Bill Hime

Hello Everyone!
So I'm buying a mill. I've read here that most mini mills do not have a high enough spindle speed for what we do. What is high enough and what mills have it other than Proxxon's mill?
 
Please help me spend my money
 
 
BIll

Most of the comments here, I believe, refer to spindle speed.  For a given spindle speed, cutting speed varies with the diameter of the tool, or on a lathe the diameter of the piece.  Cutting speed increases with diameter for a given spindle speed.  So, cutting speed, ideally, should be optimized for each individual setup based on the speed of the cutter at the cut.  Small diameter wood turnings, for example, require very high spindle speeds.
 
High spindle speeds on turnings not only produces a finer surface but also reduces torque on the piece at the cut, reducing breakage.
 
I believe the standard Sherline mill is a bit slow for routing wood, thus leaving a rough surface.  Although I do not have the high speed attachment, I believe it would be a good investment.  Would routers and Dremel type tools have very high spindle speeds for this reason - much higher than machining tools like lathes and mills that are basically designed for metal where recommended cutting speeds are much lower.
 
Ed
.

Thank you Mark! your input is always invaluable to me. Not to mention everyone else. Oh btw, links to more places to get lost in the details for one with significant OCD is not very helpful, lol!!!
 
Thank you Don and Frank!
 
Grant, appreciate all the help in spending my money, lol!
 
Update; We had to drop an extra $1,800.00 into the shop floor structure to support the equipment coming. So the mill/lathe combo will have to wait til the June billing cycle.
 
Ironically, with that sais, the Byrne's table saw arrived today along with the Grizzly 12" Extreme 5 hp, 220v cabinet saw. kinda the long and short of it! I'll post a pic of the two together..should be fun!
 
 
Bill

Thank you Mark! your input is always invaluable to me. Not to mention everyone else. Oh btw, links to more places to get lost in the details for one with significant OCD is not very helpful, lol!!!
 
Thank you Don and Frank!
 
Grant, appreciate all the help in spending my money, lol!
 
Update; We had to drop an extra $1,800.00 into the shop floor structure to support the equipment coming. So the mill/lathe combo will have to wait til the June billing cycle.
 
Ironically, with that sais, the Byrne's table saw arrived today along with the Grizzly 12" Extreme 5 hp, 220v cabinet saw. kinda the long and short of it! I'll post a pic of the two together..should be fun!
 
 
Bill

Thank you Mark! your input is always invaluable to me. Not to mention everyone else. Oh btw, links to more places to get lost in the details for one with significant OCD is not very helpful, lol!!!
 
Thank you Don and Frank!
 
Grant, appreciate all the help in spending my money, lol!
 
Update; We had to drop an extra $1,800.00 into the shop floor structure to support the equipment coming. So the mill/lathe combo will have to wait til the June billing cycle.
 
Ironically, with that sais, the Byrne's table saw arrived today along with the Grizzly 12" Extreme 5 hp, 220v cabinet saw. kinda the long and short of it! I'll post a pic of the two together..should be fun!
 
 
Bill

Thank you Mark! your input is always invaluable to me. Not to mention everyone else. Oh btw, links to more places to get lost in the details for one with significant OCD is not very helpful, lol!!!
 
Thank you Don and Frank!
 
Grant, appreciate all the help in spending my money, lol!
 
Update; We had to drop an extra $1,800.00 into the shop floor structure to support the equipment coming. So the mill/lathe combo will have to wait til the June billing cycle.
 
Ironically, with that sais, the Byrne's table saw arrived today along with the Grizzly 12" Extreme 5 hp, 220v cabinet saw. kinda the long and short of it! I'll post a pic of the two together..should be fun!
 
 
Bill

Bill,
 
You might also have a look here.. http://www.littlemachineshop.com/default.php  There's a lot of good information there.
 
Edit.. forgot to add this one also:  http://www.mini-lathe.com/mini_mill/Main/mini-mill.htm

Richard,
 
I'm not sure what the P/N on mine is... but here's a link to a review I did:  http://modelshipworld.com/index.php/topic/256-micromark-micromill-review/
 
It's not an upgrade as such but more of a backyard mechanic kludge.   I took off both pulleys and re-machined them on the lathe such that they fit on the opposite shafts from original.   I hope that makes sense.  If I get some time, I'll pop off the pulley cover and take a picture.

In respect to the back lash you mentioned. All mills that we are likely to encounter, have back lash. You need to determine what this is for the feed screws on your mill, and remember to take this into account when using it.\
 
Alternatly you could try to fit it with a digital readout, very expensive, but very accurate.

Hi Bill,
 
I have a big mill (42" table)  and I have used it for wood before.  I believe it has a maximum speed of 6k rpm.  I use it for metal most of the time, but when I have used it for wood, I have never had to get the rpms that high to do nice, clean cuts.  The real secret is the sharpness of the cutter, the number of flutes on the cutter and the speed at which you feed the wood into it.  You also have to pay attention to the direction that you feed the wood into the cutter, as to minimize tear-out.  I have an automatic feed on mine, but I almost never use it when cutting wood, only on metals. 
 
I have heard great things about Sherline mills though.  I have neither had one, nor have I used one, since my work is generally larger, and thus, a larger mill is required.  But if it were me, I would see about buying one that was a little larger, and more substantial in weight than the Sherline.  I know both Grizzly tools and Enco offer some inexpensive hobby mills, and they are cast iron beds.  This makes a big difference, as the heavier the mill, the more stability you have.  My mill weighs about 2 tons, so it is overkill for model building.
 
Matt

Mark, I think we both have the same, discontinued MM Micro mill (#84659).
I too am considering the Sherlines as replacement but would like to hear more about the 10,000 rpm upgrade to the MM. While it seems to working ok as is, I do not have a comparison to higher speeds so might be interested.
 
Richard.

Your gonna be delighted Bill. The Sherline machines are a real joy to use. And buying accessories for them is an endless hobby in itself - one that's bound to keep you broke. Don't ask me how I know..................

Thanks, Ian!  I am still not completely sure about whether I want to try scale plank lengths for the first layer.  In practice spiling runs, I have found it very difficult to get an accurate curvature at the point where the bow section meets the mid-ship section.  My spiled plank always seems to want to curve down and away from the edge of the bulwark at this point.  It might be that the tape is simply not sitting properly at this point, but it has happened just about every time I've practiced with it.  Cutting a longer plank would likely only exacerbate this problem, which is why I was leaning toward using shorter scale plank lengths.  I will likely try a full-length plank and see how it goes before making my decision.  
 
Anyway, the shaping of the last three stern filler blocks was a lot easier than I thought it would be!  I took a few pictures to document the process, even though everyone already knows how I do it.  Here's the shaped aft block:
 

 
And here is the next block, properly curved and fitted:
 

 

 

 
Here are the layers of balsa in the remaining space between the bulkheads:
 

 
And here are the results, displaying what I believe to be decent symmetry:
 

 

 

 

 
The process only took me about 3 hours, which brings me to a total of 61 hours spent on this project thus far.  I am hoping to find my electric plank bender in the mailbox today, so hopefully I can get started with my spiled planks tonight.  She's looking better and better, and I can't wait to see her with that first layer of planking on her hull! 

Very nice job, especially for a first time modeler.  Your blocking and hull fairing look to be right on.  The planking will go very smoothly.  Keep it up!

Thanks for the kind words, guys!  It has taken me a bit of time to post this update, as I've been a little busy lately.  I started the planking process over the weekend, so the work I'm about to show you took place on Saturday.  I did not get as many pictures of the actual spiling process as I would have liked, so perhaps I can document this procedure a little better next time.  For this first layer, I decided to use a single plank per row instead of going with scale plank lengths, as I felt that it might provide a smoother surface for the second layer (which will be done in scale lengths).  Anyway, I began by laying my painter's tape down along the curve of the bulkheads and over the lower edge of the bulwark.  Using the edge of my pencil, I marked the bulwark's edge.  I also marked the positions of each bulkhead edge.  Then, I placed the tape down on a series of three index cards:
 

 
Using my tick strips, I mark the width of the plank at the bulkhead positions.  Then, I use my ship's curve to draw the other edge of the spiled plank.  Next, I cut the shape of the spiled plank out of the index card material:
 

 
I lay the index card plank along the hull to check the fit, and if I'm satisfied with it, I trace around the pattern on my sheet of German lime and carefully cut it out with my X-Acto blade (this results in a slightly wider plank that I can trim to fit):
 

 
I make sure to leave some extra material at the bow and stern ends of the plank, which is trimmed off later.  Once the plank has been cut out from the sheet, I use my sanding stick to smooth the edges and take off a little material at a time, performing multiple test fittings, until it has the proper width at each bulkhead position.  This is the most time-consuming part of the spiling process.  When I'm satisfied with the fit and the shape of the plank, it's time to bend it.  
 
My method for bending the planks is very simple (I have yet to use the plank bender since the lime planks bend so easily).  I just run the plank under the faucet in my bathtub for about a minute or two, making sure the water is as hot as I can get it.  While the plank is under the flowing water, I gently press on it with my fingers, gradually forming an inward bend at the bow end and an outward twist in the stern end.  The spiled plank, which curves downward at the bow, naturally wants to assume the inwardly bent shape, and the wider stern end twists easily.  Thus far, I have found no need to soak the plank for a long period of time or apply any further heat.  After maybe 2 minutes (at most), I pat the plank dry with a towel and give it a test fitting on the ship.  
 
I adhere the plank to the bulkheads and filler blocks with CA glue, as it dries quickly enough for me to attach the plank while it is still quite flexible, and it is strong enough to hold the last-glued section of the plank in place while I incorporate small corrective bends in the plank to produce a better fit.  I start at the bow, making sure the edge of the plank is butted up against the stem and flush (it is at this point that I usually perform the final trimming of the stem end of the plank, to give it the right angle against the stem).  I glue this portion in place, allowing the glue to cure.  Then, I move on to the next section, making sure that the plank is sitting as flush and snug as possible.  I continue to glue each section and let it cure (which takes only seconds) all the way to the stern/transom.  I leave the overhanging portion of the stern end of the plank until the glue is completely dry, then trim it off so that the plank is flush with the transom (the transom is planked with only the second layer of planking, and this layer is meant to lay on top of the edges of the first-layer hull planks).  When that is done, I give the plank a light sanding to ensure that any edges are smooth and flush.  I also run a sanding stick or a need file along the bottom edge of the plank to remove any waviness.  
 
Here is my first starboard plank (there is a small gap between the plank and the bulwark between bulkheads 4 and 5, which looks bigger in the photo than it does in person, due to the presence of sawdust elsewhere along the plank edge;  this gap will disappear once I put down a layer of wood filler or drywall compound over the first layer of planking before sanding everything smooth when I'm done):
 

 

 

 
Here is the first port plank:
 

 

 

 
In this photo, you can see how the planks are fairly symmetrical at the stem:
 

 
Here's how they appear at the stern/transom:
 

 
And, finally, a shot of the underside:
 

After repeating the process for the second row of planking, here is the second port plank:
 

 

 

 

 

 
These next two photos shows how I leave the overhanging end of the plank at the stern/transom while the glue dries, then trim it so that it is flush with the transom:
 

 

 
Here is the second starboard plank:
 

 

 
Here's a shot of the symmetry at the bow:
 

 
And a shot of the stern:
 

 
And, finally, the underside:
 

With the third row of planking, the ship is starting to take shape (I mark the positions of the bulkheads on the completed planks in pencil so that I will know where they are when I determine the plank widths for the second layer):
 

 

 

 

 

 

 
Everything seems to be fitting together properly, and I think I'm maintaining the proper symmetry.
 

 

 

 
So, at the end of my session on Saturday, after approximately 67 hours of work on this project so far, I had completed 6 planks (out of a total of 26).  The planking process is going more smoothly than I had anticipated, and it's really rewarding to see the hull starting to take shape!  I'm a little nervous about transitioning into the vertical planking at the stern and laying the garboard strake, but I'm going to take my time and do my best, so hopefully it will look nice.  Based on my planking layout, I should not need any drop planks or stealers, which pleases me.  Even though no one is going to see this layer, it is excellent practice for the second layer, and I'm learning what techniques are better than others for giving the appearance of a nice tight fit. 
 
I'll probably do some more work on the model this weekend.  The process itself is fairly straightforward, but it is a little time-consuming.  I find that I'm usually a bit nervous when laying the plank because I want it to look perfect, but I'm usually pleased with the results.  I think it will look quite nice when it's filled and sanded.  Anyway, let me know what you think, guys!   

Looks like you are getting the right idea, and it's coming along nicely.
 
Two things to keep in mind based on your description of how you are doing this.
 
1) If you place the plank while it is still damp, it will have some shrinkage as it dries.  This will possibly cause small gaps to appear between planks.  To avoid this, make sure the plank is completely dry before you place it.
 
2) You don't mention beveling the edge of the planks.  Due to the curve of the hull, the edge of the plank that is going up against the already placed plank should have a bevel sanded into it to close the gap that will naturally open between the planks due to the angle between the planks.
 
I thought I had a drawing of the plank edge beveling, but I can't find it at the moment, so if what I said isn't clear, please let me know and I'll try to clarify it.

Bill,
 
Try it once you get it and test it.  If you get acceptable results, then that's great.  If you think a higher speed will help, than the speed upgrade is the ticket.  I have the MM Mini which now discontinued and after reworking the pulleys I can see the difference in milling wood at 2500 rpm and 10,000+ rpm.  When this thing dies, I would go with the Sherline and speed kit upgrade.

Hi Bill
 
I was able to pick up a used Sherline mill and lathe with a bunch of accessories a couple of years ago, and I'm extremely pleased with the setup.  I upgraded the mill with the 10,000 RPM package and would recommend it (although it's not absolutely necessary).  One accessory I highly recommend is the Sensitive Drilling Attachment.

Hey Bill, that sounds like the package I bought last summer and I love it. As mentioned above the accessories are what really make sherline shine, and trust me you will always want more

Richard,
Thank you. I was curious about the Micro Mark mill. I did take a look at the Sherline after Wacko Joe mentioned them. I know I read here somewhere it was suggested that 20,000 was needed to cut with precision at our scale. The Proxxon mill's the only one I could find that had that kind of speed.
 
Sherline has a mill and lathe combo package with a large number of accessories for both. It's priced around $2,500.00. Despite that, I'm taking the leap, working the cost into my capital budget for the shop
 
Bill

Richard,
Thank you. I was curious about the Micro Mark mill. I did take a look at the Sherline after Wacko Joe mentioned them. I know I read here somewhere it was suggested that 20,000 was needed to cut with precision at our scale. The Proxxon mill's the only one I could find that had that kind of speed.
 
Sherline has a mill and lathe combo package with a large number of accessories for both. It's priced around $2,500.00. Despite that, I'm taking the leap, working the cost into my capital budget for the shop
 
Bill

Richard,
Thank you. I was curious about the Micro Mark mill. I did take a look at the Sherline after Wacko Joe mentioned them. I know I read here somewhere it was suggested that 20,000 was needed to cut with precision at our scale. The Proxxon mill's the only one I could find that had that kind of speed.
 
Sherline has a mill and lathe combo package with a large number of accessories for both. It's priced around $2,500.00. Despite that, I'm taking the leap, working the cost into my capital budget for the shop
 
Bill

Richard,
Thank you. I was curious about the Micro Mark mill. I did take a look at the Sherline after Wacko Joe mentioned them. I know I read here somewhere it was suggested that 20,000 was needed to cut with precision at our scale. The Proxxon mill's the only one I could find that had that kind of speed.
 
Sherline has a mill and lathe combo package with a large number of accessories for both. It's priced around $2,500.00. Despite that, I'm taking the leap, working the cost into my capital budget for the shop
 
Bill