Making plans to build a concrete bowl lathe - opinions welcome.
My original intention was to have a friend help me fabricate a bowl lathe using some scrap steel he/we have laying around. I posted here a request for a spindle to use for the project. I got a lot of helpful responses and one of them mentioned using concrete as a base material...As it turns out I have extensive experience with precast concrete. It is an awesome building material.
That got me thinking and I sketched up my thoughts on paper.. I calculated the weight at almost 1000# with the motor and steel bed.
http://i158.photobucket.com/albums/t...4_edited-1.jpg
I plan on using a three horse three phase motor with variable speed control.
I still have not finalised the design of the headstock configuration, I wont until I have the spindle, pulley and motor in hand.
I planed on fabricating steel ways out of 3" or 4" square steel stock that will adjust vertically by bolting to some uni-strut embedded vertically into the concrete. The motor will also hang from embedded uni-strut.
I think if it is planned well with the uni-strut strategically located I would have a multitude of options for mounting up various fabricated tool rests.
What to consider??? I think the building of the concrete formwork will be a fun project in itself.
Any input is welcome.
I'm glad I found this site, there seems to be some real helpful, friendly and talented people her.. I think I'll hang around for a while.
Thanks in advance,
Mark
I have a line on a Vicmarc 300 spindle
From a member here.
Like this:
http://www.vicmarc.com/img/lathes/016-vl100-spindle.jpg
How to embed bearing race holders into the head will be a challenge. As will the pulley and drive belt. If the belt is to be between the bearings it will make it more practical to use steel for the headstock. We will see...and I love pics;)
Thanks for all the replies
Some good thing to consider posted here... and I will.:)
The drawing is rough but I did consider being able to stand close to the work. I actually have reliefs in the base as a sort of toe space so I could get right up to it with my knees touching the body of the lathe. I will likely make it wider than the 20" shown also.
As for leveling it, I will just use grout under the 'feet'. It wont ever move once I get it in place.
As for the bearing holders in the headstock, I will look into using the round tubing. I'm sketching up some details of the headstock that will accommodate the pulleys between the bearings. Two pieces of 1' x 4" steel box tubing with holes drilled in and round stock welded in place to receive the bearing races. The critical part will be making sure they are absolutely parallel.
Thanks again, i will keep you all posted.
Some good points made Rick
But what did the PM 3520 cost ya? over three grand I bet. and you are limmited to turning a 20 blank. Up the machine to a PM4224 and yer looking at 5 grand for a 24" blank.
I want to turn big bowls from the trees here in the sierras. The trees get real big in these parts:)
I figgure I can build this machine for about a grand if I shop wisely. I also greatly enjoy the designing and building of the machine. A big plus!!
I've been doing some more research on building my bowl lathe. I found a guy on the net that built one for his dad and he took a hundred an forty pics to document his build.(sans the concrete) :cool:
The critical part is the headstock that supports the spindle. His is overkill and I like it a lot! 2" dia shaft 18" long. The bearings are almost 3 hunnerd each :eek:
The 1-3/4" bearings I plan on using will be a few $ less than the 2" ones he used.
His album:
http://www.ncwoodworker.net/pp/showg...058&ppuser=639
Here is the components of his headstock assembly I plan to mimick just a hair smaller and cast in concrete.. He sandwiched a bunch of layers of plywood between the bearings.
http://i158.photobucket.com/albums/t.../headstock.jpg
Looks like a fun project..If it works out as well as planned I could see myself producing em for commercial sale.
Look forward to pics of the progress....as it progresses:p
A plan you can start with...
Mark
I have been watching this thread develop and have posted earlier regarding the use of concrete. You are headed in the right direction, just allow me to steer you a little bit... I have a plan for a machine capable of 48" diameter that has most of the kinks worked out. My buddy is an engineer and he helped me with making sure the design would safely absorb the radial forces at play at this scale. We are still working on the tailstock, as it is currently the weak link. PM me and I will send you a scan of the working drawing. I hope this gets you a little further down the road with this build.
Regards,
Travis R. Nelson
nelsonandsons@windstream.net
Thanks Travis... I'll be contacting you...and thanks!
Dave,
Do you read or just look at the pics? ;) :eek: j/k Its not my pic sittin on the phone book. But I do get the irony lol lol..
Jim,
I have seen the coring attachments and they do look interesting but I'm still working on wood bowl 101.
I'm not real interested in a tailstock at this point but I will make provisions for adding one to the ways later. For now, a faceplate and a good chuck will fit the bill.
I look forward to your input Travis. I have faith my design will develop and become a reality and any help is appreciated. The components are not cheap though so it may take a while and there is quite a bit of engineering envolved but that is my strong point.
As promised, I will keep you all posted.:) I kinda like it here in the midst of the creek:D