Gunsmithing DBM Bedding: Air Bubbles

Wheres-Waldo

Gunny Sergeant
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Minuteman
Nov 2, 2008
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Is it realistic for me to expect no air bubbles when bedding my DBM, specificly on the sides of the magazine well.

I bedded it and had a bunch of small air bubbles on the sides.
Ide imagine it would be easier with a thinner bedding compound, but Devcon is so damn thick.
 
Re: DBM Bedding: Air Bubbles

Wheres-Waldo said:
Is it realistic for me to expect no air bubbles when bedding my DBM, specificly on the sides of the magazine well.

I bedded it and had a bunch of small air bubbles on the sides.
Ide imagine it would be easier with a thinner bedding compound, but Devcon is so damn thick. [/quote

Is the bottom metal basically square, or do the sides have a draft to them?
 
Re: DBM Bedding: Air Bubbles

Its a strait wall, no draft to it at all.

I coated both the stock and my part in Devcon, its just most of it squeezes out when I push it in. Its a nice snug fit, just doesnt look that good once its removed.
 
Re: DBM Bedding: Air Bubbles

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wheres-Waldo</div><div class="ubbcode-body">Its a strait wall, no draft to it at all.

I coated both the stock and my part in Devcon, its just most of it squeezes out when I push it in. Its a nice snug fit, just doesnt look that good once its removed. </div></div>

When you bed something with straight walls, that is going to be your biggest challenge. Getting the bedding to stay put and keeping the air bubbles out. Model 70 actions are the worst. Typically, I will file a draft on straight walled bottom metal to alleviate the problem. If you choose to do that, take your time and don't use an aggresive file for the entire process. I will usually start with a "0" and work my way down and when it's close, go to paper. Start with 220, then 320 and finish with 400. Once the draft is in place, the compound will settle and compress nicely.
 
Re: DBM Bedding: Air Bubbles

The most important part in bedding the bottom metal is the area of the action screws. If the bottom metal is flat and the bedding is good in this location the rest is simply cosmetic.

This is the same with bedding an action. The most important part is the front receiver ring/lug area and the tang. Everything else is simply cosmetic to close up the gap between the stock and receiver.
 
Re: DBM Bedding: Air Bubbles

OK I think I should be fine. Thats actually the one place that looks better than any other. I cant help but think a thinner bedding material would make for alot better end result.
 
Re: DBM Bedding: Air Bubbles

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wheres-Waldo</div><div class="ubbcode-body">9:1 No? </div></div>

What he's referring to is not the ratio, but how you actually mix the two parts together. Mix in a way that does not introduce air into the compound.
 
Re: DBM Bedding: Air Bubbles

Oh, I didnt happen to think about that...
eek.gif
 
Re: DBM Bedding: Air Bubbles

It's not so much on how you mix the product together that creates the air bubbles or voids it's how it's spread out the bedding material into the stock before you drop in the action. Just simply dropping in the action can create voids or air pockets.

As for the bottom metal if the fit between the bottom metal and stock is snug or a real good close fit before bedding this can cause the bedding to skim away as you drop it into the stock leaving bedding in some places and not others. Sometimes the fit is so close it will skim all the bedded away and leave you with none along the sides.

What some will do is open up the stock a little more to allow more room for the bedding to stay instead of getting swiped off as you drop the bottom metal into the stock.