Cheap Supplier of UHMW/HDPE??

[Bugsysiegals]

I'm finally about to assemble some long overdue drawer boxes for some shop cabinets I cut up more than a year ago! 

I could use Domino's but figured the drawer lock bit I have would like nice with Baltic Birch; however, it has terrible tear-out when cutting the sides standing up.  I setup a 3/4" MDF zero clearance board but the tiny piece near the bottom of the bit keeps breaking off so I tried 3/4" Maple veneer plywood and same issue. 

Would UHMW make for a stronger zero clearance fence and is anybody using this for this purpose or is it far to expensive other than making router bit height setup gauges?  If it's a good idea, where can I find a good cheap source of it?

 

[Sparktrician]

You can try Woodcraft.  YMMV... 

 

[rst]

You can usually find UHMW on Ebay at better pricing than Woodcraft

 

[RightAngleDesign]

I'd go for recycled HDPE from US Plastics. It's very affordable.

 

[Cheese]

I'd contact a couple of local fabricators and ask them if they sell their "drop" or who they sell their scrap to.

If you need sheets of the stuff then the local fabricator may also be willing to sell you some sheets.

The upper midwest has tons of plastic fabricators.

 

[Bob D.]

McMaster-Carr is also an option for small quantities of UHMW, HDPE, fiberglass and many other materials.
Might not be the cheapest but they will usually have what you need in stock and ship that day or the next.

I have bought fiberglass WF beams, angle, channel, and sheets from them for various projects I worked on.
They also have UHMW and HDPE sheets and shapes.
https://www.mcmaster.com/uhmwhttps://www.mcmaster.com/hdpehttps://www.mcmaster.com/fiberglass

 

[Michael Kellough]

McMaster is a great source with an awesome website and app,
except neither provide information on shipping.
Bulky stuff will accrue a large shipping charge.

I ordered a 2x3 foot sheet of 1/16” plastic and the shipping charge
was twice the value of the material.
Small boxes and envelopes have reasonable shipping charges.

 

[Bob D.]

It is true that you can't see shipping charges up front. Something I have fed back to McMaster a few times when I used to order from them almost daily.

 

[GigaWatt]

I'd go for recycled HDPE from US Plastics. It's very affordable.

I ordered one 3/4" x 12" x 12" and one 3/4" x 12" x 24" sheet of Recycled HDPE from US Plastics.

When the order arrived the 12" x 12" sheet was correct however the 12" x 24" sheet measured 11-7/16"x 24". Since I need the correct size for what I had designed I contact them by email.

They replied that they had a +/- 10% tolerance on the sheets. They also admitted this info was not listed on the web page. They did offer a refund on that piece or replace with the correct size if they have it in stock. If you order from them, you might want to keep this in mind when designing projects.

 

[08G8V8]

I'd go for recycled HDPE from US Plastics. It's very affordable.

I ordered one 3/4" x 12" x 12" and one 3/4" x 12" x 24" sheet of Recycled HDPE from US Plastics.

When the order arrived the 12" x 12" sheet was correct however the 12" x 24" sheet measured 12" x 11-7/16". Since I need the correct size for what I had designed I contact them by email.

They replied that they had a +/- 10% tolerance on the sheets. They also admitted this info was not listed on the web page. They did offer a refund on that piece or replace with the correct size if they have it in stock. If you order from them, you might want to keep this in mind when designing projects.

And they are claiming 11-7/16” is within 10% of 24?

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[GigaWatt]

I'd go for recycled HDPE from US Plastics. It's very affordable.

I ordered one 3/4" x 12" x 12" and one 3/4" x 12" x 24" sheet of Recycled HDPE from US Plastics.

When the order arrived the 12" x 12" sheet was correct however the 12" x 24" sheet measured 12" x 11-7/16". Since I need the correct size for what I had designed I contact them by email.

They replied that they had a +/- 10% tolerance on the sheets. They also admitted this info was not listed on the web page. They did offer a refund on that piece or replace with the correct size if they have it in stock. If you order from them, you might want to keep this in mind when designing projects.

And they are claiming 11-7/16” is within 10% of 24?

Sent from my iPad using Tapatalk

I'm sorry, I missed typed in the post. It should be 11-7/16" x 24". I corrected the post.

 

[08G8V8]

I'd go for recycled HDPE from US Plastics. It's very affordable.

I ordered one 3/4" x 12" x 12" and one 3/4" x 12" x 24" sheet of Recycled HDPE from US Plastics.

When the order arrived the 12" x 12" sheet was correct however the 12" x 24" sheet measured 12" x 11-7/16". Since I need the correct size for what I had designed I contact them by email.

They replied that they had a +/- 10% tolerance on the sheets. They also admitted this info was not listed on the web page. They did offer a refund on that piece or replace with the correct size if they have it in stock. If you order from them, you might want to keep this in mind when designing projects.

And they are claiming 11-7/16” is within 10% of 24?

Sent from my iPad using Tapatalk

I'm sorry, I missed typed in the post. It should be 11-7/16" x 24". I corrected the post.

Ok, that makes sense.  10% still seems like a very generous tolerance.

Sent from my iPad using Tapatalk

 

[WastedP]

A few months back a guy wanted some HDPE blocks cut, but he wanted to provide the material.  But he wanted me to tell him where to get it.  I told him to try the restaurant supply houses for cutting boards made from 100% recycled material (these should be cheap and solid HDPE).  He bought some off Amazon and delivered them to me.  I don't know what he paid, but the material looked clean and worked as expected.

I use a phenolic zero-clearance insert, much harder and more durable than polyethylene.  I think it was about $22 online.

 

[Cheese]

Ok, that makes sense.  10% still seems like a very generous tolerance.

The +/- 10% tolerance on plastics is pretty common within the industrial community. It all starts with the coefficient of lineal expansion on plastics. I’m not saying their correct...just saying that’s the story they prefer to extoll.

 

[Bugsysiegals]

I'd go for recycled HDPE from US Plastics. It's very affordable.

I’d no idea about these guys, thanks!!  But wow do they have a lot to choose from ... HDPE, Phenolic, UHMW ... is HDPE the better choice for this application?

 

[GigaWatt]

The following info was taken from the iPoly website. Considering the following info, a piece of hdpe that should be 12" x 24" being of by 9/16" doesn't make sense to me. The piece in question was dead on 24" in length however 9/16" short in width. The 12" x 12" piece was correct in size. I think the 12 x 24 piece was a miss cut or the end of a sheet that came up short.

How much does HDPE sheet expand and contract?

Indoor applications experience little to no expansion as the temperature is constant. For outdoor ambient temperature applications, the rule of thumb is that a 4 x 8 sheet will expand as much as 1/2" in length from a hot summer day to sub-zero winter temperatures in cold climates. HDPE sheet expands more in length than in width, due to its molecular structure.

The easiest formula to use for an exact expansion / contraction dimension is as follows:
Degrees Fahrenheit:
0.00011 x degree variance(°F) x length in inches
Example: 0.00011 x 30°F temperature change x 96" long sheet = 0.3168" or approximately 5/16"

Degrees Celsius:
0.00019 x degree variance(°C) x length in inches
Example: 0.0001 x 16.7°F temperature change x 96" long sheet = 0.3173" or approximately 5/16".

While these numbers may seem high, expansion can be easily negated by using correct installation techniques.

 

[tjbnwi]

Online Metals. As mentioned above, make sure you check the final sizes of the order. I've had thenm come out smaller than what I spec'd.
https://www.onlinemetals.com/en/buy/plastic-sheet-plate-uhmw-natural-virgin

Tom

 

[Cheese]

The piece in question was dead on 24" in length however 9/16" short in width. The 12" x 12" piece was correct in size. I think the 12 x 24 piece was a miss cut or the end of a sheet that came up short.

I agree, the narrow piece was probably a cutting error on their part. Once cut, the stuff remains relatively stable for most applications. It's only in those engineering applications when you really start picking the nits that the coefficient of thermal expansion can get in your way, or if you're combining this with a different material, for instance stainless, then there can be some issues.

The +/-10% tolerance is usually on material thickness, not overall piece-part size. I think the person you talked with was just confused.

 

[08G8V8]

The piece in question was dead on 24" in length however 9/16" short in width. The 12" x 12" piece was correct in size. I think the 12 x 24 piece was a miss cut or the end of a sheet that came up short.

I agree, the narrow piece was probably a cutting error on their part. Once cut, the stuff remains relatively stable for most applications. It's only in those engineering applications when you really start picking the nits that the coefficient of thermal expansion can get in your way, or if you're combining this with a different material, for instance stainless, then there can be some issues.

The +/-10% tolerance is usually on material thickness, not overall piece-part size. I think the person you talked with was just confused.

I agree, 10% on thickness is reasonable. 10% on profile is not.

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[Michael Kellough]

The piece in question was dead on 24" in length however 9/16" short in width. The 12" x 12" piece was correct in size. I think the 12 x 24 piece was a miss cut or the end of a sheet that came up short.

I agree, the narrow piece was probably a cutting error on their part. Once cut, the stuff remains relatively stable for most applications. It's only in those engineering applications when you really start picking the nits that the coefficient of thermal expansion can get in your way, or if you're combining this with a different material, for instance stainless, then there can be some issues.

The +/-10% tolerance is usually on material thickness, not overall piece-part size. I think the person you talked with was just confused.

I hope not. I’d be pissed if I ordered 1” thick material and it was off 1/10th inch.

If I know the cutting tolerance is too low I can order a larger piece and cut it myself but I can’t easily add to a slippery material like PE.

But it looks like you’re right. At McMaster the thickness tolerance of 1 UHMW-PE is +/- .07”. At 3” it’s +/- .15”

For comparison the thickness tolerance for Delrin is 3 times tighter.