Veneer thickness

General Discussion
1

I am gearing up to do a veneered board and have a few questions for the veneer guru’s.

How do you deal with different thickness veneers or do you just buy veneer that is all the same thickness?

The veneers I bought vary in thickness, when laminated the surface isn’t flush. I would have to sand/plane the surface flush which would be a nightmare since I plan to use epoxy and it more than likely will leak thru the seams to the surface of the veneer while vac bagging

Does anybody care to share how to wrap veneer around rails or am I insane to even consider that?

Last question is there some guide or webpage somewhere on veneering a surfboard? All the veneering books I can find deal with flat surfaces, the compound curves of a surfboard are way more challenging. I can’t find much

FYI I have been reading every thread I can find here on veneering a surf board over the last few days. I bought some fiddleback maple, koa, and doug fir veneers to practice cutting, veneer taping, and veneering to small test cores. I’ve been making surf, windsurf, and kitesurf boards for almost 20 yrs. Tried a lot of processes and cores, poly/clark foam & epoxy/eps, from hand layups to full sandwich EPS/divinicell to vacuum infusion. I have a slight problem/addiction shared by many here in that I can’t do the same thing more than two or three times then I have to try something else (CNC and a pneumatic press are calling in the distance…)

Thanks

Mike S

2

How do you deal with different thickness veneers or do you just buy veneer that is all the same thickness?

The veneers I bought vary in thickness, when laminated the surface isn’t flush. I would have to sand/plane the surface flush which would be a nightmare since I plan to use epoxy and it more than likely will leak thru the seams to the surface of the veneer while vac bagging

Does anybody care to share how to wrap veneer around rails or am I insane to even consider that?

Last question is there some guide or webpage somewhere on veneering a surfboard? All the veneering books I can find deal with flat surfaces, the compound curves of a surfboard are way more challenging. I can’t find much

FYI I have been reading every thread I can find here on veneering a surf board over the last few days. I bought some fiddleback maple, koa, and doug fir veneers to practice cutting, veneer taping, and veneering to small test cores. I’ve been making surf, windsurf, and kitesurf boards for almost 20 yrs. Tried a lot of processes and cores, poly/clark foam & epoxy/eps, from hand layups to full sandwich EPS/divinicell to vacuum infusion. I have a slight problem/addiction shared by many here in that I can’t do the same thing more than two or three times then I have to try something else (CNC and a pneumatic press are calling in the distance…)

I don’t make any claims to be an expert, but I have done a fair share of veneer work. Most veneer work is done for production furniture- veneer over MDF- and so thicknesses are pretty standardized.

But, yes, flats are easy compared to compound curves. For practice its always good to imagine- or actually use- a sheet of stiff paper over a compound shape. It helps to determine the limits to compounding.

At some point you may need darts and/or splices, but its best to avoid them.

I found that my shaping for veneer boards changed a bit to accomodate the skins, and they’re much fairer, friendlier shapes than a pu/pe thruster.

As far as wrapping rails, its not really possible to go past the apex of the rail, and its not all that strong. That’s where some sort of perimeter appliance comes into play (hi-density foam, wood, etc.).

3

I only do decks and bottoms

getting the veneer to mold around the rails would require steaming of the veneer and more than likely a

pre vac bagging to premold the veneer to make a shell then when dry glue it on fare it to the perimeter centerline

then repete for the other side

sounds like a pain in the a$$

heres a few of mine

4

true veneering with 1/24" or 1/42" solid or backed veneer requires a solid substrate to adhere to so you need to glass the board first. grain direction is real important

If you’re using 1/16" -3/16" thick soft wood you can just adhere it to the foam with glass or glue.

for the ultra thin stuff and for the compound curves you need relief cuts and steam or veneer softener.

what I do is lay some plastic over the hard substrate core then totally soak my veneer in softener with a spray bottle and vacuum my relief cut veneer skin to form the shape. You need to pre build out your veneer panels with glue and veneer tape into a skin before hand or at least get a slice of veneer wide enough to cover the whole width and wrap needed.

don’t use the paper backed stuff if you can.

once the skin has taken the basic shape you can glue the skin onto the substrate with a roller or vacuum bag and some resin and glass if you want.

make sure you don’t get any lumps or ridges cause you won’t be able to sand the skin very much.

it helps to have an ultra smooth hard surface to attach the veneer to.

you can glass over the sanded skin

you can saturate the skin and attach it to the substrate with lots of penetrating epoxy instead of using veneer softener and glue as the saturated epoxy with make the skin almost as pliable as veneer softener.

5

Thanks for the replies, I’ll stick with the deck and bottom and not worry about rails. There is a local hardwoods place with pallets of “real” veneer flitches that are mostly still in sequence, nothing paper backed. The pieces I bought are 2" to 6" wide and 8’ - 9’ long, plenty for the board I’m making

My initial plan was glass the core, then vacuum bag when I laminate the veneer with epoxy, then do the outer glass layers. My original plan was to use veneer tape to join the veneer pieces into a single sheet then laminate it. I’m fairly certain the epoxy will creep through the seams under vacuum and make the veneer tape into a monster to sand off. Is that just the reality? Or do I place the veneer taped side against the core? Or if I go light on the epoxy when applying the veneer will it not be that big of a deal? Can I skip the veneer tape all together? Seems like that is asking for big gaps

So what do you do if the thickness varies? The veneer I have is Fir (1/42" thick), fiddleback Maple (1/32"), and Koa (3/64"). know it doesn’t seem that much but you can feel and see the difference on the test pieces I made, with a gloss coat it will really show. Do you just sand them flush after veneering them on? Sanding woods with different hardness is asking to sand through the softest one. Or do I just build up the finished surface with sanding coats to get it smooth?

6

hi, the easyist way to work if the veneers are are slightly different in thickness is to make the deck and bottom skins first ,pressed or vacuumed over a flat surface,

tape together the veneers on what will be the inside and cut out your rough outline ,have a piece of plastic sheet slightly larger than your outline,lay down your glass to this outline on the plastic sheet , all this needs to be on a flat surface , a worktop or similar,

wet out your glass then lay down the veneers on top of the glass, cover with peel ply of some sort and vac away, when done the all the outside veneers are flat against the glass and any really big differences on the inside can be dealt with after,

i have used this way for a few veneer boards ,

pm me if you want some pics ,they are too big to load here, pete

7

Actually that is what I tried on my first two tests but had air bubbles like mad between the fibergalss and veneer. With my second test I used a small plate of glass that I had waxed for the flat surface, wet out some .5oz fiberglass, placed the veneer on the fiberglass, then when I had it in the vacuum bag I could see what would be the finished surface and squegeed the airbubbles out to the edges. Problem was the bubbles kept coming back, I figure it was air in the wood being sucked out. It might have been caused by the fact that my vac pump was pulling 25"+. I’ll have to try it again with less vacuum. Do you get air bubbles between the fiberglass and the veneer?

So that’s what had me thinking I thought I’d go with the woodworkers conventional approach of bonding the backside first. How much vacuum are you pulling when you make your veneer skins?

“any really big differences on the inside can be dealt with after”

What do you do to deal with the differences? Do you use thickened epoxy so the gaps are filled when you bond it to the core? Do you sand the inside of the veneer so it’s flush? Seems like under vacuum the thin veneers would be pressed to the core making the outer skin uneven

Quote:

hi, the easyist way to work if the veneers are are slightly different in thickness is to make the deck and bottom skins first ,pressed or vacuumed over a flat surface,

tape together the veneers on what will be the inside and cut out your rough outline ,have a piece of plastic sheet slightly larger than your outline,lay down your glass to this outline on the plastic sheet , all this needs to be on a flat surface , a worktop or similar,

wet out your glass then lay down the veneers on top of the glass, cover with peel ply of some sort and vac away, when done the all the outside veneers are flat against the glass and any really big differences on the inside can be dealt with after,

8

hi, if you use peel ply against the inside skin air /bubbles get drawn through the wood, 10 - 15 should be enough, if your air /bubbles can/t escape and you use a lot of vac the bubbles in the cloth get bigger because you are dropping the atmospheric pressure around the bubbles which increases the size of the bubbles,

i hav/nt had any problems with bubbles this way ,just make sure you use peel ply and some breather material so the air can escape,

if you seal the wood first this will cause problems because the air has no path to escape,

i have used a 6 and 4 oz on the deck skin and 6 oz on the bottom skin,

when everything is set its easy to sand any big differences on the inside ,

i use a plastic tape to join the veneers together, its not like vinyl ,its more plastic ,its hard to explain , basically masking tape is a pig to remove so i have tried different tapes until i found one that doesnt stick to epoxy that well,pete

9

I have never had to use small pieces of veneer let alone different thicknesses (that sucks)

but may I sugest what on of the other guys posted about glassing one side with glas and resin against a flat panel

that makes good sense

but let me add that after thats done you could surface the uneven side with a hand plane and a sanding block

You may have allready figured that out, or ,I missed it

I get mine from a veneer mfg’r all paper backed and sometime no glue lines one solid sheet cut to order

and thin like cereal box

10

What is this plastic tape you use? Where do you get it?

Quote:

i use a plastic tape to join the veneers together, its not like vinyl ,its more plastic ,its hard to explain , basically masking tape is a pig to remove so i have tried different tapes until i found one that doesnt stick to epoxy that well,pete

I’m looking for an alternative to veneer tape. I find that when making the veneer panels on a flat surface the veneer tape on what will be the the inside of the skin makes for a bit of a ridge (since the tape aborbs resin and is too much work to remove). I might try electrical tape or packing tape since I have some but would rather use what is known to work.

Thanks

Mike S

11

The early woodgrain Surftechs had some funkiness along the rails. They’ve worked it out to near perfection at this point. I’m really not sure how they do it. My guess is possible a perimeter layer right along the apex… probably using relief cuts and softener for compound curve wrap. This might get feathered out before the deck and bottom skins are applied - overlapping the apex piece. Those would get feathered out as well.

If you look really close on a Surftech, you can see a few minor edges where the relief cuts meet and/or overlap but they really do quite a nice job of it IMO.

12

pre-prepping as pete suggests is the way to go.

differences in thicknesses can definitely be addressed after you’ve pre-fabbed the skin.

if you’re using a soft core (i.e.1# eps), you probably won’t even have to address the differences in thickness as it’ll squish the core a little bit upon vacuum lamination. The only place where it’ll cause you grief is on the rail line where it connects with what I presume will be solid rail pieces.

if you’re using long strips, let me add that if you tape the strips together, the entire length of the skin, then a syringe full of 15 minute epoxy is your friend. Open the side opposite the tape, squirt in a bead of resin the length of the joint, and then put it down on a flat surface, using your finger to smear any of the resin that escaped from the joint. This will have two benefits; 1. you’ll have gotten away from pre-fabbing your FG outer skin; sure, you’ll have pre-fabbed the veneer skin, but not the glass, meaning that you can go for a relatively resin rich outer lam to keep your aesthetics tight; no bubbles at the joint if you insure that you’ve completely filled the gap between the strips. 2. the little bead of excess resin will effectively smooth the transition from one thickness to another.

word to the wise; the woods you are describing are fairly stiff (with the exception of the fir). Any attempts to really get them to wrap around compound curves are likely to result in splitting, even if you use softeners. Think carefully when you’re shaping your blank to insure you don’t have a real curvature build-up. This tends to be especially problematic towards the nose and tail, right as the skin has to wrap down to the rail. Once your skins are pre-fabbed and your blank is done, I highly recommend a dry run; ie set up your vacuum system with all of the layers in it, but without the inner fiberglass, just to insure that you know what pressure you’ll need to get everything to adopt the appropriate curves, and so that you see any areas that will be “problematic” and require relief cuts. Finally, believe it or not, the amines used in epoxy hardeners actually make pretty good wood softeners…now, don’t go applying just hardener to the wood; bad idea, but if you’ve got a slow cure epoxy, warm it up so that it rolls out smoothly, apply to the wood, let it sit for a while, and then apply your glass and wet it out. Trust me; huge differences in the curves the wood will take with this method vs. dry.

hth

13

if your going to rail wrap you will need to use softener and a female mold/call.

you best bet is to make the seam past the rail on the deck or at the bevel on the bottom and then pinline over it.

if you tape the under seam you can trim the overlap with a razor

best to have a slight 1/16 -1/18 over lap and scape the seam flush with a hand scraper

then hand lam it…

you can premold the contour into the veneer using softener then trim the overlap flush before gluing it to the substate

do one side

trim

mark the edge with charcoal or chalk

mold the second side trim along the mark

them apply with vacuum and adhesive

and clean up with a scraper before glassing…

don’t plan on sanding anything 1/24", 1/42" or 1/64" thick with any success hand scraping is better