Sachs Dolmar Chainsaws Thread

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Hello to all,

I hope I'm not barging into anything here? When it comes to single cylinder radio control airplane engines-Sachs/Dolmar are by far the BEST!::msp_w00t: I have done many conversions, and I know you guys are going to frown on this but I cut all the unnecessary weight off of the crank casing, install a battery operated electronic ignition , make an engine mount, turn the carb with a phenolic manifold, some machining for a propeller hub and to the fly wheel also and d you got you self a lifetime engine. We don't even run close to what environments these saws are under for tree cutting. I've used many saws and sachs has the less vibration for the RPM we run per propeller efficiency that is approx 6,800 to 7,100 on the ground, + 10%-- or 1,000 in the air is what you pick up.

Attached is my P-40 Warhawk with a 5.8 Sachs-the hauls the mail around 100+ mph.

I'm looking for any saws that can't be used for tree cutting anymore per 166, 153, 152 anything in the 100cc + range- I'm thinking broken case were the chain bar mounts, etc that someone would want to sell. Basically the crank shaft assy , cyl head, , piston, engine crank case is what I can use

Thanks, Vinny

Another fellow RC & Chainsaw nut:)
 
5.8 eh?
If so, you just missed a good one on the bag.

I mill with 152s/153s and have a few 6 cube Husqvarnas as well.

Bet a 48mm stroke 166 mill would make that bad boy VERY BAD!

Yes--143- I think? so when I compared to the old Sachs chart (that I can't find anymore)? You guys have any Sachs charts that reference model # & cc or cu in?

What a sweet run nin motor that 5.8 was!!! Geepers I hated to see the motor go

In the hobby, we always reference the (cu in) via 4.2 cu in = Sachs 123 si, 6.0 or 6.2 cu in= Sachs 166, and I think 3.6 cu in. is a Sachs 120 around 62 cc?

Man--- 143 would have been nice for my P-47 I'm building! I can get a twin cyl China nip 100cc for about $600.00, but the opposed motors don't sometimes fit well in narrow warbird engine cowling, and those Sachs motor can take a joke and keep on tickin. A beat up Sachs 166 is what I would sell my kids for---How do you guys think a Husky motor would do? I need a 95cc minimum--

To give you an ideal of how I butcher that poor ole sachs 4.2 chain saw motor via photo that ended up in a Jap Zero, and a link to some better photo's of the P-40 if interested .

Radio Control P-40 Flown

Thanks to all and if you can keep me in mind-Vinny
 
No. I'm Keith. The only time my chainsaws fly is when I screw up. I know there is a sky kings group that flys not far from my house though and they have some nice planes.

Ha good one, Yipes --or maybe I should say I wouild not want to be around any flying chain saws!!!

Yes I know many of those guys in that club, I fly down at Lums Pond -DE
 
No. I'm Keith. The only time my chainsaws fly is when I screw up. I know there is a sky kings group that flys not far from my house though and they have some nice planes.

Also, being so close I have a box full of parts that came off saws, coils, etc etc, right now I got 6 or 7 sthil cut off saws-you need parts let me know-Vinny
 
I think it's cool that you guys prefer the old Sachs engines.

Me thinks you fly boys get the idea of them long stroke engines.

I have a Fichtel-Sachs sled engine I'm going to put on an old Sunstar. She oughta throw the grass fairly well.
 
I think it's cool that you guys prefer the old Sachs engines.

Me thinks you fly boys get the idea of them long stroke engines.

I have a Fichtel-Sachs sled engine I'm going to put on an old Sunstar. She oughta throw the grass fairly well.

Thanks for the support,

A question for the sachs guru's?

Will a 153 head, piston etc, mount on a 143 cases etc and work?

Will a 166 head, piston etc, mount on a 153 cases etc and work?

Will a 166 head, piston etc , mount on a 143 cases etc and work?
 
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Never tried,

143=40mm stroke
153=42mm stroke
166=48mm stroke

All of the above don't share much of anything in common, each is of it's own "block".
 
Never tried,

143=40mm stroke
153=42mm stroke
166=48mm stroke

All of the above don't share much of anything in common, each is of it's own "block".

Thanks, it appears so, and that little difference 2-4 mm-- can make a big difference!

So that said the cranks are different and piston dia obviously.

I was currious because when I was reviewing some parts manuals it appears some saws used the same cases, I guess maybe like the 120 verses 120 super.
 
Many of the Sachs Dolmar saws do use the same case. for example the 123, 133, 143, same case different bore (47, 52, 55mm respectively)
The 120si 116si same stroke (36mm) 49mm or 46mm bore. I have put a 272 Husqvarna top (52mm) on a 116si and ended up with 77cc. The problem is the piston skirt is a bit short and she free ports a little. My next try will be a 7900 top, same cc, but it is built for the longer stroke. Just need to find a intake tract complete.


Good on you for putting them power plants to work, I ain't anal 'bout keeping them saws. As long as them dudes are countin' 'em off and powering any application all is good.
 
Hello to all,

I hope I'm not barging into anything here? When it comes to single cylinder radio control airplane engines-Sachs/Dolmar are by far the BEST!::msp_w00t: I have done many conversions, and I know you guys are going to frown on this but I cut all the unnecessary weight off of the crank casing, install a battery operated electronic ignition , make an engine mount, turn the carb with a phenolic manifold, some machining for a propeller hub and to the fly wheel also and d you got you self a lifetime engine. We don't even run close to what environments these saws are under for tree cutting. I've used many saws and sachs has the less vibration for the RPM we run per propeller efficiency that is approx 6,800 to 7,100 on the ground, + 10%-- or 1,000 in the air is what you pick up.

Attached is my P-40 Warhawk with a 5.8 Sachs-the hauls the mail around 100+ mph.

I'm looking for any saws that can't be used for tree cutting anymore per 166, 153, 152 anything in the 100cc + range- I'm thinking broken case were the chain bar mounts, etc that someone would want to sell. Basically the crank shaft assy , cyl head, , piston, engine crank case is what I can use

Thanks, Vinny

Please tell us about that ignition you use? It would be of great help to many. The old Stihl 056 mags and some Sachs saws were known to have weak, no longer available ignitions.
Could you please tell us your source for them ?
 
Back to saws,

Here's one I put together for my little Brother. It is a SD 116si, he gets a new Carlton 20 inch with the saw, but I thought the old one looked better for a photo opp.

The Paint is Allis Chalmers Orange and seems 'bout as close as you can find off the shelf.

attachment.php
 
118 model

I know you folks are really interested in the biguns, but Dolmar also had a model in the early days which was very popular with the home owners in our area : the model 118. Very well built little machine that had the quality of its bigger brethern, and outlived many other saw generations.


Here's the smallest and regular 118, but quite rare (no number on the cover, and JET name of the starter).




the 'bigger' 118Super : i have two of them with minor differences



 
I know you folks are really interested in the biguns, but Dolmar also had a model in the early days which was very popular with the home owners in our area : the model 118. Very well built little machine that had the quality of its bigger brethern, and outlived many other saw generations.


Here's the smallest and regular 118, but quite rare (no number on the cover, and JET name of the starter).




the 'bigger' 118Super : i have two of them with minor differences




Very nice,...we never see them over here.
 
Please tell us about that ignition you use? It would be of great help to many. The old Stihl 056 mags and some Sachs saws were known to have weak, no longer available ignitions.
Could you please tell us your source for them ?

Hello to all,
Sorry I didn’t reply sooner been busy around the house.
The ignitions I use are from C & H Ignition, Unfortunately the guy (Bill Carpenter) an automobile mechanic who designed & started this business many years ago has retired, what a great guy! Someone did buy his company out so you can still buy his ignitions; I have not really had any correspondence with him yet-per website can give you some in-site.

About us - CH Ignitions

http://ch-ignitions.com/index.php?id_product=28&controller=product

I will try to explain the best I can, basically what I do with the engines via ignition is chuck up the chainsaw flywheel on an old Sachs crank shaft stub in my lathe, your end product will be a disc approx 3.5” in diameter. Needless to say you must be very careful doing this!!!! You must use a live center via tool post side for stability. Gingerly you must reach in with your tool post and bit and remove the inside area right before the cooling fins, it takes time and patience, depending on the engine sometimes I remove the fins first for clearance, I try to avoid the fin remove because it raises hell, like a card in the spokes of a bicycle. I do not cut into any of the center ferrous metal crank shaft mounting area were the aluminum is casted. I keep plunging into the inside fin/ magnet area until you here the magnets and counter balance scraping the tool bit, then move in towards the center to clear magnets etc.
When all said and done on the back of this disc a small rare earth magnet is epoxy mounted into a bore, on the crank case a mounting bracket is made to hold a hall sensor. I set the ignition timing at 28 ‘ BTDC, C&H ignitions have auto retarded timing, when you flip the prop the ignition retard to 0’ auto and is linear to advance with RPM to 28’, a good primed engine will start with half a flip of the prop. The ignition box is powered by a 4 cell-4.8v DC, 1000 mah minimum AA rechargeable battery. The ignition box is approx 2.5” x 2.5”x 1.25” and now I think smaller. The Ignition has 3 leads via spark plug boot & lead around 12” long , battery lead and 3 conductor Hall sensor connector of your choice. I’ve never tried it but you can probably get around 2 hours straight running time out of a battery.
I have thought of doing the same thing to one of my saws, the only problem I see is a saw needs a full flywheel with the OEM magnets via balance, pull start dogs etc, these magnets would have to be isolated not to interrupt the hall senor, or figure out timing using the OEM magnets new Hall sensor, also having clearance to mount the sensor, it can be done just takes time to figure out. Remember I do this with the crank case cut down to nothing, you can see the photo from my post page 157 #2344 I have plenty of room to work. Someone would have to figure out where to mount the battery, ignition box, switch etc. I would make the battery easily removed for quick replacement.

It can work, like any motor- that motor don't care were the spark is coming from, only cares about at the right time.

Hope this helps, anyone feel free to discuss, PM me and I will shoot you my phone #, I'm not to good at writing these forums,

Vinny,
 
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