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Climbing Holds
"Tips & FAQ's Page 2"
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Dave, it depends on the kind of hold you have and how it cracked. If you have a hold that doesn't have a sand-type filler and the crack isn't through the bolt hole, you are doing good (for example I've seen pusher and voodoo holds like this). If you do have the crack through the bolt hole, you may end up recracking it after it is repaired because the compression strength of bonding agents such as epoxy or polyester resin (bondo) is usually less than the material the hold is made out of. I can only guess since the manufactured hold I attempted to fix had a sand filler and it just didn't want to realign well enough, but I'd try using epoxy glue in the double-tubed syringe you can get from most places like Lowes or Home Depot. This is thicker than resin bondo and much easier to work with. Hope it works. Oh, and do a few tests before throwing that massive ten foot dyno.
--Steve
Reply:
6/2/03:
Thanks for the info and insight. I will try the double-tube epoxy. The hold
is a 6"screw-on rail, and the crack is located through the middle screwhole.
The cracked surfaces are very clean and fit together perfectly, however, due
to the location, I have my doubts of finding a lasting solution, but I will
try and let you know how it goes. (Just thinking....in this case, it would
probably be cheaper just to buy a new hold! Oh well..... :-))
Email Q&A: Cleaning out foam in mold
7/14/03: i just made my first mold. it came out pretty well. the only problem i have is that there is still some bits of the oasis foam stuck to the inside of the mold. i tried washing with water and got most of it off, but there is still some present which i fear might affect any holds that i
cast.
Question:
what is an effective way of cleaning this out without affecting the
texture of the mold?
thanks for any help.
Answer:
Hey Matt, I usually just fill the mold with some water and gently scrub it with a soft-bristle toothbrush. Sometimes the foam can get in places the brush won't reach, so I just use a toothpick VERY CAREFULLY AND GENTLY to wipe off remaining foam. As long as you are gentle it shouldn't affect the texture. If the hold is small enough, other times I've just ignored the really small pieces and let some bondo cure on it and pull it out.
Email Q&A: Drinking Straw to Set Bolt Hole?
7/21/03: Hi Stephen, hope this finds you well. I don't know if you remember me, I worte about making holds for my kids' rock wall for the backyard.
I have another question if I may. I bought ten holds t ouse as patterns for the molds, to save guessing how they should look. What If I made the holds out of Concrete instead of
resin.. The cost would be way minimal, and they shoulld be pretty durable? If too rough, I could paint them with concrete stain or something.
Question:
Was thinking of adding a straw to allow for the bolt so I do not have to drill the holds after. Am making the molds now.
What do you think?
Have a wonderfully Blessed day!!!
Fred
Answer:
Hey Fred, I do remember you email and am glad it is working out. For what you are doing it should work fine to just use the manufactured holds for prototypes, but they may tend to be a bit slick. They will not be as easy to hold onto as the manufactured holds. As far as the straw is concerned, I would recommend not doing that. The reason is the hole has to be exactly perpendicular to the back wall and the straw tends to slant one way or another, even if just by one to two degrees. When you bolt on the hold, it might crack or slip a lot. If you can figure out a way to make sure it is perpendicular, go for it, but it isn't easy and can be unreliable.
Take Care,
Steve
Oh, about the concrete holds... this is my next project. I think it would be a huge cost savings to use concrete. for now, you might want to consider using wood rather than concrete since it is easy to work with and is very hand-friendly.
Email Q&A: Use Sand as a Mold?
Question:
1/24/04: Wow!Great site! Very Informative!Congratulations.
Hi,I've been thinking in make my own holds, but I don't want to lost my time making molds. I've been trying with a Dupont Body Filler (here in mexico there's almost impossible to find Bondo, any way is almost the same, I think) and making "cookies" of that, and Wow!, Instant holds!. In order to get the texture, I use a metal brush or something like while the bondo is still not hard enogh, and I gently flick the hold. It seems to work, (I have no try it so hard yet).
But I read that the liquid resin works better, so I want to try it. I read in yor page about sand molds, and I was thinking about it. I want to know if somebody already try it and if that works.
I was thinking that if I use some wet sand I can easily make some molds (Ok, I forgot, here, in my town, I don´t know where to get some clay...), and, If I change the quality of the sand, I get differents textures for the holds (well, this could be crazy, but I have seen that cat's sand comes in diferentes textures, then the idea comes to me...) and i will get unique, realy chip molds for the resin.
This could be work even pushing down any stone (chip design jejeje!) or comecial hold in order to get the mold, or just caving a little in the wet sand to get a personal design, but as somebody said in the prior mail, the incuts seems to be a little hard to do.
Again, I have not try it yet, I want to know if somebody did it already.Thank you very much
Regards,
Adi
Queretaro, Mexico
Answer:
Hi Adi, thanks for the compliments on the site. As I understand it,
you are looking for a way to make the resin holds using the sand
as "instant mold". As you saw I've made some holds I call "cookies"
that way and it works great for jibs/footholds. The problem is, as
you've also seen, sand doesn't form to well to shapes before caving
in.
I have made a hold that has a flat 45 degree incut lip that makes a
ledge type grip on the 45 degree overhang in the gym. This worked
ok, but not spectacular. You are not just limited by how much you
can "mold" the sand, but also that wet sand tends to hinder the
hardening agent to solidify the hold and you end up with a soggy
edge. It dries out, but the texture wears off pretty quick.
As for the cat sand holds, I have no idea how it will work, but at
least your hands will always smell good.
Good luck to you and please let other climbers know your tricks if
you do learn a good sand mold technique.
Email Tip: Baking Up Some 30-Minute Holds!!!
Tip:
7/29/03: I read your site and it helped me save tons of money on holds. Thanx! I also did some experimenting while waiting the 24 long hours for my first
test mold to dry. I decided to form a simple mold out of my homemade
playdough (which i used instead of clay or foam) and then poured the bondo
into it. I put it in my oven at 250 for about 15 minutes then ripped off
as much dough as i could and then cranked it up to 350 for another 15
minutes. When i pulled it out, it was pretty much completely cured. It was
amazingly fast, and completely cut out the whole
wait-1-day-for-expensive-silicone-to-dry phase. The only drawbacks were
that the mold was only useable once, though due to the disposability of
the mold, you can make holds with much more positive space and not worry
about ripping your silicone mold to get it out. The other drawback was
that it was difficult to get all of the dough off the hold, but i'm sure
there's a good way to do that. Overall, I think it was worth it, as this
method takes a much shorter time, it can be cheaper (depending on how many
holds you want to make), more flexible (dont have to have 2 of the same
hold, ever), but you either need to start with the bolt permanently in the
hold or have fun breaking drill bit after drill bit making a hole and
counterbore.
Just thought i'd mention that idea so you could put it on your site.
Peace!
-Brett
Reply:
Thanks for the tip Brett! I must admit, it was a pretty bold move putting that smelly goo in the oven, but it seems that it paid off! As far as getting the dough off, since you are going to dispose of the playdough, spray it with a very light amount of WD-40 or silicone spray before pouring the resin.
Just curious, how did the texture turn out? I've heard when done right, playdough can be really good. Oh, I was also wondering if you noticed more bubbles in the cured hold? Sometimes when you speed up the curing, it doesn't have time to de-gas.
--Steve
Reply:
Thanks for the wd-40 suggestion. I'll try that. The only time I had a
problem with bubbles in the hold was when I tried putting the silicone
mold setup in the oven.
I also tried one without using the oven, and it seemed to cure in still
about a half hour, so i dunno if the oven even helped. I guess i just got
some crazy type of fast-curing resin. Its that bondo polyester resin
stuff. Oh well.
I tried a bit of food coloring to color em up a bit, but it didnt really
do anything, they still came out brown.
The playdough does work pretty well tho, but it can be hard to make the
mold nicely without a prototype hold to form it on, but it can still work.
I'm still experimenting with that.
Also, when I was making one of my holds, i noticed i had made too much
mixture, so i dumped the extra on the tin foil that was over the baking
tray i used. When it cured, i ripped it off, and lo and be-Hold (pun intended), the
texture had a real rock look, like folds etc, that didnt feel bad on the
hands. It was, however, too smooth for my liking but i think a little sand
could solve that.
I'll keep you posted on my findings. I think if i get things perfected
enough i might just sell some on ebay ;)
-Brett
Reply:
Brett, I also usually had a curing time of about 30 minutes, but there is a difference when using the oven from what I've heard. Hit me with a quick reply and tell me if the smell from the holds went away after taking them out of the oven. While curing, holds have that distinct Bondo smell until they are finished, which can take up to a week (even though it hardens in half hour). If the smell is gone, then it is possible you just sped up the curing process.
--Steve
Reply:
Hmm... Looking at all my holds, I believe my favorites are the ones that I
cured in the oven. The rest are okay, but I think the oven really seemed
to give them a nice hard finish for some reason. None of my holds really
smell, but the ovened ones definitely do not. the others, if i hold my
nose close, i can still tell they're made of bondo without even looking.
This could just be coincidence, as there were several factors that were
different with the good oven ones and the mediocre non-oven ones.
After I make the next batch, i'm going to try adding a lot more bondo to a
few so they get a slick surface, and bring them and a few others to the
sandblaster at our warehouse to see if it gives them a manufactured
texture.
Email Tip: West System Microbubbles, Ticket to Texture?
Tip:
8/30/03: Excellent website! My friends and I have rented out a storage unit and built ourselves our own co-op gym. We currently have plenty of holds but there are definitely a few favorite flavors which would be nice to reproduce at home. I have produced a few prototypes to get the whole process down and the plastic mix just right. I used to help a guy build boats out of foam, fiberglass and epoxy;so I have some exposure to some of the stuff these folks are suggesting for the plastic mix. The West System microbubbles might just be the ticket along with a light filler and silica sand. After closely looking at some of the Voodoo holds in our gym and messing aroung w/ some surfboard resin I figured the way Voodoo does the dual texture is they add a second glossy coat of resin to the areas they want smooth after the hold has hardened and been popped out of the mold. I haven't tried it yet but will give you an update. Also it should be further stressed that when pouring the plastic/bondo a respirator needs to be worn. Its an expensive initial investment ($35) considering you are trying to keep it as cheap as possible but worth it in the long run.
Robert
Reply:
Thanks for the compliment on the site Robert! You mentioned using West System microbubbles, some silica sand, and a light filler... what type light filler are you using or would you suggest? If possible, use as many specific brand names as possible (it's what people as me about a lot). Good thought on the surfboard resin. I bet you are right. I notice that there is a line between the rough and smooth areas on the voodoo holds (where they taped the rough area before application). Let me know how it works out!! I'll definitely make the respirator comment nice and bold. It IS more dangerous than most people think... or don't think... about. Look forward to hearing how your hold making goes!
--Steve
P.S. If you do find out that the West System Microbubbles do the trick for getting the manufactured hold feel, that would be a huge contribution to the information I have.
Email Tip: TinSil 75 and Polyurethane for Better Holds?
Tips:
10/30/04: I've followed the instrucions on your site and would
like to add my views to your collection. Starting
with the material, the bondo resin works great, but
I'm thinking of making the move to poly-urethane
(what most professional grips are made of). It's
seemingly more expensive, but I don't know how far it
will go. Polytek recomended to me their poly 1510
with a dry filler (as thier most economical) or thier
1512 (for something even stronger and faster drying).
Have you done any research with poyurethanes?
Also, concerning the molds. The only way I've been
able to get air bubbles out is by using a foam brush
in a circular motion to work the silicone on and into
the model (I'm using styrofoam and green oasis right
now), first in a very thin layer, then later adding
more evenly over the exterior for stregnth. Polytek
has also recomended TinSil 75 for the mold material.
This is more expensive but works out way nicer because
it is a liquid silicone which you pour onto your mold
(surounded with a box or some sort of shape around
your prototype) and it gets every little detail with
no air pockets, a great durrability and easy removal
of your grips from the mold.
These new ideas are more expensive, and I'm going to
see if it proves worth it in the next couple of
months.
Concerning texture, there is of course the technique
of spray gluing sand to the prototype and that of
producing holes with a brush, but also there is a new
material being used called synrock (known to the
scientific world as synroc) which is basically
artificial sandstone that can be sanded down to
whatever texture or smoothness is desired. I might do
some research and dig up the chemicals used (it can't
be that difficult considering the style of writing
employed by the founder)
synrockholds.com/material.html for more info.
If you have any info on poly-urethane, I would love to
hear it.
Thank you for providing the useful information that
got me started into what is now one of my favorite
hobbies. Your site is the best I've been able to
find. Keep it up.
Steve
Reply:
Steve, you are definitely on your way to making hold near or at the level of manufacturers if you invest the $$. Go with vinyl ester resin (a resin sometimes labeled under the catagory of polyester resin) and for detail in your hold use the more expensive molding material (stronger and better detail). As soon as my thesis work is done I plan on developing my own technique unique enough that manufacturers won't considered "copied" so I can post it up for the world to know. Since the method is the money maker (patents), I'm betting I get a few nasty emails since almost all the manufacturers of plastic holds use similar materials and unique methods and keep all of it secret. Oh, good idea with the sand-glue...
As far as the synrocks, it would be great to know the secret, especially if they are not too brittle.
Good luck and God bless,
Steve W.
Follow up Tip: 11/2/04: You are right about the molding material. I've done
the research on that and so far the best I've come up
with price-wise is the tinsil 70-25 by polytek. Did
you know that on the first purchase of each specific
product they discount it. I bought a pound listed at
$30 for $17. Next time I'm going to buy a slightly
different variation in a much larger quantity to take
advantage of the savings.
I'm not really sure about the vinyl. Most of the
climbing hold companies i've been able to reasearch
proudly claim using poly-urethane. It seems like the
vinyl might even be more expensive. Let me know if
you have any specific sources for materials found on
any specific sites.
thank you,
Steve
Reply:
Hey Steve, That is a good deal on the polytech stuff. You will definitely see better hold quality simply because of the increased detail in texture. I'm not sure about the polyurethane, but I seem to remember a company using them for screw-ins because they had amazing resistance to tearing or cracking. However, I also remember them flexing more than the polyester types. Either way, I'm sure it will give you outstanding holds. Thanks for the detailed tips, and please let me know how it goes so I don't spend a fortune finding out what you already know!! (3/19/06 Update: Urethanes and ester resins are the two to use, not vinyl type resins. Don't let my vinyl mistake confuse you.)
Take Care,
Steve
Email Tip: Professional Quality Hold Tips (EXCELLENT!)
Tips:
2/20/05: It was very good of you to post this site to help those climbers out there
create there own plastic.
I have been pouring holds for a couple years now. I have talked with some
commercial climbing companies they never will tell you there exact recipe
however I do know a lot of the ingredients they use.
Here are some helpful tips:
Most commercial holds are made out of either polyester resins (almost same
as Bondo) and the stronger and lighter holds are made of polyurethane
resins. Or rigid urethane. A lot of the companies use both depending on the
type of holds. Most companies have a few different recipes for different
types of holds.
Polyester resins are easier and strong they will do the job with strength
and texture. However they always have an smell and some of the Polyester
Resins (Bondo) are greasy. Also real polyester resins are a whitish color
and you can add color much easier than with bondo.
As for polyurethane it is much stronger and lighter than polyester resins.
It also is odorless and is less toxic. It comes in clear and different
colors and the mix ratio is 1:1, so it is easy to mix. However it is twice
as expensive as polyester. If you have the money and want great holds this
is the stuff.
To get a proper Polyester or Polyurethane look up Plastics in a major cities
phone book or look them up on the internet. There are lots of different
distributors. The real polyester resin does not cost much more than bondo.
Most climbing companies use micro-balloons (micro-bubbles) as a filler. In
my experience I use almost the same amount of resin with the micro-balloons
however the texture is very grippy. You can produce almost an exact
commercial product with just resin and micro-balloons. However any filler
does compromise the strength of the product.
A lot of climbing companies use milled fiber to give you more grip. This
stuff is not something to play around with at your home. It is very bad to
have around as it is little tiny hair size pieces of plastic glass that you
can inhale and get all over your clothes. I do not recommend use of this at
home.
Sand can be used as a filler however it will make your holds heavier and it
does make your holds weaker. Most starting out hold makers use lots of sand.
This is ok but almost all commercial companies stay away from sand.
As far as coloring goes they make resin dyes that can be picked up at most
craft stores. They come in many colors and just a few drops does the trick.
Here is a great site that caters to climbing hold making.
http://www.alumilite.com/howto.cfm?ID=20
If you are trying to create quality rocks just keep at it. You should
develop a recipe and keep track of amounts of ingredients used. This way you
can narrow it down and find something that works for you. It is just one of
those things that you develop over time.
Reply:
Thanks for the tips! I had thought that the sand added strength to the hold, but have also heard the one of the major problems with silica sand is that it settles in the mix and displaces a lot of the resin in areas. One person suggested using aragonite sand since it's light and won't settle. It makes sense that micro-"balloons" wouldn't settle so easily. Good tip! Texture is one of the great mysteries to hold making. The only other thing that would be absolutely neccessary to get the texture other than the casting materials would be the better, more-expensive molding material. That site you suggested is a great site and they will probably make some good money for hitting the climbing market. Just curious, do you order your microbubbles, or can it be found in a common store most people can get to?
Take Care,
Steve
Reply:
There is no way to control how the Silica Sand settles, mostly it settles to
the bottom but it does cause displacement of structure in your resin. Resin
by itself is very strong and when it is broken up with other materials it
causes weak points. I have broken holds made of very little sand by
torqueing on them the wrong way. I have tried almost all the fillers out
there silica beads, milled fiber, sand, etc. There are lots of fillers out
there. The only one that experts say help to increase strength is milled
fiber. I used milled fiber for awhile but due to the fact I am doing this in
my home I got rid of it. However micro-balloons just add little bubbles to
the resin as it hardens. It is said that too much micro-balloons can reduce
strength as well though. Although I have not tried aragonite sand. Let me
know how it goes if you try it.
I forgot to mention that using the right foam to create your rocks makes a
big difference there are many different types of foam, they say to use
floral foam but there are foams that are as easy to shape as floral foam but
have rougher natural texture. These are great for getting a good texture. I
donšt recommend Styrofoam though as it is hard to carve.
Recently I ran into the owner of a major climbing company, One that I
respect as one of the best hold companies around (I can't disclose which
one). He told me a lot about the business aspects of the field but I asked
him about how he started and materials and sand and he said "stay away from
sand." I also learned that most companies have different recipes for
different holds. My other friend has been making holds for about 5 years now
he makes holds for flashed now, he has told me the same things.
Actually I first purchased micro-balloons from a regular model shop in my
town. They use them in the production of model airplanes or something. I
think it is the same everywhere just call up your local hobby shops that
deal with model building. I now buy them from the plastics shop I get my
resin at. As for texture that is something that comes from playing around no
company that produces holds will disclose there recipe. So you just have to
be diligent, the right combination of resin and micro balloons will give you
a professional product. If you have any more questions on the process or
anything just let me know! I love making rocks it is kind of an obsession.
Email Tip: Epoxy User Tips
Tips:
2/27/04: Your site is fantastic. I thought I'd let you know about using epoxy
instead of polyester resin. Epoxy is more expensive, but stronger, and less
toxic (it hardly smells when curing). Here's how I have been making holds:
I use a two-part epoxy, with a 2:1 mix ratio (it's easier to get the right
ratio than a 5:1 mix). I add 3.5 parts dry beach sand to 1 part well mixed
epoxy, just until the mixture no longer slumps when handled (gloves are a
must as epoxy can cause an allergic reaction). Then, using an old plastic
climbing hold display board, I insert regular hex head bolts up through the
holes so the plastic board is laying on a table with the bolts sticking up.
The next part is fast and fun; simply plunk a blob onto a bolt and form a hold.
Before your too far into it, place a washer over the bolt and push
into the epoxy a bit, then finish the hold. Pull out the bolt from below and
that's it! They must be formed on flexible plastic in order to pop them off
when cured. They cure in one to two days depending on
temperature. Heating in the oven after a day or so increases the strength as well, though
placing in the hot sun may be safer. They are very strong and the texture is
great. Also, epoxy is easily dyed using latex paint or tint, though one
would need white sand I suspect. The whole process is so easy and fun, I am
considering making large panels for my wall. A word of warning though, epoxy
varies greatly in price. Shopping around is a must as the price can easily
double. Also, if the weather is wet, an aqua set epoxy might be in order. Dan
(Tofino BC)
Reply:
Thanks for the tip Dan! It sounds like an easy way to make holds and
using the old climbing board would make sure the bolt hole is
perpendicular. Nice. One thing I'm curious about: Texture. How do
you get the final hold to have a non-slick texture? I'm guessing
with all the sand you use it is enough to make it pretty much
automatic. Do you find that the sand tends to rub off or does it stay
intact pretty well?
Also, are you buying your epoxy online? If you are, it would help to
know the site for the readers.
Take Care,
Steve
Email Q&A: Which Floral Foam?
Question:
4/24/04: I've just finished looking at your site, and it gave me a alot of good ideas
for my own holds that I am starting to carve. And you're right, there is
definately a big creativity curve that goes on when first starting to shape
them. You said that you used floral foam a little bit. Do you use the
harder stuff for fake flowers only, or have you also used the softer stuff
for real flowers? and if you HAVE used the softer stuff, has it presented a
problem when casting a mold out of it with the silicone becuase it is too
soft? My other question is how do you deal with taking the prototype out of
the silicone mold if the protoype has a very extreme incut to it? Thanks.
I look forward to showing you some of my holds that your site helped out
with (if any of my holds ever do once I'm beyond the shaping stage.)
-Jon
Reply:
Hey John, I've used both the soft and hard oasis foam and both will work, however the harder is better in my opinion for texture. The biggest thing is making sure you do a good job of blowing off the carving dust before applying the silicone. It plays a huge role in the micro-texture. As for severe undercuts, just make sure you leave some way to get the hold out. I have one mold for a retangular shaped roof hold that has two severe undercuts on opposite sides. For this I made the sides without undercut extra thick and cut a slit down them. This allows a hinging action to pull out the two undercut areas without losing the mold. I hope this made sense. Also, you can look at molding idea from professional artists (online) for two piece molds and suggestions for making these line up.
Take Care,
Steve
Email Question: Need help drilling rocks!
Question:
10/4/04:
Have you any experience with drilling rocks for holds? We have tried a number of fist size rocks and the hammer drill seems to just crack them to pieces. The granite holds are a bear to drill, so we are not having much luck.
Any advice would be helpful.
Thanks,
Cam
Reply:
I don't have much experience in this area. What I've tried with limestone cracked in a hurry (soft rock). I'll post it up in the FAQ section to see if anyone else can reply with a
reasonable answer. I know it's possible because there are companies that sell real rock holds, however I believe those companies use a very specific type of rock and most likely drill it with a press and mortar bit. You might try using a small bit first in a regular drill, then upgrade to the next size to widen it, then again... until you have the right
diameter. The tighter you can fit the bolt, the less stress your rock will have when you grab it (any free space will torque and crack it). Another option may be to use a slightly wider hole, jam a fitting through it the bolt can slide through (like the ones that come with a cement wall screw kit), and then let that fitting distribute the torque better.
Hope you figure it out and let us all know, lots of walls could benefit from your findings!
Thanks,
Steve
Email Tip: Sites for Clay Mold Use
Tips:
2/9/05: I bundled two emails on this subject:
First email:
Hey there great site, i'm just looking into making my own climbing holds and
love the wealth of information. In my quest for knowledge i came upon two
sites that might be helpful to some of your followers as well as yourself.
Using clay as a mold
and dying with acrylics:
http://www.alpinedave.com/misc/holds/hold_making.htm
(another unposted email had this site as well: http://students.washington.edu/dbb/misc/holds/hold_making.htm)
Second email:
3/2/2004: First of all I have to say your site is the BEST site on hold making (believe me I have searched the Internet). I haven't made any holds yet but I was wondering if you have tried using a real manufacutered hold as a prototype? Almost all of the other sites I have seen also recommend using florist foam. One site I stumbled into uses commercial holds to
form a clay mold http://students.washington.edu/dbb/misc/holds/hold_making.htm . Let me know if you have any thoughts or experience on this. Thanks. - Fred
Reply:
Thanks for these sites! The first is a great way to make quick dups of the manufactured holds, but I do wonder how much it copies the texture. Have you tried it? The second site (Alumilite) uses similar materials to what the manufacturers make their holds (although it can be argued that adding a filler actually adds strength to the hold while cutting the cost). Not exactly the news Alumilite would want to give a customer using their resin. It's $$$ for the mold, but the molding material is RTV, MUCH better than GE kitchen/bath stuff for getting the right texture.
Excellent site.
Take Care,
Steve
Email Tip: Making Plasteline Prototypes
Tips:
2/14/05: Hi Steve! First of all a big "respect" to you, your site is pretty cool. I started producing climbing holds myself several months ago. I use an epoxy- material which I mix up with sand and dye. My models for the molds are made of a (not sur what you call it, we say Knete, maybe its Plasteline???) mass I mix meyself. (Very easy, 600g flour, 200g Salt, 12 g Alaun (from the pharmacie- that's what's being used in blood-stop-sticks) half a Liter of boiling Water and some colour- baking- colours for example- put it in a bowl and mix it all over. If it becomes a little bit rough on the surface, just put it in a tupper an add some water)First I made Molds of silicon- but they were not as I expectetd them to be, there was some air shut in, wher the single "worms" of silicone met. First question: Do you konw a way to make silicone mor fluent? I tried a lot, but I have been unable to create molds without these sharp edges in them. Now I use latex. it stinks a little more, takes a little longer because you have to "paint" it on your model in several layers. But the inside surface is much better. The only disadventage is, that these molds are very very flexible. You can't stand them in a box fillesd with sand, they just collaps. And if you make them strong enough, it costs a lot and takes even more time. I solved this by building some kind of frame around them and filling this with (we kall it Gips) liquid- concrete. When I want to use a special mold, I put it in its form, in its block of concrete and then....But- here it is, the "but". I haven't yet figured out, how to make a real good, rough surface. I've tried different kinds of sand, changed the dosage, but my surface is still much too smooth. Would it be a possibility, to pu an additional layer of ground, sand and colour on the holds (like you use when you self- make boulderwalls). Our has the surface inside of the mold to be allready very rough? Or is it that I have to use even more sand- then the "mass" is no longer pourable. OR different sand? Mix the sand?
Maybe you have a secret tip for me...
Some additional tips from me: I get my epoxy stuff from eBAy, I found a trader who offered me 8,10 Euros per Kilo- if I take more than 10 Kilos at a time- no problemo... ;-) (that is really cheap for our local market, in stores for models and mini- planes and RC- models you pay 25 euros for 350ml....). As dye I use colours, which are near to car-paints. Those are chemical based and not waterbased, and that is very important for the hardening of the holds.
Looking forward to hearing from you soon!
Bernd from Germany
PS.: If you' d want me to, I could send you some pictures of my "work"....
Reply:
Hi Bernd! Glad to hear you got some good info from the site to get started. It sounds like you are running into a limitation with the texture not because of your prototype, or the resin you are using, but a limitation in the details the mold will catch. Less expensive molding materials shrink when they cure catching less prototype detail. I'm not sure liquefying with mineral spirits or heating to reduce viscosity will help in this problem. You will probably need a better mold material (I've heard two-part RTV works well). The solution to this is to use a two-part RTV type silicone that is made to capture the detail you are wanting. This silicone is specialized for mold-making and more expensive, but most silicone companies will send you free samples if you call them and tell them what you are doing. I recommend a two-part tin-catalyzed silicone with a shore hardness of about 25-35 and make sure it comes with a thixotropic agent if you want to apply the silicone to undercling surfaces. Try different methods to get the texture you want on the prototype. Good luck! I think if you try this you will find it helps.
Good Luck. Oh, send pics if you can. It's aways a help to others!
Steve
Email Tip: Bondo Holds White with Swirls!
Tips: 2/20/05
 
Ok, here's some new pictures. For the swirled one, I
mixed up the bondo/sand mixture with some of the white
die, and then just before I poured it into the mold I
swirled in some of the colored pigment. It may work
better to mix the colors in after the white mixture is
already in the mold. I'll have to try that later.
For now, these look pretty good, though.
Matt
Reply:
Thanks Matt! I'll definitely post it! I have one favor to ask.. I can't find your last email to me about where you got the white dye from. I remember you saying there was a specific vendor that had it. Sorry I lost that email. TAP Plastics? I'm pretty sure it was them, they tend to have great stuff. Anyways, if you can remember what you wrote, I'd really appreciate it. I'll post up the hold pics and this email either way.
Take Care,
Steve
Reply:
Yup, it was TAP Plastics. Thanks again for getting me
started on this stuff. I'm addicted!
Matt
Email Tip: "Oasis" Foam?
Question: 8/30/05
I have read your site about making climbing holds at
http://www.stephenwilliamson.com/climbing/climbingholds.htm
This is a very good explanation. With your tipps I have done it myself
in a similar way. At my (German) site www.cmoos.de/sport/kletterwand.html
I have described this way of making climbing holds and mentioned your
name with a link of http://www.stephenwilliamson.com/. I hope you will
find this is okay. If not, I will change it .Please let me know.
I don't think, you can read my site in German. My English isn't that
kind, but I understand your explanations with one big exclusion: So
dammed, what is OASIS. My dictionary says it's the little green in the
desert. So I asked a college , who is an English teacher. But he doesn't
know. So he himself asks Sheila, who is another teacher for English, but
she speaks native English. After some questions she found that, it must
be a little sponge for flowers to keep them wet. Yes, I think, that's
it, that makes sense. Sheila also says, oasis isn't known in America.
After this little story, you may tell me about our solution of a
climber, a German English teacher and a native English speaker in
German.
Ciao
Carsten
Answer:
Hi Carsten. You can certainly use my site as a link if you wish. I would, however, recommend linking directly to www.stephenwilliamson.com/climbing/climbingholds.htm rather than the home page so the reader does not have to search through the site. To answer you question about "OASIS": This is not only a green area in a dessert, but it is also a name given to a soft foam block that absorbs water well for use by florists. The cut flower stem can be inserted into this foam block to both help in arranging the flowers and also to keep the flower stem immersed in wet foam. I suspect you have something similar there, but it may be called something different. I saw from your site that you use a clay or putty for to make the prototype. The only advantage for using the foam is that it has little dips in the foam material that automatically give texture to the hold (for those who do not want to experiement with make a texture in clay). I've had an interesting series of emails that say they have used clay as the mold and poured resin directly into the clay pocket. The neat thing about this idea is that the clay holds MUCH more detail than the silicone (or cheap silicones) can giving the hold much better texture. I have not tried it myself, but suspect as long as the sulfur in the clay does not react with the resin, it would work great.
Good luck to you!
Stephen
Email Q&A: Cost of Urethanes?
Question:
3/1/06: Thanks for the information from your site on climbing holds. I have not had a chance to make any yet. I have just finished making some molds. The question I have for you is about the cost of urethane. I have been on the web site of Alumilite. They have a nice article on how to make climbing holds with there products. They gave a sample formula for calculating the amount of resin needed for a mold. Basically a 4*3*2 in hold would use about 13 oz of resin. This size hold then would cost approximately $15 to make. From what the company said on the phone most of commecial hold companies buy mass quantities of this stuff. This makes perfect sence. Is this just overpriced for the resin or are there cheaper alternatives to make urethane holds? Thank you very much. Dave
Reply:
Hi Dave. Sorry it's taken so long to get back to you. I did some research on the subject of comparing different types of polymers and found some companies that offer either polyester or polyurethane resins. I honestly believe either can be used by manufacturing companies to produce a long lasting hold of excellent texture and quality. If money weren't
an object I'd be using polyurethanes over polyester resins since they are safer to use and awesome in strength and wear properties. However, since money IS the object in this venture, I'd go with polyester resins (clear/white if you want to add color). TAP Plastics, USComposites, and Polytek have some good choices for "casting" resins but expect to pay about 40-50 bucks per gallon. Best price I could find was US Composites Polyester resin for casting ~28 bucks for a gallon minus shipping. I did find an old publication from Polytek offering 1/2 Gallon Trial versions (free shipping) of their EZFlow 120 or 60 casting resins (see this Adobe file:http://www.polytek.com/newsletter/nws28web5.pdf). You should contact them to see if they can get you a current trial. Also, there are ways to cut costs with fillers such as "microspheres" or "microbubbles" (see TAP Plastics). Don't add too much, but this will reduce your volume calculation substantially. Experiment and see what works. As for your molds you just made... unless they are made with higher quality RTV type silicone molding material, don't waste your money on expensive resins. The silicones from Home Depot for bathroom work are not made to catch the details you'll want for your texture. The Bondo/ tube silicone method is the ultra-cheap method to crank out great homewall holds. For more quality matching the manufacturers, get the expensive stuff and figure out how to make it cheaper with fillers that don't reduce the strength too much.
Hope this helps!
Good luck and God bless,
Steve
Top Picture: My cousin Dustin is learning mountaineering skills at McKinley
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