff!)

http://bbs.homeshopmachinist.net/threads/36253-Surface-plate-cart?highlight=AIRY+POINTS

Video Man
07-02-2015, 04:24 PM
I made a stand out of angle iron and a cover out of oak plank and oak-veneer ply. When the plate is not in use it makes a sturdy shelf to put other stuff on, and the height of the cover insures nothing is going to bang into it http://i1053.photobucket.com/albums/s474/hsmuploader/splate1.jpg (http://s1053.photobucket.com/user/hsmuploader/media/splate1.jpg.html)

boslab
07-02-2015, 07:47 PM
I don't know how relavent or usefull this is, in the lab we had a place called the balance room, analytical balances were on granite surface plates, the ones not in use were under cover of the usual felt and ply lid, what was interesting is that the plates were sat on lead sheet, even the iron ones, it apparently damped vibration in the case of sensitive balances, and helped to keep the temperature of the plate steady, there was an optical bench in one lab that sat on lead too, something I didn't quite get but there we go!, the lids were all wood with felt backing, a new plate was delivered that was different, it had a lid made of UHMW plastic stuff, black with a lip all round of a grey plastic, it was about 10 mm thick, 3/8" to all those what like imperial, it was quite heavy stuff but very good, you would be able to drop a cannon ball on it without touching the plate, just some thoughts
Regards
Mark
(Still trying to figure out what the hell to do with a 2' lapping plate, it was to bloody heavy to get nicked!)

sarge41
07-02-2015, 09:01 PM
Here's what I did with mine. It's still working great! Somehow the pics got juggled up but you'll get the gist. That's back when I learned all about airy points. (Gotta love that kinda stuff!)

http://bbs.homeshopmachinist.net/threads/36253-Surface-plate-cart?highlight=AIRY+POINTS

DICKEYBIRD: Very nice stand for your plate, but doesn't the buffing wheel throw crap all over your boxes of stuff below? Anyway, very nice job, wish I could be that neat.
Sarge

Paul Alciatore
07-02-2015, 10:01 PM
I only have a 9x12 plate and when it is not in use I just throw an old towel over it. I try not to put anything on top of that. Emphasis on "try". This does keep it clean, but I wipe it with the towel before each use.

JoeLee
07-02-2015, 10:16 PM
Do you think that wiping them clean too often can cause wear??? Even if you keep it covered you would still have to wipe it off prior to use.

JL............

Forrest Addy
07-03-2015, 03:07 AM
My 24 x 36 Do-All granite surface plate spent 40 years under a piece of rubber belt that overlapped by 1/2" all around. It kept the plate safe from even heavy knocks and dumb accidents. Also the faying surface was easy to keep clean. Wood, felt, etc captures dirt and either uses it to scratch the plate or leave sprinklings behind requiring a cleaning every time you need it. Rubber, however, is imporous and smooth.

Flat surfaces attract stuff in need for a place to be. In my next life my surface plate cover will be shaped like an A-frame roof so anything I set on it will slide off to the floor. Then when I need to get at the plate I don't have to find places for accumulated stuff.

Cleaning? "Granite" (as used here covers a wide variety of stone materials) is a mixture of minerals some subject to attack by even mild chemicals. Once in a while a granite plate may be cut from quarried stone containing calcium or other vulnerable constituents. Harsh cleaning products may attack them. Go boldly forth to clean you precision flat anyway you choose but be aware every hard surface has it vulnerability.

I use lighter fluid or lacquer thinner to remove grease and oil and non-ammoniated glass cleaner to clean it. Nothing harsher.

Peter.
07-03-2015, 03:27 AM
Hi Forrest,

That must explain why I once went to look at a fairly large granite plate to find it had pock-marks all over the surface where it looked like one particular type of aggregate had been dissolved away by some means.

Charles Spencer
07-03-2015, 09:26 AM
I only have a 9x12 plate and when it is not in use I just throw an old towel over it. I try not to put anything on top of that. Emphasis on "try". This does keep it clean, but I wipe it with the towel before each use.

I do the same except the towel is doubled up and there are two layers of cardboard under it. It is on my bench work area and I keep my tablet and keyboard on it. That stops it from being an available flat surface.

Rosco-P
07-03-2015, 09:53 AM
covers, etc. http://www.standridgegranite.com/cases-covers-and-cleaner

justanengineer
07-03-2015, 10:08 AM
I keep mine in a pretty wood box with removeable lid.

As for cleaning, both Starrett and Do-All recommend cleaning before every use. Considering I only use my home plate every few months I dont need to clean it often. At home I use glass cleaner, at work we've got Do-All's aerosol spray cleaner and another spray protectant that get used daily.

ncjeeper
07-03-2015, 01:39 PM
covers, etc. http://www.standridgegranite.com/cases-covers-and-cleaner
Thanks.

Baz
07-03-2015, 06:49 PM
Oak is acidic and corrodes iron. Rubber releases acid as it decoposes. Plastic encourages sweating in humid environments owing to the thermal mass of the plate. Cloth and felt absorb water so release it too.
Generally I suggest a half inch of softwood or ply as a protection is advisble in a wokshop environment with an intervening layer of rust inhibiting paper for an iron plate and plain paper for stone plates perhaps with addiional layers of paper cloth or foam to buffer against grit and swarf particles.

oldtiffie
07-04-2015, 12:59 AM
I have both a 24" square and a 12"x 16" surface plate/s.

Both are just under card-board sheet cover.

I only clean them before and after use.

Both are on benches and so need no floor space at all.

The 24" plate is sitting on three machinist jacks so I can re-level it in no time at all - but only if it needs it.

The smaller plate is usually just carried to my mill table and seated on several strips of painters masking tape - I will level it if needed.

Surface plates by their nature are very robust and strong and will take a lot of abuses - a few (or more) chips and gouges here and there should not be a problem.

Most times I use the mill table "as is" and clean it up when needed - otherwise I use a section of "float" glass (seated on painters masking tape).

There is no need to level a surface plate unless a truly horizontal reference plane is required. If a level surface is not needed but a flat (not level) plane is adequately provided by a surface plate or perhaps a bit of "float" glass or even a mill table or the table on a surface grinder - or anything else that is flat enough for the job in hand.

Its just a matter of knowing how flat or level a reference surface has to be - and not necessarily what you want (as opposed to what you think you "must have").

Same applies to the accuracy or "grade" of a surface plate as a Class 4 (i.e. Class D) which is usually known as "Shop" grade and is normally way more accurate than is really needed in most shops.

If I dropped and/or chipped or gouged my plates I would not worry about it at all as there are several reliable shop "spot "checks that can be used to check the plate/s well enough for "shop" use.

Check out the accuracy and grades of surface plates at "Shars" -it might be an "eye-opener".

http://www.shars.com/

http://www.shars.com/products/measuring/surface-plates

mars-red
07-04-2015, 08:21 AM
My iron plate came with a nice wooden cover, and I made one for my small granite plate by cutting a section out of an old air mattress we were throwing away. I used superglue to join the edges, it ended up being a nice fit over the top of the plate.

Edwin Dirnbeck
07-04-2015, 10:36 AM
Why cover it? Unless you are TRULY Working in "tenths" of thousanths on an inch,You will never wear out a good granite plate in your lifetime.Shop space is allways at a premium.Every shop that I have worked in ,use the plates exposed, except maybe in the inspection room. The place that I retired from had about 10 plates scatered around and once a year an outside vender would come in and inspect and rework them if needed.Most of them were ok as is.Edwin dirnbeck