Rottler Boring Bar

[Smalltownbassin]

I just got my hands on an old Rottler boring bar to start cleaning up some cylinders and was wondering if anyone has experience with a portable Rottler machine. Luckily the company is still in business so i was able to order a blind hole cutter specific to mercury outboards from their website so thats a plus. Good to know they still support their old equipment. But the Rottler bar doesnt have the functionality that a VN or KW has which leads me to some questions.

[Smalltownbassin]

[rock]

Congratulations. Nice piece that will pay for itself over and over.

Rock

[Smalltownbassin]

You ever cut a blind hole with one? It doesn't look like its even possible to not scratch the cylinder wall when returning the cutting head to home. It uses the lead screw to travel both up and down with no way of disengaging the rotation on its way. This means when i return the cutter it will rotate as it travels up leaving a spiral "scratch" on the cylinder wall. Of course if its a clean cut the bit shouldn't actually score the wall on the way up but it will surely leave a mark. Any tips for this problem? Just hone it out?

[Smalltownbassin]

This is my mounting plate design to go with it. the plate will bolt to my work bench and hang over the side. I will draw the block up from underneath using the head bolt pattern and a T slot cut in the plate to hold the bar down.

[rock]

I cut blind holes often but use a different brand. My rotation stops before retraction but regardless there will always be a mark. Honing follows boring so it doesn't matter. Play with it on a junk block cuz experience is what it takes, especially on blind bores. Good luck.

Rock

[Chaz]

Maybe it's the angle of the picture .. I'm surprised that there is no hand crank for raising and lowering the bar. How do you lower it to center the bar in the bore ?

My Kwik-Way has a mark on the centering pin knob that if you face it forward and extract the bar either by hand or let it do it mechanically, it will not scratch the bore. How, I don't know. Last cut should be a onesy-twosy on slow , so even if it did foul , it should be so slight that it wouldn't matter. There is always a drop of oil to keep it from snowballing.

You should always leave .003 to hone. Any less and it could shadow the bore with tool marks .. why take a chance.

Neat ol machine, might look out of place on a nice new billet plate .. LOL

[Smalltownbassin]

I'm no photographer lol. No hand crank on this model at all. I will have to run the machine down without a cutter to the desired depth and extend the dogs to center it. Then ill lock the bar down, retract the dogs, run the head back up, set my tool and commence cutting. There is a rapid advance and return lever in the main controls you see on top but there is no way to disengage the rotation in either direction. Its pretty obvious that Rottler designed this for through hole cutting but they did design a blind cutter after the fact specifically for Merc blocks according to the tool description on the website. Its definitely a capable machine though. It will just take some practice and time to learn its temperament. Seems like KW and VN designed models that suited blind bores much better than Rottler on portable machines but i just couldn't afford one. I did what we all do...buy the best possible tools that my wallet will allow, learn them well, upgrade as i progress in skill and experience. Just so happens that the tool i could afford is the one that may be the hardest to learn lol.

[Smalltownbassin]

Once i get the plate ill shoot a video of the operation of the machine that you guys can look at to see if you have any tips or pointers to give. I am definately going to have to come up with a way to accurately set the offset tool in the mic since the mic is designed for straight tools. maybe as simple as a caliper measurement of the tool protruding from the tool holder since that is what the mic does in this instance.

[David - WI]

If the company is still in business... why don't you order a manual for the machine you have?

[Smalltownbassin]

If the company is still in business... why don't you order a manual for the machine you have?

I have one. Nothing on blind boring in it.

[skeeter91]

I did something similar with a VN bar. I use a small hand hoist to lift the bar off the table which rotates on center. Made torque plates that bolt to the cylinder head bolt-holes and to the table from 1' aluminum stock. I use an indicator to locate the bar dead-on center of the bore, use the paws to get it close. The frame was easy enough to fab up and i can roll it anywhere in my shop to store it when not in use.

[Chaz]

It might be as simple as making a ring that goes over the mike, held in place by a set screw .. to increase the diameter (contact face) enough to work with your drop leg cutter.

With no way to raise and lower the bar by hand .. you might need to find another way to spot face the top of the sleeve once it's installed.

You have a great attitude towards learning the machine and making it work for you

Good prices on stuff we need to keep our machines working for us ..

https://beamequipment.store/

[Smalltownbassin]

It might be as simple as making a ring that goes over the mike, held in place by a set screw .. to increase the diameter (contact face) enough to work with your drop leg cutter.

With no way to raise and lower the bar by hand .. you might need to find another way to spot face the top of the sleeve once it's installed.

You have a great attitude towards learning the machine and making it work for you

Good prices on stuff we need to keep our machines working for us ..

https://beamequipment.store/

Best idea yet! The simplest and most accurate for repeatable results solution. Thank you!

[Chaz]

Home made ~ hand made tools are the best ..

Waitin on $10 dollars worth of parts for a Ryobi sawzall I found in the neighbor's trash pile .. so i can finish my new paint can shaker ... both rattle can and quart friendly ..