Harman Magnum Stoker Restoration...

Harman Magnum Stoker Restoration...

PostBy: eelhc On: Fri Jul 03, 2009 11:32 pm

I bought a Magnum Stoker from another Nepacrossroader this spring and I'm finally getting around to restoring it. I've been getting a lot of interruptions so it's slow going but I've been making some progress in the last week or so.

Here's the Magnum Stoker prior to purchase. It was in pretty decent shape but I wanted it looking mint before installing it.
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I took it completely apart... even took the feet off.
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Looking pretty scary after pressure washing
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Only real trouble thus far has been removing screws that hold the brackets for the decorative tiles. I got 1 off but had to cut the heads on others. These little guys are stubborn! Lots of PB blaster and a screw extractor but no luck so far.
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The gasket cement on the doors are a bit of a pain as well. Some parts came off clean but there's lots that are left on the ash door.

Work area is a mess. I really like doing this sort of work outdoors when it's sunny and dry but the weather this year has not been cooperating. I'm going to replace bulk of the hardware but the bolts and screws are of unknown grade. I'll replace with 8.1 if I can find them.
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Next step is to use some AC coil cleaner to get the remaining dirt/grime off the inside of the stove and parts of the stoker mechanism. Then I'll sand down the inside and paint with VHT. I'm wondering how anal I have to be when it comes to getting the INSIDE to bare metal... There are areas that I just can't get to with the grinder.

I'll continue to document as I make progress... Hope to be done with this by the end of July.
eelhc
 
Stove/Furnace Make: Harman Magnum Stoker

Re: Harman Magnum Stoker Restoration...

PostBy: Highlander On: Sat Jul 04, 2009 7:15 am

Looking good so far.

I burned a VC Resolute on coal for many years before I found a Harman Mag on the local Craigslist. My stove was from a damp basement so there was lots of sanding and scraping to get that baby back into shape. My glass was fogged too so I ordered a piece of neoceram from an online dealer.

I think you will be amazed how much heat the Harman will throw off this winter. I thought my little VC did OK until I had the Mag in its place, there is no comparison, much more heat from much less coal. Only real drawback is that the Mag needs power to run, and the distribution blower can be a bit noisey.

Good luck with your restoration, keep us posted with pictures, we love pictures.

Bill A.
Highlander
 
Stoker Coal Boiler: Harman VF3000 Sold
Hand Fed Coal Stove: Vermont Castings Resolute
Coal Size/Type: Nut
Stove/Furnace Make: Harman
Stove/Furnace Model: VF3000 Stoker Boiler

Re: Harman Magnum Stoker Restoration...

PostBy: coalkirk On: Sat Jul 04, 2009 8:33 am

Looks good and those are great stoves. I restored two last year for resale and it was hard to part with them after they were all back to new condition. I almost kept one but just couldn't justify it to the CEO (wife). I guess three coal burners will have to do. :lol:
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

Visit Lehigh Anthracite

Re: Harman Magnum Stoker Restoration...

PostBy: shapps1313 On: Sat Jul 04, 2009 9:35 am

I bought one of the Magnums that Coalkirk restored,thanks Terry. I decided to make a new panel for the ash door. I was lucky to have a piece of .060 stainless steel and decided to "engine turn" it. It was a bugger to get the screws out of the mounting brackets, tried heat and PB blaster, no luck. I finally just broke the heads off and drilled and re-tapped them. If you do, don't drill too deep, you'll go right out the front. I am going to use stainless hardware for the the reattachment and lots of hi-temp antisieze just in case.
I'll post some pics of the panel when I get the chance.

Bill
shapps1313
 
Stove/Furnace Make: Harman
Stove/Furnace Model: Magnum Stoker

Re: Harman Magnum Stoker Restoration...

PostBy: ceccil On: Sat Jul 04, 2009 9:51 am

shapps1313 wrote:I finally just broke the heads off and drilled and re-tapped them. If you do, don't drill too deep, you'll go right out the front.


Is this from experience? :roll: Someday I would like to try to restore one myself. I would like to find one that uses no electric to use as a backup in case the power goes out. I guess I should learn how to use one of these manly-man stoves 1st. :D Have a happy and safe 4th everyone.

Jeff
ceccil
 
Stove/Furnace Make: Keystoker, Harman
Stove/Furnace Model: 90K, Mark III

Re: Harman Magnum Stoker Restoration...

PostBy: shapps1313 On: Sun Jul 05, 2009 7:56 am

No I didn't drill thru the front, but I know it does happen. The casting is not the thickest in that region. Also if you are not quite centered on the old bolt it could skate off and you'd be drilling into a "softer" metal that the bolt is made of and viola more pressure into softer metal means faster cutting means a deeper hole means an ugly bolt sticking thru the front.

Although, you can move over about a half inch and drill and tap new holes. Also being careful with the depth of your hole. Just be sure to use a bottoming tap for your final step,you'll have the maximum amount threads that way.

Bill
shapps1313
 
Stove/Furnace Make: Harman
Stove/Furnace Model: Magnum Stoker

Re: Harman Magnum Stoker Restoration...

PostBy: RMA On: Sun Jul 05, 2009 9:06 am

I would choose a damp day with moderate temps, in the shade. I would keep the stove's rusted parts wet with PHOSPHORIC ACID rust remover/converter and then scrub, rinse, dry and paint. Some marine stores have the ACID product under the name RUST BUST ( I buy at Pt. Pleasant Fisherman's sply./apprx $25/gal.concentrate). A very similar product is used in body shops and is available from NAPA (triple etch)..other very good products are available as Metal Prep. from Aircraft Spruce Supply Co.
This acid prep is *great* for pre-paint preparation...
Follow label directions...

Bob
RMA
 

Re: Harman Magnum Stoker Restoration...

PostBy: eelhc On: Sun Jul 05, 2009 9:06 pm

shapps1313 wrote:No I didn't drill thru the front, but I know it does happen. The casting is not the thickest in that region. Also if you are not quite centered on the old bolt it could skate off and you'd be drilling into a "softer" metal that the bolt is made of and viola more pressure into softer metal means faster cutting means a deeper hole means an ugly bolt sticking thru the front.

Although, you can move over about a half inch and drill and tap new holes. Also being careful with the depth of your hole. Just be sure to use a bottoming tap for your final step,you'll have the maximum amount threads that way.

Bill


Seems like a lot of trouble... If I can't get the screws out... I'm thinking about clamping the brackets in place and welding them down in a couple of spots. Just have to tell the wife the tile selection is more or less permanent (or until the next time I refinish the stove).
eelhc
 
Stove/Furnace Make: Harman Magnum Stoker

Re: Harman Magnum Stoker Restoration...

PostBy: eelhc On: Sun Jul 05, 2009 9:40 pm

RMA wrote:I would choose a damp day with moderate temps, in the shade. I would keep the stove's rusted parts wet with PHOSPHORIC ACID rust remover/converter and then scrub, rinse, dry and paint. Some marine stores have the ACID product under the name RUST BUST ( I buy at Pt. Pleasant Fisherman's sply./apprx $25/gal.concentrate). A very similar product is used in body shops and is available from NAPA (triple etch)..other very good products are available as Metal Prep. from Aircraft Spruce Supply Co.

This acid prep is *great* for pre-paint preparation...

Bob


I was going to use naval jelly (which I think is phosphoric acid based) but would consider stuff I can get in bulk (1 gallon or bigger). I am looking for stuff that isn't quite as nasty to work with... I just really hate working with chemicals. Beer's the only good way to destroy the liver.

last 2 steps before paint... naval jelly and clean off with denatured alcohol...
eelhc
 
Stove/Furnace Make: Harman Magnum Stoker

Re: Harman Magnum Stoker Restoration...

PostBy: shapps1313 On: Tue Jul 07, 2009 10:16 pm

If your going to weld, be careful welding steel to cast iron. I know it can be done,BUT, make sure you take it to someone who has welded dissimilar metals before. Cast iron does not like to be welded cold,Think long bake in an oven at around 400 degrees,Or even higher temp, not 100% certain on this. Also you'll need high nickel content rods. MIG does not always work on cast iron,this is from a bad experience MIG welding cast iron.


Bill
shapps1313
 
Stove/Furnace Make: Harman
Stove/Furnace Model: Magnum Stoker

Re: Harman Magnum Stoker Restoration...

PostBy: Matthaus On: Wed Jul 08, 2009 8:06 am

shapps1313 wrote:If your going to weld, be careful welding steel to cast iron. I know it can be done,BUT, make sure you take it to someone who has welded dissimilar metals before. Cast iron does not like to be welded cold,Think long bake in an oven at around 400 degrees,Or even higher temp, not 100% certain on this. Also you'll need high nickel content rods. MIG does not always work on cast iron,this is from a bad experience MIG welding cast iron.Bill


Best and easiest way is to braze the offending bracket to the cast iron door. Although welding is probably the last resort, I find that using a little heat to remove the bolts/screws prevents the broken fastener issue in the first place..... you know the old saying an ounce of prevention... :lol:

You are doing a nice job of the rebuild, getting a good coat of 1200* ceramic silver on the inside after rust removal seems to work the best for keeping things easy to keep clean.
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Matthaus
 
Stoker Coal Boiler: Leisure Line WL110 Dual Fuel, natural gas
Hot Air Coal Stoker Stove: Leisure Line Lil' Heater (rental house)
Coal Size/Type: Rice and Buckwheat Anthracite

Re: Harman Magnum Stoker Restoration...

PostBy: ceccil On: Wed Jul 08, 2009 11:08 am

The more I see the refurbs that you guys do, the more I wish I knew about this site before buying my stove brand new. I would have bought one of these rebuilds in a minuet before buying new again. :idea: Only thing I can't figure out is why you guys don't get together and start a new stove manufacturing company. With the knowledge you guys have, I would think it would be a very successfull company. :D

Jeff
ceccil
 
Stove/Furnace Make: Keystoker, Harman
Stove/Furnace Model: 90K, Mark III

Re: Harman Magnum Stoker Restoration...

PostBy: eelhc On: Wed Jul 08, 2009 1:47 pm

ceccil wrote:The more I see the refurbs that you guys do, the more I wish I knew about this site before buying my stove brand new. I would have bought one of these rebuilds in a minuet before buying new again. :idea: Only thing I can't figure out is why you guys don't get together and start a new stove manufacturing company. With the knowledge you guys have, I would think it would be a very successfull company. :D

Jeff


A year ago I hadn't burnt an ounce of coal in my life. Now I'm converted.

I am an electrical engineer by education/training/profession. I see a lot of areas where these stoves/furnaces/boilers could benefit from modern engineering/materials (the coal-trol comes to mind). Truth be told though... I don't think there's much $$$ to be made in the Anthracite coal industry... and the present designs that have been refined bit by bit over the years are simple and work well enough.
eelhc
 
Stove/Furnace Make: Harman Magnum Stoker

Electrolytic Derusting

PostBy: eelhc On: Wed Jul 08, 2009 9:36 pm

Quick update today...

Family and work obligations have kept me busy the last few days but I'm back at it. I could probably buzz through this with the wire wheel in a few nights but what fun is that? Here's a quick electrolytic derusting setup I set up tonight. Part is the tile back plate from the ash door.
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Yes... that's a kitty litter bucket...

Hooked up and at work...
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Oooo... bubbles...


Back tomorrow with the results!!!
eelhc
 
Stove/Furnace Make: Harman Magnum Stoker

Re: Harman Magnum Stoker Restoration...

PostBy: Matthaus On: Wed Jul 08, 2009 10:56 pm

Another idea:

Citric acid works great! No current needed, just make up a batch and dip the parts. I keep a jar of it for the door handles and hardware, been using the same solution for a year now and makes everything look nice and new.
Matthaus
 
Stoker Coal Boiler: Leisure Line WL110 Dual Fuel, natural gas
Hot Air Coal Stoker Stove: Leisure Line Lil' Heater (rental house)
Coal Size/Type: Rice and Buckwheat Anthracite

Visit Lehigh Anthracite