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ExpatAussie
August 29, 2014, 16:16
Hi folks,

I'm sure this has been asked before, but here goes.

I'm working on my Ishapore Enfield restoration. I noticed the read handguard has a hairline crack in it, and I whilst it is minor, I'd like to KEEP it minor.

The front handguard has been repaired previously with what looks like epoxy on the inside. I thought I'd try the same "smear the inside liberally with glue" technique on the read handguard, but when looking at the directions for the Epoxy glue, I read "Make sure the surfaces are free from oil and grease".

I've just spent the last three days stripping and oiling the wood with BLO, using the technique laid down by JB White in this post:
http://www.jouster.com/forums/showthread.php?28540-SmLE-what-type-of-finish-on-the-stock

So the surfaces are positively impregnated with Oil.

Anyway, will I have to strip back the handguard, repair it and start over, or is there some secret armourer repair method I can use?

TerryN
August 29, 2014, 16:38
Take your Dremel with a carbide burr in it. Rout out the crack from the underneath until you've got a good groove for the epoxy to lay in. Degrease the area thoroughly with acetone; you want teh wood positively D-R-Y. Apply epoxy and place a piece of tape over it; let it sit for 24 hours. Remove tape, do any touchup sanding necessary. Touch up BLO - one of the positive aspects of that as a finish is that it's really easy to touch up whenever needed.

If the crack is really bad, drill a small 'stop-hole' at the end of it, and fill that up with epoxy when you apply it. You may also need to spread the wood gently with a razor knife to insure that the acetone gets down in the crack to dry that area out. You can force epoxy deeper into the crack by using canned air to blow it down inside. Masking tape on the top side of the crack (and stop-hole) will limit any unwanted migration/seepage of the epoxy onto surrounding areas.

easttex
August 29, 2014, 20:04
I like Brownells Acra-glass or Acra-gel for this. It's made for gun work and it relatively fool proof to work with.

gunplumber
August 30, 2014, 11:06
The factory way is with cross-grain slip patches, but then, cosmetics were not the goal. Don't use epoxy. Use wood glue - it's much stronger. Yes, regular old Elmers wood glue is stronger than 5 minute epoxy on wood.

Guy-epic
August 30, 2014, 13:28
I like the gorilla glue personally but any wood glue is the better fix IMO. I enjoy wood work, and I have seen properly joined wood with just glue break on either side of the glue, never on the glue Sean when done correctly. A glue seam will break if it's not cleaned properly. Also I am a big fan of a tiny hole at the end of the crack. We use that in fiberglass, carbonfiber , and plastics as well. I just salvaged a junk AK upped grip that had a hair line crack. I only drilled thru the back side leaving about 10% of the wood not drilled on the outer side as a test to see if it would keep it from spreading. I didn't want a hole in it. It bad enuff the crack still is kind of visible but strong

Gazz
August 30, 2014, 22:34
Elmers is good stuff but realize that it will soften if it gets damp or wet - maybe not the best choice for something that may get used in the rain. TiteBond is similar stuff but more resistant to moisture.

L Haney
August 31, 2014, 08:34
The factory way is with cross-grain slip patches, but then, cosmetics were not the goal. Don't use epoxy. Use wood glue - it's much stronger. Yes, regular old Elmers wood glue is stronger than 5 minute epoxy on wood.


Aliphatic resins (wood glue) are stronger than the wood for most repairs. If the film thickness is correct. They are not made to fill a void. Epoxy is better for this.

Accraglas will fill voids. You can come close on a color match by stirring in some sawdust from the work piece. You can make some with 80 grit paper from a place that is covered or otherwise not exposed when assembled.

I like stop drilling cracks too.

John A
August 31, 2014, 09:00
For a hairline crack on wood, I use super glue.

My first gun (Stevens 16 gauge that my Dad had gave to me) developed a crack in the buttstock near where it meets the receiver probably 25 or 30 years ago.

Superglue on the inside crack has never came loose or failed, and I used that gun a lot up until recent years.

gunplumber
August 31, 2014, 10:01
Elmers wood glue is not Elmers white glue. Got to compare apples to apples. Neither Titebond, Nor Elmer's wood glue is water proof.

Titebond II and Titebond III have water resistance, as does Elmers Glue-all.

I tried to disassemble some oak rifle racks I'd glued together. The wood split before the glue seam did.

And yeah, I've used gorilla glue as well. Worked pretty well, but a little more cleanup.

I don't like acraglass at all, but Marine Tex doesn't come in brown. If it's not visible or it's getting painted, I'll take marinetex over acraglass every time.

I use epoxy in laminated wood.

http://www.arizonaresponsesystems.com/wp/stockrepair-01.jpg

http://www.arizonaresponsesystems.com/wp/stockrepair-03.jpg

marine tex
http://www.arizonaresponsesystems.com/wp/win94stockrepair-02.jpg

http://www.arizonaresponsesystems.com/wp/win94stockrepair-01.jpg

Guy-epic
August 31, 2014, 11:11
Mark you don't think the extra cleanup which is minimal with gorilla glue is worth it? I do

gunplumber
August 31, 2014, 11:20
Mark you don't think the extra cleanup which is minimal with gorilla glue is worth it? I do

For big stuff that is load-bearing, yes.

For little stuff like FAL handguards - I'm undecided.

SAFN49
August 31, 2014, 11:35
Mark, if you want to disassemble wood that has been put together using wood glue you need to get some syringes and inject alcohol into the joint.

If you don't want to route out the crack I have used GET ROT penetrating epoxy. Just make sure the wood is clean and dry.

http://www.jamestowndistributors.com/userportal/show_product.do?pid=2093&engine=adwords&keyword=get_rot_wood_repair&gclid=CPXuuo33vcACFc1_MgodN3oAzQ

Guy-epic
August 31, 2014, 11:56
For big stuff that is load-bearing, yes.

For little stuff like FAL handguards - I'm undecided.

Fair enuff I think it's just one of those thing that I have started to have really good luck with it, so I like it better. I am doing more wood work lately so I think your skills get better and you start to use what you know well. I know for me that is Gorilla glue. It may not be any better just that it has worked out well for me. So why change it if it ain't broken? Maybe I need to step out of my comfort zone and try a few new things as I do more work?

gunplumber
August 31, 2014, 12:06
Fair enuff I think it's just one of those thing that I have started to have really good luck with it, so I like it better. I am doing more wood work lately so I think your skills get better and you start to use what you know well. I know for me that is Gorilla glue. It may not be any better just that it has worked out well for me. So why change it if it ain't broken? Maybe I need to step out of my comfort zone and try a few new things as I do more work?

I'm in the same boat. The problem is, if I have some widget that needs to be repaired, and it's important, then it needs to come out right the first time. So do I use what I know works, or experiment with something that might be better, but may also give unsatisfactory results?

I have a philosophy that when I'm working on a simple task of little importance, I make it harder (new technique, new products), so that I have practice for when it does matter. Thus the oak tool holders throughout the shop and in all my drawers are works of art - because they don't matter, but give me an opportunity to practice techniques.

I have some gorilla snot around here somewhere - next time I'm gluing something that doesn't matter, I'll play with it more.

tdb59
August 31, 2014, 13:30
Aussie grip ( Coachwood ) with Black Walnut panels and rear fillet attached with Acraglas.

The grip was soaked in lacquer thinner, rinsed with denatured alcohol prior to the layup.

The dyed Acraglas was applied to all surfaces before clamping.

http://i61.tinypic.com/2uop0rr.jpg


.

randy762ak
August 31, 2014, 15:14
Don't use epoxy. Use wood glue - it's much stronger. Yes, regular old Elmers wood glue is stronger than 5 minute epoxy on wood.

With respect=I have found that the 60min Epoxy is strongest! In Fact I have repaired many broken off stocks with it and My brother who builds musical instruments repairs broken guitar necks with it,, I agree the 5min epoxy is not strong!




In this guys case Id degrease the area and using a finger force some 60Min epoxy in the crack and rubber band it tight over night!



I used it to bond 2 stocks that were cut to make a 22 in 03 carbine from a sporter-


http://i134.photobucket.com/albums/q81/randy762ak/RIFLES/secondtryonpics030.jpg (http://s134.photobucket.com/user/randy762ak/media/RIFLES/secondtryonpics030.jpg.html)


And to repair a broken out area in an M1 Garand stock->



http://i134.photobucket.com/albums/q81/randy762ak/RIFLES/Picture1244.jpg (http://s134.photobucket.com/user/randy762ak/media/RIFLES/Picture1244.jpg.html)

Repairing a broken butt cap on a 1903 A chunk was broken out and I epoxied a piece of like wood aligning the grain and you are hard pressed to find the repair,,


http://i134.photobucket.com/albums/q81/randy762ak/RIFLES/RIFLES023.jpg (http://s134.photobucket.com/user/randy762ak/media/RIFLES/RIFLES023.jpg.html)


I use devcon when I can get it--I like it best!

Again I agree the 5 Min. Kind is week!

Guy-epic
August 31, 2014, 15:56
I'm in the same boat. The problem is, if I have some widget that needs to be repaired, and it's important, then it needs to come out right the first time. So do I use what I know works, or experiment with something that might be better, but may also give unsatisfactory results?

I have a philosophy that when I'm working on a simple task of little importance, I make it harder (new technique, new products), so that I have practice for when it does matter. Thus the oak tool holders throughout the shop and in all my drawers are works of art - because they don't matter, but give me an opportunity to practice techniques.

I have some gorilla snot around here somewhere - next time I'm gluing something that doesn't matter, I'll play with it more.

That's the nice thing about this being a hobby not a job. Your customers expect it perfect, and I respect that. Mine are me, and friends that I do things for practice. So I can get to try things at their expense. Which I still find myself wanting to do great work, so I get stuck in a rut of doing things the way I know works. But I have a rhode project up and coming that I am taking very serious. I am doing test samples for him this week, and trying some new distress techniques as well. I have read your posts on it and will be using many of your kindly shared info. It gives me a head start at least. I still find myself wanting to just plug holes and drag it down the beach.

gunplumber
August 31, 2014, 16:25
the longer an epoxy takes to dry, the stronger it is. Thus 60 minute epoxy is stronger tha 30 minute, which is stronger than 5 minute.


The test (fine woodworking) included

PVA water resistant (Titebond III)
PVA Interios (Elmer's Carpenter)
Polyurethans (Gorilla)
Slow set epoxy (T-88)
Hot hide glue (J.E. Moser's)
Liquid hide glue (Old Brown Glue)

Nine samples of each were tested - a tight, snug and loose fit in maple, oak and Ipe wood. The results were averaged.

Testing was done at the Dept of Material Sciences lab at Case Western University.

They were placed in an Instron testing machine. The computer recorded the force it took to break each open mortise and tenon joint (bridle joint) which was selected because the joint itself has no strength. Only the glue held it.

The following results are in pounds of force to break, and percentage strength relative the top scorer.


2024 100% Type I PVA (water resistant)
1994 99% Slow Set Epoxy
1924 95% PVA (non water-resistant)
1595 79% Liquid Hide glue
1531 76% Hot hide glue
1164 58% Polyurethane

The tester's were surprised at the abysmal performance of the Gorilla glue.

And while the slow set epoxy scored almost as high as the Type I PVA, the interior PVA scored as best value for it's dramatically lower cost for non-water environments.

L Haney
August 31, 2014, 16:54
They were placed in an Instron testing machine. The computer recorded the force it took to break each open mortise and tenon joint (bridle joint) which was selected because the joint itself has no strength. Only the glue held it.


Mark, was the test a straight pull of the tenon out of the mortice?

gunplumber
August 31, 2014, 17:30
straight push of the two legs forming the 90 degrees.

You need to pay to see the whole article, but the intro shows the setup.

http://www.finewoodworking.com/how-to/article/how-strong-is-your-glue.aspx

Guy-epic
August 31, 2014, 22:01
Wow I guess it's time to toss the Gorila Glue out. I am shocked as it hasn't ever failed me. My only complaint is the clean up after it dries but I had some tricks for that. Thanks for the info, I am surprised. Also if it isn't good then I am happy to know.

alphadog58
September 02, 2014, 16:44
Being a boat guy I always have some West System epoxy laying around. I use their 'fast' hardener, which makes the epoxy fully cured in about 6-12 hours. I use their 404 structural thickener in different amounts depending how runny or putty-like I want the consistency to be. Also you can color the epoxy with any pigment that's compatible with gelcoat.
Larry

nearmisses
September 05, 2014, 15:37
I'd go with about 100% of what TerryN said. I would use Acraglass gel, drill the crack at both ends, route it out with the bit as TerryN said and use the tape on out side to keep the gel in and inside after applying with syringe while opening with the razor knife, dye appropriate color. I fixed many a broken stock with Acraglass gel and never had one ever come apart again. One on a fine piece of English walnut completely broken thru the grip. Another a piece of Bastogne I told the customer would break in the area it did if used for a one piece stock. You'll need the acetone to de-oil the wood to get a decent bond. The only glitch I would be concerned with would be the de-oiling.