any interest in some custom dolmar/makita felling spikes?

[logicallycompromised]

hello good sirs or possible misses!
i made some felling spikes a couple weeks ago and found out they were a combination of too thin and too flexible, likely do to cheap steel alloyed with next to zero carbon. well i have put the stock ones back on for the time being and have drawn up a very similar design. the gullet in the lower section is deeper and the three upper teeth aim upwards where as the original design i made had horizontal top edges. i will be heading back to school around the end of the month and plan on making myself a pair of these. once the fitment has been verified i would be happy to cut several more out for others. i would sell them as a set with a roller chain catch. i would like to try and get around 28$ shipped for the kit but will consider and likely yield to the community.

i would like to hear others ideas on the roller catch. the idea i will toss out is...an aluminum bolt provided i can source them locally and then using some sort of plastic as a roller.

as the images will suggest and the caliper confirmed these will be a little more then 1/2" shorter then stock set. they are very similar length on the bottom so that the saw can use them as a point of contact just as the stock ones do.

i imagine within a month or so i will have them on my saw and could have them available to others soon there after that.
i will not hold anyone to it until i have a functional set on my saw but i will use this thread to try and gauge any interest.

the ultimate goal would be to sell enough to take a dent out of the cost of a top handle saw; either tanaka or echo 355t should suit me fine.

i am open to feedback and can alter them to suit the masses if a handful of people agree they prefer another style; e.g. longer spikes in either 4 or 5 tooth versions.

thank you for your time and live long and prosper!

the version i will be moving forward with as of the time of this post.

this image shows the slight offset in the upper mounting ears between the two spikes; the proposed design accounts for this.

they meet their demise when bucking a ~40" ash tree...i was letting the saw slide across to the back side during my top cut so that i could then let her bite in good and feed her all the wood on the far side before returning to the near side and those stumps sitting proud at ~ .040" were just a little to aggressive for the 20f degree ash...lol the lower tooth got all jacked up and here we are.

 

[wde_1978]

I started making my own spikes, but halted the project due to lack of time - and I realized my saws do fine with the stock spikes they've got.
I am still hoping to get back to that project at some point though.
Funny thing is I basically have access to 5 CNC mills at work, problem is they are production equipment and barely ever stand still.

Nice saw You have there, but I would have concerns running her without the cylinder cover.
Without the cylinder cover/shroud the flywheel no longer forces air through the cylinder fins and passive cooling cold cause hot spots - it might be OK if she's just a play-saw.

I like the look of the Baileys 5 point design, but the 4 point is also nice - 5 point would be nice for my PS-7900, and 4 point for my PS-6400.
The "B" version seems rather user specific.



Your design looks nice too.

You need either a harder alloy or thicker material.
I started with 2mm thick steel plates (alloy unknown, just something I found), but intended to eventually make spikes out of 2mm stainless steel (hoped to do so on a mill at work, but likely will never happen).

 

[CR888]

Just go on EBay and get the farmer tech roller catchers I just bought 10 for like $20 delivered. They catcher is plastic not ceramic but the work and appear decent in quality.

 

[logicallycompromised]

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hello good sir or possible miss!
our school has many nice machines that the students rarely use. if i did not have access to them this project would never make it out of my head.

i have added the oem shroud back on, based on you mentioning my oversight. there is a nice deflector right by the compression release that will direct air through the cooling fins. i may make this deflector just a little longer to encourage more air through the fins. but yes i feel much better having it on especially once the warmer weather gets here. thank you again!

as for the metal...leaning towards high carbon steel, in my mind i want something that can be heat treated to help get the stiffness we are after in a thinner package. cutting and shaping does not matter as much as they will be laser cut. thickness will be similar to stock which is 2mm as it appears you are already aware.

thank you for your time and suggestions.

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thank you for the suggestion. if i only make a couple sets i will likely just make them myself otherwise the route you went makes the most sense to me right now, thank you!

 

[logicallycompromised]

well took me a little longer then i wanted but i was able to get some cut some spikes to test the mounting holes and geometry earlier today; they fit like a glove and file will need no tweaking. the upper inside spike is not attached as the hole i cut is 4.2mm which is the recommended size for taping a m5 thread. the goal here being to use the threads i tap in the spike to secure the m5 bolt, if this does not work, no problem i will weld a nut to the back side. about a week ago i went over the files again and am glad i did, i did not fix all of my geometries in the first drawing and they got all jacked up as i tinkered with 5 spike profile.

as i was walking out of school i stopped to talk with a friend and share my excitement about this project. one of his colleagues, over heard the conversation and started to ask me questions about the project. the goal of the first set of questions i think was to try and undermine my understanding of the purpose of the spikes. at some point in our 20 minute conversation i was able to convey some level of competence that he will allow me to look at his 7900 he was quoted > 400$ to fix. we also had a mutual friend, small world as i was located about 45 minutes from home. i am happy i gave this person a chance, as normally i do not like dealing with abrasive people.

i have plans in the next several months to increase the output of this saw via ~ 220psi compression(domed piston, cut jug) with mild porting and timing. i am only trying to follow the model that those with more knowledge and experience then i have put forth. i will document the process as i go along for others to learn from my mistakes or find some motivation in the journey.

live long and prosper all!