Gunsmithing Any tips for measuring/mixing Devcon?

[Ratbert]

I really wish they'd sell Devcon in a pair of transparent cauk gun tubes like giant syringes so I could just squeeze out the correct, matching amounts of base and activator. But since they don't (AFAIK) I am hoping that my current method of just scooping out approximate sized dollaps from each jar and hoping I have both the right mixture and enough total epoxy for the job is not my best option.

Anyone have any tips on a convenient, reliable way to mix the epoxy so you know you'll have enough for your job without wasting a whole bunch?

 

[Kells81]

Re: Any tips for measuring/mixing Devcon?

I use my wifes cooking scale out of the kitchen

 

[BobinNC]

Re: Any tips for measuring/mixing Devcon?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Ratbert</div><div class="ubbcode-body">I really wish they'd sell Devcon in a pair of transparent cauk gun tubes like giant syringes so I could just squeeze out the correct, matching amounts of base and activator. But since they don't (AFAIK) I am hoping that my current method of just scooping out approximate sized dollaps from each jar and hoping I have both the right mixture and enough total epoxy for the job is not my best option.

Anyone have any tips on a convenient, reliable way to mix the epoxy so you know you'll have enough for your job without wasting a whole bunch? </div></div>

Ratbert,

The Devcon Fairy told me your wish has been granted:

Sold Here: Ace Hardware

 

[Ratbert]

Re: Any tips for measuring/mixing Devcon?

Hmm, has anyone used that for a bedding job? It appears to be a 1:1 mixture, so I wonder how it compares to this:

which if sold in caulking tubes instead of the little jars would be really easy to dispense a relatively precise amount for whatever size job you were doing.

I'm having a hard time envisioning what a 1oz tube would look like mixed (does it make 2oz of compound, or 1?) but I'm guessing it wouldn't quite be enough for 1 tube per job.

But maybe (hopefully) I'm wrong and this is just the ticket.

 

[jrob300]

Re: Any tips for measuring/mixing Devcon?

I feel your pain here, Ratbert. Being ADHD, OCD and near-fatally anal retentive, the first time I used 10110 I nearly had an aneurysm.

I typically mix by volume and then err on the side of more hardener. It always seems to come out just fine. If I get too little hardener it just seems to take longer to cure, but still cures. I'm sure if you got too little it might not. But seems to be pretty forgiving stuff which *might* be why they didn't supply it in rocket science packaging. And yes, I ALWAYS run out of hardener first.

John

Oh, the syringe Devcon that Bob showed, I used that to modify the rear suspension for an autocross car about 15 years ago. Strong stuff.

 

[Hateca]

Re: Any tips for measuring/mixing Devcon?

Not going into the detail of this but a few years ago I had some contact with Devcon about tinting the product, which you can, and some other issues.

The instructions can be confusing as hell for some with the instructions about volume and weight and a 2.5 to 1 or something like that.

Just use two parts putty to one part hardener and you will be fine. Meaning two tablespoons of putty to one tablespoon of hardener.

 

[HugoStiglitz]

Re: Any tips for measuring/mixing Devcon?

As that I have worked as an engine machinist and restoration fabricator since '84, I have used ALOT of Devcon for many uses, including repairing badly corroded rare gas tanks. I have never had a failure with proper surface preparation. I have ALWAYS mixed by volume and have always done it by "EYE" so I think you may be sweating "The Small Stuff" by worrying about EXACT ratios. Once you open that can of resin it will form clumps over extended periods that may not always mix smoothly. I smooth external applications by wetting a finger and smoothing it out, water does not affect it, unless you use too much. This is where the chunks can become evident. Industrial Devcon is Not mixed 1:1 by weight or volume, so I don,t know what the formula for that stuff in the syringe is? I always save the pallet I mixed on so that I have a sample to assess for Quality Assurance. Have bedded numerous actions with Devcon, BEST stuff out there (usually do it a 2nd time to fill voids for a good look). I use Kiwi neutral shoe polish for a release agent and modeling clay to fill larger areas. JB WELD sucks as it has NO body and will run down-hill when applied, unlike Devcon. YMMV

 

[GasLight]

Re: Any tips for measuring/mixing Devcon?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HateCA</div><div class="ubbcode-body">
Just use two parts putty to one part hardener and you will be fine. Meaning two tablespoons of putty to one tablespoon of hardener.
</div></div>

You feel the 3 tablespoons is enough to do 1 rifle?

Thanks

 

[Ratbert]

Re: Any tips for measuring/mixing Devcon?

I think I might have been unclear in my first post. I'm not overly concerned with achieving exact dispensing ratios or anything, I've certainly never seen anything wrong with the final product when using Devcon measured by eye. What I really hate is the actually scooping, smearing, glopping, etc when trying to get the putty out of the damn cup in any controlled way. It sticks to everything so well it's nearly impossible to get it off your scoop, so I end up using multiple scoops (usually popsicle sticks) and then once i've got properly balanced glops out of the cup inevitably it's not QUITE enough. This is what I'm trying to avoid, any accuracy in measuring gains are just icing on the cake.

 

[Raven 6]

Re: Any tips for measuring/mixing Devcon?

Well for me the putty is harder to get out of the cup than the hardner. So I use an old case knife I confisated from the kitchen drawer for the putty and a pop sickle stick for the hardner, that way you don't get the putty in the hardner cup. Does that help any?

 

[Hateca]

Re: Any tips for measuring/mixing Devcon?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DebosDave</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HateCA</div><div class="ubbcode-body">
Just use two parts putty to one part hardener and you will be fine. Meaning two tablespoons of putty to one tablespoon of hardener.
</div></div>

You feel the 3 tablespoons is enough to do 1 rifle?

Thanks </div></div>

It all depends on the bedding job, receiver, stock, barrel pad, and so on. Normally I use two tablespoons of putty to one tablespoon of hardener. If I think I will need a little more I may add a half tablespoon of putty and one quarter tablespoon of hardener.

I have never needed three tablespoons when doing a barreled action with bottom metal. Single shot actions with more surface area, yes you might.

Thing is if you haven’t done a lot of bedding it’s hard to tell at first. It’s better to have too much then not enough. After bedding a few you will get a feel for just how much you need.

I don't use cups to mix, that makes a mess. I use simple paper plates. If you wish to tint the Devcon just about any epoxy tint will work but I use the stuff from Brownells.

Popsicle sticks are too small, I use tongue depressors and special applicators I made.

 

[HugoStiglitz]

Re: Any tips for measuring/mixing Devcon?

That syringe is just a dispenser, you still have to mix it for use. Once mixed, Devcon would probably cure in a vacuum. Just thinking "out loud" here, but if you could find larger empty syringes with a big bore you might just be able to spoon the Devcon inside and inject it onto your project. Have never had a problem bedding the stocks I have done, just careful application, a little at a time to keep air pockets to a minimun, use masking tape on the stock and release agent on the action. Even if you are a little sloppy, it all cleans up in the end. P.S. I find that I usually end up mixing 50% more what is actually needed, as I'd rather have too much, than not enough. YMMV

 

[Scimitar]

Re: Any tips for measuring/mixing Devcon?

I buy the measuring spoon sets at the dollar store. Cheap and easy and you know that you have the mix right.

 

[MontanaMarine]

Re: Any tips for measuring/mixing Devcon?

I use the 10110 product, and just eyeball it, scooping with a wooden hobby stick. Works great.

 

[m1k3]

Re: Any tips for measuring/mixing Devcon?

I use my digital powder scale and just weigh it out, 9:1.

I set the scale to grams.
Using the bottom 1/4 inch of a plastic cup for a tray,
Zero out the scale with the cup on the scale.
I weigh a fair amount of putty in the cup.
Write down that weight and then divide by 9.
This is the weight of the hardner required.
Zero out the scale again with the putty and cup on there.
Now add hardner to the mix until the scale reads the amount you figured above.
Done!
Just mix it up and you're good to go.

If you require more epoxy, just use the same cup but zero it out at the beginning and follow the procedure above. It is no problem to just add more epoxy and hardner to the same cup since the ratio should be the same if your math is correct.

Oh, I have also used the Devcon shown above in the syringe. It works but is very messy. It is self leveling and will drip and flow where you don't want it. IT IS NOT PUTTY!!! Same as JB Weld. It works, just not as well as the putty version.

Good Luck!
Mike

 

[dmg308]

Re: Any tips for measuring/mixing Devcon?

It's not that sensitive just like body putty eye ball it a little more or less won't matter it just effects your working time.

 

[bigtater80]

Re: Any tips for measuring/mixing Devcon?

where can you buy the putty? Other than online.

 

[m1k3]

Re: Any tips for measuring/mixing Devcon?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dmg308</div><div class="ubbcode-body">It's not that sensitive just like body putty eye ball it a little more or less won't matter it just effects your working time. </div></div>

I agree its not that sensitive to mixing but in a field/sport where we measure nearly everything in .001", why not be accurate/consistant with mixing the putty?

Its just one method of many but is a method where Batch A will be the same as Batch B and Batch C and . . . .

I'm just a little anal like that I guess when it comes to my guns.

MIke

 

[ArcticLight]

Re: Any tips for measuring/mixing Devcon?

FYI -

If you use a coffee can lid and let it dry overnight the devcon will pop right off of it and you can re-use it...

 

[pklin1297]

Re: Any tips for measuring/mixing Devcon?

I had purchased the syringe Devcon Plastic Steel last week and just today went to test it on a spare Mosin 91/30 bottom metal I had. I wanted to see how runny or solid it is once mixed, and also to test whether my Angelus clear shoe polish would yield the same result as the Kiwi clear shoe polish as a release agent. I had also purchased a silicon mold release spray yesterday to also try as release agent, but the can wouldn't even spray so that is another problem...

Anyway, the syringe product was very easy to dispense and mix, and once mixed, it had the consistency of peanut butter which was very easy to apply and have it stay in place so I was happy to see that as I was hoping to use that for bedding my scope rail. I applied two coats of the shoe polish on a large flat surface on the bottom metal, then polished it off after each coat, then applied the Devcon. 6 hours later, the Devcon was rock solid and by using simply my nails, the Devcon came right off in a solid single piece!

Needless to say I was happy with the result. By looking at the underside of the Devcon I spread on the bottom metal, it duplicated every single scratch that was original on the B.M., but the surface of it was nice, clean and shiny. I will definitely be using this method to bed the base. This weekend I will try the Devcon 10110 in the jar with the shoe polish to see how that work; I expect the same result.

On a side note, I sprayed PAM (and didn't wipe off) on the other side of the B.M. and applied Devcon just like the other side with the shoe polish, and I am still unable to remove the Decvon so I am worried. I won't be using PAM for bedding... I know it has worked for many but somehow it did not work for me.

Hope this helps anyone thinking of using the Syringe product. I loved the ease of dispensing this product and mixing.

 

[Ratbert]

Re: Any tips for measuring/mixing Devcon?

Thanks for the info, I think I may give it a try for a hunting rifle I'm working on.

 

[Trapshooter12]

Re: Any tips for measuring/mixing Devcon?

My Wife works for a Vetranarian and has access to large syringes. I cut the end off with a Dremel and pulled the plunger back and added the amount I needed, it was very simple to do. I wish I had thought of it alot sooner. I wouldn't have wasted so much Devcon on my other Bedding jobs.

 

[ejg]

Re: Any tips for measuring/mixing Devcon?

Don't know how sensitiv devcon is, but with epoxy the strength and hardness goes south if the ratio is not right. It's not like polyester where the catalist just sets off a reaction.
The idea of filling syringes is good, certainly better than a guess.
If the manufacturer won't give weight ratios, the closest guess would be to use the content weights of the containers that are sold as a pack and put that to a ratio.
I use a base resin and hardener that comes with exact weight and volume ratios, mix to a tenth of a gram and then blend in whatever fillers I need. I think safer.
edi

 

[colchester]

Re: Any tips for measuring/mixing Devcon?

I use the scale method also I mixed by volume before I scored the scale at an auction

 

[LRI]

Re: Any tips for measuring/mixing Devcon?

Depends on the type of Devcon.

The titanium stuff works best when done by weight. The stuff I use is based on volume and I use the entire contents of both resin/hardner when bedding a gun to avoid any goof ups.


Good luck.

C

 

[former naval person]

Re: Any tips for measuring/mixing Devcon?

Use less rather than more hardener. Counter intuitive, but if you add way too much it won't set up correctly. The hardener bucket has the right ratios printed on it.

 

[Ratbert]

Re: Any tips for measuring/mixing Devcon?

FYI, I tried out some of that S-6 Devcon in the tubes when bedding a hunting rifle this weekend. The end result was acceptable and appears to be comparable to the 10110 however there were a few differences:

1) When it says 2hrs work time it means it. 2hrs later there was no appreciable difference in it's consistency. You need a MINIMUM of 10hrs, probably closer to 12 to be safe before you should even consider trying to handle it or tap the action out. In general I will only plan on using this to bed things where I'm not nervous about leaving it 16hrs + to fully cure before trying to release the mold.

2) It does not seem to clean up as neatly as 10110 (or at least I haven't found the best method yet.) WD40 does not wipe it clean as well as 10110, though it does work. Do not wait for it to set before attempting clean up. Until it hardens it will become progressively more like chewing gum with tendency to stick, pull, and tear. It doesn't not seem to have that period during hrs 6-8 where 10110 cuts very easily and cleanly with a pen knife.

3) It starts out smoother and more viscous than the 10110, it seems to flow a little bit better than the 10110 though probably not enough to make a difference if you've done it correctly or to fix a large air pocket if you've really gorked it up.


It colors much closer to black vs 10110's dark gray. Johnson's floor wax worked just fine as a release agent. If you are doing a very light skim bedding then you can probably get away with just 1 tube, but a full pillar bedding will require at least 2 tubes, more if you also want to bed the bottom metal or are particularly messy.

 

[ArmyJerry]

Thanks for the info gents, I will bed a savage in a boyds with the syringe tomorrow.

 

[Elite_KG]

Just eyeball it. It is not super sensitive to ratio. However, too much or too little hardener will cause it not to set-up. So try not to "error" on either side. I measured it out in the past but it made a mess of any measuring scoop or container. I eyeball it each time now. 2.5:1 (Devcon steel putty).

 

[Straight Shooter]

I hate Devcon. Why put yourself through the hassle and expense when Marine Tex is stronger than all but the Ti formula, is forgiving to mix and has ample work time. I will use Devcon when it's specified (almost never) but day in and day out Marine Tex is what we use. Once mixed I stuff it in 5cc syringes to be able to place it air bubble free in the deepest recesses. 20 cc's is about all an action takes with some left over. I use tongue depressors to butter the action so I never see an air pocket. Then clean up is so easy I don't even tape up the stocks anymore. We use Q-Tips to clean up and a mill to detail. Comes out perfect every time.

 

[downlow]

Eyeball it and go. I'm sure I've never used the EXACT ratio twice, but every job has turned out perfect.

 

[sgtsmmiii]

I use my digital powder scale and just weigh it out, 9:1.

I set the scale to grams.
Using the bottom 1/4 inch of a plastic cup for a tray,
Zero out the scale with the cup on the scale.
I weigh a fair amount of putty in the cup.
Write down that weight and then divide by 9.
This is the weight of the hardner required.
Zero out the scale again with the putty and cup on there.
Now add hardner to the mix until the scale reads the amount you figured above.
Done!
Just mix it up and you're good to go.

Good Luck!
Mike

With some slight variations, this is how my OCD makes me do it, too.

 

[seanhagerty]

With some slight variations, this is how my OCD makes me do it, too.

I do it this way also. But instead of a cup I use freezer paper. I just work it with a putty knife to mix it together, then apply with a tongue depressor. I leave the excess out on the paper, and check it to see when it sets up. Once I see its set up nice and stiff, I pop the action out to make sure I didnt weld them together.

The first few times I had a lot of voids. I found out that if I apply devcon to both surfaces, I dont get them any more.

 

[Red_SC]

With some slight variations, this is how my OCD makes me do it, too.

Me too. Perhaps overkill, but I know it's right.

 

[Clark]

Epoxy is good for ~ 20kpsi in compression. If you look at the area of epoxy, the torque on the action screws, the pitch of the threads, and subtract off 50% screw friction, ... you will see that epoxy is way stronger than it needs to be for rifle bedding.

If you mix epoxy at different rations and measure the strength, it does make a difference, but it is forgiving.

What does it all mean?
The mix ratio is not the critical problem that mix temperature and epoxy freshness are.

Sangamo capacitors went out of business because their epoxy end caps had an out of control process of adding thickener. Air force techs were getting shocked when fighter power supplies had caps blow up.

What does THAT mean? Don't be adding a bunch of color or thickener without testing your process and ratios.