Thread: How to table mount Makita 3620 router?

Ok, here are some pics of the router...

Michael,
The screws are probably 4mm – same diameter as the 3 hp 3612 model. I have found that Hitachi use 5mm in both the TR12 and the M12. It may be that the manufacturers only intended the screws to hold the bottom plate in position.

There are probably two issues, the strength of the screw and the amount of purchase the head will have when suspending the router from the table top. A 4mm head may eventually pull through the table top, particularly if using counter sunk screws in MDF. If you opt to suspend the router using those screws, you may need to maintain a regular inspection program to ensure they are up to it. I am sure a lot of people suspend this machine and its heavier brother from four standard screws! Keep the holes close to the screw diamater and the screws tight.

Is there enough metal around the screw holes to drill them out and tap them to a larger diameter? If so will the larger screw head still work with the thickness of the plastic base material when not in the table?

Another alternative may be to counter-bore your table top to accept 4mm pan-head screws with a washer to overcome the possibility of pulling through.

In all probability your 4mm c/s screws may work fine provided they are maintained tight thereby preventing any slop when feeding timber past the cutter.

If they are 4mm it is getting pretty skinny, I reckon I'd use them to locate it in the same spot in the insert each time, but use something like the clamps on the triton router table base plate to hold the router in.

(BTW, my Hitachi, as Red neck said, uses 5mm and I have had no dramas with the high tensile allen headed c/s screws that hang it in my router table - I bought these specifically so the heads wouldn't chew out from screwing & unscrewing from the table each time I wanted to use it handheld)

M4 bolts will do ok, I have 2 3612s mounted that way (they are much heavier than the 3620) without problems! The 3620 is way too underpowered for table use, I suggest you look into a variable speed router with at least 1500watt (the 3620 is 1050). Also its plunge is very short which makes it a bad idea for a table router.

regards

Marios

Yep RM is right, my 3612c has been hanging by these original little bolts for about 5yrs. My table top is 3mm plate steel tho.

I'll be mounting it to a 10mm thick aluminium plate.

Red neck, you are correct in that the 4 screws hold the bottom plate to the base. I didn't check when I took the pics last night, but I don't think that the screw holes go right through the base. So, that looks like another issue.

routermaniac, the router is underpowered for table use, but this is fine since I'll only be routing 3mm pieces of MDF for templates. I have a larger router, which I'll probably mount at a later stage for heavier work.

Red neck and Scooter, out of interest, which Hitachi models do you have?

Harry72, thanks for the info, it's good to know the setup lasts a few years.

Yes I feel the same as Red Neck and Scooter, I felt that the screws on my Makita 3600BR were too smal (M4) so I drilled out the Holes and taped them deeper and with M5 threads
The M5 C/sunk cap screws still fit through the original black base plate should I ever need to refit it.
Cheers
Wayne

Originally Posted by mkat

Red neck and Scooter, out of interest, which Hitachi models do you have?

M12V, very happy with it.

Great stuff, thanks all for your suggestions.

Originally Posted by mkat

Red neck and Scooter, out of interest, which Hitachi models do you have?

An old TR12 I bought back about 1990 when they were the ducks-guts of routers. It sat under a Triton router table for years. I don't think the Japanese manufacturers ever intended their machines to be subjected to table abuse hence the M4 and M5 screws on the Makita and Hitachi. They must also swallow a lot of dust and it says a lot that they keep going in that environment. I have a Makita 3612 that I only ever use right side up. The soft start and variable speed are an improvement on the old TR12 but I don't know if it will last as well.

In contrast the US fixed base machines come with serious mounting bolts and are excellent for bolting under a sheet of MDF. They also have extremely accurate height adjustment providing easy incremental settings of say 1/64th inch. A wing nut on the side or similar device makes it easy to slip the motor out of the base for bit changing. If you have two bases it improves the versatility of the machine allowing its use freehand when not under the table. However a plunge router is probably a better freehand option and lighter too.

Those little M4 sized bolts can hold way more weight than a router.
Makita supply a dust shield for the 36 series to mount them upside down, you shouldnt be mounting your router directly to mdf with bolts use an insert plate instead, it doesnt take much to make one!

Originally Posted by Harry72

Those little M4 sized bolts can hold way more weight than a router ... you shouldnt be mounting your router directly to mdf with bolts use an insert plate instead, it doesnt take much to make one!

The M4 bolts are probably pretty tough critters but I wonder about the amount of metal (usually die-cast) that they are hanging on to in the router base. Don’t hear of too many failures though.

Harry we could probably get into a debate on router-top engineering here without too much trouble. I think the use of inserts adds more problems than they are worth. Firstly there is the cost of the insert, lift or whatever and secondly difficulties of fitting it exactly flush. If the insert is just slightly above or below the table it will lead to set-up problems with bit height and catches in feeding stock past the bit.

On the other hand a flat sheet of MDF has a tolerance of ‘just a few thou’ over its cross-section and if properly treated should last quite a while. Then you can turn it over and use the other side. Another advantage of the material is that it can be drilled and tapped for secure fastening of attachments. Coat it with shellac or Danish oil and an occasional coat of wax and it will provide an easy surface to work on.

If your router is attached to MDF using countersunk holes and the screws maintained tight the machine should sit rock steady and not cause damage to the screw holes. In fact my main concern in over-tightening the screws is possible damage to the router base, not the MDF.

Another area of over-engineering is the thickness of the top. Thin sheet will work fine if it is well braced underneath to avoid bumps and hollows.

Thanks again for your suggestions, here's where I'm at...

I drilled the aluminium plate and test fitted the router to it with four M4 screws, it's a good fit. Since the router isn't as heavy as the larger models, the M4 screws should be fine as mentioned by a few of you above. The router base also has an additional two M5 screw holes, but I don't think these will be necessary.

Now, the only issue is that the router has a switch that turns off when not pressed unfortunately, which is not ideal for table mounting. What do you think the best and safest way to deal with this is when the router is table mounted without replacing the switch, having two hands free to guide the stock (goes without say, but I'm stating it anyway...) and the capability to switch it off easily?