Micarta first time DIY issue

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Panzerred

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Jan 1, 2015
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First time making micarta, i had some 90 min epoxy that didnt set for about 12 hours. I added heat to get it to finish curing which worked great. But i noticed a bubble form. Once i cut the sheet in half i seen that several layers separated in the middle. I put a ton of epoxy on each layer, and had it pressed. Any ideas on the seperating layers or was it simply heat (150 degrees)
 
Five suggestions:

If you pressed it hard in camping, you probably squeezed out all the resin. Use only the lightest pressure that will hold things in place. Hard clamping creates a glue starved joint.

Sand everything dead flat with a 100 grit finish and glue up for a strong bond. It should also be wiped down with denatured alcohol just before glue up to remove any dirt, dust, or oils.

Mix epoxy using either measuring cups or by a scale. Check the weight ratios, as they are different from the volume ratio.

Mix well for 60 seconds, but avoid whipping in air ... or there will be bubbles in the glue joints.

When mating the pieces, slide them back and forth a few times to get a good spread on the resin and let out any trapped air in the joint.


Note - Applying het may speed up hardening, but it won't solve a bad mix ratio. The joint still will be less strong, and perhaps always a bit sticky.
 
Stacy,

I think he was talking about having trouble making the Mycarta, not gluing Micarta scales to his knife.
 
When I have made micarta, both fabric and paper, clamping the finished product is needed to ensure the air bubbles are pushed out. You don't say if you are using paper, card stock, fabric etc. I have had problems with layers delaminating if I have used card stock that has a glossier finish. I believe the epoxy failed to impregnate the less porous material. I have never had this issue with matte finish stock. Also make sure your card stock is THROUGH died. If it is only dyed on the faces (you can see the edges are white) then when you sand it, you will have white layers in the finished product. hope this helps.
 
you may have had a small bubble in there , and the heat expanded it to a larger size, then it cured. most epoxies take 24 hours to fully cure, the set times differ greatly though. you might try using a roller ( like a smooth hard paint roller) to roll out any bubbles as you apply each layer. note that you cannot make "real" micarta. it is a patented heat press phenolic resin process. the stuff made with epoxies is not the same , but it works.
 
Most of those suggestions apply either way. (except for the pressing hard, which is needed to make a laminate from cloth and such)

I have never seen home made My-Carta that was anything close to what the real Micarta is like, so I don't see the desire to make it unless you are using some sentimental of unusual materials.

My major suggestion for making MY-Cart is to use West System 105 resin and 209 hardener. Most regular epoxies, like the 90 minute stuff, is a binding resin ... not a laminating resin.
 
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Stacy E. Apelt - Bladesmith said:
I have never seen home made My-Carta that was anything close to what the real Micarta is like, so I don't see the desire to make it unless you are using some sentimental of unusual materials.
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I agree. It's a cost/time benefit ratio to me. A lot of people spend more time and money trying to save cost or making something themselves and then end up sacrificing quality, uniformity, and performance in the end.
 
One trick I learned from making fishing rods is when mixing a volume of epoxy is to use a nail to mix the epoxy. You stir the epoxy with the nail head at the bottom of the cup it really mixes the epoxy well and keeps from adding air. You just have to make sure to mix slowly and the nail needs to have a head on it smaller finishing type of nails do not work as the head is too small.
 
I believe that these tips will help You. Always use laminating epoxy, I use diluted one with acetone. It makes glue more viscous but needs to fully cure about two weeks. Use putty knife to spread glue to the layers and push bubbles out from fabric. Put some amount of glue on sheet and spread it from center to edges. It makes uniform layer too and saves glue. Use two mdf plates protected with stretch foil or similar stuff. I use mdf boards supported by "C" shaped steel profiles to keep it straight in pressing process. Put it to the press and press it (I use 8 tons press but stronger press = better results). Use clamps for edges, tighten them as You can. Wait few minutes and do it again, with press too. Do it several times until no glue is pressed out. Let it cure in press overnight. Next day remove it from press and cut ugly looking edges. Let it fully cure before use. Here are some results of My micartas: result1, result2, result3.
 
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Well first off making MyCarta like Stacy says is an exercise in cost analysis to a degree--assuming that you want to make it, Epoxy is the wrong material to make it with. You can use different resins but epoxy is just wrong for that use. You can get bondo Resin at any Home Depot and most car parts stores, and apart from having a darkening effect on your base material is makes a really good MyCarta product. I will state for the record that I agree with Stacy, if the type and color of Micarta is available from a dealer that you want, then I would buy it from a dealer. I make a fair bit of MyCarta myself, and one of the ley items I made, which I would recommend to anyone going to make MyCarta, is to build a UHMW mold/press--I purchased some 1/2x 4 inch material from McMaster Carr, and made a rectangular mold/press, I screwed it together with sheetrock screws, and fitted a top that I can clamp down with bolts to get even pressure across the surface of the materials and end up with a nice even/square piece of material at the outcome.

Good Luck !!--Don
 
Fish30114: Well, could You explain Me for what reason is epoxy wrong (except colors are little bit darker) ? Thanks.
 
Something was wrong with your epoxy. There was no reason that it shouldn't have cured on schedule.

Cheap resin works great, and seems "harder" than epoxy, but I've used both successfully.
 
You mean curing time of two weeks? It needs so much time because I add acetone of certain amount that makes epoxy less dense and makes fabric saturate easier. Next day it is "cured" but flexible (it can be bent by hands). You can cut it by saw but grinding belt will be contaminated and degraded. I have no exact time measured, I usually work in my shop during weekends and it is fully cured probably in shorter time. If I add no epoxy acetone then next day it is hard like a rock. :)
 
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Jesenius said:
You mean curing time of two weeks? It needs so much time because I add acetone of certain amount that makes epoxy less dense and makes fabric saturate easier. Next day it is "cured" but flexible (it can be bent by hands). You can cut it by saw but grinding belt will be contaminated and degraded. I have no exact time measured, I usually work in my shop during weekends and it is fully cured probably in shorter time. If I add no epoxy then next day it is hard like rock. :)
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I was speaking to the OP, but mixing acetone with epoxy doesn't make any sense. This isn't like using thinner in a lacquer. Epoxy doesn't dry, it cures through a complex reaction that reduces its volume as the two compounds form a new one. The final product will never be as strong as the regular epoxy would have been.

http://www.westsystem.com/ss/thinning-west-system-epoxy/
 
Interesting reading but I don't use West System epoxy. I believe that their recipe is patented and is slightly different to epoxy I use. I made My micartas for years ago and no shrinkage or cracks are noticed. BTW: Our epoxy is volume expanding while curing.
 
Jesenius, the reason Epoxy is the 'wrong' choice is that it is for gluing things together, not casting them, in larger chunks I'm not sure of the actual functionality of epoxy--it may do fine if you impregnate whatever your forming up, but there are many casting materials that are intended to create things like knife scales--Alumalite is a leading one, and there are many different types of resin--including 'Bondo' as I mentioned--if you have had good luck with epoxy, go for it! I just feel that materials that are intended to make things like you are making is a better solution.

Respects--Don
 
I see what You think. There are many types of epoxy on the market for different use. I use laminating epoxy meaning that epoxy is intended for making boats or other subjects. This epoxy is commonly used for laminating for decades and no problems were found yet. But well, I'll try some other types of resins in the future. Thank You for Your effort. :)
 
"mycarta" is not a casting, but a laminating process. Either fiberglass resin (bondo) or epoxy will work.
 
Fish30114 said:
Well first off making MyCarta like Stacy says is an exercise in cost analysis to a degree--assuming that you want to make it, Epoxy is the wrong material to make it with. You can use different resins but epoxy is just wrong for that use. You can get bondo Resin at any Home Depot and most car parts stores, and apart from having a darkening effect on your base material is makes a really good MyCarta product. I will state for the record that I agree with Stacy, if the type and color of Micarta is available from a dealer that you want, then I would buy it from a dealer. I make a fair bit of MyCarta myself, and one of the ley items I made, which I would recommend to anyone going to make MyCarta, is to build a UHMW mold/press--I purchased some 1/2x 4 inch material from McMaster Carr, and made a rectangular mold/press, I screwed it together with sheetrock screws, and fitted a top that I can clamp down with bolts to get even pressure across the surface of the materials and end up with a nice even/square piece of material at the outcome.

Good Luck !!--Don
Click to expand...

I use Polyester resin ...............it s cheap and If polyester is good for boats , it s good for handles ..... :)

This one is made from seat safety belts and is solid as rock .........

2mes6tz.jpg

315hagn.jpg

162a4xl.jpg


Another one ..

m8gwhs.jpg


This one is mix ...........my hair and hair from my two children ............ waiting for blade , I have no idea how it will look :)


152gkcx.jpg


PS . For quality is essential good soak and high press ...........
 
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There are a lot of good reasonable comments here on the subject. I do not make my own scales but rather buy Micarta but my one worry about using these various products to laminate linen or paper is that you will have to grind the end result and you don't necessarily know what gases or particles will do to your lungs and skin. This may be obvious but I run high speed fans close to my discs and belts to keep from breathing or touching the dust not to mention the vacuum under my disc and belt. I refuse to grind carbon fiber because of the health hazard. Just be careful guys...gasping for breath is a tough way to go. Larry
 
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