Those MLA kits make into beautiful little machines. I bought one though I already have 3 die filers. The MLA's are just so nice looking.
Yes,all the die filers I have seen to run WAY too fast. I have said before: Files are like any other cutter; if they are run too fast,their teeth will get dull quickly and wear out. I hate that to happen with expensive die filer files.
I put a 1/2 H.P. DC motor on my Butterfly,and the improvement is remarkable. The machine no longer snaps small parts down on my pinched fingers. I tend to do small work,and this was a real problem.
I run my Butterfly at about 60 to 100 strokes per minute,and it files just fine without wearing my files out. Why didn't the makers make their machines run slower? I think it would have made things too complicated for them. Their large pulleys are almost as large as they can be made,and their motor pulleys are as small as possible. Anything beyond that,and they'd have been into a more complicated jack shaft situation. Today,we have DC motors and controls commonly available.
Surplus Sales sells small motors and controllers at reasonable prices. I even bought a 1 1/4 H.P. variable speed DC motor for my Wilton Square Wheel belt grinder. They don't sell that large a motor w/ controller any more,but last time I looked,they had plenty of smaller units. 1/2 H.P. is plenty for a die filer. I haven't bogged mine down yet.
I find a bastard cut file is fine for general use on a die filer. Too fine a file might choke up,though fine cut machine files were made. Since the file is held in a controlled manner by the machine,it does not produce as coarse a surface as does freehand filing with the same cut file.
About files: To save money,I have used a Nicholson 6" half round bastard file for years as my go to file for the Butterfly. I had to grind the edges of the front of the file down a bit to get it into the chuck. Also cut the tang off and rounded it over.Where the file emerges above the table,its sides are parallel. Not the safest thing to have a tang bobbing up and down near your eyes,even with goggles!! But,now,Nicholson files are made in Mexico,and are SOFT AS BUTTER. I have gone around here and scrounged every NOS Nicholson file made in USA that I can find. Also,by now,I have accumulated enough machine files and other files to last me out. But,with the file situation so bad,it is well worth conserving your files by running your machine slower.
Bahco files are still good. So are Dick and Pferd made in Germany. Avoid Grobet. Their "USA" files are made in INDIA!!! Vallorbes are still Swiss made,but other than files called "ski files",I have found it hard to find other types.
You have to order Bahco files and wait for them,I understand.
