View Full Version : Clamping surface-finished work pieces without marring?

09-30-2010, 05:05 PM
What are some methods for clamping parts with finished surfaces without marring the finish?

09-30-2010, 05:14 PM
Put something softer than the work in the jaws. Brass, Aluminum, plastics, etc.

Al Messer
09-30-2010, 05:16 PM
Put something softer than the work in the jaws. Brass, Aluminum, plastics, etc.

I have been known to use Leather on occasion to pad the jaws of the lathe chuck, or Lead to pad the vise jaws.

09-30-2010, 05:27 PM
A lot of times a piece of masking tape is sufficient.

09-30-2010, 05:57 PM
My vote goes for masking tape too.


Dr Stan
09-30-2010, 06:13 PM
Put something softer than the work in the jaws. Brass, Aluminum, plastics, etc.

These plus lead, copper and even plywood on occasion. Plywood is very good to use under large flat parts when clamping on top of the milling machine or drill press table. That way you can cut into the plywood and not mar the machine. Plywood also tends to be reasonably consistent in thickness. If you need to be more accurate hardboard (Masonite) or Plexiglas can be used, but of course are more expensive than plywood.

09-30-2010, 08:16 PM
I usually use pieces of aluminum. Sometimes stuff as thick as 1/16", mostly flashing, which is .015". There's a box of miscellaneous pieces next to my mill, used on it, and both lathes. I've even used a strip from a soda can, but that's only .005".

Davo J
09-30-2010, 08:59 PM
I use printer paper, it helps to give it extra grip as well. I also use it if something hasn't got a great surface, so I don't mark the table surface.


Your Old Dog
09-30-2010, 09:18 PM
I got no idea where or what it was used for but I bought a roll of lead about 1" wide and wound up to about 5" in diameter. It was a yard sale find for something like a buck or two.

A neighbor gave me a cigarbox full of shimstock with some very thin copper sheet thrown in for measure. The thin copper also works well.

09-30-2010, 09:34 PM
I have a few pieces of copper on hand as well as a supply of old business cards for this purpose. These work in the lathe chuck as well as the milling machine vise.

09-30-2010, 10:56 PM
Drywall tape works quite well in the mill or drill press vise. In the lathe, brass shim stock is what I prefer to use.


Mike Burdick
09-30-2010, 11:00 PM
I like to use tempered masonite.

10-01-2010, 02:35 AM
I like to use tempered masonite.

I tried to anneal the stuff before I cut it but it kept catching fire!

10-01-2010, 04:48 AM
Alternatively, make 'soft jaws' for your vise/lathe/drill press, Or use collets. (While collets can marr, the wide distrabution of force generaly prevents it)

10-01-2010, 06:31 AM
If the "good face" is a reference face - against the vise fixed jaw or the mill table etc. it may be hard to put anything between the "good" and reference surface/s. Just good machine hygiene is all that can be used - depending on the accuracy required.

Otherwise I use newsprint pages between flat surface or brass or aluminium between clamps and the surface to be protected.

Not being so/too "heavy-handed" with spanners on clamping bolts and vise handles will be a good start too.

Good table or vise stops drastically reduces the need for clamping forces to reduce "sliding"movements.

10-01-2010, 02:42 PM
I have also used thick paperboard, like found in cereal boxes. The important thing is that the material is not rubbery or elastic. For example, I think electrical tape or vinyl would be a bad idea since it lets the part shift slightly.

10-01-2010, 03:15 PM
My vote goes for masking tape too.


Make that another vote for masking tape. I use double layers on 45 slides and have yet to mar a slide.

10-01-2010, 04:00 PM
handily having 4 different logos on business cards means Ive got a large supply of them :)


10-01-2010, 08:20 PM
A strip cut from an aluminum beverage can, works well in the lathe. In the mill, card-stock, scrap brass or aluminum between clamp and workpiece.

10-02-2010, 04:00 AM
I have some brass and copper shim stock (stainless and steel too) bought in a cheap bulk lot at auction. But most of the time, I use cut up aluminum cans (save the good stuff for when it matters). I've also used the "cereal box" (card stock) cardboard. For the lathe I also have both aluminum and nylon(?) soft jaws for the 3 jaw, and I have brass jaws that came on a Wilton Machinists vise. And I've got temporary (either magnetic or slip on) jaws with rubber, aluminum (including v-block), or leather surfaces. I've even used a discarded leather belt at times.

One word of advice, both copper and brass can require periodic annealing or they get hard enough to mark steel.

10-02-2010, 10:24 AM
Brown paper bag paper works quite well.

I tried using masking tape in a lathe chuck years ago. The tape's glue got slippery as snot under pressure,and the part I was machining started slipping badly. I was only able to save it by stomping on the brake bar instantly. Plus,the lathe was turning slowly at the time.

Dry paper,on the other hand,is great for adding skid resistance to your smooth chuck jaws. It holds like crazy,and is non marring.

the kid
10-02-2010, 12:40 PM
good ideas in here, I will often put wood on my vice jaws but I like the leather idea, I will get a couple scraps from the local leather shop and glue up some of that sheet magnet stuff to the back and make a set, I have used paper in the lathe as I have no soft jaws, and I think I will make some aluminum jaws for my DP vice. I need to get my shop put back together first, everything is currently in storage:(

Your Old Dog
10-02-2010, 12:56 PM
And now from down under we have "machine hygiene" thrown into the mix. If that's the case my machines would look like a street urchin was using them :D