[Marc4444]

(Not sure if I placed this thread in the right forum. God. So many of them ...)

I have been building very detailed ( using 1mm router ) models from MDF, but the pain of sealing and painting it afterwards was too much (apart from the fact that with priming, sanding, priming, sanding, painting sanding, ... half of the details are gone).

Anyhow. I was looking to build my next models in HDU. Never worked with it, though. So I was looking for a local supplier (Markham, Ontario) and stumbled across a "100% cellular PVC" board at Home Depot. It routes ok, sands nicely. Except I sometimes collect burrs around the router and then my precision is gone. Anyone have any thoughts ? ("Go to HDU immediately" or such)

By the way: If someone has tiny HDU scraps kicking around, I'd really like to try them ( 0.5" x 3" x 1.5" is enough, will pay for shipping of course). But I'll post that in the "Wanted" forum ...

Thanks, guys !

[Mike 1948]

(Not sure if I placed this thread in the right forum. God. So many of them ...)

I have been building very detailed ( using 1mm router ) models from MDF, but the pain of sealing and painting it afterwards was too much (apart from the fact that with priming, sanding, priming, sanding, painting sanding, ... half of the details are gone).

Anyhow. I was looking to build my next models in HDU. Never worked with it, though. So I was looking for a local supplier (Markham, Ontario) and stumbled across a "100% cellular PVC" board at Home Depot. It routes ok, sands nicely. Except I sometimes collect burrs around the router and then my precision is gone. Anyone have any thoughts ? ("Go to HDU immediately" or such)

By the way: If someone has tiny HDU scraps kicking around, I'd really like to try them ( 0.5" x 3" x 1.5" is enough, will pay for shipping of course). But I'll post that in the "Wanted" forum ...

Thanks, guys !

Try these guys, they will send you a sample pack of HDU's and other various substrates. http://www.midwestsign.com/index.asp


Mike

[High Seas]

Those are really SMALL pieces you are looking for -- Try Freeman Supply - see if they have some RENBOARD/tooling board in a sample pack -- they did a few years back and were just 'bout that size - "xactly!
BTW welcome to the CNCZone! Lots of friendly helpful folks.
Cheers - Jim
PS can't say if they'll post to Canada?

[DragonXtreme]

Freeman has the sample pack for $25. I use the 10lb and 20lb HDU day in and out here. Its great stuff and I do have a fair collection of drops that I keep. Its a shame your in Canada but if you do find it meets your needs, get with me and maybe there is something we could work out with shipping and such.

[todd71]

(Not sure if I placed this thread in the right forum. God. So many of them ...)

I have been building very detailed ( using 1mm router ) models from MDF, but the pain of sealing and painting it afterwards was too much (apart from the fact that with priming, sanding, priming, sanding, painting sanding, ... half of the details are gone).

Anyhow. I was looking to build my next models in HDU. Never worked with it, though. So I was looking for a local supplier (Markham, Ontario) and stumbled across a "100% cellular PVC" board at Home Depot. It routes OK, sands nicely. Except I sometimes collect burrs around the router and then my precision is gone. Anyone have any thoughts ? ("Go to HDU immediately" or such)

By the way: If someone has tiny HDU scraps kicking around, I'd really like to try them ( 0.5" x 3" x 1.5" is enough, will pay for shipping of course). But I'll post that in the "Wanted" forum ...

Thanks, guys !

I doubt HDU would be any better than MDF if your looking to have a "smooth" surface finish. You'll still have to seal the open cells of the material after cutting. Which can be a pain. Maintaining details could be even worse than with MDF. I could send to you some 15lb desity HDU to test out. Or you can contact http://www.precisionboard.com/ for some samples. I've had better luck machining Rayite100 http://chembar.com/wp-content/upload...ite100_tds.pdf for small detailed carvings.

Good luck,
Todd
www.innovative-accents.com

[judleroy]

Why not just go to a local plastic supplier and get some scrap pcs. of PVC or HDPE. While your there get some acrylic and Delrin or acetal. You will find Delrin can cut amazingly smooth parts if you Use the right tools.

[DragonXtreme]

I doubt HDU would be any better than MDF if your looking to have a "smooth" surface finish. You'll still have to seal the open cells of the material after cutting. Which can be a pain. Maintaining details could be even worse than with MDF. I could send to you some 15lb desity HDU to test out. Or you can contact http://www.precisionboard.com/ for some samples. I've had better luck machining Rayite100 http://chembar.com/wp-content/upload...ite100_tds.pdf for small detailed carvings.

Good luck,
Todd
www.innovative-accents.com

USG is no longer making Rayite per there regional reps I talked to last year. My experience with 20lb HDU holds a very sharp line, far better than what I have seen MDF do and there are no open cells to fill no fuzz to remove.

Just my opinion on the HDU

[todd71]

"and there are no open cells to fill no fuzz to remove." Of course there are "open cells" when you cut HDU. It's closed cell structure opens when
cut. This may not matter much on signs and architectural features. But if you want a "SMOOTH" finish for your high detail carving. May not be much better as far as time and effort go. It really depends on Marc4444 expectations and requirements. Haven't had to buy Rayite in awhile. Still got 40lbs in storage. To bad if they did discontinue. Great stuff. Good for casting. Add some crushed bronze, polish up, looks awesome. May have to go with Hydro cast next time around.

Todd

[DragonXtreme]

Sorry todd71, the higher you go in density the finer the detail you can acheive as well as the smaller the size of the cell structure and to correct, you are right on cutting the cell but per his original post it was concerning MDF and what he has to go through to finish it, I just commented what my experience was in 20lb verses MDF, I personally use HDU up to 38lb as well as Renshape 460 for model and mold work. I rarley do signs and most of my architectural work has to be as close to plaster smooth of a finish as I can get which for the most part I can easily get to with 20lb and higher HDU and the finishing techiniques I use here. Blast board, Sign Board (15lb and under) really is junk for the majority of what I do here even if their base chemical structure is the same.

I really wanted to get some Rayite 100 but every source I tried at USG last year said it was discontinued and unfortunately I have not found a source for Hydro Cast that could supply the quantity and a decent cost value I would need for the models and molds that I do. I could burn through that 40lb bag you have just in one mold/model. If you know of a source the sells in the pallette range the info would be appreciated.

If you took offense to my statement due to the quote, it was not meant to be offensive, just tried to give my experience even though you were talking about 15lb and I was talking about 20lb.

[todd71]

HA! No offence taken. Just pointing out HDU's closed cell structure will have open cells when cut. I never said don't try it. Just saying he may have to prep the surface for paint. And that's not always easy to do with HDU. Depends on what Marc4444's looking for. Considering the model size is 0.5" x 3" x 1.5" and is cut with .039 end mill. I figure he's got alot of detail in a confined area. Where as with the machinable plaster or even plastics, as judleroy suggested. Maybe better suited to go right to paint. There again, I don't know the job requirement. I would recommend trying it all. That's the agony of figuring it out. That's the joy of success. That's the journey.:cheers:

[Marc4444]

Thanks, Guys. I ordered some high density HDU and I am curious how it'll turn out. In the meantime I actually got this "100% cellulose PVC" under control and it works quite nicely for me. I visited a plastic supplier and got a sample of pretty much exactly the same stuff. The brand name escapes me right now but it appears to be a brand product. I'll compare it with HDU once I get a chance.

[ger21]

Any one use this "3D" MDF?
http://www.sierrapine.com/index.php?pid=70

[todd71]

Any one use this "3D" MDF?
http://www.sierrapine.com/index.php?pid=70

I use this stuff. Not much different than "Micro-refined MDF II ".
Which is way better than the Home depot stuff for finishing.
The main thing about "Medex" is it's formaldehyde free bonding agent.
Which is pretty much required by building codes and designers.

So how'd this all work out?