Small-cell foam?
Small-cell foam?
(OP)
I've got a novelty product I need to source, which is to be made of a light-weight (low-density?) but tiny-pored foam that would be good for applying screen-print or pad-printing. I'm thinking of a material similar to some of the step-aerobic blocks I've seen before (or preferably even more light-weight than that stuff, with less structural strength), but am unsure of what material that is.
Any ideas, directions to check out?
Thanks!
Any ideas, directions to check out?
Thanks!
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.






RE: Small-cell foam?
When you mention the screen/pad printing, do you mean that you must be able to print on the material or with the material?
Would any of the lower density grades of REN board work?
RE: Small-cell foam?
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Small-cell foam?
Thanks for the quick input already. Any other ideas? The foam can be quite "squishy", too, but if we print directly onto it, we'll need quite small pores. Lighter weight is better.
Perhaps the priority order is:
1. Cheap
2. Printable (using whatever means)
3. Soft, not rigid
4. Light-weight
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.
RE: Small-cell foam?
This may be what you want for a google search:
closed cell polyethylene foam self skinned
Seems a lot in your neck o' the woods...
Cheers
Harry
www.tynevalleyplastics.co.uk
RE: Small-cell foam?
RE: Small-cell foam?
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Small-cell foam?
PE is ok to print these days - etching inks/surface treatments etc. If colour not important, laser marking may be an option.
It's also cheap - a criterion stated. PU is more expensive. Some foams are skinned with something else but adds cost.
Cheers
Harry
www.tynevalleyplastics.co.uk
RE: Small-cell foam?
Many grades of PE actually contain a little vinyl acetate to improve stress crack resistance or toughness.
If you are talking directly to a manufacturer rather than a distributor of the foam, they may be able to guide you as to availability of a relativly high VA content grade.
Regards
Pat
See FAQ731-376: Eng-Tips.com Forum Policies for tips on use of eng-tips by professional engineers &
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RE: Small-cell foam?
RE: Small-cell foam?
And I've finally remembered where I'd seen what I'm imagining in retail before and found examples of the type of foam I've been imagining. If you Google (images) "pilates blocks" you'll see some beveled foam blocks of the small-pore type. One leads here and even demonstrates direct printing:
ht
Think this is a form of PU or such?
I appreciate all the input on this. Perhaps in the near future I can better disclose what this is all about. Meanwhile, I'm getting pulled back onto yesterday's project for the day and probably into tomorrow until completion. So don't worry (ahem, btrueblood), I'm taking this quite seriously and am very grateful for all the input I'm receiving here. Not sure who else would be able to help in this way, so I truly value your input.
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.
RE: Small-cell foam?
Thanks!
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.
RE: Small-cell foam?
FWIW the blocks you showed I don't think are a urethane rubber, more likely are cut from larger pieces of EVA, see link below
http://www
Theo, do you _not_ want a skin on the surface? Don't know if that can happen without cutting the part from a larger piece, don't all foams tend to form a skin when molded, due to contact/wetting against the mold wall?
Interesting subject here, and want to hear from the expert guys: if you want a lighter foam, doesn't that usually mean coarser bubbles (larger cells) in order to reduce the amount of material? And is this not related to the material chosen, in that a given material will tend to form a certain cell wall thickness?
RE: Small-cell foam?
RE: Small-cell foam?
If EVA is simple enough to mold, and the mold would provide a skin around the foam, I think that would be ideal. After paying for tooling, the per-unit cost of a molded form ought to be less expensive than one cut on all sides, right? Further, I'd think a skin around the foam might allow more course bubbles within while providing a good surface to receive print, right?
Thanks, all!
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.
RE: Small-cell foam?
In that case, these things could be extruded and cut to lengths (skin around four sides, not on cut ends if cubic in form) and printed on up to four of the skinned sides. I'd like to have stronger opacity than the pool noodles, but that should be a matter of density control, right?
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.
RE: Small-cell foam?
Dunno about opacity, but it will probably be a function of fillers, and cell size/density. Probably matters what color you pick too (any color, as long as it's black :).
Sorry, not much usable info from me (thus my comment about not feeling like I earned that star) -- and this is pretty much a filler post while we wait for Pat and the rest of the experts to log in again.
RE: Small-cell foam?
The E in EVA is ethylene. It is not normally called EVA until you exceed about 5% VA.
When the VA content gets to around 50% (I think from memory) it can be melted by rubbing between your hands.
Regards
Pat
See FAQ731-376: Eng-Tips.com Forum Policies for tips on use of eng-tips by professional engineers &
http://eng-tips.com/market.cfm
for site rules
RE: Small-cell foam?
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.
RE: Small-cell foam?
RE: Small-cell foam?
Regards
Pat
See FAQ731-376: Eng-Tips.com Forum Policies for tips on use of eng-tips by professional engineers &
http://eng-tips.com/market.cfm
for site rules
RE: Small-cell foam?
RE: Small-cell foam?
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Small-cell foam?
you may want to talk to someone who does RIM process
they could at the very least advise you on materials if not supply your parts.
RE: Small-cell foam?
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.
RE: Small-cell foam?
You can also make a microcellular foam by adding CO2 during injection molding using patented processes such as mucell (http://www.trexel.com/) or a similar process patented by the IKV in Germany.
When foaming it's a very good idea to add 1 weight % of fine (2 micron) calcium carbonate as that gives the foam cells somewhere to nucleate and start growing to give a more even, finer foam. Good grades to try would be Carbital 110 from Imerys or Omyacarb 2AV from Omya.
Chris DeArmitt
www.phantomplastics.com
Consulting to the plastics industry
RE: Small-cell foam?
As always, a wealth of knowledge.
Regards
Pat
See FAQ731-376: Eng-Tips.com Forum Policies for tips on use of eng-tips by professional engineers &
http://eng-tips.com/market.cfm
for site rules
RE: Small-cell foam?
Chris DeArmitt
www.phantomplastics.com
Consulting to the plastics industry
RE: Small-cell foam?
And--congratulations!
Jeff Mowry
www.industrialdesignhaus.com
A people governed by fear cannot value freedom.