PU with MDI

Anyone has tried any good foam made with MDI? I am after more information about how good that technology is these days.

Checked out this website the other day… seems interesting… www.homeblown.co.uk



ive just done two boards with homeblown foam, very nice to work with and shape and excellent customer service! i even emailed them my own dimensions on one of the boards for them to machine up.

And what about… hardness, weight, flex pattern and yellowing? Is it a good product for high performance short boards? The Homeblown blanks or any other MDI based PU foam.

i probably cant give you an objective answer to that as i have never shaped any other foam, and never shaped a high performance shortboard. try general discussion area for better answer i think.

Thank you!!


The ones I have seen were very heavy. Maybe the weight factor has been adjusted. The bio foam I think is made by them also it’s very brown compared to standard and EPS.

I’ve done a board with a PU/MDI blank. I was signing on to start a new topic with a questions about this when I saw your topic. the board I did has been glassed for a couple months now and I’ve ridden it a couple times but I’ve noticed something really odd. there are pressure dings all over the board. if you look at the bottom it looks like someone put their knuckles in it all over. I was wondering if this is something that happened because of the blank or something I did wrong somewhere else in the process, i should mention that it was the first board I shaped and glassed myself. anyone else had a problem like this with PU.MDI blanks

I’ve tried the HomeBlown BioFoam blanks recently… Found them incredibly easy to shape and very consistent…the foam is soft and should be glassed with epoxy resin for the neccessary strength and weight. I’ve found that the finished product holds a great flex, very much comparable to traditional P/U. I only finished these about a month ago, but they have held up very nicely… although I have noticed some “soft” spots, Im not sure what has caused these… any answers??

I just recently started shaping U.S. made Homeblown Foam here in CA.

Here’s my take after shaping 25K…er, 2.5 boards (since the IRS is asking questions) of other types of blanks (Clark, Extruded,EPS…)

Homeblown’s foam is finer celled. They state 1000x finer cell than Clark under a microscope. It is noticeably different after cutting the outline. I am not a computer ridge shaper…I hand shape everything, so the outline is cut with an 8 or 10 pt. saw. The stuff cuts like extruded foam like the 80’s. I usually prefer to rough about 8 or 10 bds. for a day than come back next day and finish them all…this bumps the average to say 5 lb’s (or whatever) per day.

The MDI has a tendency to tear if you mow too fast using planer blades (I have 2 Clark fitted F20A Hitachi planers (the big model) and plan on setting up w/spiral abrasive drum. If you slow down on your passes and angle some, it cuts beautifully. But I want (and need) to move faster (so I don’t fall asleep) and that’s why I’m hoping the abasive drum will let me zoom along at a decent pace. The foam is harder than Clark, hence the tearing. Some tearing can be alleviated by running the planer backwards…same thing I found successful w/extruded foam back in the dark ages. I am sure the tearing could be reduced or close to eliminated if HB wanted to make a blank more like Clark had done…but that is not the point.

When sanding out the board start with 40 or 50 grit. Again, this stage feels like the ‘sawing’ action of extruded foam. You can then shift to 80 then 100 or 120 or finish with 100 screen. Start w/hard block and move to soft/padded blocks per your preference…play with it to see what works best for you. I also mentioned to Ned @ HB that the foam seems well suited to using a disc (power sanding w/a pad).

Whoever was talking about dents all over the board has me puzzled. The cell structure of this foam should resist denting better than Clark’s or comparable foam densities. I had heard quite the opposite: reports of far less denting, 15% better compression strength as shown in tests. The Homeblown tuck delivered blanks to me 2 days ago and they had a stack of test blanks going to Cal Poly (San Luis Obispo) for further testing by one of the college’s departments up there.

I deal with Eric and Ned (McMahon) @ HB. Ned has shaped over 30K boards himself and if you have questions I am sure he can give you much insight. He mentioned to me that the finished blanks initially feel heavier when finished shaped then after glassing, the boards turn out lighter due to less resin absorbed. Makes sense, really. He also mentioned that you may choose to change from 6 oz. glass schedules to using some (or all) 4 oz. due to the increased strength of the blanks.

Update 9/03/07.I noticed some denting on my shaped blanks after glassing even though I tok good care in handling. I also noticed a rather strange pattern on the gloss coat before polishing…something I’ve never seen before. However, I did glass w/Warp glass, and the pattern on the marks disappeared after sanding out and polishing. As far as the previous compression claims and changing to a lighter glassing schedule…just be aware that if you start with a heavier core, you end up with a heavier end result. The consideration about less resin absorption attributing to a lighter finished product is valid, but only to a point. If you are concerned about your poly’s absorbing a lot of resin while glassing, shoot a seal coat of UV lam on them or catalyzed seal coat as nee be. Epoxy of course is a different story but you are dealing with a dramatically lighter core to begin with.

I will also make another point while I am on here. In my first couple groups of blanks, I was getting the “ply” stringers. I just ordered a three stringer for an order in NJ and Eric told me they were not going to be offering these stringers anymore. When I asked why they said shapers want to use what they are used to.

Ply stringers can be great or a real pain in the ass depending on how the gains are arranged and the quality of the glueup. I had the blanks blow from the stringers after lamming and this is a real detiment to a finished board. You can open up the bubble and styrene to pull sme resin down into it but even then that’s not a guarantee that the void dsappears. Furthermore, we shouldn’t have to deal with crap like this. The new materials are not fully worked out, and having to deal with more than the usual host of problems is time consuming and not cost effective.

We used to order our Clarks with two 1/8" vertical grain spruces reversed lammed side by side. This was stronger than a single 1/4" stringer! Three laminated together were even stronger. So HB had these 5 ply lams all dne up and what they were calling 1/4" was closer to 3/8"…but people would rather use what they know and let the strong stuff get used in Hawaii:WHERE THEY KNOW BETTER. I guess people think ply is cheap…ever hear of marine plywood? I’d suggest running an ASTM on he same thickness of a glue lam vs. a piece of basswood and see what happens…

The glue lam position still holds true but havng stringers blow air after laying up is a bummer.

anyway i dont think that big surfboard producers will use this Bio-foam. Producers are not still mentalized with the problem and for example the white colour of the foams is really difficult to reach using natural components and MDI. Imagine Bio-foam has the same or better properties as TDI foams the price will be higher and as i mentioned producers dont interest that. sad but true.

Well, actually Al is getting about 100 HB’s per week…the Homeblown site people read is a bit misleading about the color…being that you can get the blanks in white or in straw (natural). The white blanks I’ve shaped are as white as anybody’s. The comment about sending the “material” to Hawaii was about the lammed stringers only, not the foam.

Updated Sept 07…the caim that Al was r is getting 100 banks is hear say. Maybe he is and maybe he isn’t…nobody really knows, and since this was written I hear claims that CI is using so and so’s blanks all the time…take it for what it is worth: hear say.

As far as questioning it’s potential for popularity…Bush has helped that along with Iraq and gas prices. There was a fair bit of petroleum in Clark’s blanks; after all, the blanks were plastic and a lot of the material was resin based and most of us know resin is a petroleum product as with other plastics. However, now you can get leashcups made from corn, and the midwest is gearing up to produce 49% more corn this year due to subsidized ethanol programs. Of course this will mean nothing if Ford, GM and Chrysler don’t up the production of flex capable vehicles. Their record isn’t very good when people were screaming “no more gas guzzlers”. If you’re on a budget get a Smart Car or ride a bike to the beach.

Open your mind, your ass will follow!

OK, i am just talking about the situation in europe (im from Spain) and i would like to see another situation but the truth is that producers dont care the materials used to produce the blenks. I understand that HB nowadays give you the opportunity to choose between bright white colour and natural colour, do you know if the materials used in both of them are the same??? i mean the natural components are used in both and the only change is the pigment??

As you know HB has another factory in Cornwall (UK), do you know if i could get Bio-foam there??

Homeblown started out in Cornwall and licenced their chemistry out, chances are they’ll be making it there. Their customer service is great, give them a ring and ask about biofoam, . I’ve made a couple of boards from HB blanks, the’re whiter than they used to be I think. I’ve made shortboards with it and the’re as light as anything else. I’m moving to about 10miles from their factory this summer so won’t have to pay ridiculous delivery charges anymore!

…same stuff white or straw. They said the website under technology is misleading. The foam is getting refined all the time. The difference in price is $4 to $5 from U.S. Blanks here. I don’t know who else is supplying Spain…probably France. I’ll be in Paris in July and check stuff out then. As far as the U.S., San Diego is the board capital in the west, and Florida on the east coast. EPS is available all over the world but you may be getting non virgin unstabilized packaging foam…quite different from what Marko Foam is doing here in CA.

So it seems that this foam might have come to stay huh… Do you shape high performance shortboards? How do you feel the foam goes for that sort of product, where a light and a well balanced flex pattern are the main features looked after? I guess if AL.M. is getting 100 blanks a week, they are good for short boards…

Unless he is using them mostly for cruisier shapes…

Just wondering what price range the blanks are too… for a 6’6" for ex., how much is the unitary price?


Were did you get this machined? Are you in U.S. or elsewhere? How much did they machine for you and what price for what size board?


Yes, I shape everything. Al isn’t a real big producer of longboards and funshapes so I presume the bulk of them are shortboards. Actually it was HB that told me what they were trucking to Merrick, but these guys are real straight shooters and it would be very easy for me to just ask Al and he would tell me if it wasn’t true. As far as price, I don’t know where you are located. I get blanks from San Diego and they are several dollars more than U.S. Blanks (which is TDI and a lot of the guys from Clark ended up there as well as a fair share at Walker Foam).

Some people swear by Walker’s Foam and I was told Harold sold his formula to China. I don’t want to get going on American’s selling us all out to China for a few to get rich (maybe) and the rest of us to lose our homes and not send our kids to college. Yes I know “everything is for sale”. All I’m gonna say on this subject is that China is like the drug dealer that gives someone the first few lines or tokes for free…then later the price will go up and all the experienced master craftsman are gone. Bush is a moron who has helped and promoted all this outsourcing…even the hardworking Mexicans will be out of jobs. China sucks. I’m old enough to remember how much they would liked to have nuked us…instead they will just economically nuke us. Look at their record on human rights, and they suck even more! CHEAP COMES WITH A PRICE! All non domestically roduced products need to be labeled "made in China, Vietnam, Thailand, Mexico, Africa, Taiwan, etc. Surfboards should be no different than staplers. Enough said.

As far as U.S. Blanks, they appear to be doing a very professional job. Ted Wilson of Fiberglass Hawaii was asked, and came on board, as a partner in that company. Ted is a very knowledgeable and successful person in the materials business. A major player that will be there for the long haul if all other facets are worthwhile. If you are fortunate enough to be near a Fiberglass Hawaii outlet you have an extensive inventory of product and tools to choose from…the ony bitch I have is their website is still basically non-existent, which for a company of this stature is inexcusable.

Going back to Al’s stuff, the only thing I’m not positive about is if they are machined first down south by KKL or ? or since C.I. was sold to Burton if they are machining in SB…probably not, but I’m not a C.I. groupie (I started shaping when Al was starting)…so don’t take my word as gospel. I don’t really know nor care.

Personally, the flex awareness is a cool thing everyone is hip to these days. I used to mention board “fatigue” to customers and friends back in the 80’s and it went right past them. I got the awareness after snowskiing. The only one that was big on flex was George (Greenough) who is another friend that is originally from Santa Barbara (my hometown) but for the most part lives in OZ since his dad passed away and the windsurfing craze subsided (Greenough was one of our windsurfing crew).

Anyway, Homeblown foam seems good…I just wish I could blaze through it faster w/out cheddar (tearing). If you get everything machined then this is a moot point. If you handshape, just start w/40 or 50 grit and go up from there. As far as flex patterns…remember that you greatly affect flex with stringer and glass choice, and even the way you shape the volume in your boards. If snapping boards is a concern, use Warp glass. Cloth is rated by warp & weft (aka fill). Warp runs lengthwise on the board and 2/3rds of the glass strand in warp are woven this way. Nearly all boards break because the bottom stretches and the deck then buckles. When have you e-v-e-r seen a board split lengthwise down the middle?

If you’re using stringelrless EPS blanks, be sure to glass the bottom at least equal to the deck. Thin stringers in EPS are an I Beam, but are also fixed and actually are more likely to snap under load bearing than a stringerless EPS blank that isn’t prestressed with a little stringer and glassed like a PU blank (single bottom double deck). So remember “all things equal”. I’m sure people will take exception to this but if you made them and used them you’d tend to agree with me. The main concern w/EPS is if the fulcrum and span is pertaining to a longboard. Liability for breakage goes way up…but it also does so with PU’s. That’swhere you get into thickness being the deciding factor and sandwich construction, but that’s a whole other story.

Anyway, streams of conciousness. I’m rambling on now…gotta go shape…later!

Cheers mate for that.

China is scarry. We have to join forces in the real surfing industrie and keep it as low key as possible for those suckers.

I am in sydney at the moment and want to give the HB foam a go. Both the bio (straw colour as they say) and the white standard stuff. Will be all machined…

Does anyone know where to find Home Blown in Australia?

So DeadShaper… the boards end up light and strong huh?? (saying a really good glass job was done)

But, how light? would it be suitable for competition short board standards?



You should find the weight comparable to what you’re used to: Burford? What else do you use Down Under? You might find a source on the internet and they may have someone in NZ…but if they’re supplying Kimi’s, than they must be in OZ cuz the volume warrants it…I’ll do a bit of checking and see who and where…aloha.

Oh, as far as the glass…yup, if you are used to double 4 single 4 oz. glassing then you should be pleased with how these hold up…you should also expect to use less resing in the layups. On Mals or longboards, you might want to changing one layer of 6 oz to a 4 oz…meaning if you do a strong board with 6/6deck and 6/bottom maybe consider 6/4 deck and 4 oz. bottom.


You should find the weight comparable to what you’re used to: Burford? What else do you use Down Under? You might find a source on the internet and they may have someone in NZ…but if they’re supplying Kimi’s, than they must be in OZ cuz the volume warrants it…I’ll do a bit of checking and see who and where…aloha.

Oh, as far as the glass…yup, if you are used to double 4 single 4 oz. glassing then you should be pleased with how these hold up…you should also expect to use less resing in the layups. On Mals or longboards, you might want to changing one layer of 6 oz to a 4 oz…meaning if you do a strong board with 6/6deck and 6/bottom maybe consider 6/4 deck and 4 oz. bottom.

Surfblanks green… very light. If the outcome weight wise is the same… than HBlown might be the near perfect foam, huh.

let me know if you find out who’s got them here. Thnks