Sheared hinge pins

[bharbwyr]

I am attempting to restore a Scandia model 308, which I believe is a knock-off of the Vermont Castings "Defiant". Apparently, it sat unused in a damp basement long enough for the doors to seize up. When the previous owner tried to open them, three of the four hinge pins sheared off. I have been trying to drive the busted pins out of the stove body casting with no luck. I've used wd-40, propane torch heat and a hammer and nail-set. I really don't want to break off the castings. Does anyone know if these pins are possibly threaded? I have assumed till now that they are smooth or perhaps fluted.
Any ideas out there?

 

[thewoodlands]

I am attempting to restore a Scandia model 308, which I believe is a knock-off of the Vermont Castings "Defiant". Apparently, it sat unused in a damp basement long enough for the doors to seize up. When the previous owner tried to open them, three of the four hinge pins sheared off. I have been trying to drive the busted pins out of the stove body casting with no luck. I've used wd-40, propane torch heat and a hammer and nail-set. I really don't want to break off the castings. Does anyone know if these pins are possibly threaded? I have assumed till now that they are smooth or perhaps fluted.
Any ideas out there?

This works better than WD40. I bought this at True Value and WD40 does not come close to working like PB Blaster.

http://blasterchemical.com/display.cfm?p=50003&pid=4

Zap

 

[Skier76]

Brake fluid. Put a little on a Q-Tip...then dab the pins. Don't go nuts with the stuff; it'll eat through paint. Let it sit, then try again. I've used brake fluid on some really stubborn fasteners and it's always delivered.

 

[DAKSY]

+ 1 for drilling...
Grind or file the top of the hinge pin flat.
Centerpunch it near the middle of what's left.
Start with a drill smaller than the diameter of the pin.
Gradually increase the size of the drill until the pin is out.
If it IS threaded, you should be able to retap the threaded hole, but I'd
say from experience on most wood stoves the pins are either straight
dowels or have a knurl on them...
Use your WD-40 as a coolant to keep the drill bit from overheating
& losing its hardness & cutting edge prematurely...

 

[begreen]

Spot on Pook and Daksy, good advice. Drilling should give predictable and repairable results and the broken ones have to be drilled anyway.Personally I wouldn't waste the time on the Scandia, but if you are a handy tinkerer and like that stuff, go for it.

PS: What are you going to use for replacement pins?

 

[bharbwyr]

Got all the pins out mainly by drilling. Got a little discouraged on the last one when I broke off drill bits in both directions. But lots of heat and my trusty punch finally got it. I found that stainless steel 8/32 machine screws for the replacement pins fit just fine with a tad of tapping out (managed to break my tap too).

Here's another question. On this stove there is a hairline crack about 6" long running vertically up the middle of the right side. It is in the 1/2" wide flat valley between thicker parts of the casting. Is there any nifty way of sealing cracks like these? I will be applying cement to various joints and could try just buttering up the valley with the stuff. Is that likely to just fall off as it will not really be keyed in?

 

[SteveKG]

Congrat's on getting the pins removed....

I am not seeing the cement idea helping.

I am not a welder of any talent but I fool around with gas. I am not familiar with this stove, but your use of the word "casting" indicates it is iron?? Being me and not knowing much, if it were mine I'd probably think about brazing. Sometimes I fool around and get something done just fine. But this is your stove, not mine.... The cement on the crack is not a solution, though.

By the way, I once refurbished a cheap, used, import cast "morning stove" that I disassembled and sand blasted and painted and etc. When I reassembled, I used cement at the seams and over the next couple years, the expansion/contraction of the various pieces in relation to one another caused the cement in several places to crack and eventually come out. Not one of my successful endeavors.

 

[bharbwyr]

Given the size of this crack, I'm not really too worried about much affecting either the safety (my main concern), or performance of the stove (as long as it doesn't get worse!). It is in fact cast iron, from Taiwan. I am anticipating follow ups with the furnace cement at the joints, and I might go ahead and try the cement over the crack. It'll probably fall off. Going to the trouble of brazing seems to point towards jettisoning the whole project and buying a "real" stove. But times are a little tough right now and this thing was $50. on Craig's list. By the way, I've had wood stoves for years. But my last one (Jotul #3) has failed me and was just too small for my needs.

 

[begreen]

take an 1/8" drill and drill a small hole at the top of the crack to try and stop it's spread. Then fill best as you can inside and out with furnace cement.

 

[Dune]

Brazing is not good for wood stoves or any thing else involving high temperatures. A very experienced welder could fix the crack with a nickel or cast iron welding rod, but it would cost more than a taiwan stove is worth.
Do drill the crack out though, exactly as BeGreen said.

 

[rustynut]

bharb...
have done a bit of welding
not specifically cast iron though
do know that the metal needs to be preheated to some specified temp and then welded
for best results.
cant find my book right now for specifics.
i'm thinking that we just migwelded the part
without being too particular on the temp of the metal.
dont recall having any further problems afterwards.
while i cant guarantee that the heat from the stove may or may not affect it
i'm thinking that if it were mine that is what i would do
you should be able to find a weld shop that would have a go at it pretty reasonably
just ask when you go in
cant say for sure but probably not more than 15 or 20 bucks
economy the way it is they may be eager for some fill in work
good luck
rn

 

[Dune]

bharb...
have done a bit of welding
not specifically cast iron though
do know that the metal needs to be preheated to some specified temp and then welded
for best results.
cant find my book right now for specifics.
i'm thinking that we just migwelded the part
without being too particular on the temp of the metal.
dont recall having any further problems afterwards.
while i cant guarantee that the heat from the stove may or may not affect it
i'm thinking that if it were mine that is what i would do
you should be able to find a weld shop that would have a go at it pretty reasonably
just ask when you go in
cant say for sure but probably not more than 15 or 20 bucks
economy the way it is they may be eager for some fill in work
good luck
rn

I don't think so, the rods alone cost more than that.

 

[crazy_dan]

I keep a few nickel rods around for just such instances, I have had pretty good luck getting a good fire IE in a pile on the ground or in a shallow pit with charcoal going heating the piece up with the charcoal fire, till it is HOT welding it with nickel rod and then putting it back in to the fire and walking away till the fire is out cold and I can remove it by hand, but I have a little more experience than most of the backyard welders I have met.

Mild steel rod or mig wire will not work on cast Iron

 

[Dune]

I keep a few nickel rods around for just such instances, I have had pretty good luck getting a good fire IE in a pile on the ground or in a shallow pit with charcoal going heating the piece up with the charcoal fire, till it is HOT welding it with nickel rod and then putting it back in to the fire and walking away till the fire is out cold and I can remove it by hand, but I have a little more experience than most of the backyard welders I have met.

Mild steel rod or mig wire will not work on cast Iron

Dan, that is about ninety percent of what is needed for cast iron to be welded safely.

A couple other pointers for the DIY person, do not weave, short straight stringer beads work best, 1/2" long. Peen the weld lightly after each pass.

Take your time, don't let the workpeice get too hot.

Don't stand around either, don't want to lose your pre heat.

Always drill a small hole at each end of the crack.

Some peices are just too burnt to be saved (such things as coal grates, and inner baffle plates)

If you didn't use a fire to preheat (torch or forge for example) bury the part in wood ashes, lime or dry sand after welding (fiberglass insulation will work, but it will burn and smell very bad). The goal is to slow the cooling rate.

Brazing (technicaly it is bronze welding) is not to be used for things which will aproach or possibly surpass the melting temp of bronze in use. Actualy about 800F is max.

If you have a way to check the temp, 900 degrees F is good for preheat. If not, "black heat" is o.k.

 

[crazy_dan]

I keep a few nickel rods around for just such instances, I have had pretty good luck getting a good fire IE in a pile on the ground or in a shallow pit with charcoal going heating the piece up with the charcoal fire, till it is HOT welding it with nickel rod and then putting it back in to the fire and walking away till the fire is out cold and I can remove it by hand, but I have a little more experience than most of the backyard welders I have met.

Mild steel rod or mig wire will not work on cast Iron

Dan, that is about ninety percent of what is needed for cast iron to be welded safely.

A couple other pointers for the DIY person, do not weave, short straight stringer beads work best, 1/2" long. Peen the weld lightly after each pass.

Take your time, don't let the workpeice get too hot.

Don't stand around either, don't want to lose your pre heat.

Always drill a small hole at each end of the crack.

Some peices are just too burnt to be saved (such things as coal grates, and inner baffle plates)

If you didn't use a fire to preheat (torch or forge for example) bury the part in wood ashes, lime or dry sand after welding (fiberglass insulation will work, but it will burn and smell very bad). The goal is to slow the cooling rate.

Brazing (technicaly it is bronze welding) is not to be used for things which will aproach or possibly surpass the melting temp of bronze in use. Actualy about 800F is max.

If you have a way to check the temp, 900 degrees F is good for preheat. If not, "black heat" is o.k.

The way I weld anything warp sensitive is weld about 1/2" -1" long bead then skip 1/2"-1" then another 1/2"-1" bead
see attachment
the green line is the crack the purple dots is where I would drill a couple holes to help stop the crack
the blue lines are the 1st pass of beads the red lines are the 2nd set of beads to finish welding the crack (of course these would be on the crack not next to it).